# Sherline Gear-Driven Power Feed



## premodern (Sep 11, 2018)

I posted this on the Yahoo Sherline forum but thought that Sherline owners here might find it of interest.  This is a video of an older Australian Sherline that was for sale in Europe. Notice the unique gear driven power feed system. It looks like the designer was inspired by the Sherline threading system and took it a step further.









By the way....I was looking on the Sherline website for their motorized power feed system (P/N 3001) and while I could find replacement parts, I could not find the entire power feed system as such. Did they cease offering it?

~Hans


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## dlane (Sep 11, 2018)

i never had any luck with the sherline threading gears ,I think there powerfeed motor is a BBQ rotisserie motor.


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## mikey (Sep 11, 2018)

Pretty cool set up in the video.

The Sherline power feed was just a single speed, non-reversible rotisserie motor that was way overpriced. It came  with an adapter to fit the motor to the end of the lead screw and it ran really hot. In my opinion, it was a POS. 

A much better option is to hook up a reversible DC variable speed gear motor to the lead screw; direct drive via an adapter between the output shaft of the motor to the end of the lead screw works fine. This gives you variable speed and feed to precisely dial in a cut on the fly and it works extremely well. Gearing is fine but why bother tying the feed to the speed for turning? A VS motor is far, far better and is easily disconnected for threading.


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## premodern (Sep 11, 2018)

Good points, Mikey.

In addition, it would eliminate any gear noise being transmitted to the spindle. 

One would think that the folks at Sherline could put together a nicely designed package along those lines.

~Hans


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## mikey (Sep 11, 2018)

I suspect most users don't realize what a boon a variable feed is because they never used it before. The typical lathe gearbox ties speed and feed together, even for the guys with variable speed motors. Having variable feed independent of variable speed allows you to dial in a cut for almost any material and this is one reason I use the Sherline lathe for most smaller parts that will fit in that lathe - it works better than my bigger lathe. The lathe itself is already very accurate but the VS speed/feed thing produces fine finishes that you can't get on a standard lathe.

Sherline can put a good package together but it would cost the buyer. If you can't sell it then why bother? The guys that really use it already have a CNC Sherline lathe.


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## Forty Niner (Sep 12, 2018)

mikey said:


> Pretty cool set up in the video.
> 
> The Sherline power feed was just a single speed, non-reversible rotisserie motor that was way overpriced. It came  with an adapter to fit the motor to the end of the lead screw and it ran really hot. In my opinion, it was a POS.
> 
> A much better option is to hook up a reversible DC variable speed gear motor to the lead screw; direct drive via an adapter between the output shaft of the motor to the end of the lead screw works fine. This gives you variable speed and feed to precisely dial in a cut on the fly and it works extremely well. Gearing is fine but why bother tying the feed to the speed for turning? A VS motor is far, far better and is easily disconnected for threading.



Mikey, I have the Sherline power feed on my lathe and would like improve upon it.  So, do you have a recommendation for the reversible DC variable speed gear motor you mention?


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## mikey (Sep 12, 2018)

Hang on, Sir. I have to finish cleaning the house first; my wife said so. I'll dig out my motor as soon as I can and tell you what I'm using.


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## mikey (Sep 12, 2018)

Forty Niner, I have a Leeson DC gear motor, model # 985.613. It is just a 1/8HP motor geared to run at 94 rpm max. The thing is 11# in weight and is double the size of the Sherline main motor so its pretty huge. I use a Dayton 5X412A controller with it and it is reversible. I bolt the motor to the mounting board that holds my lathe so it is stable. I connect to the Sherline leadscrew via the typical Sherline adapter that is then connected to a Lovejoy flexible coupling. The other half of the flex coupling is connected to the motor's output shaft. Takes a few minutes to set up. The controller is mounted to a bracket close to the motor and I can reach both the feed and speed pots easily.

This thing is really, really useful. I hate cranking on longer work pieces so I can take a cut and then reverse it to move back to the end of the work piece to take another cut. I use this arrangement for longer work pieces or when the finish needs to be really fussy. I also use it when cutting stainless to keep my feeds steady.

As I said, having the feed independent of speed is the best way to use a lathe, at least in my opinion. This works like a charm.


