From what I have read, one issue with BLDC motors at low RPM involves "cogging", so it seems a GR would still be very much on the plate. What I am really curious about, though, is this:
(and this may not be the proper forum for this discussion, so I mention it only in passing!)
If I were to embark on a project such as developing a gear reduction such as John's or Robert's, I would first model it and then make a 3D print of my design for proving before committing the time and effort in doing the machine work. But then if I were to use some high strength nylon or carbon filled filament to produce my design, maybe that alone would be adequate, or at least adequate to the degree that I could use it to aid in machining the final item.
That workflow is what I would use if I were to embark on the ELS path. I think some of the aluminum parts could be 3D printed and then perhaps replaced at some point in the future, once everything is up and running.
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I have the s on my Clausing 8520 mill (21/2" x 6" pulleys) and on my Delta 14" Bandsaw (21/2" x 16" pulleys) I haves lots of torque even down to 100 rpm on the motor. I can stall the bandsaw applying too much pressure.
I have two more of the same motors waiting to go on my lathes.
On Tue, Aug 13, 2019 at 10:24 AM CLevinski < clevinski@...> wrote: Hi, Ralph,
I realize that there would have to be gear reduction to at least a 2500 RPM spindle speed (assuming the desire to duplicate the original mini-lathe speed), but what I was speculating about was whether a Brushless DC motor, geared to 2500 RPM, would produce the same torque as a brushed DC motor geared to 1250 RPM.? I don't know; I have no experience with BLDC motors in lathes.? But the fact it they are used in the LMS lathes, which are quite nice in my view, would make me seriously consider them without a two-speed gearbox.
--
Regards,
Charlie
New Jersey, USA
--
Clausing 8520, Craftsman 12x36 Lathe, 4x12 mini lathe, 14" Delta drill press, 40 watt laser, Consew brushless DC motors and a non working 3D printer
|
Hi, Ralph,
I realize that there would have to be gear reduction to at least a 2500 RPM spindle speed (assuming the desire to duplicate the original mini-lathe speed), but what I was speculating about was whether a Brushless DC motor, geared to 2500 RPM, would produce the same torque as a brushed DC motor geared to 1250 RPM.? I don't know; I have no experience with BLDC motors in lathes.? But the fact it they are used in the LMS lathes, which are quite nice in my view, would make me seriously consider them without a two-speed gearbox.
--
Regards,
Charlie
New Jersey, USA
|
Thanks Charlie, that is what I was thinking, that you had just not removed them.
I would be in the Brushless DC motor camp. But there still would be gear reduction, certainly do not need 4,000?+ rpm.
Ralph
On Mon, Aug 12, 2019 at 4:17 PM Fast Eddie < epinnell@...> wrote: Hi Charlie!
First off, let me be clear that this is not my work, but the work of a very talented man, Robert Fumanarek (sp?) (). John and Robert go back a ways, from what I gather...two gifted and creative people!
With that disclaimer out of the way, yes, the existing screws are removed when mounting the plate and (possibly) replaced by socket head cap screws that are 5mm longer. The motor is also rotated and shifted rearward via a motor adapter to retain the? Sieg OEM motor mounting method. As I understand it, the engineering goal was to minimize alterations to the mini lathe...an easier (if less elegant) GR implementation, to my way of thinking, is Ralph Patterson's jackshaft design ()...but I agree, a GR is very nearly a must-have on these small lathes.
--Ed
--
Clausing 8520, Craftsman 12x36 Lathe, 4x12 mini lathe, 14" Delta drill press, 40 watt laser, Consew brushless DC motors and a non working 3D printer
|
Re: Thank you very much for joining this forum.
Thanks John, one big advantage of this new forum is recording of for me very interesting timely and possible costly/moneysaving projects.
Ralph
As I am only part of the team of hobbyists that have formed this group, we already have some
very respectful members that I have had the pleasure to have known for many years.?
Just looking at the current members list it contains some brilliant practical machinists,including electronics experts.3D printer CNC, ELS and so on.
and if any questions are asked in reference to the "digital age"? of updating our hobby machines,? I am confident you will get ontime dependable
answers and solutions from practical hands on members.
