material hold down clamps

[_Ogre]

i posted this in the plate marker question thread, but figured anyone could use these.
i typically hold small pieces down with chunks of half inch plate i have laying around, this didn't work so well with the plate marker.

i was scribing some 16ga aluminum and no matter what i stacked on the aluminum i couldn't get the material from moving on me. the sheet was vibrating like a drum. i solved the dragging material around problem by buying harbor fright mini visegrips (set of 4 for $7) and welding a simple angle bracket on them.

i do have big hands, but these are micro visegrips

material clamp, sheet clamps, plasma table hold down

(edited pics)

[CNCCAJUN]

Great idea . . .maybe we could all put our heads together along with your idea and create the ultimate material clamp for CNC Plasma Cutters . . .

For those that don't want to weld maybe you could remove the factory rivet and install your little L-Bracket with a shoulder bolt . . .

I like it a lot . . .

Thanks
Steve

[WyoGreen]

Great idea, I was just thinking of a way to clamp my material for my plate marker. You've saved me some brain waves, and lord knows I don't have a lot to spare anymore!

Thanks, Steve

[muzza]

Here's a simple method Dave (DXF) uses in the attached thread.



http://www.plasmaspider.com/viewtopic.p ... amp#p15162

[cutting$burning]

Great Idea Ogre! Thanks for sharing, a simple low cost solution to save time, material, and lots of cursing. Awsome Thank You D

[CNCCAJUN]

An added benefit is a far better ground if you depend on your slats for even partial ground.

Great idea . . .

Steve

[hacnwac]

These are just some crude ones I slapped together in a hurry one day. The main thing I like about these ones is that if measured properly the only thing sticking above material surface is the Height of the wing nut. Sometimes I am not always attentive enough
Mark

[_Ogre]

post your clamp ideas up peoples
i have 10 more of these micro visegrips to modify, they're not worth much for visegripping
i may weld up some similar to muzza posted, by dave (dxf)

[beefy]

Conjured up this design since reading the first post. Please note it's a design CONCEPT off the top of my head, not a cut and tested design. But if it spawns some improved ideas that's good enough for me.

It can be cut out of bits of say 3mm (1/8th) sheet. The black lines are open contour cuts to create tabs, the red lines are fold points, the yellow bit represents the plate, the green is a 100mm high slat.

One benefit of this design is it's low profile and only sticks up above the top of the plate being cut by the thickness of the clamp material itself.

A nut and bolt can be used through the two tabs with holes in. This pull the top clamp down onto the plate being cut. An extra nut could be used to permanently hold the bolt in place in the lower part of the clamp. The bolt also acts as a bit of a handle then.

I've attached a dxf but remember this is just a quick "knock-up" in Coreldraw, and you may want to alter dimensions to improve it.

Where the red dotted fold line is with the slim rectangular opening, the fold will be a full 180 degrees so you end up with a U-shape and the clamp bends around the slat (top and bottom same).

Criticisms and improvements welcome.

Keith

[WyoGreen]

Here's my take on the OP's design. I took a look at the cheap vise grips at Menards, they were total junk, couldn't turn the adjusting screws on them, looked like the holes were taped at an angle. So I ended up with real vise grips, much nicer (of course they were 3 times the price!). I don't put up with junk tools, just not worth it in the long term. Anyway, instead of welding the straps on, I removed the rivets holding one of the pads on, and used a screw to put the strap on. I figured that way the straps could swivel when I clamped the plate down.

DSC_0075.jpg

[btburn]

These are just some crude ones I slapped together in a hurry one day. The main thing I like about these ones is that if measured properly the only thing sticking above material surface is the Height of the wing nut. Sometimes I am not always attentive enough
Mark

If you use Allthread couplers on the lower tubular portion that you have current have a bolt welded into then you could use any low profile screw or bolt and almost nothing would stick up.
Great ideas here.

[hacnwac]

Yes btburn allthread couplers would work but this is what I had on hand. The reason I welded the thread on the square bar was to keep the top half of the clamp from turning while tightening the the wing nut. Any type of nut or fastener would work but with wing nuts its one less wrench or other tool I have to keep track of and pick up.
ark

[_Ogre]

here's a piece of aprox 4x4x3/8'' stainless steel that i needed to cut one more flange out of the drop
there's no way i could have done this without the piece moving or tipping up when doing the touch and go
these clamps work well



even with a long piece of 3/8x5 stock, it has a tendency to drag the torch on pierce slag and rotate the part

[motoguy]

Here's a simple method Dave (DXF) uses in the attached thread.



http://www.plasmaspider.com/viewtopic.p ... amp#p15162

I ordered some HF locking pliers, to duplicate _Ogre's hold down clamps. Until they get here, I'm going to use some of these. I cut a dozen or so of these yesterday. First parts I cut on my machine!

Thanks for the ideas guys.

[motoguy]

i posted this in the plate marker question thread, but figured anyone could use these.
i typically hold small pieces down with chunks of half inch plate i have laying around, this didn't work so well with the plate marker.

i was scribing some 16ga aluminum and no matter what i stacked on the aluminum i couldn't get the material from moving on me. the sheet was vibrating like a drum. i solved the dragging material around problem by buying harbor fright mini visegrips (set of 4 for $7) and welding a simple angle bracket on them.

i do have big hands, but these are micro visegrips





my slat holders are 10 ga fingers bent into angles. they hold my slats 10ga width off the bottom of my water table tray. the angle bracket on the visegrip slides under the slat and holds the material firm. i also tried an inverted T bracket, these L brackets are easier to insert under the slats.



material clamp, sheet clamps, plasma table hold down

I made 8 of these, and really like them. Instead of welding, I too replaced the rivet with a bolt so the bracket can pivot. Great idea. Very useful. Thanks!

[keefe08]

How about these? kinda like what Keith was talking about (wish I'd seen that before we made these). Just slip the little nut on the bottom under the slat, place the angle iron ear over the sheet, and torque it down. Since it clamps the material onto the slat instead of between slats the deflection is minimal, just depends on how much crap is on the top of you slats )
I like the simplicity of the vise grip clamps but our gantry is a low rider and would wack those suckers all day.

[Plasron]

Great Ideas guys, Thanks for sharing