Cam Clamps
Welcome! / Forums / General Woodworking Discussions / Projects / Cam Clamps
- This topic has 8 replies, 4 voices, and was last updated 8 years, 1 month ago by aarontobul.
-
AuthorPosts
-
13 March 2016 at 4:50 am #135574
Very nice old boy but can I pull you up on one thing I feel the cork is unnecessary as the face is flat and will not mar the wood plus the clamping pressure is only minimal as well which doesn’t exert enough force to mar the wood. I think and correct me if wrong you have taken away the clamping pressure by half by cushioning it. Think of it like the soft and hard heads of a rubber mallet, pounding with a soft head cushions the blow which results in a weaker blow but flip the mallet and the force will be much greater. This I discovered with my wooden planes it took several blows with the soft part to loosen the wedge hence when I flipped it two or three blows worked like a charm also flipping the plane and whacking it on the bench works even better.
13 March 2016 at 2:17 pm #135581The cork is not there so much to prevent marring but for the following:
1. Provides grip, especially on irregular surfaces such as corners and moulding so.
2. Sacrificial in the event of errant glue. Much easier to break away cork than to seperated two pieces of wood that have been accidentally glued together. 😉Admittedly, the cork that I used is probably twice as thick as needed, but still works just fine with no appreciable loss in clamping pressure. The cork readily compresses and the clamp reaches full usable pressure long before I run out of cam.
These are light-duty clamps best employed in small and/or delicate work where the typical bar clamp is too large and lacks sensitivity. Examples being box and drawer making and these are a traditional clamp in the musical instrument trade.
I think they will prove to be quite useful in my shop.
13 March 2016 at 2:21 pm #135583Thanks for the update Greg and for correcting me I will be making a set of these soon
From a physics point of view, the cork shouldn’t change the clamping force and, since it is the same size as the wooden face underneath, shouldn’t change the clamping pressure (although it could avoid “hot spots” by conforming to the work surface).
The hammer is different. You swing the hammer, which gives it some amount of momentum. The head hits the workpiece and, over some amount of time, comes to rest. For the hard headed hammer, it comes to rest in the blink of an eye. For the soft headed hammer, it comes to rest in two blinks of an eye. Coming to rest quickly corresponds to more force than coming to rest less quickly. I think you’d also find that the difference in how the force spreads out over time matters for loosening the wedge. Actually, it’s probably the wood vibrating that matters, too.
Sorry…more than you wanted, probably. There are geeks like me hiding everywhere, I guess. 🙂
13 March 2016 at 10:14 pm #135604Thanks Ed I love geeks I actually learn from people like yourself. What you said corrects my mistake. Btw I couldn’t think of that word last night momentum but after a 14hr shift I couldn’t think much at all.
14 March 2016 at 2:10 pm #135624Very nice job. Did you use nails instead of roll pins? Oops, never mind. I’ve just spotted your blog which indicates that you did indeed use nails. Being a bit of a cheap bas…I mean conscientious recycler…I may do the same thing when I get to mine.
- This reply was modified 8 years, 1 month ago by aarontobul.
-
AuthorPosts
- You must be logged in to reply to this topic.