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 !

?

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.

?

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.

P? fre., den 26. mar. 2021 klokken 1:45, Dan Pfeiffer

<dan@...> skrev:

Carsten,? That'll do.? Always good to know.? Thanks.

At first glance to my novice eye the specs the material you specified looks fairly tough to machine.? Is the comparative machining issue with SS due to work hardening??

What would you do to protect the alloy steel shaft from corrosion??


Dan Pfeiffer

?

On 2021-03-23 4:09 pm, Carsten via groups.io wrote:

?

Educated machinist at a nuclear test facility in Denmark.

Worked as production planner and programmer of CNC multiple axis lathes and milling machines for 18 years

Switched to large marine producers, writing procedures for manufacturing, and tested production methods at suppliers

Worked in Asia for 10 years, educating and teaching many of the production facilities of large Diesel engine manufacturers in South Korea and China, and assembly of engines at the shipyards

Made the crankshaft production in China feasible for them

?

Now retired (and actually tired of chinese taking over everything (because of me, partly)).

?

Is that ok for you, Dan ?

?

In short, SS is not easily machined.

Go for my selection, then you'll have an easy time at your lathe.

I'm sure that you can look up the equivalent of my material in a comparison table.

?

Cheers !

?

?

On Wednesday, 24 March 2021, 04:23:21 GMT+8, Dan Pfeiffer <dan@...> wrote:

?

?

>>Hi, Dan

>>I will suggest 34CrNiMo6 alloy for your shaft.

>>>

>>>On Friday, 19 March 2021, 07:07:01 GMT+8, Dan Pfeiffer <dan@...> wrote:

>>>Carsten, You mentioned that I should not bother with stainless steel for my small output shaft.? What would you suggest for that instead??

I found this info:


Is a 4340 a similar alloy? I can get that from McMaster.? Cost is the about the same as SS.? How hard will it machine in my lathe??? I was prepared to machine the SS.? Will this be tougher??

Also, I am figuring you have some background in all this??

Thanks, Dan Pfeiffer

?

?

?

P? fre., den 26. mar. 2021 klokken 1:45, Dan Pfeiffer

<dan@...> skrev:

Carsten,? That'll do.? Always good to know.? Thanks.

At first glance to my novice eye the specs the material you specified looks fairly tough to machine.? Is the comparative machining issue with SS due to work hardening??

What would you do to protect the alloy steel shaft from corrosion??


Dan Pfeiffer

?

On 2021-03-23 4:09 pm, Carsten via groups.io wrote:

?

Educated machinist at a nuclear test facility in Denmark.

Worked as production planner and programmer of CNC multiple axis lathes and milling machines for 18 years

Switched to large marine producers, writing procedures for manufacturing, and tested production methods at suppliers

Worked in Asia for 10 years, educating and teaching many of the production facilities of large Diesel engine manufacturers in South Korea and China, and assembly of engines at the shipyards

Made the crankshaft production in China feasible for them

?

Now retired (and actually tired of chinese taking over everything (because of me, partly)).

?

Is that ok for you, Dan ?

?

In short, SS is not easily machined.

Go for my selection, then you'll have an easy time at your lathe.

I'm sure that you can look up the equivalent of my material in a comparison table.

?

Cheers !

?

?

On Wednesday, 24 March 2021, 04:23:21 GMT+8, Dan Pfeiffer <dan@...> wrote:

?

?

>>Hi, Dan

>>I will suggest 34CrNiMo6 alloy for your shaft.

>>>

>>>On Friday, 19 March 2021, 07:07:01 GMT+8, Dan Pfeiffer <dan@...> wrote:

>>>Carsten, You mentioned that I should not bother with stainless steel for my small output shaft.? What would you suggest for that instead??

I found this info:


Is a 4340 a similar alloy? I can get that from McMaster.? Cost is the about the same as SS.? How hard will it machine in my lathe??? I was prepared to machine the SS.? Will this be tougher??

Also, I am figuring you have some background in all this??

Thanks, Dan Pfeiffer

?

