Re: Question about bus bar safety
I had a FITALY keyboard on my ok’d Windows smart phones. It was never pitted to IOS.?
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On Mar 29, 2021, at 3:00 PM, Daniel Michaels via groups.io <nov32394@...> wrote:
?
A general warning at the electrical panel stating that "This boat has 12 and 48 volt buss bars.
Dan
On Monday, March 29, 2021, 12:27:51 PM MDT, Mike hurley via groups.io <redwood1957@...> wrote:
Seams as if there should be color codes for ac/ DC48 and dc12 for pos/ and neg On Sat, Mar 27, 2021 at 2:03 PM, Ryan Sweet <ryan@...> wrote: Typo, hopefully obvious
“48v or 12v”
Why do we still use asdf keyboard layouts on thumb driven mobile phones? Sigh.
> On Mar 27, 2021, at 10:57, Ryan Sweet via groups.io <ryan= [email protected]> wrote: >
> ?For those of you that have 12v systems and 48v systems, is there a standard or convention for making it really clear that a given bus bar is 48v or 12c?
>
> Mine are in very different places in the boat and I’ve taken to putting plastic covers over the top and then taping really big labels on them and updating the drawings kept on board (still I’m trying to think of someone working on the boat with no drawing and no history of the installation etc). I know they could and should check with the multimeter but I also feel an obligation to protect a future diy boat owner from themselves if they fail to do that. Hence, wondering if there is some convention.
>
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>
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Re: Question about bus bar safety
Colored heat shrink?tubing is also good but avoid electrical?tape it turns too goo on a boat.
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Perhaps an etched placards would be a good ?idea. They can be purchased laser cut at a trophy shop for just a few dollars.
Thanks, Tommy. This is THE way to do it ! By the pro's.
But not many ordinary boat owners would do so...;-(
On Tuesday, 30 March 2021, 04:10:51 GMT+8, Tommy rochester < troche289@...> wrote:
You could do color coding with electrical tape. In high voltage ac panels will have at the terminations red, orange or yellow wrapped on the wire to identify high voltage.? You could just make a legend identifying what colors you use for varying voltage (48, 24, 12, 120ac). Just be sure to mark both ends of the wire. Any time you open up anything you will automatically know what you are working with.?
Printed plastic labels have a tendency to peel off. Leaving you clueless. When they ARE in (the correct) place, it is good !
I bought a swedish boat, labelled extensively by the former DIY owner. But some were peeled off, some showing wrong. In swedish, of course, but no problem for me. I decided not to trust those labels.
In general, less that 70V is not considered "dangerous" in a EE's mind. So. just tell your coming new owner of your carefully designed DIY boat, that there are more than the usual 12V or 24V system onboard. That'll jusitfy the use of a multimeter - you're so right, Ryan !
(I'll design my upcoming 48V 12KW motor and battery system to be possible to deliver 96V to the motor. "Nitro" electric, for emergencies !)
I would make a printed documentation of the system (sealed ?), to follow the boat documents. Then your back is free. New owner has to read all docs before using the boat,right ?
Carsten
On Tuesday, 30 March 2021, 03:08:36 GMT+8, Ryan Sweet < ryan@...> wrote:
That’s a good one, I’ll make good use of the label maker this week. ;-) I’m going to add “always use a multimeter to verify your assumptions about the circuit before beginning work.” ?
A general warning at the electrical panel stating that "This boat has 12 and 48 volt buss bars.
Dan
On Monday, March 29, 2021, 12:27:51 PM MDT, Mike hurley via <redwood1957= [email protected]> wrote:
Seams as if there should be color codes for ac/ DC48 and dc12 for pos/ and neg On Sat, Mar 27, 2021 at 2:03 PM, Ryan Sweet Typo, hopefully obvious
“48v or 12v”
Why do we still use asdf keyboard layouts on thumb driven mobile phones? Sigh.
>
> ?For those of you that have 12v systems and 48v systems, is there a standard or convention for making it really clear that a given bus bar is 48v or 12c?
>
> Mine are in very different places in the boat and I’ve taken to putting plastic covers over the top and then taping really big labels on them and updating the drawings kept on board (still I’m trying to think of someone working on the boat with no drawing and no history of the installation etc). I know they could and should check with the multimeter but I also feel an obligation to protect a future diy boat owner from themselves if they fail to do that. Hence, wondering if there is some convention.
>
>
>
>
|
Re: Question about bus bar safety
Perhaps an etched placards would be a good ?idea. They can be purchased laser cut at a trophy shop for just a few dollars.
toggle quoted message
Show quoted text
Thanks, Tommy. This is THE way to do it ! By the pro's.
But not many ordinary boat owners would do so...;-(
On Tuesday, 30 March 2021, 04:10:51 GMT+8, Tommy rochester < troche289@...> wrote:
You could do color coding with electrical tape. In high voltage ac panels will have at the terminations red, orange or yellow wrapped on the wire to identify high voltage.? You could just make a legend identifying what colors you use for varying voltage (48, 24, 12, 120ac). Just be sure to mark both ends of the wire. Any time you open up anything you will automatically know what you are working with.?
Printed plastic labels have a tendency to peel off. Leaving you clueless. When they ARE in (the correct) place, it is good !
I bought a swedish boat, labelled extensively by the former DIY owner. But some were peeled off, some showing wrong. In swedish, of course, but no problem for me. I decided not to trust those labels.
In general, less that 70V is not considered "dangerous" in a EE's mind. So. just tell your coming new owner of your carefully designed DIY boat, that there are more than the usual 12V or 24V system onboard. That'll jusitfy the use of a multimeter - you're so right, Ryan !
(I'll design my upcoming 48V 12KW motor and battery system to be possible to deliver 96V to the motor. "Nitro" electric, for emergencies !)
I would make a printed documentation of the system (sealed ?), to follow the boat documents. Then your back is free. New owner has to read all docs before using the boat,right ?
