A very small Shaping Machine ...

Hallo Michael. Sorry I've been off-line over the weekend, so I have only just seen your posts.

Yes, I had in mind the Base Circle articles with respect to cutting involute gearing. I'm sure most people (with Shapers) are already aware of this and the other available shaper literature. Having an Atlas Shaper (and MF Mill) I'm naturally a member of the Atlas Shaper and Milling Group (on Yahoo) and there are quite a few Shaper-related PDF docs there for download should anyone choose to join the group

With respect to automating the Adept, there have been several articles published that used a mechanical 'pawl' type arrangement to apply table feed on the back stroke. I had already considered a stepper-motor drive as a simpler alternative to these purely mechanical solutions. Gaining the 7" Atlas put all that on the back burner. However, in theory it would then be just a further short step to have a stepper controlled 4th-axis and with a very simple tool profile - pretty near perfect involute gears could be cut if the motors were synchronised correctly.

I also read Dave's description of his powered Adept with interest. I suspect that the question of rigidity is very much linked to the size of cut being taken, which in turn may well be influenced by the size of work undertaken (e.g. it gets pretty boring taking small cuts if the surface being worked is large). My solution was to get a larger shaper (which would still be considered a toy compared to "real" shapers like the big Cincinnati's) for surfacing and to take the No 2 "down-scale".

Anyway - I'm pleased that you found my feedback interesting. Let's see how these ideas develop over time.

Regards,

IanT

Just a little brainstorming... A sliding microtome is a self-feeding manual shaper (Oops, it's a planer) that takes very small cuts. A rotary microtome cuts in an arc, but also has a self-feeding mechanism.

Just some ideas.

Regards,

Bob

Thanks for the comments, Ian [and everyone]

I have quite a lot to ponder before I start to draw anything; but there is one particular issue ...

Can anyone suggest a very compact arrangement that would positively lift the tool on the back-stroke?

I am starting to worry that a conventional Clapper Box, which allows the tool to drag, may cause damage ... it's perfectly adequate for typical work on Cast Iron, but I am hoping to produce accurate details on Brass.

Grateful for any thoughts

MichaelG.

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Bob,

That's spooky [and thus very seasonal]

I am about to acquire an old Sledge Microtome which [if it is too far gone for restoration] may live-on as the base of this machine ... and I already have a Jung Rotary Microtome under restoration for its proper purpose.

We are obviously on the same wavelength.

Thanks

MichaelG.

Micheal

Just tonight I was looking through MEs from 1911 - 12 era and someone was suggesting a means of lifting a tool slightly on the backstroke - a solenoid.

Keith

What about using a solenoid to lift the tool?

The only shaper I have ever used (an Alba in school metalwork) had a clapper box so the tool dragged on the return. There is no reason that your tool (bit) has to be hinged, it could just slide vertically and be held off the job by a solenoid.

Probably and understatement to say that some development work might be needed! You would have to ensure the cutting force held the cutter in the right registration every stroke, also not get jammed as a small solenoid wont have much power to 'unstick' it. Actually a simple solenoid can produce relatively high force close to the end of the stroke and you can use the mass and inertia of the plunger as a 'mini hammer' to break the sticking faces.

Ian P

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Thanks for the thought, Ian ... but I can't see how to make a Lift Solenoid arrangement "very compact".

If the Clapper Box on this little machine is more than 40mm wide overall, I shall be surprised.

My current thinking is to have some sort of pushrod running through the Ram and the back of the Box ... and this could probably be actuated by solenoid.

Does that make sense ?

MichaelG.

I think a mechanical 'clapper' style box could be made to work in the way you'd like if it was sprung Michael.

I haven't sat down with paper and pencil but an 'upward' extension to the clapper that was pushed forward by a push rod (activated by the ram handle) which therefore held the clapper down on the forward stroke and which released the clapper on the back stroke might be do'able?

I don't think this is a new idea but I cannot find anything that references it at the moment. In some applications the use of a clapper "lifter" was also advised. From memory, this could be as simple as a domestic 'hinge' (folds in one direction but not the other) attached to the clapper box.

Regards,

IanT

I have a Karl Anderle shaper which has a tool lifter. A pivoted tool post fits in place of the normal clapper box/slide assembly, an actuating lever fits on this and to a crank further back along the ram, the crank contains a friction clutch, the tool is lifted and dropped by adjustable stops acting on a lever attached to the crank.

Dave

If you want something REALLY compact then fit it on the back of the tool

A collar round the tool and a widget down the back

IanT, daveb, Ady1

Thanks for the thoughts

I must have a look at the Karl Anderle arrangement

MichaelG.

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Edit: just found this rather nice video of the Anderle shaper with Hydraulic copying !!

Edited By Michael Gilligan on 30/10/2013 07:41:23

This one looks to have mechanical tool-lifting

MichaelG.

Hello Michael

I have been pondering your quest for a small shaper design. I think one could be made with castings made from epoxy concrete, otherwise known in industry as mineral castings.

The same processes I posted on the write up here on the MEW forum for the Epoxy Worden could be applied to this design.

