Corian remelt with V tool -- problem solved

[rweatherly]

I have been trying to use a V shape tool for lithopanes, and have had on and off problems with remelt that was sometimes difficult to clean up. I found that I could rotate the bit in the collet, and turn the remelt on and off.

I measured the tool runout and found .005" TIR and (not surprising), the cleanest cut came when the cutting edge was on the outside of the runout.
What was happening at other positions was the tool was rubbing the material more and causing it to melt instead of being cut.

[ger21]

I've never seen corian melt before. You must have gotten it really hot.

[rweatherly]

Corian uses an acrylic resin as a binder, and it can melt. There are several comments on the Vectric site about problems where the Corian does not look clean after you finish with a V shaped tool. Most of the time you break the particles away with a brush.

[ger21]

I've never carved it, but I've routed hundreds of sheets, and have never seen anything close to melting

[ckirchen]

Ditto to what ger21 said. What kind of speeds and feeds are you running?

My customer switched to Karadon from Corian a little while back and that does melt sometimes when Corian does not. It still comes out satisfactory, so i haven't changed the machining parameters.

[rweatherly]

30,000 RPM and 15 in/minute. I use the same speeds and feeds with a ball nose end mill and it does not produce the remelt -- I imagine that's similar to what you get with a router: the bit has plenty of chip clearance behind the cutting edge.

The problem only occurs when I use a V shaped engraving tool, and it is rotated so that the cutting edge is not at the outside of the runout.

There are some similar comments in this thread:

http://vectric.com/forum/viewtopic.p...d50ea6fea6f632

[ger21]

30,000 RPM and 15 in/minute.

Maybe that's why. I'm used to cutting at 250ipm and 15000rpm.

[ckirchen]

I'm running 5000 rpm (max for the machine) at 150 ipm. How come you're only going 15 ipm? My cutter is doing .0075" fpt, you're at .0005" fpt; can't the cutter handle more? Depending on the size of the part, you could save a lot of time.

Good job on finding the source of the remelt.

[rweatherly]

I am cutting lithopane, which is a 3D profile on a 3" square part. The cutting tool is either a .032" ball nose mill or a .125" V bit with a .010" flat on the end. I could go faster, but I have found that higher feeds do not produce the very smooth finish I get now.