Cleaning up machined sides

[Ohio]

Okay, well, I've done two carvings, one from a logo that was a single-sided and one from a spoon pattern that was a two-sided carve. It was pretty neat.

I'm still mastering the basic concepts but I did wonder if I could get some pointers regarding getting a cleaner machined edge. I mean, I am good at sanding based on many years of screwing up woodworking projects, but it isn't something I find fun. So I have a 1/16 carving bit and a 1/8 cutting bit and have used only the 1/16 carving bit on my two projects.

What are the basic steps to check to get the best finish off the machine?

Thanks, you all.

[fwharris]

For the best carving quality it usually recommended that you set the bit optimization to best and during the upload to the card us the optimal setting. Also using harder wood types will give you better detail with out the fuzzies.

[Ohio]

Ok, thx, I used some western red cedar for the logo one-sided carve (I figured it would chip out and it did, but still...) and I used kiln-dried cherry for my double-sided carve. I set bit optimization to Best and I thought I used Optimal at the machine, but maybe I didn't. I'll double-check next time.

Any other tips to get a better finish off the machine?

[DickB]

For the best carving quality it usually recommended that you set the bit optimization to bestI don't agree with this. It really depends upon what you are carving. Bit optimization affects the shape in a small way of what is being carved, but not the smoothness or what I consider to be the quality. I posted on this subject here: http://forum.carvewright.com/showthread.php?22299-Trouble-with-text&p=194177#post194177

[fwharris]

I don't agree with this. It really depends upon what you are carving. Bit optimization affects the shape in a small way of what is being carved, but not the smoothness or what I consider to be the quality. I posted on this subject here: http://forum.carvewright.com/showthread.php?22299-Trouble-with-text&p=194177#post194177

Hence the work "usually" ;) It is a lot dependent on the quality of the pattern for the most part. It does bring out the detail and or the defects in the pattern.

Maybe he should post a picture of his carving so we might get a better idea of what he is talking about for the edges.

[SteveNelson46]

Bit optimization is the procedure used by the software to compensate for the taper of the bit. The "Best" setting does not always produce the best quality. Especially with some fonts.

With raster carves the over all quality of the carving is set by adjusting the "step over" of the bit. In other words, how far does the bit overlap the previous pass. It's usually measured in percentages but with the Designer it's measured in pre-set steps of Draft, Normal, Best, and Optimal. These settings can be selected when the project is uploaded to the card.

[bergerud]

Bit optimization is the procedure used by the software to compensate for the taper of the bit.

Bit optimization is not to compensated for the taper of the bit, it is to compensate for the fact that the tip of the bit is a ball and not a point. Without bit optimization, the machine carves by having the tip (point) if the bit follow the pattern. Since the ball is not a point, nearby parts of the pattern may be carved away by the sides of the ball. Bit optimization calculates how much to raise the bit as it carves so that the sides do not cut into the nearby pattern.

It is easy to think that bit optimization has to do with the taper since the rise in the bit also reduces the amount cut by the taper. But that is a side effect. (pun intended!)

There is no way to compensate for the taper of the bit. All one can do is apply small draft, so that at least, one can see what will carve.

[SteveNelson46]

I stand corrected.

[Ohio]

Thanks all.

I think I'm starting to get a grip on this. The model I used was a spoon MPC from the free patterns collection. I removed some of the design elements and made it smaller. I wanted to do 1) a double-sided carve) and 2) something simple in a wood I'm familiar with to see the result. I had a KD cherry short that I ran through the planer to get about .80 (a little thicker than the design) and plenty of extra all the way around (too much---I need to build a sled). It took about 58 minutes for both sides, the DC worked great, the carve came out nicely.

I've already sanded the spoon down and oiled it---I ran out of my usual beeswax/mineral oil food-safe finish. It's already in the kitchen and in use.

I read DickB's linked thread and will continue reading up on this. I need to get into my head that the use of "Optimize" and "Optimal" within the software and hardware, and the relationship between those two. I have some other KD hardwood that isn't as precious as the cherry and I can run the same pattern using different settings that may help me understand that part. I think the only way to really understand it is to do carve a lot, keep reading, and take copious notes.

Oh, and I'm a she. Not a he. At least, the last time I looked.

[normrichards]

Congrats, a two sided carve is ambitious for first couple of carves , I probably did not attempt until my 15th.

[DickB]

I need to get into my head that the use of "Optimize" and "Optimal" within the software and hardware, and the relationship between those two. I have some other KD hardwood that isn't as precious as the cherry and I can run the same pattern using different settings that may help me understand that part. I think the only way to really understand it is to do carve a lot, keep reading, and take copious notes.You can generally see what the Bit Optimization setting will do in Designer, before you actually carve. The attached images are of one of the built-in patterns, Basic - Composition - Crest 01. The first is with Bit Optimization: None and the second Bit Optimization: Best. Because this pattern has some fine detail and is fairly deep, you can see a significant difference - look closely at the center of the pattern, and at the upper edge, as you toggle back and forth. With other patterns that have less detail, such as Basic - C Fillagrees - C Filagree 01, you will not see much difference.

83136 83137

[Ohio]

DickB, thanks for the examples. I did that on the spoon pattern I ran on the KD cherry. I saw very little stair-stepping in the software but had quite a bit on the piece. I think I may have mismatched what I told the software the bit was going to be, so I'll double-check that.

Thanks all.