Hi rstermer
ANy hardwood dowel will do the job but I do like Oak over the others.
Drilling the hole,,,I try and drill them about 1/4" from the edge,when the cam is used the screw hole is on the backside of the cam so to say you have alot of stock between the screw and the edge,plus because it's dowel you are drilling down in with the grain.
I have not cracked one yet and most are drilled down to with in 1/4" of the bottom of the cam...
To set the cam in place ,it just needs to cam in and lock the part in place,it takes no presser at all to lock them in place because of the cam action...
"So it is fairly complicated to get it just right. Yes?" No,, it's very easy to set them and lock them in place,,
The holding jig you posted (link) the cams could be used on it,just a quick turn on the cam and it's locked in place the screw is just a device to keep it from backing off the lock down...
Just the nature of the cam ,more you turn it (load it ) the more it can hold.
They also work great for picture frames, boxes,templates, etc. anything that needs to be held in place till the glue sets up...a quick right angle jig (see below) and some cams can lock the frame/box in place in a heart beat...
Do this pull out some 3/4" dowel rod you have on hand or just about any size you have on hand , cut off 8ea., then take them to the drill press and drill some holes for the screws you want to use...besure to counter sink the holes for the screws, find some scrap plywood and put a block of wood in the center of the scrap plywood and put down 4 cams and then 4 more, then try and move the block round you will be amazed how well the cams work and how easy they are to use...
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