If any major issues occur of which I do not foresee, please do not hesitate to contact me directly, I have
sufficient confidence that we as a group can sort problems out, I am not the best of being PC, and if you feel I need to be?
corrected and brought into line then tell me please.
We are a large family, possibly envious of some families as we share the same goals and interests.
Currently all new members are not moderated, but possibly it maybe necessary to send some "hello" post as a hand shake.
so as you will be able to enjoy and view all posts.
The team are still finding our way around the groups .io .but so far very impressed.
Always seemed the "yahoo groups" that we were a pain for them in the latter years, but original concept was good, and basically a one off.
The object of this forum per month will be a different main "digital age" topic, there?s such a vast spectrum of goodies to chose from, but this does not
mean other our hobby subjects from members, questions and answers will not be dealt with in a timely manner.
It?s a new age, new day, so forward and onward.
Thanks
?
--
John
--
Clausing 8520, Craftsman 12x36 Lathe, 4x12 mini lathe, 14" Delta drill press, 40 watt laser, Consew brushless DC motors and a non working 3D printer
|
Hi Charlie!
First off, let me be clear that this is not my work, but the work of a very talented man, Robert Fumanarek (sp?) (). John and Robert go back a ways, from what I gather...two gifted and creative people!
With that disclaimer out of the way, yes, the existing screws are removed when mounting the plate and (possibly) replaced by socket head cap screws that are 5mm longer. The motor is also rotated and shifted rearward via a motor adapter to retain the? Sieg OEM motor mounting method. As I understand it, the engineering goal was to minimize alterations to the mini lathe...an easier (if less elegant) GR implementation, to my way of thinking, is Ralph Patterson's jackshaft design ()...but I agree, a GR is very nearly a must-have on these small lathes.
--Ed
|
Thanks John, got them on my list!
Hi Ralph. Reference telescoping mini lathe feed/lead screw covers : Visit? LMS?site ref part #?s 5201 and 5202. You will not need the new saddle as supplied by Amadeal in the kit as required for the Real Bull lathes.
Regards
John
Thanks Charlie, that great, right now both of my lathes are just sitting, I probably will not touch them until December so it is? not worth the investment at this time.
The email link came through on the first post for me. ?info@...?? ?went to their website?, they have a lot of stuff but I could not find the "CJ18 Leadscrew Cover Kit".
Ralph
On Sat, Aug 10, 2019 at 11:04 PM CLevinski < clevinski@...> wrote: Oh... it looks like the email address was removed by the .io system, I suppose for security reasons.? I will spell it out here... replace "at" with the ampersand to actually use the address.
info at
--
Regards,
Charlie
New Jersey, USA
--
Clausing 8520, Craftsman 12x36 Lathe, 4x12 mini lathe, 14" Delta drill press, 40 watt laser, Consew brushless DC motors and a non working 3D printer
--
John
--
Clausing 8520, Craftsman 12x36 Lathe, 4x12 mini lathe, 14" Delta drill press, 40 watt laser, Consew brushless DC motors and a non working 3D printer
|
Hi Charlie, My source of material is the local Scrap Yard so that
affects costs a bit (downward)<G>.
Richard
toggle quoted message
Show quoted text
On 12/08/2019 13:49, CLevinski wrote: Hi, Richard,
You have actually completed yours so your figures are likely to be
more accurate that mine.? Your prices in pounds Sterling would be
around US $180-$240, which is appreciably less than my estimate. I did
have to buy a number of aluminum plates for motor mounts and the such
that I did not have, which increased my cost a bit.
Thanks for providing additional clarification on the costing!
--
Regards,
Charlie
New Jersey, USA
|
Hi, Richard,
You have actually completed yours so your figures are likely to be more accurate that mine.? Your prices in pounds Sterling would be around US $180-$240, which is appreciably less than my estimate.? I did have to buy a number of aluminum plates for motor mounts and the such that I did not have, which increased my cost a bit.
Thanks for providing additional clarification on the costing!
--
Regards,
Charlie
New Jersey, USA
|
The subject of the cost of the ELS system came up before I joined and
was indicated at $400 - $800.