P? fre., den 26. mar. 2021 klokken 1:14, Steven Borg

<steve@...> skrev:

Amazing thoughts! Thank you so much for all this information. I'm plodding along an slowly progressing.? Here are my existing thoughts. Dan, I'm planning on riffing from your plans, spinning the engine to the other side, and doing a few other things.

Here’s my latest thinking for getting my 55’ sailboat on electric. It’s based on all the wonderful feedback here!

After much thought, I’ve decided against using a transmission and am going to go with a pulley system. It’s just simpler, even though I lose the ability to have a neutral (which would allow my auxiliary shaft to be used for an emergency pump). That decision was driven by the advice of the good people on this list. Thank you!

However, I’m planning on mounting my engine the opposite direction of everyone on this list, and I thought I’d explain why, in hopes of getting feedback from folks.

Here’s a very, very ugly diagram, not to scale, made by cutting and pasting.

?

I’m going to go with off the shelf components where possible. That’s one reason for putting the Spindle facing forward – I won’t have to machine it, and it puts the larger bearings where they will accept the forward thrust (which for me is more common).

Initial (potentially incorrect) thoughts:

• Put thrust plate AFTER large belt spindle – given the limited forward and backward slip from the Hub, I don’t think that will cause issues with the belt slipping off (1 ?” belt, I believe)
• Orient the Hub and Spindle with the ‘wheel’ side facing fore – this means no metal working for me, places the biggest bearing where it will take the forward thrust and simplifies installation
• Orient the motor on the fore side of the mounting plate – this is necessary to get the belt and gears on the same side, plus I have more room on this side of the plate if I decide to mount the plate, motor and gears at a 45 degree angle to starboard to get more space in the engine room
• Use the 6000 lb hub and spindle – this gives me the capability to support more thrust.?
  • Rule of thumb of 20 lbs force for every HP gives me 2000 lbs force, which is within tolerances for this hub and associated bearing.
  • Hub:?
  • #42 Spindle:?
• Use a motorcycle kit for my sprockets and belts – I’m looking for a 5 to 1 reduction, and that’s really hard to find on Grainger without having a really small engine sprocket. The Zero motorcycle is an electric motorcycle that provides torque only slightly less than the Hyper-9, so I thought it would be a good solution. It’s made for providing power transmission and has a reduction ration of 4.5 to 1 which is good enough (20 teeth to 90 teeth).
• Tighten with one or two idler pulleys – not sure if I will have enough space to tighten much, so will likely need to get belt pretty close to the right size if I even change the engine sprocket to change the reduction ratio.
  • In the worst case, I can have one pull in, and another pull out, but that's not ideal
• Battery box will be custom built, as I have 48 Lishen (similar to Eve) 280AH batteries that will take up a lot of room. They will end up on the stays with supports to allow walking on them when I drop into the engine compartment.? Should I call that a motor compartment now? ;-)

Thanks so much for everyone on this list. Dan, I'm really happy you started this thread, and Carsten, you have so much wonderful knowledge. And everyone else has such valuable experience and insight.? Thank you!

?

Educated machinist at a nuclear test facility in Denmark.

Worked as production planner and programmer of CNC multiple axis lathes and milling machines for 18 years

Switched to large marine producers, writing procedures for manufacturing, and tested production methods at suppliers

Worked in Asia for 10 years, educating and teaching many of the production facilities of large Diesel engine manufacturers in South Korea and China, and assembly of engines at the shipyards

Made the crankshaft production in China feasible for them

?

Now retired (and actually tired of chinese taking over everything (because of me, partly)).

?

Is that ok for you, Dan ?

?

In short, SS is not easily machined.

Go for my selection, then you'll have an easy time at your lathe.

I'm sure that you can look up the equivalent of my material in a comparison table.

?

Cheers !

?

?

On Wednesday, 24 March 2021, 04:23:21 GMT+8, Dan Pfeiffer <dan@...> wrote:

?

?

>>Hi, Dan

>>I will suggest 34CrNiMo6 alloy for your shaft.

