Clamping Question

[murwood]

Looking for ideas on how to do the clamping for a small tooling fixture I am trying to design.

The part being machined is plastic angle (L) that has to have 3 different machining steps performed on it.

The part needs to be referenced from the inside of the angle, the clamp(s) holding it down and into the jig post. Think of pushing down and also to the rear of the table. Headroom is tight, about 1" or less during operation. I am thinking about some sort of toggle clamp operation.

Is it possible to apply clamp pressure in 2 axis from 1 toggle clamp?

Any ideas?

 

[???]

Is it possible to apply clamp pressure in 2 axis from 1 toggle clamp?

Yes with the correct head design

 

[Houdini]

Toe Clamps
Dyna Force
Pitbull
Don't know which way your trying to hold the angle, concave or convex, but anyway, hope this helps.

 

[technocrat]

you could also use a pivoted finger as part of the jig to clamp the plastic. Apply the pressure with a toggle clamp to the finger out of the work envelope.

 

[RC Mech]

Toe Clamps
Dyna Force
Pitbull
Don't know which way your trying to hold the angle, concave or convex, but anyway, hope this helps.

Are the actual Pitbull versions any good? My only experience with Mitee Bite is the hexagonal “clamps” and I’ve never been so livid at such a shitty product.

 

[Houdini]

Are the actual Pitbull versions any good? My only experience with Mitee Bite is the hexagonal “clamps” and I’ve never been so livid at such a shitty product.

The hex clamps are no good, I have large fixture with the larger ones, it works ok, but not a good deal, they don't pull down.
I use Talon grips in vises but haven't used the pit bull opposite on fixture.
But for his plastic the smooth brass ones may work.
I would choose something with a flat maximum surface area so it doesn't dent the plastic but holds.

Depending on hold down need a down or forward toggle with a pivot hold down tip would press down and back, but tall device.

I personally when machining smallish angle(like I will be tomorrow)just machine stationary soft jaws flat and square, part in facing over jaw, and tap it down.
Plastic is flimsy though, I'm usually doing Aluminium.

 

[murwood]

Yes with the correct head design

Can you point me to some examples?

From the operators point of view, in front of you is a 1 x 1 square post. Flat top. You place the plastic part (about 1 x 1 x 1/8, 0.032 thick) on the top with the short side down in front. Need to push down and back at the same time.

I am thinking the head design looks like another piece of 90 deg angle material, the toggle clamp pushes down and back at a 45 deg angle, and there needs to be some sort of flexible linkage between the clamp arm and the clamp head.

Am I on the right track?

 

[Houdini]

Can you point me to some examples?

From the operators point of view, in front of you is a 1 x 1 square post. Flat top. You place the plastic part (about 1 x 1 x 1/8, 0.032 thick) on the top with the short side down in front. Need to push down and back at the same time.

I am thinking the head design looks like another piece of 90 deg angle material, the toggle clamp pushes down and back at a 45 deg angle, and there needs to be some sort of flexible linkage between the clamp arm and the clamp head.

Am I on the right track?

Yes, are you machining around the perimeter, or just in the center?

 

[Garwood]

Are the actual Pitbull versions any good? My only experience with Mitee Bite is the hexagonal “clamps” and I’ve never been so livid at such a shitty product.

The pitbull clamps are the only thing I use of theirs. They work really good provided your stock is consistent size.

I like high density fixtures, lots of parts, long runs between loading. Vises are terrible at those things.

 

[murwood]

Toe Clamps
Dyna Force
Pitbull
Don't know which way your trying to hold the angle, concave or convex, but anyway, hope this helps.

None of the Mitebite clamps look to be usable for this application.

 

[murwood]

Yes, are you machining around the perimeter, or just in the center?

First step is to drill holes. Next mill perimeter shape. Last to flip over and mill edge of short lip.

I envision 3 posts, 3 sets of clamps. Posts 2 and 3 have locating pins to help hold part in accurate position.

 

[Houdini]

First step is to drill holes. Next mill perimeter shape. Last to flip over and mill edge of short lip.

I envision 3 posts, 3 sets of clamps. Posts 2 and 3 have locating pins to help hold part in accurate position.

Ahh, cause I was thinking something like this also, slightly modified but general.

 

[???]

Can you point me to some examples?

From the operators point of view, in front of you is a 1 x 1 square post. Flat top. You place the plastic part (about 1 x 1 x 1/8, 0.032 thick) on the top with the short side down in front. Need to push down and back at the same time.

I am thinking the head design looks like another piece of 90 deg angle material, the toggle clamp pushes down and back at a 45 deg angle, and there needs to be some sort of flexible linkage between the clamp arm and the clamp head.

Am I on the right track?

Mount toggle at 45 degrees. Head has 2 adjustable feet that are at 45 degrees. Toggle comes down towards. Corner of the stock and feet contact front and top face perpendicular to faces. You need play in the head so the feet centre. See below A=feet B=toggle