Tooling for Machining Richlite

Advice on CNC tooling that can cope with Richlite, a paper-based fiber composite material. January 21, 2010

Does anyone have advice for cutting Richlite sheets 1/2 and 5/16 thick? What kind of bit (diamond?), feeds, speed and overall mess? I will contact my bit supplier for their input also. The customer wants about 100 sheets a month.

Forum Resposnes
(CNC Forum)
From contributor K:
Richlite is another Corian-like material? I do Corian-likes all the time - solid VHM or inserts.

From contributor M:
I've done small quantities, 1 or 2 sheets with solid carbide, and it was okay, but diamond would work better on Richlite, and some of the other laminated papers like Fundermax, etc.

From contributor J:
I just finished a large reception counter of Richlite cut on my CNC. You don't need diamond tooling. I used 3/8" two flute combo spirals, cut 1.5" material in 5 passes.

From contributor A:
I've cut some 1" material before for counters with standard 2 flute solid carbide with no problem but at 100 sheets per month, I'd look at other options too.

From contributor S:
Wow! Richlite 1/2" material is $400.00 a sheet with freight figured into price. Your 100 sheets a month would be $40,000 a month in your material cost. You are one lucky dude to find a customer like that.

Please note that they do not make a 5/16 thickness. I am a Richlite fabricator and at times have had to cut 40 sheets a month. The dust from this material grinds everything it gets into. Carbide bits last about 15 sheets before they start to rub, not cut. Use an air vortex to cool the bit. An 8 hp spindle is minimum size needed to continuously cut this material. Do not let dust get into your ball screws or you will wish you didn't start the project.

From contributor B:
I've never run into this product with a customer. It sounds like an interesting challenge (and I'm always up for an interesting challenge). My gut feel is that solid carbide spirals will only be good for short-term production. If your supplier offers a "high wear" version, that would be the starting point. Diamond would be the way to go, long term. From a performance standpoint, I would expect that the tool would require a lot of shear to give a good finish, top and bottom. Paper laminated particleboard requires about 30 degrees. I would expect Richlite would, too. That causes a problem, from a tooling standpoint. When it comes to tipped tools, the greater the shear, the larger the required diameter. The larger the required diameter, the greater the required horsepower. The smallest diameter standard tool available from my suppliers is 18mm.

From contributor I:
I am surprised that none of the above mentioned the smell! Unless they have changed their formula since I cut some a while back, it smells horrendous but is excellent material. Make sure your chip load is correct to help keep the bit running as efficiently as possible. A cool air gun is also a good add-on to extend the life of your bits. I would also recommend a DBSU (Diamond Bit Single Use).

Keeping the bit cool is crucial to its life cycle and if it gets too hot, the braze will let go on some of the cheaper brands. I have tried most of the PCDs out there and most of them are not made to cut more than 300IPM. We have used one brand for over a decade that has consistently stood up to our 750+IPM use on MDF core 2 sided melamine and averaged 250 to 300 sheets per bit and we have also achieved over 500 sheets on one occasion with this same brand.

You did not indicate what kind of CNC you have or what HP/KW your spindle is. As someone above mentioned, this will be crucial also. Did I mention that it smells nasty?!

P.S. There are several types of Richlite and the others may not smell as bad as the 1.5" industrial, but be prepared.

From the original questioner:
We have an Onsrud CNC with a 16 horse motor. I'm starting to think that this Richlite stuff is something we should avoid. I don't think the money to be made justifies the mess and machine wear and tear. Thanks for all the responses.