Carsten
On Tuesday, 30 March 2021, 03:08:36 GMT+8, Ryan Sweet < ryan@...> wrote:
That’s a good one, I’ll make good use of the label maker this week. ;-) I’m going to add “always use a multimeter to verify your assumptions about the circuit before beginning work.” ?
A general warning at the electrical panel stating that "This boat has 12 and 48 volt buss bars.
Dan
On Monday, March 29, 2021, 12:27:51 PM MDT, Mike hurley via <redwood1957= [email protected]> wrote:
Seams as if there should be color codes for ac/ DC48 and dc12 for pos/ and neg On Sat, Mar 27, 2021 at 2:03 PM, Ryan Sweet Typo, hopefully obvious
“48v or 12v”
Why do we still use asdf keyboard layouts on thumb driven mobile phones? Sigh.
>
> ?For those of you that have 12v systems and 48v systems, is there a standard or convention for making it really clear that a given bus bar is 48v or 12c?
>
> Mine are in very different places in the boat and I’ve taken to putting plastic covers over the top and then taping really big labels on them and updating the drawings kept on board (still I’m trying to think of someone working on the boat with no drawing and no history of the installation etc). I know they could and should check with the multimeter but I also feel an obligation to protect a future diy boat owner from themselves if they fail to do that. Hence, wondering if there is some convention.
>
>
>
>
|
Re: Question about bus bar safety
Thanks, Tommy. This is THE way to do it ! By the pro's.
But not many ordinary boat owners would do so...;-(
On Tuesday, 30 March 2021, 04:10:51 GMT+8, Tommy rochester <troche289@...> wrote:
You could do color coding with electrical tape. In high voltage ac panels will have at the terminations red, orange or yellow wrapped on the wire to identify high voltage.? You could just make a legend identifying what colors you use for varying voltage (48, 24, 12, 120ac). Just be sure to mark both ends of the wire. Any time you open up anything you will automatically know what you are working with.?
toggle quoted message
Show quoted text
Printed plastic labels have a tendency to peel off. Leaving you clueless. When they ARE in (the correct) place, it is good !
I bought a swedish boat, labelled extensively by the former DIY owner. But some were peeled off, some showing wrong. In swedish, of course, but no problem for me. I decided not to trust those labels.
In general, less that 70V is not considered "dangerous" in a EE's mind. So. just tell your coming new owner of your carefully designed DIY boat, that there are more than the usual 12V or 24V system onboard. That'll jusitfy the use of a multimeter - you're so right, Ryan !
(I'll design my upcoming 48V 12KW motor and battery system to be possible to deliver 96V to the motor. "Nitro" electric, for emergencies !)
I would make a printed documentation of the system (sealed ?), to follow the boat documents. Then your back is free. New owner has to read all docs before using the boat,right ?
Carsten
On Tuesday, 30 March 2021, 03:08:36 GMT+8, Ryan Sweet < ryan@...> wrote:
That’s a good one, I’ll make good use of the label maker this week. ;-) I’m going to add “always use a multimeter to verify your assumptions about the circuit before beginning work.” ?
A general warning at the electrical panel stating that "This boat has 12 and 48 volt buss bars.
Dan
On Monday, March 29, 2021, 12:27:51 PM MDT, Mike hurley via <redwood1957= [email protected]> wrote:
Seams as if there should be color codes for ac/ DC48 and dc12 for pos/ and neg On Sat, Mar 27, 2021 at 2:03 PM, Ryan Sweet Typo, hopefully obvious
“48v or 12v”
Why do we still use asdf keyboard layouts on thumb driven mobile phones? Sigh.
>
> ?For those of you that have 12v systems and 48v systems, is there a standard or convention for making it really clear that a given bus bar is 48v or 12c?
>
> Mine are in very different places in the boat and I’ve taken to putting plastic covers over the top and then taping really big labels on them and updating the drawings kept on board (still I’m trying to think of someone working on the boat with no drawing and no history of the installation etc). I know they could and should check with the multimeter but I also feel an obligation to protect a future diy boat owner from themselves if they fail to do that. Hence, wondering if there is some convention.
>
>
>
>
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Re: Question about bus bar safety
You could do color coding with electrical tape. In high voltage ac panels will have at the terminations red, orange or yellow wrapped on the wire to identify high voltage.? You could just make a legend identifying what colors you use for varying voltage (48, 24, 12, 120ac). Just be sure to mark both ends of the wire. Any time you open up anything you will automatically know what you are working with.?
toggle quoted message
Show quoted text
Printed plastic labels have a tendency to peel off. Leaving you clueless. When they ARE in (the correct) place, it is good !
I bought a swedish boat, labelled extensively by the former DIY owner. But some were peeled off, some showing wrong. In swedish, of course, but no problem for me. I decided not to trust those labels.
In general, less that 70V is not considered "dangerous" in a EE's mind. So. just tell your coming new owner of your carefully designed DIY boat, that there are more than the usual 12V or 24V system onboard. That'll jusitfy the use of a multimeter - you're so right, Ryan !
(I'll design my upcoming 48V 12KW motor and battery system to be possible to deliver 96V to the motor. "Nitro" electric, for emergencies !)
I would make a printed documentation of the system (sealed ?), to follow the boat documents. Then your back is free. New owner has to read all docs before using the boat,right ?
Carsten
On Tuesday, 30 March 2021, 03:08:36 GMT+8, Ryan Sweet < ryan@...> wrote:
That’s a good one, I’ll make good use of the label maker this week. ;-) I’m going to add “always use a multimeter to verify your assumptions about the circuit before beginning work.” ?
A general warning at the electrical panel stating that "This boat has 12 and 48 volt buss bars.
Dan
On Monday, March 29, 2021, 12:27:51 PM MDT, Mike hurley via <redwood1957= [email protected]> wrote:
Seams as if there should be color codes for ac/ DC48 and dc12 for pos/ and neg On Sat, Mar 27, 2021 at 2:03 PM, Ryan Sweet Typo, hopefully obvious
“48v or 12v”
Why do we still use asdf keyboard layouts on thumb driven mobile phones? Sigh.