Just for interest my feeling is that the cost in the UK is more like
?150 - ?200.
This is based on making everything that you can make and buying the rest
of the items at the best price.
Typically the Mega 2560 can be bought at ?35 in the UK but if you are
prepared to wait it is ?7 from China.
The same goes for the Joystick, Buttons, display, encoder.
Drives and motors are sometimes better purchased locally. Enclosures can
be made.
Richard
|
Hi, Fast Eddie,
Many thanks for the explanations and the photos.? I have personally never seen the end bell of the Sieg motor, and this clarifies a number of things for me.
If I interpret the mounting plate photo correctly, it it mounts by sharing the screws that hold the end bell onto motor?
That is a nice, compact gear reduction unit!
Re brushless DC motors (BLDC), they definitely have many advantages, especially (for our lathes) the fact that torque is flat throughout the rated operating range.? This eliminates the significant loss of torque at? low speeds that we get with brushed motors.? But I don't know whether that torque improvement is great enough to equal the doubling (approximately) of torque that occurs when adding a 1:2 gear reduction.? I agree with you that, if I designed a new mini-lathe today (well... way beyond my mechanical abilities!), I would absolutely incorporate a BLDC, even if I kept the two-speed gearbox, just for the flat torque curve.
--
Regards,
Charlie
New Jersey, USA
|
Thank you very much for joining this forum.
As I am only part of the team of hobbyists that have formed this group, we already have some
very respectful members that I have had the pleasure to have known for many years.?
Just looking at the current members list it contains some brilliant practical machinists,including electronics experts.3D printer CNC, ELS and so on.
and if any questions are asked in reference to the "digital age"? of updating our hobby machines,? I am confident you will get ontime dependable
answers and solutions from practical hands on members.
If any major issues occur of which I do not foresee, please do not hesitate to contact me directly, I have
sufficient confidence that we as a group can sort problems out, I am not the best of being PC, and if you feel I need to be?
corrected and brought into line then tell me please.
We are a large family, possibly envious of some families as we share the same goals and interests.
Currently all new members are not moderated, but possibly it maybe necessary to send some "hello" post as a hand shake.
so as you will be able to enjoy and view all posts.
The team are still finding our way around the groups .io .but so far very impressed.
Always seemed the "yahoo groups" that we were a pain for them in the latter years, but original concept was good, and basically a one off.
The object of this forum per month will be a different main "digital age" topic, there?s such a vast spectrum of goodies to chose from, but this does not
mean other our hobby subjects from members, questions and answers will not be dealt with in a timely manner.
It?s a new age, new day, so forward and onward.
Thanks
?
--
John
|
I think one of the problems with the Sieg motors is that the end bell is radiused, not flat. I believe the end bell is some sort of filled nylon.  A similarly designed plate that attaches to the end bell of a Sieg would look like this:  And a similarly designed, completed GR for the Sieg does away with the idler and is more compact...  ?(design and all photos by Robert F.) But I think possibly a more modern way of doing things is to use a BLDC motor ala LMS HiTorque machines, but I may be wrong.
|
Hi Ralph. Reference telescoping mini lathe feed/lead screw covers : Visit? LMS?site ref part #?s 5201 and 5202. You will not need the new saddle as supplied by Amadeal in the kit as required for the Real Bull lathes.
Regards
John
Thanks Charlie, that great, right now both of my lathes are just sitting, I probably will not touch them until December so it is? not worth the investment at this time.
The email link came through on the first post for me. ?info@...?? ?went to their website?, they have a lot of stuff but I could not find the "CJ18 Leadscrew Cover Kit".
