Fixture for multiple parts & tandem milling example for superb finishes.

[Mook]

This video shows a multipart self compensating fixture that can hold pieces of different sizes. It also demonstrates how tandem milling with both the inside and outside of inserts can double the output. The technique gives a superb finish as the insert only cuts once and not on the trailing edge. Plus the insert chamfers the top of each part.

This follow up 51 station video shows the tool modified to: mill + chamfer + spot drill each part in one second!

[mdhatter3]

First, thanks for the video. Second, I would like to see the cutter and watch what it does in slow motion.

[Mook]

First, thanks for the video. Second, I would like to see the cutter and watch what it does in slow motion.

I comprehensively replied to your comment & hit the + Reply to thread button. I don't know where it has gone though. Did you get it as a message?

[Mook]

First, thanks for the video. Second, I would like to see the cutter and watch what it does in slow motion.

You can try slowing the video down towards the end where it is close up to see the toolpath.

The finished height of the parts is Z0 & the chamfer depth is Z-1. The parts are 0.5mm too long.

The toolpath is:

Rapid over the centre of part 1 @ Z1
Feed to Z-1 to chamfer part 1
Rapid to Z0
Feed X axis to the centre of part 2 @ Z0. Cutting the top of part 1 with the inside of the inserts & simultaneously cutting part 2 with the outside of the inserts. I call this tandem milling.
Feed to Z-1 to chamfer part 2
Rapid to Z1
Repeat.

The second video is the same except a spot drill is fitted into the cutter body and set to spot the correct depth at the chamfer depth.

The tandem milling produces a superb finish as there is no backcutting. I have a few videos to post showing the method to improve productivity & double insert life.
There is another video showing large chamfers on large parts using the inside of a face mill and it shows the huge reduction in the tool travel with this method.

[DIYer]

Thanks Mook! We've added your Multipart Milling Fixture to our Milling category,
as well as to your builder page: Mook's Homemade Tools. Your receipt:

Multipart Milling Fixture by Mook

tags: milling, fixture

[Frank S]

I would be more interested in the holding fixture. It looks like vacuum holding with air ejection. The parts must be part of a huge batch to justify the fixture

[Mook]

I would be more interested in the holding fixture. It looks like vacuum holding with air ejection. The parts must be part of a huge batch to justify the fixture

Hi Frank

The fixture holds the parts using o rings that compress to suit the individual parts. They are compressed by a cam plate moving bronze followers. Each station has a sleeve which can be changed for different component sizes. The cam plate is moved by jacking screws and locked with a pneumatic toggle clamp. Unloading uses a valve lapping rod with a rubber suction cup on the end. Here is a view of the inside, the cam plate can be seen on the left.

[Frank S]

Hi Frank

The fixture holds the parts using o rings that compress to suit the individual parts. They are compressed by a cam plate moving bronze followers. Each station has a sleeve which can be changed for different component sizes. The cam plate is moved by jacking screws and locked with a pneumatic toggle clamp. Unloading uses a valve lapping rod with a rubber suction cup on the end. Here is a view of the inside, the cam plate can be seen on the left.

Hadn't thought of the fixture being made to accommodate more sizes. That is a well thought out fixture you have there. good for possibly millions of parts
I usually say fewer than 4 like parts do a set up work up fixturing above 4 units. when batches can be in the 100s and repeat batches are likely spend the extra time to make a better fixture. when the possibility of 1000s per batch, get crazy and make your holding device as near to fully automatic as possible.