Milling Angles, How Do You Do It

[Paul Alciatore]

Yea, you should have put it in the oven overnight first.

I made a dovetail straight edge by scraping a piece of cast iron that had been milled at an angle. It came out nice and did the job I asked of it, but when I went to use it again 6-9 months later I checked it on a plate before use and found it had about 3-5 tenths bend in it. Had to re-scrape it flat again.

[danlb]

I've used angle blocks (such as these from Shars) to establish the angle while clamping work to the table or the vise. If you stack them you can get angles from 1 to 90 degrees.

Dan

[MrFluffy]

I dont have nod on either of my milling machines, maybe I need to join the big boy leagues by getting a little j-head bport or something. The Arno with the 40 taper spindle has rotation but only in the X, and the bridgeport is a rigid ram cnc model.
When I dont use the sine table or its something too big for the table (like a whole engine block) that I want to machine in one fixture, machining nests into a surface using the Y traversal and clamping to them works well for me too. If your just doing this for a single gib project, this is probably the most efficient way of doing it. You can support any small overhang with machinist jacks as another poster indicated already too.

I've been meaning to build a tilting table big enough to fixture cylinder heads off inline-4's on it to do porting and stuff, and that's slowly coming to fruition with a smaller milling machine bed as the trunnion span moveable surface, which I hope will give me cnc porting capabilities too and I can leave it set up on the bport permanently. I'll take some shots when its finished, I'm using a lathe headstock from a small industrial capstan lathe as the trunnion point.

[epicfail48]

So it seems like the general consensus is nod the mill head if you can, clamp to a sine plate/angled blocks on the table is a runner up, and an angle cutter is the method of last resort.

Looks like a sine table/vise is in my near future, although I'd probably have to wait on the accompanying gauge blocks. Luckily for the type of work I'm able to do, shop made would be more than accurate enough

[BCRider]

For those of us without a nodding head I started wondering about the idea of an extra long sine plate we could use for this sort of work. While starting to write up how I would build such a thing I started to wonder at using a cheap sine table or two or if anyone makes an extra long sine table.

So now I'm wondering if TWO OF THESE could be aligned well enough to do the job we require. If two side by side isn't long enough then a longer heavy bar stock machined as best we can could act as a sort of "mini pallet bridge" between the two angle plates to give us extra support.

The trick would be to come up with a combination of modifications and procedure to allow for rapid and accurate setting up of the two plates to each other. But that seems pretty doable with a bit of thought.

The assumption here is that we would not be looking for repeatable "minute of angle" but we should be able to replicate setups within half a degree with decent consistency.

[MrFluffy]

My sine table is about 18 inches long, thats enough to get things well clamped on but still be man* handle-able onto a machine bed and to move between machines easily by hand . The trunnion table is a warco mill bed, it needed the extra X to get a stepper alongside the slots to mount a 5th axis on. Don't know if that helps...

*provided your built like shrek