>>>

>>>On Friday, 19 March 2021, 07:07:01 GMT+8, Dan Pfeiffer <dan@...> wrote:

>>>Carsten, You mentioned that I should not bother with stainless steel for my small output shaft.? What would you suggest for that instead??

I found this info:


Is a 4340 a similar alloy? I can get that from McMaster.? Cost is the about the same as SS.? How hard will it machine in my lathe??? I was prepared to machine the SS.? Will this be tougher??

Also, I am figuring you have some background in all this??

Thanks, Dan Pfeiffer

?

On Mar 16, 2021, at 3:01 PM, Steven Borg <steve@...> wrote:

?Dan, this is an incredibly useful reply! Thank you!!

I really like your approach, especially since I don't have an intermediate location to put an inline thrust bearing. (Although it wouldn't be hard to fiberglass one in, it would be difficult to get to when I need to maintain the bearings, etc.)? Plus, as you've mentioned, the cost to Python is substantially higher than building my own integrated to the engine plate (like the Thunderstruck solution).??

Using the eTrailer solution looks like an excellent plan for a DIY solution. I'm trying to evaluate how much thrust I'll need to account for and which solution I should use. The Hyper-9 HV is a pretty beefy motor, and my prop is 24" with a 24" pitch (potentially reducing to 14"-16" when I pull her out of the water next).?

How much thrust are you planning for with your solution?? I notice you're planning to have a non-threaded section after the threads. Is that to attach the belt pulley? I didn't quite understand that part of your solution, but maybe I need to just do some more thinking.

For the belt drive system, I'm considering adding a 3rd pulley for tensioning. Would that be a bad idea?? The motor is heavy, and I'd like to mount it in predrilled holes, rather than make it adjustable. Also, since my propeller shaft will go directly to the motor, I'll need to align it relatively precisely, so don't want to use the thrust bearing / prop shaft assembly for tensioning.? (I suppose this is one reason to use the Python solution...? ;-))

Once again, HUGE thanks, Dan!? This was AMAZINGLY helpful!

:-)
Steve

?

Dan,

?

I have reviewed your drawings. Very interesting, a hybrid boat !

?

When you are using a toothbelt drive, you actually don't need a Drivesaver, as the toothbelt will slip or break in a crash-stop situation. A new belt is far easier (and cheaper) to replace than a Drivesaver coupling.

The inertia in an electric motor (the rotating mass) is far less than by a diesel engine with a big flywheel, and you have no gearbox anymore to worry about.

?

The position of the ME1616 motor is almost free to choose, meaning that you can add a pulley to the shaft almost anywhere until you reach the sterndrive. The distance from shaft centerline to motor centerline is also only determined of the toothbelt length. You don't HAVE to place it in one common frameplate.

?

If you make the motor base adjustable, it is easy to change the belt.

If you make the frameplate with fixed driveshaft and motor shaft, like on your drawing, you likely will add an adjustable bearing roller to adjust the tension of the belt (same like in a car engine, for a camshaft toothbelt). Very handy too, for changes of pulleys for reduction ratio. (The roller must roll on the flat side of the belt, of course.)

I guess a complete roller kit for a car is rather inexpensive.

?

Why use aluminum for the construction?

I know that it easier to cut a thread and drill a hole in aluminum than in steel.

But :

Steel channels and steel plates are much easier to repair if you make a mistake, or something should be re-positioned.

Aluminum welding is no fun, and threads cut in steel are much stronger. You use Helicoils in aluminium constructions, if threads shall be strong and lasting. That requires special tools, so - not for a DIY mechanic.

If you need something done, any workshop in any port can weld steel, and can always find a standard machine tap in the dirty drawers.

?

I would say, that an ME1616 used as a generator might be shooting sparrows with a cannon - an expensive solution. Balmar have some 48V alternators, you can check them out.

?

How is your plan for cooling of the ME1616 for the shaft ? (I assume that you will make a common system for the Kubota and the ME1616.)

?

What kind of battery bank is in your plans ?

?

Do you have a photo of the shaft and of the engine room, as it is now ?

?

?

Cheers,

Carsten

?