>
> ?For those of you that have 12v systems and 48v systems, is there a standard or convention for making it really clear that a given bus bar is 48v or 12c?
>
> Mine are in very different places in the boat and I’ve taken to putting plastic covers over the top and then taping really big labels on them and updating the drawings kept on board (still I’m trying to think of someone working on the boat with no drawing and no history of the installation etc). I know they could and should check with the multimeter but I also feel an obligation to protect a future diy boat owner from themselves if they fail to do that. Hence, wondering if there is some convention.
>
>
>
>
|
Re: Question about bus bar safety
Printed plastic labels have a tendency to peel off. Leaving you clueless. When they ARE in (the correct) place, it is good !
I bought a swedish boat, labelled extensively by the former DIY owner. But some were peeled off, some showing wrong. In swedish, of course, but no problem for me. I decided not to trust those labels.
In general, less that 70V is not considered "dangerous" in a EE's mind. So. just tell your coming new owner of your carefully designed DIY boat, that there are more than the usual 12V or 24V system onboard. That'll jusitfy the use of a multimeter - you're so right, Ryan !
(I'll design my upcoming 48V 12KW motor and battery system to be possible to deliver 96V to the motor. "Nitro" electric, for emergencies !)
I would make a printed documentation of the system (sealed ?), to follow the boat documents. Then your back is free. New owner has to read all docs before using the boat,right ?
Carsten
On Tuesday, 30 March 2021, 03:08:36 GMT+8, Ryan Sweet <ryan@...> wrote:
That’s a good one, I’ll make good use of the label maker this week. ;-) I’m going to add “always use a multimeter to verify your assumptions about the circuit before beginning work.”
toggle quoted message
Show quoted text
On Mar 29, 2021, at 12:00, Daniel Michaels via groups.io <nov32394@...> wrote:
?
A general warning at the electrical panel stating that "This boat has 12 and 48 volt buss bars.
Dan
On Monday, March 29, 2021, 12:27:51 PM MDT, Mike hurley via groups.io <redwood1957@...> wrote:
Seams as if there should be color codes for ac/ DC48 and dc12 for pos/ and neg On Sat, Mar 27, 2021 at 2:03 PM, Ryan Sweet <ryan@...> wrote: Typo, hopefully obvious
“48v or 12v”
Why do we still use asdf keyboard layouts on thumb driven mobile phones? Sigh.
> On Mar 27, 2021, at 10:57, Ryan Sweet via groups.io <ryan= [email protected]> wrote: >
> ?For those of you that have 12v systems and 48v systems, is there a standard or convention for making it really clear that a given bus bar is 48v or 12c?
>
> Mine are in very different places in the boat and I’ve taken to putting plastic covers over the top and then taping really big labels on them and updating the drawings kept on board (still I’m trying to think of someone working on the boat with no drawing and no history of the installation etc). I know they could and should check with the multimeter but I also feel an obligation to protect a future diy boat owner from themselves if they fail to do that. Hence, wondering if there is some convention.
>
>
>
>
|
Re: Question about bus bar safety
That’s a good one, I’ll make good use of the label maker this week. ;-) I’m going to add “always use a multimeter to verify your assumptions about the circuit before beginning work.”
toggle quoted message
Show quoted text
On Mar 29, 2021, at 12:00, Daniel Michaels via groups.io <nov32394@...> wrote:
?
A general warning at the electrical panel stating that "This boat has 12 and 48 volt buss bars.
Dan
On Monday, March 29, 2021, 12:27:51 PM MDT, Mike hurley via groups.io <redwood1957@...> wrote:
Seams as if there should be color codes for ac/ DC48 and dc12 for pos/ and neg On Sat, Mar 27, 2021 at 2:03 PM, Ryan Sweet <ryan@...> wrote: Typo, hopefully obvious
“48v or 12v”
Why do we still use asdf keyboard layouts on thumb driven mobile phones? Sigh.
> On Mar 27, 2021, at 10:57, Ryan Sweet via groups.io <ryan= [email protected]> wrote: >
> ?For those of you that have 12v systems and 48v systems, is there a standard or convention for making it really clear that a given bus bar is 48v or 12c?
>
> Mine are in very different places in the boat and I’ve taken to putting plastic covers over the top and then taping really big labels on them and updating the drawings kept on board (still I’m trying to think of someone working on the boat with no drawing and no history of the installation etc). I know they could and should check with the multimeter but I also feel an obligation to protect a future diy boat owner from themselves if they fail to do that. Hence, wondering if there is some convention.
>
>
>
>
|
Re: Question about bus bar safety
A general warning at the electrical panel stating that "This boat has 12 and 48 volt buss bars.
Dan
On Monday, March 29, 2021, 12:27:51 PM MDT, Mike hurley via groups.io <redwood1957@...> wrote:
Seams as if there should be color codes for ac/ DC48 and dc12 for pos/ and neg
toggle quoted message
Show quoted text
On Sat, Mar 27, 2021 at 2:03 PM, Ryan Sweet <ryan@...> wrote: Typo, hopefully obvious
“48v or 12v”
Why do we still use asdf keyboard layouts on thumb driven mobile phones? Sigh.
> On Mar 27, 2021, at 10:57, Ryan Sweet via groups.io <ryan= [email protected]> wrote: >
> ?For those of you that have 12v systems and 48v systems, is there a standard or convention for making it really clear that a given bus bar is 48v or 12c?
>
> Mine are in very different places in the boat and I’ve taken to putting plastic covers over the top and then taping really big labels on them and updating the drawings kept on board (still I’m trying to think of someone working on the boat with no drawing and no history of the installation etc). I know they could and should check with the multimeter but I also feel an obligation to protect a future diy boat owner from themselves if they fail to do that. Hence, wondering if there is some convention.
