Tutorials for lathe items that require work on both sides?

[Anonymous]

I've got what I think is a somewhat simple problem (as far as it being common). 

I have a piece that ultimately will look like this profile 

Notice that the bottom has a brass insert.with a chamfer around the blue and brass

So I figure there are several setups

Setup 1 - insert the blank cylinder with the intention of milling from the small 'front' to the back.

- face, profile, do the grooves and do the finish pass on everything. Remove some of the material by the back, nut not all (don't part)

Turn the piece around in the lathe

Setup 2 - a setup that that recognizes the fixed amount of remaining material on what is now the front, and 'faces' that off, perhaps leaving 1mm

- have it drill a 11 mm deep 5mm hole

Manually insert a piece of cut brass into the new hole

Setup 3 - have it remove the final material and do the finishing passes, and then cut a "v" that is in the middle of the brass/aluminum join (as shown above)

I have no idea how to setup those, especially with the reversing of the material. I don't want to part it off at first because I don't want the piece to drop.

Anyone have the CAM answer? I uploaded the design. 

The final piece that this is a prototype for, would also require additional fourth axis? work to put marks along one of the chamfers to achieve this (they need only be scratch marks every 6 degrees

 I modeled them with a "v" sketch along a path. But not sure what the proper way should be.

[paul.clauss]

Hi @Anonymous

Thanks for posting! I had a look at your part today and have created a screencast showing how I would approach this problem. The screencast is included below:

The final, fourth axis setup is a tricky one, and I don't really think that there is a way to make it work in Fusion. I have explained this in the screencast as well.

Hopefully this provides a good explanation and please let me know if you have any other questions - I'm happy to help!

[Anonymous]

Hi Paul

Thanks so much for taking the time.

There are actually a few differences with the actual part than that example. There is no sharp point by the grooves. and there is actually quite a bit of space between the angled cuts and any other spot. Plus the angle is less.

But that doesn't seem to be the huge issue. 😕

I'd be fine using a simple engraving tool that would typically be used in a mill and make them as simple scratches from a vertical operation that moved straight down. But that may be an issue too. 

I'd guess that getting the stock offsets correct for having turned around the part would be reliant on chucking the part at a known depth on the part? And from that then the stock offsets would work? 

There is the chance that there could be some required milling on the bottom which would mean moving it to a milling machine and it could be clamped such that the already turned side of the piece is at a place where the z zero value would be known, then the remaining material removed, center drilled, drilled, them the brass inserted and that milling operation and then the additional milling done.

Thanks for the info on how to do this!

Scott

[paul.clauss]

Hi @Anonymous,

Thanks for the response - I'm glad the screencast helped you get started!

You are correct in that the stock offsets will require the part to be chucked to a known depth.

For a simplified toolpath for the scratch marks, you could create and pattern a Project toolpath. This may work for you, but will require the toolpath to be patterned, resulting in many lead-in and retract moves at the mill.

Please let me know if you have any other questions!