How to Machine Question

[mikey]

I think this would be a simple affair. Just a plate tapped to receive the three bolts to fasten the compound to, and two countersunk holes to pass bolts that would thread into T-nuts in the table slots. The plate only needs to be thick enough to both handle the compound fastening bolts and also accommodate the required height of whatever tool post you mount to the compound. As long as you can get your tools on center height, you're good. I would just use aluminum for this plate; it is just a solid spacer and is more than strong enough for your purpose.

 

[ddickey]

And you generally won't do any hogging when turning your taper so aluminum would be okay, I agree although more expensive than steel.
So three tapped holes for the compound. How will I turn the compound for angles?

 

[Cadillac]

So three tapped holes for the compound. How will I turn the compound for angles?

Isn’t there only two holes for the compound mount? That is why I suggested a t-slot in the upper round section of plate. The bolts to hold plate to the carriage would have bolts at 3:00&9:00. The t-slot for the compound would be two open slots one from 5:00-7:00 and one from 10:00-2:00. That would give you some adjustment for angles. You wouldn’t be able to do 360* with the compound but it would do.

 

[ddickey]

Yes there are.
How would you go about doing the T-slot?
Just a slot for the bolt shank would do. Then you could go with a thinner plate, no?

 

[Cadillac]

Well the plate is gonna have the bolt heads within it so a 1/2-3/4 plate would be enough to contain bolt heads.
How to make the slots. Rotary table on mill offset for bolt location. I’d probably use a endmill the diameter of bolt shank make your cut all the way through. Then I’d change tools to a t-slotting bit like a woodruff cutter but cuts the top and bottom too. You would have to load tool from bottom in slot then in collet. Cut the same path you cut with the endmill. That will give you the clearance for the bolt head. Or you flip the part cut you bolt shank diameter then come back with a larger end mill that will give clearance for bolt head and follow the same path.

 

[mikey]

So three tapped holes for the compound. How will I turn the compound for angles?

Wait, doesn't the compound turn on its base? Are you not going to mount the compound to a base attached to the rear of the cross slide?

 

[Cadillac]

Wait, doesn't the compound turn on its base? Are you not going to mount the compound to a base attached to the rear of the cross slide?

Compound pivots on carriage the carriage surface is the base for the compound. The compound itself just gives a linear motion.

 

[ddickey]

yes that's correct Mike. The compound will turn on the base that is attached to the cross slide via the t-slots.

 

[mikey]

Compound pivots on carriage the carriage surface is the base for the compound. The compound itself just gives a linear motion.

yes that's correct Mike. The compound will turn on the base that is attached to the cross slide via the t-slots.

Okay, I know one of you guys is right ... just not sure which. My compound bolts to the cross slide but the compound itself is locked to a base that allows for rotation. I assumed you had the same arrangement and were looking to mount the base of the compound on a platen of some kind in the rear. If so, then the rotation thing is handled, no?

 

[ddickey]

There is no base on mine. It bolts and rotates directly on the cross slide surface.