>
>
>
>
|
Re: Question about bus bar safety
Seams as if there should be color codes for ac/ DC48 and dc12 for pos/ and neg
toggle quoted message
Show quoted text
On Sat, Mar 27, 2021 at 2:03 PM, Ryan Sweet <ryan@...> wrote: Typo, hopefully obvious
“48v or 12v”
Why do we still use asdf keyboard layouts on thumb driven mobile phones? Sigh.
> On Mar 27, 2021, at 10:57, Ryan Sweet via groups.io <ryan= [email protected]> wrote: >
> ?For those of you that have 12v systems and 48v systems, is there a standard or convention for making it really clear that a given bus bar is 48v or 12c?
>
> Mine are in very different places in the boat and I’ve taken to putting plastic covers over the top and then taping really big labels on them and updating the drawings kept on board (still I’m trying to think of someone working on the boat with no drawing and no history of the installation etc). I know they could and should check with the multimeter but I also feel an obligation to protect a future diy boat owner from themselves if they fail to do that. Hence, wondering if there is some convention.
>
>
>
>
|
Re: Ang.:Re: [electricboats] Material Choices and Thrust Bearings
Great info in that thread from Boatdesign.net but no conclusions for smaller vessels (<12T).?? Most of the links in the thread are old and go to 404.? But still useful stuff.
This stood out in the Mike Johns reply #6: ----- It would be nice to find a commercial bearing housing for two tapered roller bearings and seals. But there are only the high end marketed products mentioned before and they are probably not much better than the spherical roller bearing. -----
Isn't the trailer hub a housing for two tapered roller bearings and seals??
With regard to the double spherical roller bearing, if there is a suitable sized sealed version and a suitable housing could be found would this be a reasonable choice?? We are talking about RPM max of about 1000.? Will the sealed version hold up for this application???
Or maybe the double angular contact bearing like what is in my V-drive would be a good choice.? I do see those in sealed versions.? Like this:
If the axial load capacity on this is .5x the static load rating (as I saw referenced for deep groove ball bearings) then this 5208 is good for about 3500lbs.? Even at .3x its at 2200lbs which should be about a 4x margin with a 12kW motor?? It would not be difficult to make a housing block for one of these from aluminum.? I am thinking at least 1/2" of meat in the aluminum. How would that compare to an aluminum cased transmission like a ZF for strength?? They are housing thrust bearings in aluminum cases after all.? Here is a typical example:
These ucfl 207 bearing look interesting but that flange does not look like it holds/retains the bearing for thrust loads.? Maybe some of them do.? They need to in both directions or you need two of them, one on each side of the mounting plate.
I'll give the machining of the shaft a try.? I'll let you know how it goes.? From my experience with this lathe I think it is up to the task.? It is not a typical wee hobbyist machine.? I tend to be quite conservative in depth of cut.? And it's not that large a piece.?
Dan Pfeiffer
?
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On 2021-03-27 10:12 am, Carsten via groups.io wrote:
?
The double spherical roller bearing from grainger looks fine.
Even a smaller bearing than the shown will be fine for your 12KW motor...
?
I found an old thread in boatdesign.net. Please see reply #6 from the honorable Mike Johns:
?
I guess not feasible to make housings, when they already exist.
In the above thread, there are suggestions for housings too.
If in doubt, call SKF tech. dept. They are actually nice guys !
For ease of lubrication, they make these bearings in sealed versions too.
?
I would be happy by fixing the housing to the base plate properly aligned with shims (or ChockFast), and thus avoid a flexible coupling. (The belt drive should be flexible enough in itself.)
However, it takes a sturdy design of frame and base plate.
?
In my case, I will first try to modify my old saildrive to avoid a change to shaft drive (hellofwork).
?
Dan, from your photo, your lathe seems to be underpowered for this kind of shaft turning, IMHO.
?
?
On Friday, 26 March 2021, 23:07:08 GMT+8, Dan Pfeiffer <dan@...> wrote:
?
?
Some more on thrust bearing specifications...
My boat came with a Volvo 23HP diesel and a Walter RV-10D v-drive that contained the thrust bearing.?? The Walter RV-10 is specified for 2HP/100rpm or 48hp at 2400 (the max RPM on the Volvo).? So that's about double the capacity needed with the Volvo.? The thrust bearing in the unit can be seen in this drawing.? It is part number 15 (sorry for the silly long link...).?
It is a double row angular contact ball bearing type 5304.??
The bearings in the trailer hub I have been considering are L68149 and L44649 tapered roller bearings.??
I found some load specs on all these bearings in this document:
Basic Load Ratings (radial) ?? type?? - ??? ? ? ? ? ? Cr?? ? ? ? ?? ? - ?????? C0r ? 5304? - 24,600N (5530lbs) -? 15,000N (3372lbs)???? v-drive 68149 ? - 35,000N (7868lbs)? - 47,000 (10,566lbs) trailer hub large 44649? -? 27,600 (6204lbs)? - ? 32,000 (7193lbs) trailer hub small The second figure is a static load rating.? I also found this regarding axial loads in deep groove ball bearings: Deep groove ball bearings by nature of their design can carry axial loads either alone or in combination with radialloads. Axial load capacity of standard bearings is 0.5 times the Basic Static Load Rating, CO of that bearing. Smaller bearings should not be subject to a load greater than 0.25 times CO. Excessive axial loads can lead to serious reduction of bearing I am not sure how all this relates to the bearings in the trailer hub or v-drive but I am thinking the bearings in the trailer hub are at least as strong as the bearing in my v-drive. ? The trailer bearings are tapered roller bearings which I think are supposed to be better suited than the ball bearings for axial loads?? I don't know if that makes the trailer hub assembly a reasonable thrust bearing or not.? But at least the bearings are up to the task? ? And from this is it possible that the trailer hub is actually stronger as a thrust bearing unit than the v-drive that was running in my boat for 43 years? ??? I am sure there is more to it all than that.? But there are some numbers to consider.? But, another relevant consideration with the comparison between the angular contact bearings (v-drive) and tapered bearings (trailer hub) is friction.? The angular contact are lower friction and in a housing set up to run in oil rather than grease (my v drive is filled with 30wt oil) maybe they would be a better choice with less power lost between the electric motor and the prop.?? Now we just need an appropriate housing.? And that's really what the trailer hub was about.? Are the double roller spherical bearings something in between the roller and the angular contact?? I don't know the answers to these questions but I'll keep researching.? Dan Pfeiffer
On 2021-03-25 5:17 pm, Dan Pfeiffer wrote:
Carsten,? Thanks for the useful details. I have googled it.? Many hours spent.? I should have said I was a hobbyist, not a novice.? I don't have the knowledge on materials but I have some experience with the machining.? I have a very capable Sheldon 11" lathe with the appropriate tooling for this and a Bridgeport.? Worst case is I waste the 30-$50 on a blank for some useful practice.? It is a more challenging fabrication but worth a try I think.?
