By continuing to use this site, you agree to our use of cookies. Find out more
Forum sponsored by:
Forum sponsored by Allendale Jan 24th

Motor for a Gingery shaper

All Topics | Latest Posts

Search for:  in Thread Title in  
dcosta23/02/2011 19:11:07
486 forum posts
206 photos


Several months ago I started building a shaper (You can see some images not updated since long ago in my album), which is in a test phase of motorization and movements. I want to clarify that although I used information stemmed from the book by David Gingery, I didn't faithfully followed the book. I did not use castings, I “metrified” all the measures, I used a timing belt and pulleys instead of their "bicycle chain", in addition to other changes that will relate to those who might possibly be interested ...

I've been using in the tests a small engine that has served to assess the correctness of the movement but will not be able to produce any cutting as the time comes.
So, I am currently looking for an engine to move the shaper.
The ideal would be an engine having at least 3/4 hp and rotating at about 1000rpm so, the rotations would be reduced by 1:4 ratio between the pulley mounted on the motor shaft and the pulley mounted on the input shaft of the movement in shaper
So far I have had an eye on a motor with a gearbox and waiting for "a good moment" to buy it.
But, the multiple very informative posts on the topic "Mill and lathe motor upgrades”, made me think that the solution for my shaper may lie on a set of inverter + motor keeping a pulley connecting the motor and the shaper in the reduction ratio to be s
tudied. I thought the price of motor + inverter solution would be too expensive for the end in sight.

Does anyone have an opinion on this matter available to share?

Thanks in advance
Dias Costa

Edited By Dias Costa on 23/02/2011 19:13:45

Bryan Rozier23/02/2011 20:24:32
13 forum posts
Hi Dias,
I have a old Atlas 7inch Shaper which the Manufacturer supplied with wither a 1/3HP or 1/2HP motor running at 1740 RPM (no doubt running off 60Hz in the USA).
This Runs a counter shaft and which then has a Pulley with 4 Steps (Giving 4 speeds).
Including the Bull Wheel reduction (Chain drive on the Gingery Shaper) this gives The following Strokes per minute :-
45, 78, 122, 186.
You could equate that to RPM of the Bull wheel so you have some idea of the reduction required.
If you are using a cheap Motor you might want to go a bit higher than what Atlas used but I'd say 1/2Hp would be enough - what power did Dave suggest? I can't see any referenc ein my copy of his book.
Shapers have variable control of the FPS (Feet Per Second) cutting speed by varying the stroke length so I would suggest that Electronic Speed control is very much over the top and not required in your application. Is it possible for you to buy or make a couple of Cone Pulley to give you a range of speeds?
It will be interesting to see how the timing belt stands up to the shock loads of the shaper.
Good Luck


Keith Long23/02/2011 21:30:15
843 forum posts
11 photos

Hi Dias

When you use the lower speeds on a shaper you'll probably be taking a heavier cut as well, so you will still need all the power of the motor but at the lower speed / higher torque. You will get this with a set of differing size pulleys, but I'm not sure you will by running a motor at reduced speed with an inverter. My understanding is that the phase current will stay pretty much the same, so the motor torque will be the same and hence the motor output power will be lower. If that is the case it will limit the cut depth / width at the lower speeds which is not what you want.

If I'm wrong on this will someone else please correct me.


Terryd23/02/2011 21:55:45
1935 forum posts
179 photos
Hi Dias,
I would say that you don't need the speed range offered by an inverter so would be better with a fixed speed motor and a cone of pulleys to give a limited speed range which, combined with the change of stroke should be sufficient for a shaper. The shaper is a pretty basic machine and I think the simpler the better. I would love one by the way and have really missed seeing your pictures of the progress on your machine.
Best regards
dcosta23/02/2011 23:31:56
486 forum posts
206 photos
Hello Bryan!
Hello Keith!
Hello Terry!

Thanks for Your help.