?

?

Dan,

?

I have reviewed your drawings. Very interesting, a hybrid boat !

?

When you are using a toothbelt drive, you actually don't need a Drivesaver, as the toothbelt will slip or break in a crash-stop situation. A new belt is far easier (and cheaper) to replace than a Drivesaver coupling.

The inertia in an electric motor (the rotating mass) is far less than by a diesel engine with a big flywheel, and you have no gearbox anymore to worry about.

?

The position of the ME1616 motor is almost free to choose, meaning that you can add a pulley to the shaft almost anywhere until you reach the sterndrive. The distance from shaft centerline to motor centerline is also only determined of the toothbelt length. You don't HAVE to place it in one common frameplate.

?

If you make the motor base adjustable, it is easy to change the belt.

If you make the frameplate with fixed driveshaft and motor shaft, like on your drawing, you likely will add an adjustable bearing roller to adjust the tension of the belt (same like in a car engine, for a camshaft toothbelt). Very handy too, for changes of pulleys for reduction ratio. (The roller must roll on the flat side of the belt, of course.)

I guess a complete roller kit for a car is rather inexpensive.

?

Why use aluminum for the construction?

I know that it easier to cut a thread and drill a hole in aluminum than in steel.

But :

Steel channels and steel plates are much easier to repair if you make a mistake, or something should be re-positioned.

Aluminum welding is no fun, and threads cut in steel are much stronger. You use Helicoils in aluminium constructions, if threads shall be strong and lasting. That requires special tools, so - not for a DIY mechanic.

If you need something done, any workshop in any port can weld steel, and can always find a standard machine tap in the dirty drawers.

?

I would say, that an ME1616 used as a generator might be shooting sparrows with a cannon - an expensive solution. Balmar have some 48V alternators, you can check them out.

?

How is your plan for cooling of the ME1616 for the shaft ? (I assume that you will make a common system for the Kubota and the ME1616.)

?

What kind of battery bank is in your plans ?

?

Do you have a photo of the shaft and of the engine room, as it is now ?

?

?

Cheers,

Carsten

?

?

?

Thanks, Dan !

?

Save your money on stainless (exept the shaft part from cutless bearing to prop).

You have an inboard, and mechanical properties of good ol "rusty" steel are usually better than ss.

?

Could you please provide a sketch of your setup ?

It seems very interesting !

?

Carsten

?

?

On Tuesday, 16 March 2021, 23:54:19 GMT+8, Dan Pfeiffer <dan@...> wrote:

?

?

(sorry if this is a repeat - I posted it 8hrs ago and it never showed up)

I have also spent a lot of time looking for thrust bearing options.? That Python Drive looks like a great solution where there is room to fit it.? Looks like it will leave some room in the wallet too.?

Thunderstruck uses a trailer hub with tapered roller bearings.? It's a good simple and inexpensive solution for small setups (<30hp?).?? I think this is the hub they use:



One issue with these is setting the pre-load on the bearings.? If you have changed the wheel bearings on a car you know what this is about.? Thunderstruck does it by using a fixed collar and bushing on the prop side of the bearing and another bushing on the other side that is held in place by the tapered bushing that holds the toothed belt for the reduction gear pulley.? It's a simple setup with only a few parts and some simple machining on the shaft.

I am fabricating my own belt drive reduction gear for my boat (12kW motor) and I am going to use a trailer hub that's one size larger and available in stainless steel (with a price premium of course).? This is what I am using:


I am going to use a threaded split collar on the shaft to set the pre-load on the bearing.? My shaft will be a more complicated machining (including a threaded section) but I think it will be a better way to set and hold the pre-load on the bearings.?? The two parts I have to make are the shaft and the bushing.? Both will be stainless steel.? The hub will remain stock with no machining.? The bearings are standard hub bearings you can get anywhere.?? All the parts except the bearings will be stainless steel.? And the bearings will be in the grease.? The bushing will have the OD sized to fit the grease seal on the hub that takes the place of the standard cap when it is used on a wheel.? It's a standard grease seal but I had to hunt a bit to sort out fitting it in the hub.?

