Problem- Alternative clamping.

[Zirok]

Hi

As you can see in picture, i have fixture (shown in dark blue colour). I clamp them with a parallel plate (green colour & through 2 studs onto the plate which directly clamp the T nuts (shown in light blue & red colour)

This is intentionally done to save space...because strap clamping will need more space.

Can anyone suggest any more idea to clamp the fixture & save space...

Need suggestion.

[metalworkz]

It is not clear to me what area you need to machine and what areas need to be clear? There are other means to clamp the fixture but more information about the actual part size and shape being machined would help. Also will you machine one piece at a time or multiples?

Regards,

[Zirok]

The Blue Area is machining area & the Green Is the Parallel block on which the Blue Portion is clamped.

Zirok.

[rowbare]

And how is the machinable part is held to the parallel block? How big are these things? Why is saving space so important? Are you trying to make several at once? How big is your mill table?

There are a lot of really smart people where with a lot of experience fixturing but you've got to give them something to work with.

bob

[metalworkz]

Hello,
I guess you have bolted the blue part to be machined from the bottom of the green parallel and are bolting the green parallel with studs and nuts on the top?
If you just need the sides clear for easier access with the tool to machine the blue section the holes for the nut can be counter-bored and then the nut and washer will be recessed below the surface, or a hex head socket bolt and washer could be substituted for the stud, nut and washer. This will keep the fixture much the same as you have shown it. If the part is indeed held to the fixture with screws etc. you could make a larger fixture plate and nest the parts on that plate which would only need to be clamp with sufficient bolting locations to hold it flat on the worktable. I hope my guess is not too far off but with so little information to go by there is not much choice.

Regards,

[Zirok]

Hi

Your assumption is exactly right. I bolt the blue part from green part (Parallel Blocks) & a stud assembly is used to clamp the parallel blocks.


The problem is not the height of stud (so as to allow access to the blue tool...), but the problem is extra space used as highlighted in the attachment. It uses a space of 40 * 40 mm & i want it to be reduced.


Any other idea of clamping such parts which accomodates less space.

Ash

[ImanCarrot]

What's the material? is it magnetic?

[rowbare]

You still haven't told us if you are trying to setup an array of these to machine at once. I assume so since you are concerned about the spacing.

You have an advantage in that you can grip the work from the bottom. By far the most efficient use of space is to use a large plate and attach your work pieces as close together as your cutter size will allow. Then you only need one set of attachment bolts to hold the fixture to your table (corners and perhaps the middle, as many as you need to keep things flat). Layout a set of parts, attach the plate to the table, zero and align it and let it run.

If you were doing them one at a time, clamping the holder plate in a vise would be the easiest. It would also make for quicker changeovers. Set up a vise with a production stop and some spring loaded parallels.

You can also check out http://www.miteebite.com/. They have a lot of compact work holding solutions for use in fixture plates, t-slots or vises. They also have a product called Mitee-Grip that might be of interest to you.


bob

[JP Hardinge]

I just bought a CNC 3 axes vertical mill, and think I will buy 5 low profile Palmgren drill press vises to clamp across the table and be able to make a decent run of parts with one cycle.

I have a Pamlgren low profile 8", and it's remarkable how solid and accurate a vise it is. More than fine for my needs.

[Zirok]

Actually looking for some alternative clamping other than bolts & studs which consumes space.

Hey, but dont recommend anything costly such as Vaccum clamping and so on.

[metalworkz]

Are the parts you will clamp triangular in shape to begin with or are you cutting them to that shape. You may be able to just use a fixture plate(say .25" 6061 T6) and cut the profiles in the fixture to hold the parts snugly when the plate is clamped to the worktable. Then there are no protruding studs or bolts and you can nest many parts quickly on the table. It depends a lot on the shape and features of the parts you need to hold.

Regards,

[rowbare]

Originally Posted by Zirok Actually looking for some alternative clamping other than bolts & studs which consumes space. Hey, but dont recommend anything costly such as Vaccum clamping and so on.

Man that doesn't leave us much to work with ! There are only so many ways to hold a workpiece down. If you can't clamp from the top, then your options are basically: bolt to a large fixture plate from the bottom, vacuum, freeze clamping, wax, mitee-grip, crazy glue.

An other option is to use stock that is extra thick, machine the top side, flip the workpiece over and face the excess material away.

That or do your operations in multiple steps.

Also you still haven't told us why it is so critical to minimise the hardware you use.

Here is some research you can do:

http://books.google.ca/books?id=6UFh...page&q&f=false

http://books.google.ca/books?id=xPDA...page&q&f=false

Pages 19 forward are a part of the preview and lays out work holding principles. It is worth the read.

bob