Below are a couple of rough concept sketches of a small machine. The base footprint in as drawn is 200 x 300 Although It can be made smaller if you only want to work on a 100mm cube. (In fact the whole machine needs to be refined), I have only spent a couple of hours on it so far, clearly there is work to do.

The frame and top slide coloured green, and the cross slide coloured mid grey could be epoxy

I have placed the ram on linear shafting and linear bearing blocks for ease of construction, They could be replaced with dovetails for those with the right equipment to make them. They sit on a 12mm metal plate to make attachment and adjustment easier.

the cross slide and tool slide / clapper box are only shown schematically at this stage. They also could use linear bearings or dovetails?

The ram would be driven in the usual way via an adjustable crank arm. It is also shown schematically. It would be great if someone had plans for a full size crank mechanism, it would save a lot of time reinventing the wheel.

Being such a small machine a litre of epoxy should be enough to make it. For those with reasonable woodworking skills the patterns and formwork would be no problem A square metre or two of MDF and a tin of body filler to make the chamfered corners and some sandpaper would suffice.

The various steel components are within the capability of a bench lathe. and ideally a milling machine or a mill drill.

Oh.... and some quality enamel to make it smile.

Regards
John

Edited By John McNamara on 30/10/2013 15:17:03

John,

Lovely work, thank you

I seem to have several options ... here presented "in order of appearance"

1. Build a very small Shaper Head "module" which can be attached to the various machines or brackets that are already in my possession.
2. Buy a small Shaper and build a "minifier" of some description, that converts it to do very small work.
3. Build a dedicated "very small shaper" around the remains of a Sledge Microtome.
4. Build a dedicated "very small shaper" using Epoxy Concrete where appropriate.

I am currently concentrating on the design of [1], simply because whatever work I do for that should be "transferrable" to the other options.

If I do build a dedicated machine, then I am strongly in favour of the Epoxy Concrete idea ... I remember being very impressed by the work they did at Cranfield in the mid-1980s.

Thanks again for your contribution

MichaelG.

If anyone wants to try making a hand operated shaper, one possible starting point would be the Peter Robinson Slotting Tool. College Engineering Supply provide the base casting and drawings.

It is meant to fit on the Cross Slide of a 7 Series Myford. Mine now uses a raising block for use on my larger lathe., and would need a lot of add ons to provide cross and vertical feeds. But for the keen and / inghenious, such things will merely be part of the challenge. At the risk of being naive, a clapper box to carry HSS tool bits should not be too difficult a project.

Being me, I would want to make up reversible ratchet and pawl mechanisms for the feed!

Any way, I hope that you eventually find / modify / make a device that does what you want.

Howard

Thanks Howard,

I will have a look at the Peter Robinson Slotting Tool ... 'though it seems increasingly likely that I will use commercial Ball [or Crossed Roller] Positioning Slides for the Ram.

MichaelG.

Howard,

Is this what you meant ?

MichaelG.

Hi Michael,

Yes that's the one. It will need quite a bit of extra work to add the feeds to the finished, or modified article , if you choose to go down this route.

I have kept thinking about a small shaper, but have not obtained / made one because:

1) For what would I use it? (Once in possession, no doubt many uses would be found).

2) Where would I store / use it in a HEAVILY congested 2 metre x 3 metre workshop?

Don't say "on a shelf", or "under the bench", those spaces are already filled to overflowing. The only reason that the shelves don't collapse is because they started out as the barge boarding on a neighbouring house!

Good luck with your search!

Howard

A four inch shaper is not really all that small, I have most of a 1 inch shaper sitting on the desk in front of me right now. Mind you that is a scale model rather than being intended for actual work. I was going to submit it as a construction series but there seems to be little point in doing that.

But actually I wonder how important it is for the shaper to be that small anyway? I have a 6 inch Ammco machine that I think would do the sort of work required. I also have a 10 inch Alba, which I used to do the dovetails and the bed for the Stuart Turner lathe model, and also the dovetails for the ram on my own design model shaper. A quite large machine can do quite precise work provided it is in good condition, which fortunately both of these machines are. Provided the main slideways are in good condition, the main limit on a shaper is that the clapper box inevitably is not as rigid as a solid toolpost. For some work you can of course lock the clapper box. So unless the space is a consideration it might actually make more sense to look for a standard machine and if necessary refurbish it, than to make a machine from scratch.

John Olsen

John, whilst I don't disagree with you with respect to what a larger shaper can do (or it's potential accuracy) I think there are a couple of other considerations here apart from just the size.

As I've stated, I have both a hand shaper and a powered one. Whilst a powered shaper is generally a very safe machine it can almost lull you into being a bit too familiar with it (and then it can be very dangerous). So I am beginning to see that some things are better done on the hand shaper, where I can for instance "nibble" at things in a more controlled (e.g. safer) way - something that I wouldn't really want to try on a bigger machine under power.

I am also looking at a good way to limit the stroke by settable stops (for engraving dials for instance) on the hand shaper, again something that I wouldn't really try to do on a powered machine.

So yes, for a good finish & sizing work (be that flat surfaces, gib pieces, dovetails etc) a powered Shaper is great but for small work that is more akin to engraving or for what I think of as "shaving" parts then I think a smaller (shaper-type) hand powered machine might be preferable and much safer

Regards,

IanT