The spherical bearing is very interesting.? Maybe something like this:
Not crazy expensive but there is still the housing.? And that will need to have lubrication and seals.? I'll look further into it.?? Let us know when your housing design is ready.?
Yes the shaft will be in the engine room.? No exposure to sea water unless a hose bursts.? And I am on fresh water.?
Thanks, Dan Pfeiffer
?
On 2021-03-25 3:04 pm, Carsten via groups.io wrote:
Dan, 34CrNiMo6 is for hard working shafts, and easy to machine in properly sized lathe, given the right treatment is done before machining.
It is NOT stainless steel, and thus, not prone to "self-hardening".
Please google it.
?
I don't know your machining skills, but please contact a shaft machining shop (I did not say ANY machining shop) with your design at hand. This is definitely not a DIY novice job.
?
There seemailer wheel hub bearings lately in this forum, mostly triggered by the Thunderstruck (etc.) base plate designs.The shaft of a propeller has mostly only (bi-directional) axial forces, exept where we cons to be a tendency to choose standard trnect our belt pulley.
A hub bearing is meant to deal with radial forces, and some axial forces.
There are torsional forces too.
My suggestion is to use a double roller spherical bearing, set in a proper housing.
I contacted SKF (the inventor), and they recommended this bearing for this purpose.
(Hmm, maybe I should mass produce a range of housings ? ;-)
?
For corrosion, Dan, your shaft is to be in the engine/motor room, and not submerged (I hope), so it should only be protected for exposure to humidity, like a car body.
A clear Dinitrol spray will do fine.
Priming and painting looks nice, but ehh, not necessary for a simple shaft, right ?!
?
I hope this information will be useful.
?
?
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Hello,
I used this type of flexible shaft coupling. It's very easy to install and align. I still have vibrations but pretty sure it's either the cutlass, shaft or prop. Or all three, will try to fix that next haul out.
Regards,
Jesper?
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Re: Question about bus bar safety
Typo, hopefully obvious “48v or 12v”
Why do we still use asdf keyboard layouts on thumb driven mobile phones? Sigh.
toggle quoted message
Show quoted text
On Mar 27, 2021, at 10:57, Ryan Sweet via groups.io <ryan@...> wrote:
?For those of you that have 12v systems and 48v systems, is there a standard or convention for making it really clear that a given bus bar is 48v or 12c?
Mine are in very different places in the boat and I’ve taken to putting plastic covers over the top and then taping really big labels on them and updating the drawings kept on board (still I’m trying to think of someone working on the boat with no drawing and no history of the installation etc). I know they could and should check with the multimeter but I also feel an obligation to protect a future diy boat owner from themselves if they fail to do that. Hence, wondering if there is some convention.
|
Question about bus bar safety
For those of you that have 12v systems and 48v systems, is there a standard or convention for making it really clear that a given bus bar is 48v or 12c?
Mine are in very different places in the boat and I’ve taken to putting plastic covers over the top and then taping really big labels on them and updating the drawings kept on board (still I’m trying to think of someone working on the boat with no drawing and no history of the installation etc). I know they could and should check with the multimeter but I also feel an obligation to protect a future diy boat owner from themselves if they fail to do that. Hence, wondering if there is some convention.
|
Re: Ang.:Re: [electricboats] Material Choices and Thrust Bearings
On Thu, Mar 25, 2021 at 01:04 PM, Carsten wrote:
I contacted SKF (the inventor), and they recommended this bearing for this purpose.
(Hmm, maybe I should mass produce a range of housings ? ;-)
Carsten, That would actually be a great idea!? Not likely to a huge scale, but there are a few of us wanting to use a good thrust bearing / thrust plate solution. I would certainly buy one that was priced effectively and wasn't overbuilt for my purposes. I see the high end ones on the market, but I don't have a problem with noise -- at all.? And what I really want is a reliable solution that I can attach to my propeller shaft, then to a thrust plate I can attach to my motor mount / stay. Don't know the price range, but if the housing, attachments and bearings could be had for around $300 - $500, that would be fantastic.? Maybe even more. :-) Steve
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Re: Ang.:Re: [electricboats] Material Choices and Thrust Bearings
The double spherical roller bearing from grainger looks fine. Even a smaller bearing than the shown will be fine for your 12KW motor...
I found an old thread in boatdesign.net. Please see reply #6 from the honorable Mike Johns:
I guess not feasible to make housings, when they already exist. In the above thread, there are suggestions for housings too. If in doubt, call SKF tech. dept. They are actually nice guys !
For ease of lubrication, they make these bearings in sealed versions too.
I would be happy by fixing the housing to the base plate properly aligned with shims (or ChockFast), and thus avoid a flexible coupling. (The belt drive should be flexible enough in itself.)
However, it takes a sturdy design of frame and base plate.
In my case, I will first try to modify my old saildrive to avoid a change to shaft drive (hellofwork).
Dan, from your photo, your lathe seems to be underpowered for this kind of shaft turning, IMHO.
