What's this Carbide coating.

[charlieuk]

Unfortunately not I'm looking for exactly the same as my picture just with the cutting depth to be about 3 inches rather than 1.5

[IanS1]

This seems to be the manufacturer http://www.saburr-tooth.com/index.htm can't seem to find any info on longer shanks on their site though. Do you need the whole burr to be 3 inches or just the shank? If you're happy with a longer shank perhaps you can have an adapter made, to give the effect of a longer shank, to fit your spindle

[charlieuk]

Yes those are the ones I got, a longer shank would be a start but ideally the cutting edge wants to be longer . Many thanks

[Beone]

What you are looking for is called a rotary rasp.
Dave

[Boyan Silyavski]

Thats definetely non stick teflon coating, similar to Freud .

Now i i don't have something clear. Why use burs instead of some ultra sharp sharp micro grain carbide router bit, say 3 flute straight long reach?

I don't see how you will route faster with these compared to normal router bit. Also if you insist on burrr just buy roughing bits.

What size bit, depth of cut, speed and step over? lets do the calc here. cause i dont see it right using these bits on foam.

[njhussey]

there's these ones from France....http://www.hand-stitched-rasp-riffle...tre-25-mm.html

Or this, I know it's only a ball but it's 30mm diameter? http://www.clasohlson.com/uk/Rotary-Rasp/30-9512

[charlieuk]

The burr style is a prity standard practice when working on surfboards. From experience I have had in the past normal fluted bits can tend to heat up after a long duration and coolant is not a option and on eps this can end up melting the foam which can make a right mess. The burrs also give a great surface Finnish.

im open to ideas ?

I played with the two burrs I have today and even the fine one seams good.

No idea how hard or I fit would be posable but would it be posable to make a blank bit on a lathe and then coat it in some sort of abrasive grit? I'm assuming balancing would be the major problem?

[Boyan Silyavski]

i would give you tons of ideas but you have to give me some data to work with

What size burr, depth of cut, speed and step over you use now? Do you pocket or slot cut? What is your collet size ? Spindle kw and rpm? What speeds your machine is capable of? What rails and ballscrew ?