I hope You understand and forgive if I use only one post to respond to the three of You.

I apologize if I had not exposed all the elements I have related to the shaper in my previous post.

Now I see some more information is relevant for those of You who volunteered to respond to my call to better understand the problem.

1 - I have restrictions in what concernes the weight of the shaper and now I already have trouble moving it.
2 – I have restrictions in what concernes space constraints. For this reason I rejected the mechanic train as proposed in the book (Gingery's book) and therefore considered the possibility of a motor plus reducer which would build a shaper with a small footprint all of it mounted on an aluminum base plate and relatively movable. I must say I intend to install the shaper on a bench in steel plate similar to the bench on which my Optimun BF20 milling machine is mounted on a wheeled dolly.
3 - As you can see in the book (and also in my album), the structure of the shaper is practically all of it made of aluminum.
The collection of Gingery's books is almost a full proposal of machines made of aluminum with a machine being used to make the next machine and so on. This makes me be a little suspicious about the ability of this machine to cut steel. I've seen on Youtube one or two shapers working but every time cutting aluminum or some plastic.

Although I would like my shaper to be a little stronger...
4 - I have a band saw that is driven by a small motor 1/2HP with a small gearbox between the motor and the wheel that moves the cutting band .
Once it works beautifully, with a use that is not lower than the expected use for the shaper I thought that a similar solution could be implemented, even taking into account that while the effort of the band saw is contínuous (almost. ..) the shaper will find some strong bumps.
5 - The solution of using inverter plus motor has the charm of generate an acquisition that could temporarily fill another role (eg.: be used in the lathe if its motor breaks down, etc.).

That's all ocurring to me by now


I have my workshop with pieces all over the place waiting for the bench to put the shaper on it and gain some space over and inside it. When I'll have the bench and the workshop in order, I'll make some pictures and a small film to show the “state of the works”.

Thanks for Your help

Dias Costa

Edited By Dias Costa on 23/02/2011 23:42:09

John Olsen24/02/2011 09:11:29
1079 forum posts
91 photos
1 articles
Well, as the owner of four shapers, I would agree with Bryan above that 1/3 to 1/2 hp should be enough for a shaper the size of the Gingery one. You will be able to cut steel or cast iron OK, bear in mind that most machines are made of cast iron which is not a lot different in strength to aluminium if I remember correctly. The main downside to the aluminium will be that it can be scratched and worn more easily, but for home use with care it will be OK.
You don't really need a lot of variation in speed for a shaper, none of mine have more than four speeds provided and the smallest one, 6-7 inches stroke has only three speeds. While it is true that you can adjust the speed by changing the stroke, you have to have the stroke long enough to cover the whole length of the job with a bit to spare. Making it longer will increase the cutting speed, but since the tool will be cutting less of the time, there is no net gain. A shaper will usually give a lovely finish, even at low speeds on alloy, so there is no great need to vary the speed a lot. I would agree however that you really want the torque when you reduce the speed, and this tends to mean that you want to change the ratio, not just reduce the speed.
To expand on the above, a motor with a speed controller will be able to produce about the same torque at any speed within its range. So at a quarter of full speed you will get about the same torque as at full speed. If you reduce the speed with pullies or gears, you will get four times the torque when you reduce the speed to a quarter. So for instance although my Myford has a speed controller on it, when I am turning a 6 inch blank for a flywheel, I still engage backgear and drop the speed on the belt as well. That lets me take a heavy cut at a reasonable cutting speed. If I just reduced speed on the controller, I could take a cut at a suitable speed, but not a very heavy one. (Heavy is relative, the Myford does not take what the blokes in industry would call a heavy cut!)
A shaper is not a machine that you would use if you were in a great hurry anyway, which is why they have largely vanished from industry. For the amateur, their charm is the low cost of tooling, and the fact that they are a charming and relaxing machine to watch.
So for the Gingery, I would suggest that you probably do want to stick with a belt drive with stepped pullies or some equivalant. The final reduction, which on commercial shapers is usually a pair of gears, probably want to be a positive drive, eg at the minimum a toothed belt. One of my shapers has a synthetic resin bonded fibre gear for the bull wheel, which suggests to me that a toothed belt drive would stand up to the service OK. A shaper used properly does not impose enormous impact loads on the parts, although it can when accidents happen. In such a case the belt would be good, since it would jump a tooth , or at worst strip the belt, which is cheaper than a gear. I think the SRBF gear in mine may have been intended as a "weakest link", although an old repair to the slotted arm shows that this did not work out. Now that spare gears are no longer available, it becomes a bit of a worry, although I am sure I could make one if I had to.
Can you mount the motor under the machine, below the top of the bench? It would mean the shaper would become part of the bench, but might help you to keep the bench space small.
dcosta27/05/2011 18:57:33
486 forum posts
206 photos
Hello Bryan!
Hello Keith!