On Friday, 26 March 2021, 23:07:08 GMT+8, Dan Pfeiffer <dan@...> wrote:
Some more on thrust bearing specifications...
My boat came with a Volvo 23HP diesel and a Walter RV-10D v-drive that contained the thrust bearing.?? The Walter RV-10 is specified for 2HP/100rpm or 48hp at 2400 (the max RPM on the Volvo).? So that's about double the capacity needed with the Volvo.? The thrust bearing in the unit can be seen in this drawing.? It is part number 15 (sorry for the silly long link...).?
It is a double row angular contact ball bearing type 5304.??
The bearings in the trailer hub I have been considering are L68149 and L44649 tapered roller bearings.??
I found some load specs on all these bearings in this document:
Basic Load Ratings (radial) ?? type?? - ??? ? ? ? ? ? Cr?? ? ? ? ?? ? - ?????? C0r ? 5304? - 24,600N (5530lbs) -? 15,000N (3372lbs)???? v-drive 68149 ? - 35,000N (7868lbs)? - 47,000 (10,566lbs) trailer hub large 44649? -? 27,600 (6204lbs)? - ? 32,000 (7193lbs) trailer hub small The second figure is a static load rating.? I also found this regarding axial loads in deep groove ball bearings: Deep groove ball bearings by nature of their design can carry axial loads either alone or in combination with radialloads. Axial load capacity of standard bearings is 0.5 times the Basic Static Load Rating, CO of that bearing. Smaller bearings should not be subject to a load greater than 0.25 times CO. Excessive axial loads can lead to serious reduction of bearing I am not sure how all this relates to the bearings in the trailer hub or v-drive but I am thinking the bearings in the trailer hub are at least as strong as the bearing in my v-drive. ? The trailer bearings are tapered roller bearings which I think are supposed to be better suited than the ball bearings for axial loads?? I don't know if that makes the trailer hub assembly a reasonable thrust bearing or not.? But at least the bearings are up to the task? ? And from this is it possible that the trailer hub is actually stronger as a thrust bearing unit than the v-drive that was running in my boat for 43 years? ??? I am sure there is more to it all than that.? But there are some numbers to consider.? But, another relevant consideration with the comparison between the angular contact bearings (v-drive) and tapered bearings (trailer hub) is friction.? The angular contact are lower friction and in a housing set up to run in oil rather than grease (my v drive is filled with 30wt oil) maybe they would be a better choice with less power lost between the electric motor and the prop.?? Now we just need an appropriate housing.? And that's really what the trailer hub was about.? Are the double roller spherical bearings something in between the roller and the angular contact?? I don't know the answers to these questions but I'll keep researching.? Dan Pfeiffer
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On 2021-03-25 5:17 pm, Dan Pfeiffer wrote:
Carsten,? Thanks for the useful details. I have googled it.? Many hours spent.? I should have said I was a hobbyist, not a novice.? I don't have the knowledge on materials but I have some experience with the machining.? I have a very capable Sheldon 11" lathe with the appropriate tooling for this and a Bridgeport.? Worst case is I waste the 30-$50 on a blank for some useful practice.? It is a more challenging fabrication but worth a try I think.?
The spherical bearing is very interesting.? Maybe something like this:
Not crazy expensive but there is still the housing.? And that will need to have lubrication and seals.? I'll look further into it.?? Let us know when your housing design is ready.?
Yes the shaft will be in the engine room.? No exposure to sea water unless a hose bursts.? And I am on fresh water.?
Thanks, Dan Pfeiffer
?
On 2021-03-25 3:04 pm, Carsten via groups.io wrote:
Dan, 34CrNiMo6 is for hard working shafts, and easy to machine in properly sized lathe, given the right treatment is done before machining.
It is NOT stainless steel, and thus, not prone to "self-hardening".
Please google it.
?
I don't know your machining skills, but please contact a shaft machining shop (I did not say ANY machining shop) with your design at hand. This is definitely not a DIY novice job.
?
There seemailer wheel hub bearings lately in this forum, mostly triggered by the Thunderstruck (etc.) base plate designs.The shaft of a propeller has mostly only (bi-directional) axial forces, exept where we cons to be a tendency to choose standard trnect our belt pulley.
A hub bearing is meant to deal with radial forces, and some axial forces.
There are torsional forces too.
My suggestion is to use a double roller spherical bearing, set in a proper housing.
I contacted SKF (the inventor), and they recommended this bearing for this purpose.
(Hmm, maybe I should mass produce a range of housings ? ;-)
?
For corrosion, Dan, your shaft is to be in the engine/motor room, and not submerged (I hope), so it should only be protected for exposure to humidity, like a car body.
A clear Dinitrol spray will do fine.
Priming and painting looks nice, but ehh, not necessary for a simple shaft, right ?!
?
I hope this information will be useful.
?
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Re: Ang.:Re: [electricboats] Material Choices and Thrust Bearings
I will just give an interesting other point of view. Not sure if I can really recommend it, but for me it works. When I bought my boat it came with a 55hp yanmar. On the shaft just behind the gearbox was a ucfl 207 bearing mounted. It is not necessarily built mainly for axial forces, but it can handle them. Since it has been on this boat for 1500 engine hours and still working I decided to use the same bearing for the electric installation. I have the me1616 watercooled motor from thunderstruck running for half a year and until now it works perfectly for me. It makes the installation very easy, and if the bearing fails it's cheaper than the price of an impeller. Maybe worth a thought. Most of my motoring is done at low speeds (as probably most of us) I find the sweet spot at 30 to 40 amps which gives me 3.5 to 4 knots.?
Interested read nonetheless about all the bearings.?
Egbert
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On Sat, 27 Mar 2021, 04:56 Steven Borg, <steve@...> wrote:
Dan, Carsten and others,
I'm in somewhat of the same boat as Dan, considering the trailer hub.? I was (and still am) concerned about the forces -- trailer hubs are designed for PRIMARILY radial forces with a considerable amount of axial forces during turns. Here's my thinking...?
