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James Jaragosky
04-11-2009, 7:33 PM
3 Bits in three days. All because I have a loose nut behind the keyboard.:rolleyes:

Keith Outten
04-11-2009, 9:48 PM
James,

Is it the bits or your mistake?

Awhile back I orderd a bit that Onsrud told me was the best router bit for Corian. It didn't last very long before it broke. The common Whiteside spiral bits I had been using were lasting for months and they aren't recommended for plastic. In spite of what the Pro's say I am going to stick with what works :)
.

James Jaragosky
04-11-2009, 10:15 PM
James,

Is it the bits or your mistake?

Awhile back I orderd a bit that Onsrud told me was the best router bit for Corian. It didn't last very long before it broke. The common Whiteside spiral bits I had been using were lasting for months and they aren't recommended for plastic. In spite of what the Pro's say I am going to stick with what works :)
.
Thanks for the advice Keith.
I broke two pushing the limits of the bit for its size and one I broke with shear carelessness.
I have been using American, and Onsrud with good success so far; I also picked up the think and tinker collets; and I am very happy with them.
Thinks are going better now that I have the loose nut behind the key board under temporary control.

Skip Weiser
04-13-2009, 2:58 PM
3 Bits in three days. All because I have a loose nut behind the keyboard.:rolleyes:

It's just part of the learning curve Jim, and we learn from our mistakes and try not to make the same one twice.

Regarding the Think & Tinker collets you mentioned above, yes those are awesome. I got mine about a month ago. I cut alot of small parts for a knife manufacturer out of thin 16" x 32" Dymondwood panels.

The parts have a + 0.000 -0.007 tolerance on the OAL. I use 1/8" coated end mills and had been using a 1/4" PC collet with a 1/4 to 1/8 reducer bushing. I always check how true the bit is turning with a dial indicator before I start. It would sometimes take forever to get the bit turning true. Tighten it up, check it, swear, loosen it, turn the bushing a little, tighten, check, swear again, etc. etc.

I popped the 1/8" T&T collet in, tightened the nut, checked the bit with the indicator and it ran out less than .001. YAHOOOO !!!

If I wasn't trying to maintain close tolerances, a little bit runout wouldn't be so critical, but the company gives me a .007 tolerance and I give myself a .005 tol. and shoot for .004 or better, so the bit needs to run true or the sizes are off.

And it was here on SMC that I first heard of precisebits.com and their T&T collets for Porter Cable routers, so thank you guys for posting about them!

Carl Vastola
09-30-2009, 10:50 AM
I have a formula for feed and speed that works well. For 7.5hp spindle. Bit diameter x 600. If you have a .250 bit times that by 600 and you get 150 ipm
Lets say you have a 5hp spindle you would use hp times 80 = 400 so you take bit diameter x 400. that's .250 x 400 and you get 100 ipm.

I have used this for years and works well. It's a good start point.

Khalid Khattak
09-30-2009, 11:40 AM
"Darn It".. what does it means?... I am a learner please don't offense..

Guy Mathews
09-30-2009, 12:06 PM
"Darn It".. what does it means?... I am a learner please don't offense..

Khalid,

Think of it as making a mistake and instead of using a word that would offend just about anyone that hears it, you would say "Darn it!" instead.

It is an appropriate way of expressing being dissatisfied or not liking something that you did that has happened.

By the way, the mirror you made is beautiful!

Carl, I love the formula trick. Will have to remember that one as I am dealing with a 5hp on one machine, a 10hp on another, and 15hp spindles on my 10 Spindle CNC Carving Machine.
Guy