# Help with homemade clamps!



## StumpyNubs (Sep 25, 2010)

I'm making a lot of items that need to be glued up, and the shape makes using tape to hold them impossible. I need LOTS of small clamps. So I'm making my own- about 80 of them. I've seen a lot of wood cam clamps on this site and like them. What is youe experiance with them? Ever make your own?

I also notice that most have reinforcing pins on either side of the mortises. Are these really needed? Wouldn't the hole itself just compromise the integrity of the wood and lead to splitting around the pin?

The photo below is a design by fellow Lumber Jock Div which shows the pins I am referring to.


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## alba (Jul 31, 2010)

Jim,
you can make simple clamps with threaded rod.
I think Div is on.
You could ask him
Jamie


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## GMman (Apr 11, 2008)

These are the ones I use they are mini but very handy I have 25 of them got them on sale for $1 each.
6" long


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## DonH (Sep 8, 2010)

I dont know the answer to your question but I would love to build the clamps. Any plans or references you can point me to?

Thanks - good project and appear very well made.


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## StumpyNubs (Sep 25, 2010)

GHman- I've used those small Harbor Freight clamps and they brake WAY too easy. The larger HF clamps are ok, but those are terrible in my opinion. Plus, I need 80 of them so even at a buck apiece you can see why I want to make my own!

DonH- Wood cam clamps are pretty simple, they're a lot like those metal bar clamps except instead of a screw handle to tighten them you have a little wooden cam lever. The top piece is solidly attached to the shaft. The bottom piece slides on the shaft and when the cam is engaged against the piece you're clamping, it wedges the bottom piece against the shaft to hold. They are not that strong, but for a lot of projects they are great. and because you can make them with hardwood scraps, they're as good as free.


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## Karson (May 9, 2006)

I think the pins you are referring to might be revits that hold the two sides together as reinforcement.

Here are some plans.


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## GMman (Apr 11, 2008)

I see your point Jim 80 is a lot of clamps I have never used that many clamps but I only do hobby things. Nice when you can do your own and save $80 and more $$.


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## StumpyNubs (Sep 25, 2010)

Karson- wouldn't simple glue work to hold the two sides together instead of rivets? Would the rivet holes weaken the wood?


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## 33706 (Mar 5, 2008)

A secret of technicians is to drill a hole ahead of where a surface may crack, or has already started cracking. Once the crack advances to the drilled hole…the crack goes no further. This works, whether the material is wood, plastic, sheet metal, cast iron or aluminum, or even glass! Though myself, I might consider bandsawing the reverse profile in scrap wood to achieve two parallel surfaces to clamp against, with whatever clamps you have.


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## sras (Oct 31, 2009)

Depends on the shape of what you are clamping, but sometimes a quick and cheap clamp solution is a couple wedges.

In the simple case of two blocks glued together, you could glue two cleats down the length of a piece of plywood. Put enough space between the cleats for the blocks to be glued and the wedges. Force the wedges together to clamp the blocks. I hope that is clear enough. Like I said, it depends on your shape.

It might spark a better idea. Like forcing a wedge between your piece and a dowel …


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## StumpyNubs (Sep 25, 2010)

Cessna- What do you mean drilling holes to stop cracks from advancing is common in Airplanes? I would prefer to think they'd replace the cracked part! Great, I may never be able to fly again!


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## 33706 (Mar 5, 2008)

Thanks, *Cessna!* I'd forgotten what the correct term for that procedure. I'm just guessing that the hole was there for that purpose.
*Sras*: I hope you're not going to refer them back to an earlier, ahem, wedge topic!! Congrats on your 1-year anniversary, btw!
If I built homemade clamps like in the illustration above, I'd still prefer to drill holes in the bar and use a tapered removable peg for a positive stop on the tailpiece or possibly some other means of detent, rather than rely on a friction bind alone.


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## sras (Oct 31, 2009)

Hey PK - It did occur to me this morning that maybe I should post a link to that informative and innovative post.

Jim - If you missed out on the end-all discussion here is where to find it!


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## BertFlores58 (May 26, 2010)

May I clarify something here.. The crack, if it is already through then the stop drilling process is no good to use. On board ship,, metals under stress gets a seeping crack. You have to stop the extent of continued cracking by means of drilling at the end of the crack otherwise it will just spread all over. If this is the purpose then it will be good. However in the clamps, the pins are guides and a piece of strength so that it will not be sheared on the glued parts. Rivets has to strength to serve.. 1) shear force and 2) compressing those pieces of joints…. HOpe I share some ideas.


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## SteveMaskery (Feb 18, 2009)

Hi Jim
This is my version:
http://lumberjocks.com/topics/18896
I have some that are 20 years old and still going strong.

In some commercial models I have seen there are pins riveted through, similar to those in the photo, but not quite in that place. They are positioned so that they actually touch the stock, so that when the clamp racks, the pins bite on the stock.

I find that the laminated construction makes for easy fabrication as well as a strong result and no pins are required.


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## BigTiny (Jun 29, 2010)

I think the pins serve two purposes, to hold everything in alignment while the glue sets, and a back-up hold, sort of a suspenders and a belt thing.


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## StumpyNubs (Sep 25, 2010)

Cessna- I was only joking. I've done a great deal of flying (as a passenger, of cousre) and have never been afraid for my life. In a car it is sometimes another matter…


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## 33706 (Mar 5, 2008)

Not that I wish to divert attention away from clamps, but I have an aircraft repair story to tell…I once temped in an aviation terminal for a small airline that specialized in runs to First Nations lands to and from Winnipeg. They had a fully loaded plane with about 25 passengers, all of whom had huge loads of groceries they were bringing back to the reserves. The mechanics were towing a disabled plane into the hangar, and the wing of the disabled plane clipped the rudder and tail of the plane about to depart. The mechanics unhitched the tow-motor and pulled the damaged plane, passengers and all, close to the hangar door, where they pop-riveted some sheet metal over the damaged areas! They waved off the plane, which presumably took off on its flight without incident, despite the crappy repair.


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## StumpyNubs (Sep 25, 2010)

I was on that plane. We all died.


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## 33706 (Mar 5, 2008)

LOL, Sorry, Jim, didn't mean to hijack your thread….Oooopsie!! I shouldn't say hijack in a discussion involving planes, well not if they aren't Stanley planes…
How much travel is there in the eccentric cam on your homemade clamps?


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