Jig for fitting Screwfix 34mm cam lock dowels and 15mm cam lock

I have gone to some hours of effort, and expense of nearly £30 on buying metal drill bushes, to make two jigs for fitting these dowels and cam locks. In spite of taking extreme care making the jigs, and making several trial joints in scrap material, the joints still don't align perfectly.

Picture of the 3D drawing for jigs attached:


Is there a commercially made jig for these fixings? I've not found one either in the Screwfix catalogue or from a more general Google search. If anyone knows where to find one for under £50, I'd welcome a link to a source of one.

I have an old Record general purpose dowelling jig but it doesn't really fit the bill, and only has bushes for a small selection of Imperial sizes (1/4", 5/16", 3/8" and 1/2") - so no 7mm or 4.5mm, which are both needed for the body and thread of the cam dowels, and no 15mm bush for the cam lock. The 5/16" bush is close enough for the 8mm wood dowels, but that isn't enough.

I'm working on adjusting my jigs to improve the fit, but this is WAY too hard. The fixings are good and well made, and not expensive, but in spite of years of experience making jigs of all kinds for woodworking, I'm finding these very hard to get right.

Or are these joint fixings really only useful for industrial users with computer controlled drilling machines?

 

Did you just use one Cam lock per joint, and two dowel holes? With the cam lock dowel where your pencil is in the image?

 

I may be trying for higher precision than the man in the video. Looks as if he tolerates (or has designed it that way) overlaps of maybe 1-1.5mm (1/16in). I'm trying to get dead flush, and missing by maybe 0.2-0.3mm.

 

I try to work to cabinet making tolerances, and my jig adjusts for material thickness. But I can't get the holes for the bushes precisely enough located. I'm using a drill press of sorts but it has too much play in the bearings, I think.

Trying to fettle the wood pieces to shift the relative positions of the bushes.

I'm still a bit surprised that there doesn't seem to be a commercially made jig for this.

 

Thanks for the suggestion. I've just looked, but they don't have any jigs for this or even similar purposes

 

A (really) small bookcase as a practice piece, and a larger storage cabinet with pull out shelves on full extension runners. The storage cabinet has to be knock down for transport to its destination. [So I can't use Lamello/biscuit glued joints.]

I can probably slightly modify the bookcase design so it isn't so critical to get flush joints, but allow (as I see IKEA do on their bookcases) the sides to project beyond top and bottom by perhaps 2-3mm. That would mask any remaining inaccuracy in the joints.

The storage cabinet doesn't have flush top or bottom. So I'm over-thinking this - thanks, all, for making me reconsider both the design, and my unrealistic expectations about achievable precision.

I just do this as a hobby, so mostly I'm doing at least some part of the process for the first time, like this form of KD joint

 

I see that I could use the Clamex connectors, which I didn't know about. But at £1 each or thereabouts, too expensive, and too big for the small bookcase.

I can't see where to buy fewer than 80 either.

 

The cam lock would be inside , and essentially out of sight. A screw head would have to be (I think) outside, and visible.

But with a slight change in bookcase design, I can get a good-looking joint with the cam lock, just not a dead flush one.