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## Forty Niner (Sep 12, 2018)

Thanks for that information. I'll keep my eye out for something like that.


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## premodern (Sep 13, 2018)

Thanks for the information, Mike. Very helpful.

~Hans


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## ttabbal (Sep 13, 2018)

I like the idea of an independant, adjustable drive for the power feed. I might have to try it on my PM1127. The only motor I have free right now is a treadmill motor with a 10,000 RPM rating. A bit much.  I'm thinking either a nice VS DC gear motor or a mid size stepper. Have a few things to work on before I mess with it though.


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## mikey (Sep 13, 2018)

The 1127 has a drive shaft that is tied to the gear train via a spur gear on the end of the shaft. You would need to remove the gear and make an adapter for the DC motor but it could be done. I've looked at mine so I know its possible but you have to find a way to support the gear motor. If you ever get to Oahu, come by and I'll show you how well this speed/feed thing works.


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## mikey (Sep 13, 2018)

I wanted to show you what the feed motor does but I don't have many pics of something like that. I do, however, have a pic of my live center and I used the feed motor to machine the thing. The bearing housing and tailstock arbor are 1144 Stressproof steel and the tips are O-1 tool steel, hardened and tempered. The components you see are as they come off the lathe - no polishing, sanding or anything. The only process used aside from turning is employing a graver to soften all the edges.




Everything you see here was made on the Sherline lathe with HSS tooling and most of it employed the dc feed motor. Most harder steels, like 1144 and O-1 in particular, like to be finished at high speeds but looow feeds if you want a good finish. It is difficult, at least for me, to get a consistent finish manually. So, for harder materials you want to use low speeds with moderate feeds to rough and high speeds with fine cuts at low feeds to finish and a power feed will aid in both instances. 

Imagine if your speeds and feeds were tied together via a gear train; how do you run at high speeds and low feeds if you don't have the gearing to do it? My Emco Super 11 can get close to this (I have a quick change gear box and a full change gear set) but it won't produce the finish you see here, not even on its best day. Most "machinists" consider the Sherline lathe a toy but in my view, they are naive.

It is my opinion that a Sherline lathe needs a small handful of mods to be really useful - a good live center, a rear mounted parting tool, variable power feed and really good HSS turning tools. A graver and a good knurler are icing on the cake.


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## ttabbal (Sep 13, 2018)

Those look great Mike! 

I think most real machinists would think your Super 11 or my 1127 are toys too, but they can do nice work. Same with the Sherline. If the projects I want to do would fit on one, I would have thought about going that way. 

The gear on the end is easy to remove, leaving a keyed shaft. So I suspect I could make a little adapter without too much hassle. Mounting the motor would be a bit more work.


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## mikey (Sep 13, 2018)

Thanks, Trav. 

If you do hook up a feed motor to yours, do a thread on it and show what it can do. I bet there are a lot of guys out there who would find it interesting.


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## premodern (Sep 14, 2018)

mikey said:


> I wanted to show you what the feed motor does but I don't have many pics of something like that. I do, however, have a pic of my live center and I used the feed motor to machine the thing. The bearing housing and tailstock arbor are 1144 Stressproof steel and the tips are O-1 tool steel, hardened and tempered. The components you see are as they come off the lathe - no polishing, sanding or anything. The only process used aside from turning is employing a graver to soften all the edges.
> 
> View attachment 275431
> 
> ...


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## premodern (Sep 14, 2018)

Impressive, Mike.  I also remember your rear-mounted parting tool post which was very helpful. An Emco and a Sherline....the best of both worlds!


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## blu73 (Sep 20, 2018)

I am currently working on a power feed that I hope will do exactly what some of you have mentioned.  It will be independent from the spindle, has variable speed, and is reversible.  The advertised output speed of the gear motor I selected is supposed to be 300 rpm, which is about 15 times the speed of the 3001 I just sold.  I don't know yet if I am wasting my time and money on this project, but if things work out as I hope, I will post information here detailing what I did to come up with a much more versatile alternative to the Sherline offering.  On second thought, I suppose I should also post something if it is a failure, so others won't waste time and money trying the same thing.
By the way, I contacted Sherline about the 3001 and they replied that it is at least temporarily discontinued due to the supplier no longer producing the motors.

