Carving Corbels and Accessories

[patricktoomey]

I'm trying to do some V Carving and some carving with ball end mills in maple and I'm having some trouble. Because of the nature of maple, I'm ending up with a tremendous amount of fuzz in the carved end grain of the parts. The amount of handwork it would take to clean this up negates any savings over just buying these things from someone else. I've noticed that a lot of carvings are in basswood and I'm wondering if anyone else has carved basswood with a ball end mill or v carve bit? If basswood produces something that needs very little hand work, I can finish it to be a close enough match to my maple cabinets.

To date I've tried hard and soft maple of varying grades. I've used 60, 90 and 120' vcarve bits, ball end mills from 1/8" to 1/2" and 1/4" spiral upcutters with equally poor results. I've run the RPM's from definitely too low to definitely too high (looking at the chipload). The higher RPM's seem better but burn the wood in spots. I'm using a dust collector and in some cases even an air jet to clear the chips.

Does anyone have any suggestions?

Thanks in advance,

Patrick

[rcnewcomb]

Can you determine if the fuzz is due to material movement? Can you post any photos?

We have been having good luck v-carving hard maple. We do run into problems if the bits are dull or the feed rate is too high. We use vacuum or screws for securing our maple.

[mrdovey]

I've cut hard maple without problem when I used a really sharp bit. With a duller bit you get fuzz; and with a really dull bit you may actually see splintering and heavy tear-out.

I was running 1/2" 2-flute end-cutting straight bits at 18K RPM and about 1.5"/sec feed on x- and y-axis.

Make certain your bits are really sharp.

[hespj]

Morris, I see this gives a chipload of 0.0025 which is somewhat below the recommended 0.005-0.03. Doesn't this cause other problems?

This isn't a criticism, it's me trying to understand chipload. The recommended chipload range seems enormous, and yet I often see people are running outside this range quite happily.

[mrdovey]

With the maple, I haven't seen other problems - no overheating or premature dulling of bits, no no burned wood, etc. Cuts have varied from 1/2" to 1" deep.

[patricktoomey]

Thanks for the suggestions guys, I really apprciate it. It's starting to look like a combination of factors that may be biting me in the butt here.

Randall, I did another test and one of the problems with my up spiral bit does seem to be material movement, it seems to be pulling the board upwards and giving me some gouging.

Morris, I thing the really sharp bit and higher RPM's may be the key too. I was using bits that I have used for other work thinking they still "felt" sharp to me but that's a dangerous assumption apparently. I put a brand new V Bit in, clamped the heck out of a hard maple board and put my RPM's way up. I was looking at the same chipload calculations as John thinking that I shouldn't be up that high but it did cut MUCH better, only a little hand cleanup in a couple of spots. I think my burning issue with the higher RPM's was due to a dull bit. From now on I'll use only brand new bits for my hardwood carving jobs and then mark them for use in other materials that aren't so sensitive.

I'll post some before and after pictures here tomorrow for an example of what happens when you don't use the sharpest tool in the shed :-)