My old JVC camera just arrived.

I made a small bad film (I even fell when making it) of it.

I can send the film file in one of the following formats: VOB (best quality), MP4, MOV, WMV and FLV (worst quality). The longest (VOB) has around 350MB and the shortest (FLV) has around 32MB.

If You are interested please send personal mail to me ( with an adequate e-mail address.

Best regards
Dias Costa

dcosta04/06/2011 19:49:33
486 forum posts
206 photos
Hello Bryan!
Hello Keith!
Hello Terry!

This afternoon I put a small video of the present situation of the works in my Gingery's shaper.
As I wrote before it was made from aluminum plate instead of cast aluminum.
It uses a timing belt and pulleys instead of a sprocket and chain.
I still need to build the work table on top of the angle plate shown in the video. Then I will mount the machine on an appropriate bench.
The motor will be replaced with a 1/2HP or a 3/4Hp.
With the new motor in place, I will test the machine: first cutting plastic, then some soft metal like aluminum, and finally try to cut steel.

If You are interested You can see it at
Thanks for the interest
Dias Costa

Edited By Dias Costa on 04/06/2011 20:06:35

dcosta22/12/2013 16:45:36
486 forum posts
206 photos

Hello all, good afternoon.

Soon, after cleaning it and removing rust resulting from the fire, I'll re-start building the Gingery shaper machine and, again, find myself in the position to search a motor for it. Turns out, here in Portugal, I only find too expensive and too heavy motors, therefore, in preparing a request to ArcEuroTrade I discovered that they have a stepper motor with 650Ncm that with a small driver which delivers 6.5A, could be used to move the shaper machine.

Information on the stepper motor can be found **here**:
Information about the driver can be found **here**: I already use this drive to automaticaly feed the X axis of my milling.

I don't know how to compare or convert Ncm to Watts or HP.
Will 650Ncm
be enough?
Will I get enough rpm?
Do you think this is a workable idea?

I would like to know your opinion, please...

Best regards
Dias Costa

Michael Gilligan22/12/2013 17:20:56
16202 forum posts
706 photos


I see nothing wrong with the general concept ... You may even persuade the Stepper Motor to do something extra-useful on a Shaper.

  • For conversion to Power units, have a look here

Magtrol makes Dynamometers, so their calculator should be good!

As for the power requirements; that will depend upon the machine, and what you want it to do.


Michael Gilligan22/12/2013 18:19:00
16202 forum posts
706 photos
Posted by Michael Gilligan on 22/12/2013 17:20:56:
  • For conversion to Power units, have a look here


At the risk of stating the obvious ...

You need to input the Motor's working Speed, as well as the Torque.

... it looks like the chosen motor might be useable if you can drive it at at least 3,000 rpm.


Edited By Michael Gilligan on 22/12/2013 18:20:20

dcosta22/12/2013 19:25:23
486 forum posts
206 photos

Hello MichaelG. Good evening.