Russ


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## mikey (Sep 20, 2018)

Let us know how it works out, Russ. I suspect 300 rpm might be a bit fast but you never know. As long as you can maintain torque at low speeds then it should work out.


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## blu73 (Sep 20, 2018)

My main reason for the top speed of 300 rpm was mostly to allow for a more rapid movement of the saddle when I needed to move it long distances.  I don't know how many times I had to move the saddle to get room for a measurement or something and at only .05 travel for every revolution of dial, it got old very quickly.
The 3001 power feed would rotate at about 20 rpm.  That is great for some situations, but not all.  The other restriction, of course, is the single direction of feed.  If I find that the motor I am about to use doesn't have adequate torque for low speed work, there are others of the same size that offer lower speeds of output.  This really is a work in progress and may go through several changes.  I just hope I guessed correctly the first time.  Odds are, I didn't.

Later,
Russ


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## mikey (Sep 20, 2018)

blu73 said:


> My main reason for the top speed of 300 rpm was mostly to allow for a more rapid movement of the saddle when I needed to move it long distances.  I don't know how many times I had to move the saddle to get room for a measurement or something and at only .05 travel for every revolution of dial, it got old very quickly.



Oh, I know exactly what you mean! You are going to absolutely love a reversible VS DC motor, trust me. It is a real treat to be able to adjust speed and feed on the fly. All those guys with VS lathes are still forced to live with feeds tied to their gear ratios - not us!!!


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## blu73 (Oct 20, 2018)

Well, I've messed around with this power feed a little and found that I could easily stall the thing when trying to feed at a slow rate.  I'm going to change out the 300 rpm motor for a 200 like I mentioned earlier.  Meanwhile, here are two pix of what I came up with.  The rotary control has an "off" position with a distinct feel and sound.  The rocker above the dial is to select direction and it has a center off position.  The red switch on the right is for main power.  It is always lit up, so I know power is applied to the unit.  I feel that's a plus, as the visual reminder will help me remember to unplug it when not in use.  No sense taking a chance on burning anything up.  The second pix shows how I got power into the control.  It is a computer style power entry point.  I did this so I wouldn't have to deal with six feet of power cord flopping around if and when I need to open the box.
  Oops, almost forgot.  The motor and external bracket are attached to a 3/16" thick aluminum plate inside the box for support.  The box is made up of .04 aluminum and it would never be able to handle the stress.

Russ


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## prasi79 (Oct 20, 2018)

Nice... )


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## mikey (Oct 20, 2018)

Came out nice, Russ. Has everything you need in a clean package. 

Is the speed of the motor you're using tied to the torque it produces? That is, will the 200 rpm motor produce more torque than the 300 rpm one? You need torque more than speed in this application.


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## blu73 (Oct 20, 2018)

I'm pretty sure it will.  Both motors are advertised to turn at 5000 rpm rotor speed that is then reduced through a gear train.  With everything being equal before the gear train, giving up revs through the gearing to get a slower output should increase torque at the output shaft.

Russ


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## mikey (Oct 20, 2018)

Keep us posted, Russ. When you get it working well, post up the motor info if you will. Other guys might follow your lead. Again, nice work!


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## blu73 (Oct 23, 2018)

Okay, I just purchased a 200 rpm motor this morning.  When it arrives and I swap it in, I'll take some pix of everything and post them along with details of what's in the box and the mods to make everything fit.

Russ


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## Ben Nevis (Oct 28, 2018)

I just ran across this video on youtube.


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## mikey (Oct 29, 2018)

60 rpm little gear motor that should be fast enough for turning. I wonder how many inch pounds of torque it develops because if you take a really healthy cut, say 0.050 - 0.060" deep, in mild steel then I wonder if it can keep up. I can tell you that the original Sherline power feed motor struggled to keep up with the cuts my tools can take, although to be fair it turned at a constant 100 rpm. 

My Leeson power feed motor is bigger than the main Sherline motor, can go up to 100 rpm and has tons of torque. It will drive the carriage no matter how big a cut I take. This might sound trivial but if the motor is struggling then that will show up in the finish so keep that in mind when choosing a motor.


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## blu73 (Nov 7, 2018)

Okay, the 200 rpm motor arrived the other day and everything is back together again.  I made a few unscientific tests and I'm satisfied with the results I got.