This could easily be scaled up for larger applications.?? These hubs come in at least two larger sizes in stainless.?

The bearing, reduction gear assembly, and motor will mount to an aluminum plate similar to what Thunderstruck does.? I was going to use a piece of c-channel and that would work well but I wanted more flexibility in the pulley sizing to be better able to fine tune the reduction ratio and the c-channel limits the diameter of the gear pulley a bit.? I am still sorting that part out but I am aiming for about 3:1 for the reduction.? The world of timing belts and pulleys is vast and has been difficult to get a handle on so far.?


Dan Pfeiffer

?

On 2021-03-15 11:29 pm, Carsten via groups.io wrote:

Of course you'll need a double bearing for axial loads in forward and reverse...

P? tir., den 16. mar. 2021 klokken 10:47, Carsten via groups.io

<Carstensemail@...> skrev:

Hi, Steve

?

Consider to make your thrust bearing with a high quality spherical roller thrust bearing, eg. of SKF brand. This can accept torsional forces much better than ball thrust bearings.

Then you don't need the expensive solutions with a lot of rubber (which needs care and replacement when worn).

?

The tooth belt drive (not V-belt, which introduces higher radial forces to the shaft) can be mounted either before or after the thrust bearing.

The housing for the thrust bearing should best be mounted close to the cutlass bearing, to minimize torsional bending of a long shaft.

?

Could you please post some photos of your existing setup of the shaft and cutlass ?

?

Have you considered which prop you will use for your new setup ?

Going electric has a lot of torque at low revs, which is very useful during maneuvering, so the prop should have less pitch and larger diameter, imho.

?

Carsten

?

?

P? tir., den 16. mar. 2021 klokken 4:52, Steven Borg

<steve@...> skrev:

I'm in the process of planning and installing a Hyper-9 motor at 154V with a battery bank of 48 280Ah 3.2V LiFePO4 batteries I received from China. The motor is?rated to be plenty powerful to replace my 100 HP Diesel (which has been removed).? I'll keep everyone posted when it's installed.

In the meantime, I have a related question (maybe for ChristopherH?) around thrust bearings.? I've decided to use a belt drive (like the photos above, but for a single motor and gear.? But without the transmission I had planned on using (with integrated thrust bearings), I'm going to need to anchor the propshaft to the boat.??

Christopher, what inline thrust bearing did you use?? I'm trying to determine if I should build out a thrust bearing somewhere along the prop shaft, or whether I should integrate the thrust bearing into the engine mount, either before or after the belt pulley driving the shaft.? Also, if there's a pre-made thrust bearing for boats, I can't seem to find them (except large ones for giant ships). Does anyone know what they'd be called, so I can search for them.? (Yes, this is an embarrassing, totally newbie, question to ask, but I just can't seem to find them, so have been debating whether to just engineer my own from bearings off Granger or McMaster-Carr).

I'm not sure those questions even made sense, but that's where I'm starting...? Still trying to figure out the best way to get this done!??

This has been an amazing thread!? Thank you!

?

?

Thanks, Dan !

?

Save your money on stainless (exept the shaft part from cutless bearing to prop).

You have an inboard, and mechanical properties of good ol "rusty" steel are usually better than ss.

?

Could you please provide a sketch of your setup ?

It seems very interesting !

?

Carsten

?

?

On Tuesday, 16 March 2021, 23:54:19 GMT+8, Dan Pfeiffer <dan@...> wrote:

?

?

(sorry if this is a repeat - I posted it 8hrs ago and it never showed up)

I have also spent a lot of time looking for thrust bearing options.? That Python Drive looks like a great solution where there is room to fit it.? Looks like it will leave some room in the wallet too.?

Thunderstruck uses a trailer hub with tapered roller bearings.? It's a good simple and inexpensive solution for small setups (<30hp?).?? I think this is the hub they use:



One issue with these is setting the pre-load on the bearings.? If you have changed the wheel bearings on a car you know what this is about.? Thunderstruck does it by using a fixed collar and bushing on the prop side of the bearing and another bushing on the other side that is held in place by the tapered bushing that holds the toothed belt for the reduction gear pulley.? It's a simple setup with only a few parts and some simple machining on the shaft.

