Multiple Finish Passes

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Rcnewcomb
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Multiple Finish Passes

Post by Rcnewcomb »

We recently have been experimenting with doing two finish passes. The second pass is done with the same bit as the first pass but rotated by 45 degrees. This seems to improve detail considerably.

I'd be interested in hearing from others if this two pass technique works as well or better that going to a smaller bit.

Background:
Our shop computer has limited memory so we have been looking for methods around the "Out of Memory" errors we received when we would try to toolpath with a 1/8" ballnose. We have been using a 1/4" ballnose with generally good results, but on some designs we were looking for finer detail. The two pass method with a larger bit gets around the Out-of-Memory issue and gives us the option of taking a second finish pass if the piece would benefit from it. For example, a design cut in cherry might benefit from a second pass whereas the same design cut in red oak might not.

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Paco
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Post by Paco »

Calculate the two finishing pass separately.

Since time is money (in my case) I prefer to sand some instead of running the tool for several hours to save 1/2 hour of labor. The late generally being done WHILE the tool work...
In fact, I have seen very much improvement from more than one finishing pass. What I found to make the sanding easier is to cross grain machine instead of along the grain, in solid woods that is. Conventional cut is better than climb when your CAM allow this kind of setting. Other material react differently; HDU being my preferred! :wink:

RAM isn't very expensive if it can get you more work done... faster. Think of it as investment.

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