Thanks for your help.
If you want to know where I want to use the stepper motor you can see **here** and **here**

Given the formula that you mentioned, would suffice me a 700rpm in the stepper motor for the approximately 400rpm I need in the input of shaper machine.
But I found **here** a calculator that tells me that the values ​​specified for that stepper motor, I will not get more than 60rpm.
Apparently, if I used the calculator correctly, the "dream" ends here and I need to continue looking for a motor.

It remains for me to thank you for the help.

Hope you have a merry Christmas and a happy new year.
Dias Costa

Edited: for correcting the calculator link


Edited By dcosta on 22/12/2013 19:47:54

Michael Gilligan22/12/2013 19:39:45
16202 forum posts
706 photos

Hello Dias,

Thank you for the good wishes ... The same to you and yours.

Could you please insert the link for the calculator that you found ... I would be very interested.

If the chosen motor can only run to 60rpm, then yes; it looks like you need a "normal" motor.

Why, I wonder, are they so expensive in Portugal ???


dcosta22/12/2013 20:13:39
486 forum posts
206 photos

Hello MichaelG .

Thank you for your help and interest.

For the general public, in Portugal, one electric motor of Chinese manufacturing, 3/4HP, costs about 100,00€ (VAT included ) and it's biger than I like and heavy. I think the explanation for the high price resides in the fact that there is little demand.
The last electric motor I bought, 4 years ago, is 1/2HP, was part of a hydraulic pump and it cost me more than 100,00€ . It is small and light and warms up a bit after several minutes working . It is the motor that I use in my Harold Hall 's Tool and Cutter Grinder that you can see some pictures of **here** and **here**.

The temptation by the stepper motor has to do with its price, its dimensions, the possibility of some rpm control and the fact it works with low voltage .

Strangely, at least for me, the low voltage and high torque motors similar to those used in some milling and turning machines with continuously variable speed are not commercially available. I for one, have not been able to find them. One such motor would be a good alternative for the shaper machine .

My best wishes
Dias Costa

Versaboss22/12/2013 23:07:58
455 forum posts
51 photos

Hello Dias,

why not Ebay?

I was looking around a bit and under AC motors I found this as first entry:

You are lucky, they would send it to your country, but not to mine! angry Ebay devil

Greetings, Hansrudolf

Ian S C23/12/2013 11:36:21
7468 forum posts
230 photos

Dias, to get a lower speed, you could go to an 8 pole motor, 720rpm, or a 6 pole motor with 960 rpm, but these maybe hard to find, and expensive, the other way is a geared motor, probably a 4 pole type, 1450rpm, this would be more compact than a jack shaft and belts and pulleys. I think 1/2 hp would be enough for your machine.

Ian S C

dcosta26/12/2013 00:04:25
486 forum posts
206 photos

Hello Hansrudolf.

H: why not Ebay?
DC: I don't like Ebay. Tried once and promised never more buy through them.

H: I was looking around a bit and under AC motors I found this as first entry:
You are lucky, they would send it to your country, but not to mine! angry Ebay
DC: It's a very nice motor and it could fit nicely the shaper. But after reading "Restricted categories" under "Buying an item through Global Shiping Program" I see that only perhaps I can buy a motor from them in the desired conditions (price including transportation and import charges).

Anyway, I thank you very much for your help.

I wish you have a prosperous new year
Dias Costa

dcosta26/12/2013 00:16:00
486 forum posts
206 photos

Hello Ian, good morning.

I: Dias, to get a lower speed, you could go to an 8 pole motor, 720rpm, or a 6 pole motor with 960 rpm, but these maybe hard to find, and expensive, the other way is a geared motor, probably a 4 pole type, 1450rpm, this would be more compact than a jack shaft and belts and pulleys. I think 1/2 hp would be enough for your machine.
DC: You're right about the motor power. I have thought about power 1/2HP or 3/4HP depending on the weight, size and price.
I've not yet built the structure that will underpin shaper and also the motor. So I'm not sure that a heavy electric motor will not contribute to unbalancing the set.

