I’ve recently acquired a CNC milling/engraving machine and have a job to do involving engraving on about 50 150mm x 100mm x 3mm plates. Up till now I’ve just been double sided taping workpieces to the machine table but I’d like to get some kind of clamping mechanism to make it quicker – ideally with a quick release to make doing volume jobs the same size as simple as possible. The machine has a t-slot table.

Some kind of flat milling vice like this
would probably be OK but ideally a larger one would be better which I’m struggling to find (machine bed is 500mm x 330mm whereas most of these vices seem to be for micro-mills).

Alternatively I did find an EU retailer selling these things (cam clamps?)
which go into the t-slots and might be ideal. Can’t find the seller now though (and have no idea what the proper name is for them)

I suppose some kind of vacuum table might work as well – I’m guessing this is a higher cost option though.

Just wondering what people use for holding work pieces down really as I’m entirely new to this!

For 50 off I would probably make a fixture: Ali plate bolted onto the bed of the machine, dowel pins for location and then a toss up between edge clamps (like the one in your lower picture: you can get them from WDS) or just cap screws to clamp the parts in position.

Edit: for 3mm plate I wouldn’t use a vice unless I really had to.

Can you do something with toggle clamps. Very quick and easy but might be in the way, depending on the engraving. Cap screws as above would work too, even wood screws into a bit of mdf bolted down if it’s just engraving.

yeah I figured the vices were meant for holding thicker pieces and using them for a thin plate might not be ideal!

Is this what you meant on WDS?
http://www.wdsltd.co.uk/product/4419/cam-operated-edge-clamp-left-or-right-hand-wds-216/[img]http://www.wdsltd.co.uk/images/7823/11/cam-operated-edge-clamp-left-or-right-hand-wds-216/[/img]
Doesn’t give dimensions (without logging in) but weights almost 1Kg and costs over £100 so might be a bit bigger than I need? Sure the ones I found before were a lot cheaper than that.

I don’t suppose you can find a link showing an example of the plate/dowel setup you mention as I can’t quite picture it?

Can you do something with toggle clamps. Very quick and easy but might be in the way, depending on the engraving.

Something like this?
That would probably be OK I think, could clamp the edges of the plate as the engraving doesn’t go right to the edge. A lot cheaper than the QR edge clamps as well.

Hadn’t even thought of cap screws (didn’t even realise that’s what they’re called!), cheap & cheerful, might even be the best solution! I take it they’re subtly different to a hex bolt (EDIT: a quick Google says yes)

This is the sort of thing I was thinking of;

you want some dowels in a plate and two mitee bites

google them turn allen key job done

picture here

We use mats of this stuff.
Really very good but not cheap.
It washes off under a tap so you can still use whatever coolant you need to.
We used to use a sort of cam thing which I can’t seem to find online.
Some of the options shown above are fine for larger bits on smaller machines but not great for smaller work.

Trotec

http://www.mscdirect.co.uk/BCK-32501E/SEARCH:KEYWORD/product.html

get the right sized set of these