Home made clamp guide plans

[Tiger]

<TABLE id=HB_Mail_Container height="100%" cellSpacing=0 cellPadding=0 width="100%" border=0 UNSELECTABLE="on"><TBODY><TR height="100%" UNSELECTABLE="on" width="100%"><TD id=HB_Focus_Element vAlign=top width="100%" background="" height=250 UNSELECTABLE="off">I have been trying for some time to make a t-square guide which is both adjustable and able to be clamped without resorting to external clamps. So far what I have is a T-square which has a slot running down the middle of it. Inside the slot is a T shaped bit of wood with a bolt in the middle, this bit of wood runs in the slot and the bolt can be clamped down with a wing nut. Theoretically when you want to run a router etc against it, you put the T square over one edge and the move the T shaped bit of wood against the other edge and seucre it with the wingnut. Unfortunately this not secure enough for my liking. The piece to be routed or cut is a little loose. What I need is some means of providing extra clamping, probably some sort of cam. The end result is probably not a lot different from the straight edge guides that Carbatec etc sell but I want to make mine from some hardwood that I have. Any ideas or links to help here?
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[HappyHammer]

Pictures please.:missing:

HH.

[Tiger]

Ok here are the photos.

Photo of the jig, then photo of the components, then photo of the jig in use where it needs a more postive clamping pressure. Tried a bit of sandpaper but still a little movement. Thinking of some sort of cam action but not sure how to build that in, any ideas?

[niki]

Ok Tiger, I'll try...

The only way that comes to my mind now is....

Let's call the stop that you made (the existing stop) "Primary stop".

Make another stop, it can be just a strip of wood at the same thickness as the "Primary stop" with the same bolt method that you are using, and let's call it "Secondary stop".

Cut or trim the "Primary stop" to get two diagonals one at front and one at the back. (see pic)

To clamp the T square, release both stops, let the "Primary stop" front side to "fall" down at an angle so the front diagonal will be straight with the workpice and, the back diagonal will be straight with the "Secondary stop".

Push both stops to the workpiece, keeping the front diagonal "down" and clamp the "Secondary stop"...and now, tight the wing nut of the "Primary stop"...the diagonals will do the rest of the work....

Sorry for the "Lo-tech" drawing, I don't have all those 3D drawing programs...

PS, and do me a favor and change those wing nuts with some good knobs with T-nut :)

Regards
niki
59048

[Tiger]

Thank you for repying Niki. Your idea seems plausible. This would give it some sort of wedging ability, am I right?

I use wing nuts for many things, but for you, I'll change it to a wooden knob :D.

[BobL]

Ok here are the photos.

Photo of the jig, then photo of the components, then photo of the jig in use where it needs a more postive clamping pressure. Tried a bit of sandpaper but still a little movement. Thinking of some sort of cam action but not sure how to build that in, any ideas?

I would prefer to add a longer wooden outer to your wing nut to give you more leverage, like this
http://www.woodworkforums.ubeaut.com.au/attachment.php?attachmentid=27105

A cam is really where you want quick release. Here is a quick and dirty step by step of how I have made some.
http://www.woodworkforums.ubeaut.com.au/attachment.php?attachmentid=59069&stc=1&d=1193796492

Here is what it finally looks like.
http://www.woodworkforums.ubeaut.com.au/attachment.php?attachmentid=59073&stc=1&d=1193799463

I used Steel but one could equally could use a hard wood or Al.

[HappyHammer]

I see the jig masters have replied to your request Tiger so nothing I can add....good luck...:U
Have you seen some of Niki's other posts on jigs?

HH.

[Tiger]

Bob, thanks so much for going to the trouble of drawing the cam plans for me. I think I've got most of it but do you have any more detailed info/links on cam quick release construction? I'm having a little trouble understanding why we perform certain steps in your diagrams. I had thought for a cam, it would be easier to just drill an off centre hole in a circular bit of wood/metal and just turn it with a suitable lever?

[BobL]

Bob, thanks so much for going to the trouble of drawing the cam plans for me. I think I've got most of it but do you have any more detailed info/links on cam quick release construction? I'm having a little trouble understanding why we perform certain steps in your diagrams. I had thought for a cam, it would be easier to just drill an off centre hole in a circular bit of wood/metal and just turn it with a suitable lever?

Yeah I thought so too but it has to grab hold of the piece underneath it somehow and I could not get mine to grip too well when I did that. Just cranking on the cam harder doesn't seem to help. My guess is that method would work if one had really chunky brackets and cams and very close fitting holes and shafts. When I tried it the cam would tilt over and be only touching the base at a point. With the bolt passing right through the middle of the cam the gripping action was right across the cam and much much better. It also makes for a much easier tension adjusting mechanism.

A diagram that shows this in some detail is here (http://www.woodworkforums.ubeaut.com.au/attachment.php?attachmentid=47511).

If you want to do it using your way, supporting the cam on both sides is a way of doing it BUT the adjustment mechanism is more fiddly. Check this out.
http://www.woodworkforums.ubeaut.com.au/attachment.php?attachmentid=48603
The tension adjustment is done by loosening the knurled knobs and tightening/loosensing the dome nut - this works really nicely but requires more work to make.

Cheers

[niki]

Thank you Tiger

I was just thinking that maybe it's better and easier to make the Primary stop as a trapeze (drawing)...that way, you don't have to tilt it before clamping just lower it a little bit below the Secondary stop.

I know that you know that I was joking about the knobs. I was also using wing nuts but when the fingers gets old, it pains so, I "converted" to knobs.

Bob's idea is very good but, I'm not "machined" enough (or not at all) to make it so nice as Bob did so I'm going with the more "Neanderthal" way...:-

Regards
niki

59088

[BobL]

Bob's idea is very good but, I'm not "machined" enough (or not at all) to make it so nice as Bob did so I'm going with the more "Neanderthal" way...:-
59088

Niki, I agree with you, for woodworking jigs I too generally prefer knobs, or at least wingnuts encased in wood. Those 38 mm diameter steel cams I made are designed for locking down 111cc of brutal chainsaw onto my BIL chainsaw mill (http://www.woodworkforums.ubeaut.com.au/showthread.php?t=50374) - these are very different requirements. Those cams also took much longer to make than knobs.

[niki]

Hi Bob

Yeap, you are correct, my wooden trapeze design would not work there :)

You made there a "machina"...very nice...much above my abilities and capabilities.

Talking about knobs and wing nuts, do you mean something like on the pics

Regards
niki

59122 59123

[Tiger]

Thanks Bob and Niki, I'll need a bit of time to digest everything and see if I can make it work.

[BobL]

Hi Bob

Yeap, you are correct, my wooden trapeze design would not work there :)

You made there a "machina"...very nice...much above my abilities and capabilities.

Talking about knobs and wing nuts, do you mean something like on the pics


Correct - The only thing I do different is glue another piece of wood on the underneath so the wing nut is completely covered with wood.