Trouble chamfering parts

[scottp55]

I've tried about everything on MDF and solid wood,and wasn't totally happy until we went HDO and then thin lacquered that 6 times, but we still have to finish what we start the same day or button hole CS is off and very visible(to me).
Like Bob's suggestion if it's a repeat/quantity type product.
Maybe look into those copper cap/self centering jigs/separate Z-3 routines I've seen people use?
scott

[EricSchimel]

Yeah, I'm wondering if that's going to happen to this jig. At least I put enough holes in it that I can check it before I use it. I was thinking of making another out of Baltic Birch and sending it to my finish shop to be sealed up really well. The other thing I thought of was actually making it out of HDPE since I now have a lot of it around....

[bill.young]

Moisture expansion and contraction is certainly an issue, but be aware that plastics in general are much more thermally reactive to temperature changes than wood...particularly plywood. If you have wide temperature swings in your shop, plastics including hdpe will move a lot!

\http://www.engineeringtoolbox.com/li...ents-d_95.html

[Burkhardt]

I really like Garolite XX or Garolite LE (a.k.a Bakelite) for durable fixtures and mechanical parts. Much easier to machine than aluminum and less flexible, humidity and temperature dependent than simple plastics or wood. The glass-epoxy Garolite G10 is also great but nasty to machine with the glass fibers. McMaster has all that.

[scottp55]

I got a lot of recommendations to go Phenolic when I was first looking at repeatable jigs?

[EricSchimel]

Hey all, I got this all worked out:

Normally when I make jigs like this they are one time use... So I'll just mill them on scrap, use them right away and then toss them. In that context things like this work great. Like I said earlier I need to chamfer/break the edges of hundreds of parts over and over. I did get this jig to work (after I fixed my file) but like a lot of you pointed it out... It will wear out/move over time.

I ended up going to stupid simple route:

https://www.amazon.com/SHAVIV-29249-.../dp/B003JY7LXI

These little guys perfectly debur/break the edges and are faster than using the machine. So now what I do is chamfer one size and then cut the part off, and while I'm running the next batch I debur. Simple, effective and reliable.

[scottp55]

KISS principle

[EricSchimel]

Definitely! I was really skeptical about the de-burring tool. They're pretty great and indispensable if you're cutting plastic like this.