My motor can generate around 2000 pounds of axial thrust (100 HP). A 7,000 pound trailer hub is built for 3,500 pounds of radial thrust. Now, that's a gross miscalculation, I know. But it's a starting point. The hub can handle substantially higher loads, but those are the loads that the hub and bearings are rated for, assuming long term usage. Since the hub isn't built for axial loads, I went to dive into the bearings. Using the calculator at??I got this:?
Dynamic Load Rating for each bearing in the system, converted from kN to lb f, is conservatively 20,000 lb f and 13,000 lb f (forward and reverse). Now, according to a calculation I found online Force = x*radial +y*axial where x and y are scaling factors. x is generally 1 and y is provided by the bearing manufacturer. As best I can tell, and there was a lot of confusion in my mind, for the bearings above the y is 1.8 (which implies that they hand radial forces better than axial forces). Now, another thing I read says that x can be .67 is the axial forces are much bigger than radial forces.? So, that implies that for the the bigger bearing we have: 20,000 = 0.67*axial + 1.8*radial.? Now, if I assume that I have already taken that into account with the .67 and 1.8, then I'm at about 1/3 as strong, and that makes sense. In that case, with limited radial forces, the bearing can run at normal usage with around 1,000 lb f and get it's full lifespan. The bearings themselves can take an order of magnitude more force for periods of time without issue (like when a loaded trailer goes over a speed bump), and I'll be running at or below 1000 pounds of force in normal operation. (Higher than that will take too much battery drain for my liking.)
Now, a proper bearing, built for axial thrust would, for less money, take 5-6 times as much axial force with ease.? BUT, and here's my biggest concern, I don't know how to engineer one of those effectively. And my fear is that my jerry-rigged solution would be less effective in reality than it would be in theory. And a trailer hub, despite its many issues, is engineered by someone who has to make sure they will survive being used aggressively on dirt roads and the like. That's what's keeping me in the trailer hub space, at least for now.
Finally, slamming the boat into reverse is my #1 expected hard usage. If I put all 2,000 lb f that I can produce into the water, I'm over the normal use limits considerably, but nowhere near the 20-50,000 lb-f limits to deform the bearings or cause damage -- just experiencing excess wear.
Last thought. I'm only really pushing the boat at 300 lb-f so there's a pretty big margin there for general use, and I'm a very light user, so there's that.? Still, everything on the boat is built to last and built at the top end (for 30 years ago). I hate to 'hack' something together, but I also want to be sure I'm using components that are tested.?
That's my current thinking, Carsten (and Dan).
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Re: Ang.:Re: [electricboats] Material Choices and Thrust Bearings
Dan, Carsten and others,
I'm in somewhat of the same boat as Dan, considering the trailer hub.? I was (and still am) concerned about the forces -- trailer hubs are designed for PRIMARILY radial forces with a considerable amount of axial forces during turns. Here's my thinking...?
My motor can generate around 2000 pounds of axial thrust (100 HP). A 7,000 pound trailer hub is built for 3,500 pounds of radial thrust. Now, that's a gross miscalculation, I know. But it's a starting point. The hub can handle substantially higher loads, but those are the loads that the hub and bearings are rated for, assuming long term usage. Since the hub isn't built for axial loads, I went to dive into the bearings. Using the calculator at??I got this:?
Dynamic Load Rating for each bearing in the system, converted from kN to lb f, is conservatively 20,000 lb f and 13,000 lb f (forward and reverse). Now, according to a calculation I found online Force = x*radial +y*axial where x and y are scaling factors. x is generally 1 and y is provided by the bearing manufacturer. As best I can tell, and there was a lot of confusion in my mind, for the bearings above the y is 1.8 (which implies that they hand radial forces better than axial forces). Now, another thing I read says that x can be .67 is the axial forces are much bigger than radial forces.? So, that implies that for the the bigger bearing we have: 20,000 = 0.67*axial + 1.8*radial.? Now, if I assume that I have already taken that into account with the .67 and 1.8, then I'm at about 1/3 as strong, and that makes sense. In that case, with limited radial forces, the bearing can run at normal usage with around 1,000 lb f and get it's full lifespan. The bearings themselves can take an order of magnitude more force for periods of time without issue (like when a loaded trailer goes over a speed bump), and I'll be running at or below 1000 pounds of force in normal operation. (Higher than that will take too much battery drain for my liking.)
Now, a proper bearing, built for axial thrust would, for less money, take 5-6 times as much axial force with ease.? BUT, and here's my biggest concern, I don't know how to engineer one of those effectively. And my fear is that my jerry-rigged solution would be less effective in reality than it would be in theory. And a trailer hub, despite its many issues, is engineered by someone who has to make sure they will survive being used aggressively on dirt roads and the like. That's what's keeping me in the trailer hub space, at least for now.
Finally, slamming the boat into reverse is my #1 expected hard usage. If I put all 2,000 lb f that I can produce into the water, I'm over the normal use limits considerably, but nowhere near the 20-50,000 lb-f limits to deform the bearings or cause damage -- just experiencing excess wear.
Last thought. I'm only really pushing the boat at 300 lb-f so there's a pretty big margin there for general use, and I'm a very light user, so there's that.? Still, everything on the boat is built to last and built at the top end (for 30 years ago). I hate to 'hack' something together, but I also want to be sure I'm using components that are tested.?
That's my current thinking, Carsten (and Dan).
|
Hello,
I am poking around different shaft coupling ideas.? Has anyone used
anything like this to reduce noise, alignment, vibration?
Cheers,
--
|
Jeff LaCoursiere
STRATUSTALK, INC. / CTO
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+1
703.496.4990 x108 |
Mobile: |
+1
815.546.6599 |
Email: |
jeff@...
