Clamp for MFT

[Steveo48]

OK, I'm liking 80/20 or Item extrusions even better now, but....

If you put a rectangular stiffner between the Kreg clamp and the extrusion say, 3", 4" long, would that possibly spread the force well enough to prevent damage?  What if you put that nifty rubber shelf liner between the table and your work and increase the friction there so less force is needed?

Last of all, you'll have to forgive my unexciting suggestion of an F-clamp ( I know, it's so old school) ;D

Steve

 

[Corwin]

I would think one could just use a piece of wood between the two -- mount the smaller Kregg bracket on a wood base that in turn mounts to the profile with bolts and T-nuts.  That way the Kregg mount interacts with the clamp, the wooden part takes the brunt of the force and the profile is far less likely to receive any damage.

 

[Steveo48]

I would think one could just use a piece of wood between the two -- mount the smaller Kregg bracket on a wood base that in turn mounts to the profile with bolts and T-nuts.  That way the Kregg mount interacts with the clamp, the wooden part takes the brunt of the force and the profile is far less likely to receive any damage.

Yes like a big wooden rectangular washer.  A scrap of hardwood would work really well.

 

[neoshed]

What about making a mounting block out of wood with a t nut in the underside that you could then clamp to the table through one of the mft holes? You could mount a toggle clamp the the block and then clamp whatever you wanted ?

 

[Corwin]

If you want to place the Kregg clamp on the table, you can just use the larger base and clamp in place with your Festool clamps.  That's no problem.  The issue here is attaching it along the side profiles.

 

[gkeas]

I actually dug through my box of leftover stuff and found a couple of pieces of rectangular metal that is pretty thick.  It is about 1.75" long and fits in the width available for the edge profile.  It has a hole tapped into it already (M6) but I can modify that to fit the Kreg screw (I don't know what the thread pattern is yet).  I think this would spread the load sufficiently to prevent the dimpling(sp?) that Corwin experienced.  I'll check it out and report back.

 

[Dave Ronyak]

I actually dug through my box of leftover stuff and found a couple of pieces of rectangular metal that is pretty thick.  It is about 1.75" long and fits in the width available for the edge profile.  It has a hole tapped into it already (M6) but I can modify that to fit the Kreg screw (I don't know what the thread pattern is yet).  I think this would spread the load sufficiently to prevent the dimpling(sp?) that Corwin experienced.  I'll check it out and report back.

That should solve the "dimpling" problem, but don't overlook the fact that torqueing of the side rail will still occur when you apply the Kreg clamp to a workpiece on the MFT top.

Dave R.

 

[Tinker]

I use only the Festool screw type clamps along the edge grooves.  I don't even use the ratchet type clamps along that edge unless for light clamping.  I find that any type of clamp such as the Kregg clamps are very difficult to set the tension exactly. 

You either set to be loose, or tight.  It is very difficult to set exactly to the needs.  i have same problem with those Festool horizontal ratcheting type clamps. (Sorry, i don't have FT catalogue right handy for proper descriptions.) 

Tinker

 

[woodshopdemos]

This red Incra clamp sshould work:

from Woodcraft page.

 

[Tinker]

John, I use that type of clamp for many different applications.  They are very handy.

However, i don't find them usable for the specific problem being discussed here.  To clamp from the side extrusion of the MFT, you just can't get a purchase from the extrusion on the side (horizontal) to the table surface.  The levering end will hang off into space, which i have found to be not very useful as a levering surface except for hang gliding 

Perhaps and extra block clamped into the verticle side extrusion would give a stable surface to clamp against.

As i sit here typing (haven't had breakfast yet, so mind is not funtioning up to full speed) I have come up with an idea to make that type of clamp (as well as the Kreg clamps) work.

Howabout a 2x block nothched as an "L"so the long side is bolted (T-bolts) to the verticle side extrusion and the short side bolted (T-bolt again) bolted into the horizontal extrusion.  The clamps you have shown, or the Kreg clamps could then be bolted into the top of the L-block.  If two bolts are used on the verticle side of the L-block and two into the horizontal side of the L-block, that would spread the load enough to reduce possibilty of distortion of the either extrusion, verticle or horizontal.  The 2x block becomes a base with enough width that the levering end of the incra (mine are blue from Rockler) will be on a solid base. I hope this is clear.

I'll look into this later and see how it works. (atleast after breakfast) For those who might be set up with machine shop capabilities, a metal block might be even better. )

note: i don't think i would use fir or pine for such a block as they would be prone to splitting.  I do have a scap of 2" white oak and a few scraps of 3" hard maple that could be used for such an application and would stand up to many repetitions of such use.

Tinker

 

[Steveo48]

How about a short piect of T Slot aluminum?  Or get a piece of angle iron and drill holes in it to accept t bolts?

John, I use that type of clamp for many different applications.  They are very handy.

However, i don't find them usable for the specific problem being discussed here.  To clamp from the side extrusion of the MFT, you just can't get a purchase from the extrusion on the side (horizontal) to the table surface.  The levering end will hang off into space, which i have found to be not very useful as a levering surface except for hang gliding 

Perhaps and extra block clamped into the verticle side extrusion would give a stable surface to clamp against.

As i sit here typing (haven't had breakfast yet, so mind is not funtioning up to full speed) I have come up with an idea to make that type of clamp (as well as the Kreg clamps) work.

Howabout a 2x block nothched as an "L"so the long side is bolted (T-bolts) to the verticle side extrusion and the short side bolted (T-bolt again) bolted into the horizontal extrusion.  The clamps you have shown, or the Kreg clamps could then be bolted into the top of the L-block.  If two bolts are used on the verticle side of the L-block and two into the horizontal side of the L-block, that would spread the load enough to reduce possibilty of distortion of the either extrusion, verticle or horizontal.  The 2x block becomes a base with enough width that the levering end of the incra (mine are blue from Rockler) will be on a solid base. I hope this is clear.

I'll look into this later and see how it works. (atleast after breakfast) For those who might be set up with machine shop capabilities, a metal block might be even better. )

note: i don't think i would use fir or pine for such a block as they would be prone to splitting.  I do have a scap of 2" white oak and a few scraps of 3" hard maple that could be used for such an application and would stand up to many repetitions of such use.

Tinker

 

[Tinker]

I was thinking in terms of what I have lieing around in my shop.  I keep all iron scraps out in the barn with tractors and mowers.  I hate to walk that far when i finally get a chance to play in my wood shop 

Tinker

 

[Mike Steele]

Another option is available from Woodpecker:

Woodpecker Universal Track Clamp

I bought two of these and they do fit the extrusions.  They work well for securing wood for making cuts or for use with the Domino.  However, they do not work well if extreme clamping pressure is needed.

I did not notice any affects on the profile after use, but if concerned, they can be easily modified as the clamp is held in place by a 1/4-20 bolt that can be removed by unscrewing the star knob. 

Biggest drawbacks that I have seen is that the anti-marring rubber on the clamp face has a tendency to grip the material as the clamp is being tightened, causing the material to move. 

Also, I am a bit concerned that the T-handle for the clamp will break off when loosening the clamp if too much torque is initially applied.  Under these circumstances, the only thing that appears to be moving is the handle itself.  The solution is to loosen the star knob first, which allows for clamp rotation, then the T-handle.

With that being said, I plan on buying a few more of these, as they are definitely handy.

Hope this helps.
Mike