| Official Luthiers Forum! http://mowrystrings.luthiersforum.com/forum/ |
|
| Need to buy new bits for my cnc http://mowrystrings.luthiersforum.com/forum/viewtopic.php?f=10106&t=44534 |
Page 1 of 1 |
| Author: | RuelasGuitars [ Sun Nov 09, 2014 10:22 pm ] |
| Post subject: | Need to buy new bits for my cnc |
Hi I'm putting together my set up for the next phase in my cnc experience. I've only done inlay on my small cnc and have a larger one 24x30 on its way and was wondering if anyone could recommend sizes/lengths for cutting body's (I'm thinking 2" long?) Also what's a good bit to radius fingerboards and what's a good source to buy them from. Thanks this information is going to help me out big time. |
|
| Author: | PeteFede [ Thu Nov 13, 2014 8:42 pm ] |
| Post subject: | Re: Need to buy new bits for my cnc |
There are a few ways to go. For contouring bodies, a 2 inch flute is a must in my book. Carbide spiral bits work great. Down cutting bits will give you an exceptionally clean edge to pockets. Up cutting bits clear chips best. For pockets, I will run a down cutting bit 1/4" deep to establish the line and then finish the pocket with an upcut. Consider whether a compression bit would work for you doing body contours. It will upcut the bottom surface of your work and downcut the top surface. I have a few in hand but have not tried them yet. We use a 1" ball nose straight bit to radius fret boards. I have a 2 inch on my shopping list. In terms of diameter, bigger is better. Use the biggest bits you can for the radius in question... that's my suggestion. There are are variety of sources for bits. The usual woodworker supply stores usually offer Onsrud. You can also source excellent 30 degree helix 2 flute mills from metal working suppliers. Where I am, I deal a lot with my local HAAS factory outlet. I mostly use a lot of Garr carbide tooling. |
|
| Author: | Andy Birko [ Fri Nov 14, 2014 1:27 pm ] |
| Post subject: | Re: Need to buy new bits for my cnc |
PeteFede wrote: We use a 1" ball nose straight bit to radius fret boards. I have a 2 inch on my shopping list. In terms of diameter, bigger is better. Use the biggest bits you can for the radius in question... that's my suggestion. I agree but just be sure to check for compensation when using large bits as your CAM software may or may not do so. For a 2" radius bit radiusing a roughly 2.25" wide board with a 16" radius, the center of the tool has to be about 1/4" off the edge of the fretboard to accurately cut the radius. |
|
| Author: | PeteFede [ Tue Nov 18, 2014 9:52 am ] |
| Post subject: | Re: Need to buy new bits for my cnc |
Good point Andy. Larger ball mills may also need to cut deeper off waterfall/bullnose type edges so may cut up your sacrifice board &/or jig more than you expect. |
|
| Author: | Bob Garrish [ Tue Nov 18, 2014 7:42 pm ] |
| Post subject: | Re: Need to buy new bits for my cnc |
USA Carbide makes decent tools, and their prices can't be beat. Their carbide stuff is razor sharp, which is excellent for wood. If you don't have motion errors, you can get a very high quality finish with a sharp 1/2" ball on wood and a 0.010"-0.015" step-over. Use the biggest ball you can, but don't outstrip the rigidity of your machine chasing a finish you can get with more passes and a smaller cutter. Get the minimum amount of flute you can get away with on cutters, especially balls, and limit the stick-out on the cutters as much as possible. Reduced neck cutters are a blessing on mankind. You can get away with only using regular spiral cutters so long as you're careful on depth with the first couple passes of a pocket. You'll get 'fuzzies' on the edge, but not blowout, and they knock off with one swipe of 220. |
|
| Page 1 of 1 | All times are UTC - 5 hours |
| Powered by phpBB® Forum Software © phpBB Group http://www.phpbb.com/ |
|