Perfecto 5” hand shaper

[Roderick JenkinsParticipant @roderickjenkins93242]

When using my Perfecto to slot a keyway in a gear I have to cut on the backstroke otherwise there is a tendency to dig in. I have added a screw with a tapered end that locks the clapper shut:

Stay well,

Rod

[not done it yetParticipant @notdoneityet]

Posted by ega on 20/06/2020 09:01:12:

NDIY:

Did you mean the first photo in the Wiki? Hard to be sure but it was not clear to me that the tool point was immediately below the pivot point.

……

As I wrote in my previous post on this – I am not to sure of the ideal position for the cutting tip. I have a comprehensive guide to shaper use somewhere – likely on another tablet – which explains all the nuances of shaper usage.

It is something to do with tendency for potential dig-ins (if anything flexes?). Too far forward and the dig-in would proceed and cause trouble, whereas in the correct position the cut would not be compromised – too far back and the cutter might ‘skate) over the item.

I’m not going to search for the tome unless/until I need to refer to it again for my own handraulic shaping, but it is clear, from that pic, that the cutting edge can be moved further back if necessary.

[John HinkleyParticipant @johnhinkley26699]

I have made a similar keyway slotting tool for mine based on a design by Stefan Gotteswinter. (This is beginning to sound like hero-worship!) It's like Rod's, utilising a hole in the clapper box drilled by a previous owner, which I tapped and it's dog-point tip locates a hole in the toolholder block. The cutter holder is angled down by 5° :

And, ega, I've had another look at the video. If you slow it down and watch it a couple of frames at a time, you can detect that the tool does tip, albeit only slightly, though I assume that's dependent on the depth of cut. (Watch the securing bolt head as the tool drops off the end of the workpiece on the return stroke.

John

[egaParticipant @ega]

All very interesting to me as a novice shaper user.

One advantage of the Perfecto for reverse shaping is that unlike full-size shapers the return stroke is not speeded up; and the hand machine has the advantage of being more controllable both as to speed and power.

Rod Jenkins:

I've taken note of your way of locking the the clapper box. Is yours like mine in the way it is attached to the tool slide? (See my post above timed 09:01:12 where I mistakenly referred to "tool slide" when I meant clapper box.)

I will look again at the Stefan G video. Incidentally, I understand that there are some modes of cutting when lifting on the return stroke is not possible and the clapper box has to be locked.

Edited By ega on 20/06/2020 14:20:18

Edited By ega on 20/06/2020 14:21:05

[Roderick JenkinsParticipant @roderickjenkins93242]

Posted by ega on 20/06/2020 14:18:57:

I've taken note of your way of locking the the clapper box. Is yours like mine in the way it is attached to the tool slide? (See my post above timed 09:01:12 where I mistakenly referred to "tool slide" when I meant clapper box.)

Valid point . The pivot pin is fairly large in diameter and a good fit in its hole so that takes much of the stress but a screw fastening the clapper box to the slide under the clapper would be beneficial for working in reverse mode.

Cheers,

Rod

[not done it yetParticipant @notdoneityet]

I remove the clapper box and fit a solid piece into which is threaded a solid bar (with cutter) for cutting Internal keyways. Just have to progress very slowly. Makes no odds which way I cut, I think, but still pulling, not pushing, the handle is better as the machine was designed that way.

[John OlsenParticipant @johnolsen79199]

A few points relating to some of the posts above:

Assuming the clapper box pivot does not have too much slack, the only flex we need to worry about is the projecting part of the tool. In theory, when this bends with the cutting load, it can tend to make the cut deeper. In practice, this does not seem to be a big problem. Keeping your tools really sharp will greatly reduce the cutting load, which will also reduce the effort needed on a manual shaper. I have played with tool holders that put the cutting edge about level with the clamping face of the clapper box, but it does not seem to make a great deal of difference. I've also got a pair of toolholders that were made for a lathe with one of my shapers, they have built in rake, which is all wrong for a shaper but actually works fine in practice.

I have used a goose necked tool, my first shaper came with one, since sadly broken when it fell on the floor. Again, it did not seem to give better results than a conventional straight tool, and actually the geometry would seem to permit more flex in the digging in direction.

If you are cutting on the return stroke with a power shaper, you should ideally reverse the direction of the motor. If it is not easy to do, I would not worry too much, especially if the stroke is short.

There are possible cuts where you might need to lock the clapper box, although mostly you can get the clearance by angling the clapper box. For instance, when cutting a dovetail, the downslide will be angled to the angle of the dovetail, and the clapper box should then be angled a little more, so that when the tool moves it comes away from the overhung face being cut.

regards

John

[egaParticipant @ega]

Yet more helpful advice and information – thank you!

I mentioned a book by "Duplex" but may have been only half right. For general interest, here is a brief extract from Ian Bradley's "Shaping Machine and Lathe Tools":

The tool in Fig 50 was apparently made from one end of a cycle crank, a feat which I shall not be attempting although I like NDIY's suggestion of a custom tool holder.

[Brian OldfordParticipant @brianoldford70365]

Looking at those lovely swan-neck tools got me thinking.

Wouldn't it be possible to make a tool that relieves the cut if the bend of the swan-neck moved the cutting edge further back?

[John OlsenParticipant @johnolsen79199]

That is supposed to be the idea of a swan neck, however there is no guarantee that it will bend in the direction desired. If the tip has too much rake it will try to pull the tool into the job, while if it has too little it will be pushed out. I've found that the best result come from everything being as rigid as possible and the tool as sharp as possible. That keeps the cutting forces low. Flexible things like goose necks will bend in whatever direction the forces pushes them.

The cycle crank type is not too hard to make, the main point being to find a steel crank, since they are mostly alloy these days. The rest is mostly si9mple turning, apart from the square hole for the tool bit, and you could use round hss for that. It is actually a fairly close copy of a commercial type, I have one for my largest shaper, made by jones and Shipman. (the tool, not the shaper.) It lets you adjust the angle of the toolbit, which can be handy, but the bit has to be quite long to be usable. There are also conventional jones and Shipman type tool holders for shapers. The difference from the lathe ones is that there is no built in rake. I have one, but it is too big for any of my shapers, it needs about a 24 inch shaper. My biggest one is 18 inch.

John

[Mark Knight 4Participant @markknight4]

Finally got the handle finished, thanks again John for the drawing, I’m really pleased with the end result

I even put the shaper to good use in order to produce accurate flats on the spheres.

[John HinkleyParticipant @johnhinkley26699]

Nice looking handle, Mark. Glad it turned out so well for you.

John

[Roderick JenkinsParticipant @roderickjenkins93242]

Excellent, much nicer than the original would have been

Rod

[Mark Knight 4Participant @markknight4]

Thanks Rod and also thanks for the handle drawings you posted a few days ago.

Now would you believe it, a couple of hours after finishing my new handle, I was looking through one of my Dad’s boxes of bits and this was in there!!!!!

I managed to get the broken stud out and put it on the shaper.

Much as I love my new one, I value originality more. This is now exactly as I remember using it about 40 years ago in my grandad’s workshop. Oh well, I enjoyed the challenge of making the new one!

[egaParticipant @ega]

Congratulations from me, too!

Perhaps I will now find my original handle.

[egaParticipant @ega]

Congratulations from me, too!

Perhaps I will now find my original handle.

[Author]

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