Thread: What have you invented?

Some ideas here: Mitee-Bite Products Co.

There are things called mite bites (spelling?) and there are a few homemade designs like this around, if thats the type of thing your after.
Powerful but Simple Wedge Clamps

Dave

Yes Pipeclay, I think the individual jaw approach is handy - I need to modify the idea a bit to suit my rotary table, which only has 3 radial T slots.

Stuart, the thickness varies - often the sort of thing I do begins with a steel plate - maybe 1/4" to 1" thick depending on the bright idea I am having at the time - so I want to skim the plate to make a reference surface for the rest of the project.

Some time back I wanted to re-surface the bottom face of a hydraulic valve block - no place to put clamping blocks - took me 2 days to set it up and 10 minutes to cut it.

In that case there was plenty of vertical room as the block was about 75mm thick, but often I don't have this luxury.

So I would be interested to know more about your low profile clamps.

Yes Brian, the Mitee Bite stuff is cute - I don't actually have any - do you ? I find that hi tech stuff hard to resist, but I seem to get mixed results with it.

Dave, those wedged clamping blocks are something I can relate to - I will have a crack at making some up tomorrow. Like the Klank fellow said, the idea might be 20 years old but you don't see it about.

Thank-you all for your replies and ideas - they are all interesting.

Cheers,
Bob.

Can you for some of this work use a 4 jaw chuck.

Yes, chucks are currently my main way of holding work on my rotary table - and for a some things this is Ok. But for rectangular jobs and odd shaped stuff it is not so good.

I am thinking of making a rectangular table out of mild steel and fitting that to the rotary table - and organising this one with individual jaws, looking a bit like a 4 jaw chuck when the jaws are on diagonals - and more like a vyce when the jaws are on opposing parallels.

And Dave's wedge jaws could be ideal for this.

Cheers,
Bob.

Hi Bob,

Here are some pictures of the ones I am making up. As they are the minimum would be about 10mm. I started making them as the other designs I had seen up until the used a grub screw against the bottom of the Tee slot. They should also allow gripping and angles should that ever be an issue. They aren't finished in that picture(and aren't finished in the shed either). The face against the work and the back edge need to be machine so they are vertical as it it sitting in the picture so that it pushes against the work as it is tightened.
Of course having said all that, I cant guarantee that they will work lol

If I get a chance I'll have a go at finishing at least one tonight.

Stuart

p.s. The bolts are 1/2 UNC

Originally Posted by citybook

- often the sort of thing I do begins with a steel plate - maybe 1/4" to 1" thick depending on the bright idea I am having at the time - so I want to skim the plate to make a reference surface for the rest of the project.

Hi Bob,

What about a mag chuck, or a vacuum table?

Regards
Ray

Originally Posted by citybook

Yes Pipeclay, I think the individual jaw approach is handy - I need to modify the idea a bit to suit my rotary table, which only has 3 radial T slots.

Stuart, the thickness varies - often the sort of thing I do begins with a steel plate - maybe 1/4" to 1" thick depending on the bright idea I am having at the time - so I want to skim the plate to make a reference surface for the rest of the project.

Some time back I wanted to re-surface the bottom face of a hydraulic valve block - no place to put clamping blocks - took me 2 days to set it up and 10 minutes to cut it.

In that case there was plenty of vertical room as the block was about 75mm thick, but often I don't have this luxury.

So I would be interested to know more about your low profile clamps.

Yes Brian, the Mitee Bite stuff is cute - I don't actually have any - do you ? I find that hi tech stuff hard to resist, but I seem to get mixed results with it.

Dave, those wedged clamping blocks are something I can relate to - I will have a crack at making some up tomorrow. Like the Klank fellow said, the idea might be 20 years old but you don't see it about.

Thank-you all for your replies and ideas - they are all interesting.

Cheers,
Bob.

If you have a look on CDCO's website, he sells low profile clamps, set of 6 for $27 US. I was going to make some, but saw those when I was getting some stuff from him anyway, so added them on . Not worth making them at that price! Of course, if you have different size t-slots to a Bridgeport/clone, doesn't help much, although maybe he does different sizes.

Haven't had a need for them since buying them of course , so no idea how well they hold.

Hi Stuart,

I like the flat clamp idea, I wonder if it would be better to reverse the step, what I mean is to make the fixed stop with a step that stops the angled wedge from lifting up at the back.

I could draw a picture, but I hope you get what I'm thinking.

Regards
Ray

Hi Ray,
Think I'm going to need a drawing. Whats going to make the angled wedge lift up at the back?

Stuart

Hi Stuart,

This is what I mean...



As you tighten the clamp it's going to want to ride up at the back, putting a step would
stop that...

EDIT: I guess the bolt would stop it anyway, so it probably won't make any difference?

Regards
Ray

My guess is the bolt will be pushing down on both ends. The reason I put the step in was so the corner wasn't against the table and to bridge the tee slot. I better get my finger out and finish one tomorrow and see.

Stuart

Well I machined the faces off this morning. It seems to work fine. Tightened with one finger and thumb on the short end of the allen key I cant move the blocks by hand. If you turn the allen key around you can tighten it further and I believe the Tee nuts start slipping. The clamping range is something less than 0.4mm. One thing that did surprise me is that when the clamp is undone its not locked against the work.

Stuart

p.s. I've just put a DTI on each of the fixed clamps. Paper or not paper they are still moved. I'd say the clamp is gripping tight enough.

Hi Stuart,
I have been out playing also and have some ideas.

The clamp should be gripping on the table, not depending on the T nut in the slot for grip - so if the nut is slipping in the T slot maybe a longer clamp design that spans 2 slots is needed (for the anchor block, at any rate - the clamping block can be shorter).

On the wedge clamp that Dave found, I realise that there is a slight tendancy to lift the work - ie. the wedging section rotates slightly as the bevelled end sinks toward the table - and the other end tends to lift the work.

So now I think I favour your design - as your block against the work rotates it is turning downwards, which is much better than upwards..

Both clamp designs have a weakness in that they have a thin line of contact with the work piece - ie. the clamp is at a slight angle to the table, so therefore it is not square to the work - therefore reducing the gripping area in contact.

I don't think a small clamping range is a problem - after all, the clamp is positioned against the work before the first block is tightened down.

Cheers,
Bob.