CAM for cover plate and cover plate fixture

The cover plate is made from a piece of 3/8" flat stock, 4" wide and as long as the bracket itself, with the same profile. So not much sense in trying to clamp it at one end. Instead I'll have to clamp it down to something solid, or even better, bolt it down and machine it using sacrificial tabs that can be sawn and filed away afterwards.

Simplest solution is to bolt it to a piece of the same 4" x 1-1/2" stock used for the bracket itself. I reckon that can be held in the vise and the cover plate bolted onto it with 4 x M8 bolts.

First, model up the cover plate with some extra length for bolting down.

Then use this to create a "fixture" ie a length of the thicker stuff the same width and length. Drill through both with 7.0mm drill (good for M8 tapping). Then manually drill out the holes in the cover plate to 8.0mm for the bolts. Once the holes are tapped M8, I can bolt them together, set up on the machine and get machining.

Do the heavy operations first ie boring the large central hole, then the drilling, pocketing and  counterboring operations. Finally, cut the outer profile (leaving tabs) and finish off with chamfering.

The CAM looks relatively simple. Although there are 11 operations, there are although only 7 tools. 

NB: I notice that my tool numbering is a bit suspect. In creating some new tools, I've ended up duplicating some tool numbers. Must fix that or I will risk crashing some tools!!

It's good to have the stock modelled in simulation, with the CAD model also visible. Then you can turn the post-machined stock on and off with the check box and check to see if the final work piece has all the desired (CAD model) features. That's particularly important for the chamfers etc which can be a bit tricky to set up with the correct offsets etc.

This what the CAM simulation believes will result:

And this is what the model looks like:

Let's get it all set up now....