Drummond Shaper Feed

[not done it yetParticipant @notdoneityet]

A thread for Drummond Shaper users.

The Drummond hand shaper seems to attract some criticism of its rather coarse feed rate. Clearly, with the 20 tooth ratchet gear mine is fitted with (and an 8 tpi screw thread) the minimum feed rate is 6 1/4 thous. A feed rate of two teeth per stroke would likely be more than enough for a hand operated machine?

Some thoughts were, while making the auto-feed components, how do other people’s systems operate in practice.

Can two, or even three, ratchet teeth feed rate be achieved?

Can these feed rates be adjusted, for any reasonably short ram stroke right up to the maximum stroke?

I am currently making a a trial set up (following the drive bracket layout of John’s (Jss) machine as pictured on Gerry’s Shaper restoration thread). After initially thinking the normal bracket was more useful, I have now changed my mind. His machine has a V notch and does away with the short pivot.

I’m hoping I can use a ratchet gear with several more teeth to reduce the minimum feed. I reckon 35 is achievable, perhaps even as many as 40. I am not planning on changing the feed screw and nut!

So, comments and experience please, starting with “is it too coarse?”, “what set up your machine has?”, and responses to the questions above.

TIA.

[not done it yetParticipant @notdoneityet]

A discussion of the Drummond Shaper auto feed design

[IanTParticipant @iant]

NDIY,

On my (powered) Atlas 7", I prefer to keep the auto feed pre-set at 5 thou (the slowest rate – which is obviously slower to traverse the tool). A smaller feed enables a deeper cut, a heavier feed requires a lighter cut (in simple terms the volume of metal removed remains the same). So I use a lighter feed and adjust the depth of cut to what feels right for the material and finish required.

On my Adept – because both hands are busy working it – I have to set the depth of cut before each pass (so that's the fixed feed) and the 'cut' is adjusted by the 'feel' of the cross feed – so the feed situation is reversed from the Atlas. And of course the stroke rate is entirely a manual 'thing' on the Adept (and Drummond) – frankly I've seen videos of some folk really pumping away much too fast…slow and easy is better.

So 6 thou (and a bit) doesn't sound that fast a feed – I'd simply use it and just finesse the down feed to suit what you are cutting and the finish you need. Of course, the tip radius should reflect the feed rate you are using to get a reasonable finish. – or just use a finishing tool on the final pass.

Regards,

IanT

[BazyleParticipant @bazyle]

It goes hand in hand with depth of cut. So the courser feed affects the sensible depth of cut to use without causing other problems, or just increasing wear.
With a hand operated machine there will be some monkeys who want to show how tough they are by using hefty cuts but I try to keep to 20 sq thou per cut.
The shock load as the cut starts is one of the problems likely to move the stock if you go at it too hard. I have a nice round ended cranked tool with a skewed face so the cut goes on gradually over a few thou so it is smoother to operate.

I occasionally think about improving the ratchet both wheel and the detent but the diameter has to be small to allow the slide to run over it which doesn't help.

[richardandtracyParticipant @richardandtracy]

I will confess on my Boxford I have no idea what the feed is in real units, it's all labeled up in 'thou' and I don't use imperial. Set it up to 'as small as it'll go' and leave it there.

Regards

Richard

[not done it yetParticipant @notdoneityet]

I only used thous. because the shaper is really old, and metric hadn’t been invented in Britain back then!

A Boxford is mechanically powered (not handraulic or manumatic), by an electric motor? It is easy to load those up to full capacity and they will run all day long. I wouldn’t! Slow and easy is what is needed for me!

As a round figure 6 1/4 thous. would be 0.15mm (0.158, more precisely).

What I am asking, of the users, is whether more than one setting is accomplishable, among other things. I think users of hand shapers, in general, would be OK replying on some of the points, but powered shapers are a different ball game – or at least in a different league.

[BazyleParticipant @bazyle]

I'd say the 6 thou is the max I'd want and would then like some finer ones. So if you can make a finer feed then you would have room for more than one rate. I wonder if it is possible to have two half tooth offset wheels with two ratchets so each stroke moves only half a tooth and alternate strokes use alternate wheels. Thus keeping the same diameter and tooth size.

[not done it yetParticipant @notdoneityet]

Bazyle,

Can you get a feed of 12 1/2 thous., or even 20 thous., with the standard set up? And what ram stroke will these operate over? Can you alter the rotating pin height, to change how long or short the stroke needs to be to get one, or two, teeth feed?

[JssParticipant @jss]

Hi ndiy , sorry for the delay in replying, I'll pm you with sketches of the drive on my Drummond shortly. But in answer to your query I can get the movement on mine to vary between one tooth and four teeth depending on the travel of the ram and the position of the pivot in the slot on the drive plate. The cross slide moves about 5thou per tooth. The maximum I normally use is 10thou per stroke.

Regards, John.

[roy entwistleParticipant @royentwistle24699]

On my Drumond, depending which way i'm cutting ie left to right or right to left , the cross slide moves on the cutting stroke or on the return. I don't notice any difference in the finish. I can also get it to move just one tooth.

Roy

[JssParticipant @jss]

As mine has a slightly different drive to other Drummonds here is a sketch and pics of the drive dog and drive plate for anyone who wants to copy them.

Regards, John.

Edited By Jss on 19/01/2018 18:53:33

[not done it yetParticipant @notdoneityet]

Thanks, John.

I’m sure it will help us make the little gems even more amenable.

I’m not one to simply set it up “as fine as it will go and leave it there”.

Roy,

With a simple pointed tool sharpened on both sides, I would agree that the cut would be the same either way of travel. I’ve not yet got a range of cutters, but I expect roughing and fine finishing might need different approaches and a cutter sharpened to cut optimally may not cut the same in both directions (think here left and right handed cutters for a lathe, per eg).

[Martin NewboldParticipant @martinnewbold]

What is this please?

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