Draw the jig or the cut?

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hobgobbln
Posts: 266
Joined: Tue Apr 13, 2010 7:31 pm
Location: Palmer, Ma

Re: Draw the jig or the cut?

Post by hobgobbln »

Thanks for the help so far everyone. I say so far because once I get the machine converted over to CNC you'll be seeing me post again.

Frequently :lol:

Griz
hwboivin3

Re: Draw the jig or the cut?

Post by hwboivin3 »

Thread milling is essentially the same program. You would modify the depth per pass to match the pitch and adjust you radius to size for a nice fit.

As far as distance over the jaws ,.... I prefer a minimum 1/8 deep into the soft jaw for the fixture, and if possible I like to make them 1/2 deep.


Harry


p.s. what kind of mill are you converting ?
hobgobbln
Posts: 266
Joined: Tue Apr 13, 2010 7:31 pm
Location: Palmer, Ma

Re: Draw the jig or the cut?

Post by hobgobbln »

hwboivin3 wrote: I prefer a minimum 1/8 deep into the soft jaw for the fixture, and if possible I like to make them 1/2 deep.
The rough blanks are 0.187-ish thick. My finished thickness is 0.140". That sounds like a lot of material to remove but it allows for angular error with the saw cuts. I know that if I had my band saw tuned up better I could waste less material but I get over 400 of these from an 8' bar so I'd rather stay on the safe side. Someone else is going to be cutting the blanks for me and I'm sure his saw cuts straighter than mine but I still plan on being over sized. Besides, I have to machine every surface anyway so as long as I can get the faces parallel, making the rest concentric and perpendicular will not be a problem.
hwboivin3 wrote: p.s. what kind of mill are you converting ?
It's a Grizzly X3 benchtop. I've had it for a year or two and its been a much better mill than the tiny X2 I started with. I realized after I picked up my lathe that I really don't like milling. I don't mind running my little lathe for hours on end but I cringe when I have to mill something. In all fairness though, I have never run a full sized mill. I have no doubt a more rigid and capable machine would be a whole different story but limited space has kept me from buying one. That's why I figured I would convert it to CNC. Its sitting there anyway, I may as well get some use out of it since it has been more than adequate for what I have done so far.

Same with my little X2. I ended up getting a lemon but didn't know it at the time because that was my first machine. I wouldn't waste my time using it for a drill press right now. I have seen some amazing work done by other people with theirs and after spending many hours chasing issues and reading tips on improvements for it, I have no doubt I got one of the bad ones. Once I get caught up with the job I'm running I will go back to tweaking it and getting it usable.

The most amazing machine in the world can't compensate for an unskilled operator but at the same time the most skilled couldn't make parts for NASA with a chainsaw and yardstick. Unless your building them a crooked fence :lol:

Griz
hwboivin3

Re: Draw the jig or the cut?

Post by hwboivin3 »

Approx .040 to mill off a saw cut part is nothing. I usually leave twice that but my saw is not the greatest.

I guess for a piece to finish at .140 thick, I'd try for a 1/8 deep pocket.



Harry


I love running mills...... I cringe at running a lathe!
:(
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