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Website: |
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Address: |
One
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13th Floor
Reston, VA 20190 |
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? ? ? |
-- Jeff LaCoursiere s/v Angels Quest St Thomas USVI
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Re: Ang.:Re: Ang.:Re: [electricboats] Sizing motor for 45-50’ boats
Carsten,
Thank you!? I've found good bearings, but have no idea how to get them into a usable configuration. I've sketched out several ideas, but, unlike Dan, I don't have a lathe.? I agree that it would potentially be both better looking and stronger to not use a trailer hub. I'm still considering building my own, but I'm also still considering the hub.? Let me go in further depth back on the other thread.
:-) Steve
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On Thu, Mar 25, 2021 at 01:00 PM, Carsten wrote:
Nice setup, Steve !
You wrote :??"places the biggest bearing where it will take the forward thrust".
Ther might be situations, where you will need the use of full reverse (when anchoring), but unfortunately most often in emergency situations.
I suggest that you make your thrust bearing equally strong dimensioned for both forward and reverse.
I do not recommend a trailer hub bearing to be used as a propeller shaft thrust bearing. Cheap, yes, but not the best for this purpose.
?
We happily spend 1000 hours of DIY design? and 10-30K $ of cash on our project,? but - save on the important thrust bearing... ?!? Nonono, and no !
?
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Re: Ang.:Re: [electricboats] Material Choices and Thrust Bearings
Some more on thrust bearing specifications...
My boat came with a Volvo 23HP diesel and a Walter RV-10D v-drive that contained the thrust bearing.?? The Walter RV-10 is specified for 2HP/100rpm or 48hp at 2400 (the max RPM on the Volvo).? So that's about double the capacity needed with the Volvo.? The thrust bearing in the unit can be seen in this drawing.? It is part number 15 (sorry for the silly long link...).?
It is a double row angular contact ball bearing type 5304.??
The bearings in the trailer hub I have been considering are L68149 and L44649 tapered roller bearings.??
I found some load specs on all these bearings in this document:
Basic Load Ratings (radial) ?? type?? - ??? ? ? ? ? ? Cr?? ? ? ? ?? ? - ?????? C0r ? 5304? - 24,600N (5530lbs) -? 15,000N (3372lbs)???? v-drive 68149 ? - 35,000N (7868lbs)? - 47,000 (10,566lbs) trailer hub large 44649? -? 27,600 (6204lbs)? - ? 32,000 (7193lbs) trailer hub small The second figure is a static load rating.? I also found this regarding axial loads in deep groove ball bearings: Deep groove ball bearings by nature of their design can carry axial loads either alone or in combination with radialloads. Axial load capacity of standard bearings is 0.5 times the Basic Static Load Rating, CO of that bearing. Smaller bearings should not be subject to a load greater than 0.25 times CO. Excessive axial loads can lead to serious reduction of bearing I am not sure how all this relates to the bearings in the trailer hub or v-drive but I am thinking the bearings in the trailer hub are at least as strong as the bearing in my v-drive. ? The trailer bearings are tapered roller bearings which I think are supposed to be better suited than the ball bearings for axial loads?? I don't know if that makes the trailer hub assembly a reasonable thrust bearing or not.? But at least the bearings are up to the task? ? And from this is it possible that the trailer hub is actually stronger as a thrust bearing unit than the v-drive that was running in my boat for 43 years? ??? I am sure there is more to it all than that.? But there are some numbers to consider.? But, another relevant consideration with the comparison between the angular contact bearings (v-drive) and tapered bearings (trailer hub) is friction.? The angular contact are lower friction and in a housing set up to run in oil rather than grease (my v drive is filled with 30wt oil) maybe they would be a better choice with less power lost between the electric motor and the prop.?? Now we just need an appropriate housing.? And that's really what the trailer hub was about.? Are the double roller spherical bearings something in between the roller and the angular contact?? I don't know the answers to these questions but I'll keep researching.? Dan Pfeiffer
toggle quoted message
Show quoted text
On 2021-03-25 5:17 pm, Dan Pfeiffer wrote:
Carsten,? Thanks for the useful details. I have googled it.? Many hours spent.? I should have said I was a hobbyist, not a novice.? I don't have the knowledge on materials but I have some experience with the machining.? I have a very capable Sheldon 11" lathe with the appropriate tooling for this and a Bridgeport.? Worst case is I waste the 30-$50 on a blank for some useful practice.? It is a more challenging fabrication but worth a try I think.?
The spherical bearing is very interesting.? Maybe something like this:
Not crazy expensive but there is still the housing.? And that will need to have lubrication and seals.? I'll look further into it.?? Let us know when your housing design is ready.?
Yes the shaft will be in the engine room.? No exposure to sea water unless a hose bursts.? And I am on fresh water.?
Thanks, Dan Pfeiffer
?
On 2021-03-25 3:04 pm, Carsten via groups.io wrote:
Dan, 34CrNiMo6 is for hard working shafts, and easy to machine in properly sized lathe, given the right treatment is done before machining.
It is NOT stainless steel, and thus, not prone to "self-hardening".
Please google it.
?
I don't know your machining skills, but please contact a shaft machining shop (I did not say ANY machining shop) with your design at hand. This is definitely not a DIY novice job.
?
There seemailer wheel hub bearings lately in this forum, mostly triggered by the Thunderstruck (etc.) base plate designs.The shaft of a propeller has mostly only (bi-directional) axial forces, exept where we cons to be a tendency to choose standard trnect our belt pulley.
A hub bearing is meant to deal with radial forces, and some axial forces.
There are torsional forces too.
My suggestion is to use a double roller spherical bearing, set in a proper housing.
I contacted SKF (the inventor), and they recommended this bearing for this purpose.
(Hmm, maybe I should mass produce a range of housings ? ;-)
?
For corrosion, Dan, your shaft is to be in the engine/motor room, and not submerged (I hope), so it should only be protected for exposure to humidity, like a car body.
A clear Dinitrol spray will do fine.
Priming and painting looks nice, but ehh, not necessary for a simple shaft, right ?!
?
I hope this information will be useful.
?
|