Ralph
On Sat, Aug 10, 2019 at 11:04 PM CLevinski < clevinski@...> wrote: Oh... it looks like the email address was removed by the .io system, I suppose for security reasons.? I will spell it out here... replace "at" with the ampersand to actually use the address.
info at
--
Regards,
Charlie
New Jersey, USA
--
Clausing 8520, Craftsman 12x36 Lathe, 4x12 mini lathe, 14" Delta drill press, 40 watt laser, Consew brushless DC motors and a non working 3D printer
--
John
|
Hi, Ralph, The Gear Reduction unit itself includes just three gears; the pinion, an idler gear, and the gear/pulley that drives the belt.? The two larger gears shown in the photo were part of the threading setup that I didn't bother to remove for the photo.? Perhaps the photo below, taken a year or two after the GR unit was first installed, shows it more accurately. Incidentally, since the mini-lathe can be electrically reversed, you would think that you could do away with the need for the idler gear, whose only function is to make sure that the belt drives in the right directly when the lathe is electrically set to "Forward".? With no idler, you could theoretically just reverse the labeling on the electrical "Forward/Reverse" switch and save the extra gear.? BUT... Real Bull lathes put a resistor in the circuit to reduce the lathe speed when running in reverse.? I don't know if that is true of Siegs, but it is with the Real Bull.? So the idler is necessary. Also, you will notice the curved slots in the GR unit at the front of the motor.? These are for cooling, but are also used for setting the position of the GR unit before tightening the radial set screws.? You can see the three small screws going through the slots.? It is necessary to remove the front end cap from the motor and tap it for some small screws; I used 6-32, but M4 would also work fine.? As I understand it, Sieg lathes use a motor with a plastic front end cap, which cannot be reliably tapped, while the Real Bull end caps are metal.? For that reason, this gear reduction unit will work on Real Bull lathes, but not Siegs.? No matter, as there are numerous other gear reduction designs out there that work fine on the Sieg.? The point is to get the torque up there... this comes at the expense of top speed, but I have never been very comfortable spinning my 4-inch chuck at 2500 RPM anyway!  -- Regards, Charlie New Jersey, USA
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Charlie, what are the gears in front for? It looks rather complicated.
Ralph
Hello, All,
While it's not absolutely necessary, I feel that gear reduction on the mini-lathe makes it more like, as my friend Barry once described it, "a big boy lathe".? This is especially true when used with ELS, which can take good advantage of the higher torque.? I implemented one of John Lindo's gear reduction systems, which he was kind enough to build for me, back in 2015.? You can see it in the photos below with the cover and much of the headstock gearing system removed, as well as fully assembled.? This has proven to be very useful, enabling significantly heavier cuts, which translates to fewer repeated cycles for a given operation.? Just a thought regarding modifications that can make a real performance difference in the mini-lathe...
--
Regards,
Charlie
New Jersey, USA
--
Clausing 8520, Craftsman 12x36 Lathe, 4x12 mini lathe, 14" Delta drill press, 40 watt laser, Consew brushless DC motors and a non working 3D printer
|
Hello, All, While it's not absolutely necessary, I feel that gear reduction on the mini-lathe makes it more like, as my friend Barry once described it, "a big boy lathe".? This is especially true when used with ELS, which can take good advantage of the higher torque.? I implemented one of John Lindo's gear reduction systems, which he was kind enough to build for me, back in 2015.? You can see it in the photos below with the cover and much of the headstock gearing system removed, as well as fully assembled.? This has proven to be very useful, enabling significantly heavier cuts, which translates to fewer repeated cycles for a given operation.? Just a thought regarding modifications that can make a real performance difference in the mini-lathe...   -- Regards, Charlie New Jersey, USA
|
Hi, Ralph,
I would suggest that you email them when you are ready.? I recall that I couldn't find it, either, and had to email them for info.
--
Regards,
Charlie
New Jersey, USA
|
Thanks Charlie, that great, right now both of my lathes are just sitting, I probably will not touch them until December so it is? not worth the investment at this time.
The email link came through on the first post for me. ?info@...?? ?went to their website?, they have a lot of stuff but I could not find the "CJ18 Leadscrew Cover Kit".
Ralph
On Sat, Aug 10, 2019 at 11:04 PM CLevinski < clevinski@...> wrote: Oh... it looks like the email address was removed by the .io system, I suppose for security reasons.? I will spell it out here... replace "at" with the ampersand to actually use the address.
info at
--
Regards,
Charlie
New Jersey, USA
--
Clausing 8520, Craftsman 12x36 Lathe, 4x12 mini lathe, 14" Delta drill press, 40 watt laser, Consew brushless DC motors and a non working 3D printer
|
To John on forming the group.
Richard
|
John Lindo