*Now, I know this isn't going to be for everyone, but it works for me.*  I tend to take fairly light cuts when turning.  Usually .01 per side, but sometimes .02 depending on the material.  I have seen mention here and on other sites of cuts around .05 deep.  That's just not my style.  I may baby this lathe, but again, that's just me.  If you decide to do something similar, all the components I used were found on line with very little searching.  There are plenty of choices to make, and with some careful shopping, this can all be done for less than $50.

Be sure the lathe is properly adjusted, cleaned and lubricated.  I noticed a change in the pitch of the motor as the saddle moved along the length of the bed.  I found some light corrosion and dust on the bed ways from sitting unused and uncovered for about a month.  Also, be sure your tooling is sharp, secure and set up properly.

So, here we go.  This first picture shows the difference between the two motors.  The large one weighs around twice as much as the smaller one, and a lot of that is due to a larger armature.  It was advertised as "high torque" and compared to the smaller one, this is true.  One simple test I did was to try to stop the motion of the saddle with my finger.  Barely slowed it down.  Making a .01 deep cut in steel didn't strain the drive much at all.  Now it's just going to be a process of finding settings on the speed dial for things I need the drive to do.




This next picture shows the various electrical components in the enclosure.  It took some time through trial and error to come up with something that worked, and this can still be improved upon.  I plan to clean up the coil of black wire, as it takes up too much valuable space in the little 3x4x5" box.  The circuit board on the bottom of the box is the power adapter.  It was removed from the shell it came in and hot glued to a piece of plastic that was hot glued to the bottom of the box.  Mounted vertically at the left end of the power supply, is the speed control.  It came with a pre-wired switch to handle direction changes for the motor.  I know it looks kind of cluttered in there, but sometimes you just need to think differently.  This is what I needed to do to get everything to fit.  The small blue block you see near the bottom center of the picture is a terminal block that made hooking up the 12VDC output from the power adapter very simple.




Here is the shell of the power adapter.  I cut it along the parting line with a hobby saw, and when the two halves came apart, I cut the two main power leads from the back side of the prongs that plug into the wall.  I was amazed at how little was actually inside that shell.  I performed the surgery on the shell when it couldn't be make to fit in the space available in the box.




The last thing I want to show is how to ground the main power coming into the metal box.  The power entry port I used made this very easy, as it has blade type connectors on the back.  All three lugs are marked as to how they should be hooked up.  Line, neutral and ground.  The circuit board from the power adapter was also marked for polarity, as are the connections on the speed control.  As long as you watch for polarity markings on the different components, it should all go pretty smoothly.  The first motor I tried ran in the directions called for when the switch was set for left or right.  The larger motor has a mark that I took to be for the positive lead, but it ran backward compared to the first one.  Test these things before final assembly to save time and effort.  Mark things up so you know where leads go if it is taken apart, and there should be few problems.  At least I didn't have any smoke come out of mine.




And finally, here is the same picture from a previous posting showing the completed control in place.




Okay, I think I've covered everything.  Now I need to find excuses to make some chips.

Russ


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## mikey (Nov 7, 2018)

Great detail, Russ. How does it work?


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## MSD0 (Nov 8, 2018)

mikey said:


> Pretty cool set up in the video.
> 
> The Sherline power feed was just a single speed, non-reversible rotisserie motor that was way overpriced. It came  with an adapter to fit the motor to the end of the lead screw and it ran really hot. In my opinion, it was a POS.
> 
> A much better option is to hook up a reversible DC variable speed gear motor to the lead screw; direct drive via an adapter between the output shaft of the motor to the end of the lead screw works fine. This gives you variable speed and feed to precisely dial in a cut on the fly and it works extremely well. Gearing is fine but why bother tying the feed to the speed for turning? A VS motor is far, far better and is easily disconnected for threading.


I’ve been thinking about doing something like that on my PM1127. The lathe is so much quieter when the change gears are disengaged.


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## mikey (Nov 8, 2018)

MSD0 said:


> I’ve been thinking about doing something like that on my PM1127. The lathe is so much quieter when the change gears are disengaged.



It might be worth a try. Your lathe has a saddle drive shaft that can be hooked up if you pull the drive gear off that shaft and hook up a DC gear motor to it. Speeds and feeds greatly affect the cut, both roughing and finishing, and my experience with being able to adjust both on the fly on my Sherline lathe has convinced me that it is a significant advantage. 

