|Project by Lumberpunk||posted 03-03-2014 04:15 AM||6661 views||48 times favorited||11 comments|
I had a couple of smaller workpieces jump out of my hands while working on the router table in the last few weeks, no damage but certainly raised my heart rate. So I built this clamp that lies flat and has handles and allows me to route small pieces while keeping my hands a safe distance from the bit.
The body is 16 inches long 1 3/4 inches wide and 3/4 of an inch thick and is made of birch, the screw support and fixed clamp face have a 3/4 inch tenon glued into the guide channel for the moving clamp face. The tenon on the moving clamp face was cut at the same time as the supports and then trimmed with a shoulder plane until it moved through the channel easily.
The screw is 5/16th threaded rod but I am wishing I had used 1/4 inch so it would fit the inset nuts from my parts kit to make a wooden handle for the screw, in the meantime the line of bolts works perfectly well. The rod sits loose in the fixed face, has a mortised in nut in the moving face and a lock nut at the screw handle end to stop it sliding out.
The sliding jaw face is slightly (under 1/32nd) tapered so it aligns with the workpiece under clamping pressure. The jaw faces have 150 grit sandpaper glued on for a firmer grip on the workpiece.
The handles are 3/4 inch dowel in whatever “hardwood dowel” is, they have threaded inset nuts in the handles that screw on to 1/4 inch bolts that run through the bar, easy to remove if the are getting in the way.
The workpiece in the pictures is about 3 or 4 inches long and 1 3/4 inches wide, way too small for me to take near a profiling bit normally, especially when I have so much airspace around the bit. With this clamp it was no problem, my fingers always felt safe and the extra weight of the clamp gave a nice feeling of control to the whole operation. You can see the chamfers in picture 3.
If I had to do it again I would make the piece 1 inch thick and do a sliding dovetail instead of the dado for the guide channel as I notice the sliding jaw climbing out of the dado a bit when under pressure and bending the screw. I am thinking the dovetail will prevent that but I would need the extra thickness of stock ‘cause I’m not going to buy a thinner dovetail bit than the one I’ve got just for the one (unpaid) project. The other thing I would do is make at least 4 at once, thinking without the handles they would make a sweet little assembly clamp.
As a bonus my wife thought I was talking about a clamp for my new spokeshave. I had been testing it but found my bench got it the way a lot when clamped in the tail vise. When she got confused a light went off in my head and this is the result, I call it “Vise in a Vise”
Hope this will inspire some others out there and maybe even save a few fingers (we’ll never know)
2 coats of BLO :)
-- If someone tells you you have enough tools and don't need any more, stop talking to them, you don't need that kind of negativity in your life.