I am fabricating my own belt drive reduction gear for my boat (12kW motor) and I am going to use a trailer hub that's one size larger and available in stainless steel (with a price premium of course).? This is what I am using:


I am going to use a threaded split collar on the shaft to set the pre-load on the bearing.? My shaft will be a more complicated machining (including a threaded section) but I think it will be a better way to set and hold the pre-load on the bearings.?? The two parts I have to make are the shaft and the bushing.? Both will be stainless steel.? The hub will remain stock with no machining.? The bearings are standard hub bearings you can get anywhere.?? All the parts except the bearings will be stainless steel.? And the bearings will be in the grease.? The bushing will have the OD sized to fit the grease seal on the hub that takes the place of the standard cap when it is used on a wheel.? It's a standard grease seal but I had to hunt a bit to sort out fitting it in the hub.?

This could easily be scaled up for larger applications.?? These hubs come in at least two larger sizes in stainless.?

The bearing, reduction gear assembly, and motor will mount to an aluminum plate similar to what Thunderstruck does.? I was going to use a piece of c-channel and that would work well but I wanted more flexibility in the pulley sizing to be better able to fine tune the reduction ratio and the c-channel limits the diameter of the gear pulley a bit.? I am still sorting that part out but I am aiming for about 3:1 for the reduction.? The world of timing belts and pulleys is vast and has been difficult to get a handle on so far.?


Dan Pfeiffer

?

On 2021-03-15 11:29 pm, Carsten via groups.io wrote:

Of course you'll need a double bearing for axial loads in forward and reverse...

P? tir., den 16. mar. 2021 klokken 10:47, Carsten via groups.io

<Carstensemail@...> skrev:

Hi, Steve

?

Consider to make your thrust bearing with a high quality spherical roller thrust bearing, eg. of SKF brand. This can accept torsional forces much better than ball thrust bearings.

Then you don't need the expensive solutions with a lot of rubber (which needs care and replacement when worn).

?

The tooth belt drive (not V-belt, which introduces higher radial forces to the shaft) can be mounted either before or after the thrust bearing.

The housing for the thrust bearing should best be mounted close to the cutlass bearing, to minimize torsional bending of a long shaft.

?

Could you please post some photos of your existing setup of the shaft and cutlass ?

?

Have you considered which prop you will use for your new setup ?

Going electric has a lot of torque at low revs, which is very useful during maneuvering, so the prop should have less pitch and larger diameter, imho.

?

Carsten

?

?

P? tir., den 16. mar. 2021 klokken 4:52, Steven Borg

<steve@...> skrev:

I'm in the process of planning and installing a Hyper-9 motor at 154V with a battery bank of 48 280Ah 3.2V LiFePO4 batteries I received from China. The motor is?rated to be plenty powerful to replace my 100 HP Diesel (which has been removed).? I'll keep everyone posted when it's installed.

In the meantime, I have a related question (maybe for ChristopherH?) around thrust bearings.? I've decided to use a belt drive (like the photos above, but for a single motor and gear.? But without the transmission I had planned on using (with integrated thrust bearings), I'm going to need to anchor the propshaft to the boat.??

Christopher, what inline thrust bearing did you use?? I'm trying to determine if I should build out a thrust bearing somewhere along the prop shaft, or whether I should integrate the thrust bearing into the engine mount, either before or after the belt pulley driving the shaft.? Also, if there's a pre-made thrust bearing for boats, I can't seem to find them (except large ones for giant ships). Does anyone know what they'd be called, so I can search for them.? (Yes, this is an embarrassing, totally newbie, question to ask, but I just can't seem to find them, so have been debating whether to just engineer my own from bearings off Granger or McMaster-Carr).

I'm not sure those questions even made sense, but that's where I'm starting...? Still trying to figure out the best way to get this done!??

This has been an amazing thread!? Thank you!

?