Please see my next post...

I wish you have a prosperous new year
Dias Costa

dcosta26/12/2013 01:40:39
486 forum posts
206 photos

Hello Michael, good morning.

MW: (1) Washing machine motor . Cheap and available anywhere from service agents. Rugged, high torque and variable speed if you want it .
Need to make or adapt a controller of some sort for variable speed but there are standard designs for doing that .
Personally I would run motor at moderate quasi fixed speed and do all drives and speed changes with belts and pulleys .
DC: As a result of the fire in my garage / workshop, one vertical load washing machine broke down and I dismantled them but kept the motor. When I packed several objects, including the motor, did it so well that I never more remembered it ... Now you made me remember I have it. Thank you!

MW: (2) Ordinary stepper motors are not ideally suited to simple higher speed high torque drives . Can be done but not worth the effort and cost .
DC: Yes I think you are right. But, here in Portugal we have an aphorism that says that if you do not have a dog to hunt, you may hunt with a cat...
See my reasons in a previous post.

MW: (3)(Any) motor for a machine tool drive needs to have good speed regulation.
This means that motor must maintain a set speed intrinsically with quite large variations of drive load .
Two cases apply:
Over a succession of armature revs.
Within one motor rev.
This regulation can be optimised by motor design or sometimes can be artificially achieved with electronics .
DC: The only source of information for the purpose of building the shaper I have followed is the dave Gingery book. That's why I already made a three step pulley
to receive 1800rpm from the motor, directly or through kind of reduction.

MW: Three phase motors have intrinsically better regulation than single phase ones and this is why they are so good for machine drives.
DC: See a previous post for my reasons and dificulties. Structure, price, weight and size.

MW: (4) What actually happens at the cutting end of a machine tool drive also depends on the nature of the intermediate drive .
Lots to consider but one feature relevant to shapers is certainly flywheel effect of pulleys and gears .
DC: Yes I think you are right. See, please, answer to your point (3).

MW: Lots more to talk about if you want.
DC: I would appreciate that. Thank you.

I wish you have a prosperous new year
Dias Costa

Versaboss26/12/2013 10:31:33
455 forum posts
51 photos
Posted by dcosta on 26/12/2013 00:04:25:

DC: I don't like Ebay. Tried once and promised never more buy through them.

DC: It's a very nice motor and it could fit nicely the shaper. But after reading "Restricted categories" under "Buying an item through Global Shiping Program" I see that only perhaps I can buy a motor from them in the desired conditions (price including transportation and import charges).

Hello Dias,

well if you have an issue with Ebay then that's your decision. But what intrigues me a bit is the remark about the Global Shipping Program. As far as I read the offer, this seller is shipping directly; I can't see a mentioning of G.P.S. The latter is a system where the seller sends his Item to a Ebay distribution center (in the U.S.) and they do (at a price I think) the final packaging and shipping. Ebay then also issues the final invoice to the buyer. Quite a complicated system; I hit on an article some days ago which I couldn't buy that way because Ebay didn't accept my address.

Greetings, and all the best in 2014


All Topics | Latest Posts

Please login to post a reply.

Magazine Locator

Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!

Find Model Engineer & Model Engineers' Workshop

Latest Forum Posts
Support Our Partners
Eccentric July 5 2018
Eccentric Engineering
Subscription Offer

Latest "For Sale" Ads
Latest "Wanted" Ads
Get In Touch!

Do you want to contact the Model Engineer and Model Engineers' Workshop team?

You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.

Click THIS LINK for full contact details.

For subscription issues please see THIS LINK.

Digital Back Issues

Social Media online

'Like' us on Facebook
Follow us on Facebook

Follow us on Twitter
 Twitter Logo

Pin us on Pinterest