My favorite materials to do this with are 12L14 and 6061 - mirror finishes on both - but it works for almost anything I turn on that lathe. I especially like turning O-1 at high speed for a finish cut but with a very slow feed; the finish is just fantastic under these conditions and you just cannot get that when the feed is tied to the speed through gearing. 

Something to think about ...


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## blu73 (Dec 8, 2018)

I've had a chance to play around with the power feed I built, and for me at least, it looks like a winner.  As I've stated previously, I tend to take cuts of only .010 deep, but to see what the drive could do, I made cuts up to .030 deep in mild steel and the drive didn't seem to hesitate at all.  Not very scientific, but with everything cleaned up, lubricated and adjusted, it worked fine.  The test cuts were made with the 200 rpm motor installed.  I'm thinking about changing that motor out for one that is rated at 100 rpm for better control of feed when turning a diameter.  The down side of that would be giving up how fast the feed unit can get the saddle to move out of the way when I want to get a measurement or something.  At 100 rpm on the lead screw, that's still about five times faster than the Sherline unit I had.  My original reason for building this thing was to get away from having to turn the feed dial by hand when I needed to move long distances.  The ability to independently adjust speed and change direction is great.  It's all about give and take as far as speed and torque are concerned.  I may find that the 100 rpm motor is an even happier compromise.  If the 100 rpm motor works out as I hope, I've got a pretty wild idea brewing that I want to work on next.


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## mikey (Dec 8, 2018)

My motor is just under 100 rpm and it works great. Lots of torque, speed is adequate, control is very good. I suspect you might be happiest with the 100 rpm motor, Russ.


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## blu73 (Dec 9, 2018)

You're probably right Mike.  I got too caught up worrying about speed.  At least I don't have too much money tied up in these things.  The average price of a motor so far is around $15, so it's possible to experiment without spending a lot.  It seems like I spend more time and effort designing and building things *for* the Sherline than anything else.

Russ


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## paul_cpu (Oct 21, 2020)

mikey said:


> Pretty cool set up in the video.
> 
> The Sherline power feed was just a single speed, non-reversible rotisserie motor that was way overpriced. It came  with an adapter to fit the motor to the end of the lead screw and it ran really hot. In my opinion, it was a POS.
> 
> A much better option is to hook up a reversible DC variable speed gear motor to the lead screw; direct drive via an adapter between the output shaft of the motor to the end of the lead screw works fine. This gives you variable speed and feed to precisely dial in a cut on the fly and it works extremely well. Gearing is fine but why bother tying the feed to the speed for turning? A VS motor is far, far better and is easily disconnected for threading.



Interesting you say this as today I bought a electric motor to control the feed instead of a gear set.  I think my Sherline is even older then this ( though it looks the same ).

The motor is a sewing machine motor, currently mine has no speed control but I will build that.


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## Forty Niner (Oct 21, 2020)

The Sherline power feed turns the lead screw at approximately 21 rpm to get the 1" per minute feed listed in the description of the now discontinued device.   I have one and find that the feed works "OK" but I wish for more variability such as that achieved by Mikey with the variable speed gear motor.

The lead screw on my Sherline is 20 threads per inch.  That moves the carriage 0.05 inches per revolution of the hand wheel.  Desirable feed rates would require lead screw RPMs to be adjustable in the 10-60rpm range, IMHO.  The sewing machine type motors that I am familiar with would not produce the required torque in that RPM range, if they even could be made to run that slow.   The speed would have to be "geared down" using a gear box or belt system, I think.


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## paul_cpu (Oct 22, 2020)

Initially I was thinking the electric motor would drive the lead screw for cutting.

Yes I have the sewing machine motor and there is no way I can get that to go slow and produce torque.  The Sherline DC motor is expensive to get shipped to Australia as-well as being in USD, I am thinking I will investigate a brushless DC motor on ebay and make up some pulleys to run that motor.


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## ttabbal (Oct 22, 2020)

If you want to go that slow, a stepper is probably a better option and you will have finer control. If all you want is variable speed, it would be a super simple microcontroller program or even just a 555 timer with a pot to control the speed.


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