Surfacing bit recommendation

Does anyone have a recommendation of what surfacing bit to use in the CNC?
I am now working on ‘cookies’ for clocks, with epoxy inlay and looking for appropriate surfacing bits for cleaning up after epoxy pour.
Thanks for any insight.


What size CNC are you using, is it using a trim router or a spindle. If you have a spindle that can take a 1/2" shank bit the Amana Bit RC-2255 is a monster surfacing bit. It is the one Shane uses for his Epoxy work (if you remember Shane Peters from the Multi-Color Epoxy session we have a few months back). I have also used this bit, but find with my machine that if not careful I can burn the wood, if I stop at all I will need to clean burn marks. I think the difference between Shane and my efforts is his machine has the ability to have a feed rate much higher than mine, so his bit is moving fast enough to avoid burning.

The other one I have used a couple times that worked OK is the Amana Tool 45525. it is a 1/4" shank, covers a diameter of 1.125" and doesn’t seem to have the tendency to burn like the bigger bit, at least in my use so far.

Do you have the technique for how to approach the surfacing solidified? If not we can discuss what Shane has taught me. Let me know.

Hope this helps. Good luck…Rob

Thanks for the great tip, Rob.
I would be using the trim router on the shop CNC to ‘lightly’ trim off the excess resin from an epoxy pour, essentially surfacing the face.

I have the RC-2251 and yes it is a monster! I bought the DLC knives for surfacing hardwood but actually had to take the bottom knives off as they got gunked up and started to burn. It did fine with just the two side knives though and cuts SO clean! They actually mention in the fine print to remove the bottom knives with hardwood.

Rob, Would like to hear your surfacing strategy! Can always learn new ways of doing things!

Paul, You are limited with the 1/4 shank. I’ve been successful surfacing with a 1/4 end mill but you have to tweak your stepover and be patient as it does take a long time. All of my surfacing bits are 1/2 inch or I’d lend you one. Be careful though. If you cookie is like mine it is turning into a bowl and I’m fearful of how deep you would have to cut to surface it properly. I made all of the text and features .125 deep but that might not be enough to offset the bowl effect.

I’m just going to go after the clock face with the sander. 80 grit till I get the epoxy cleaned off and then finer to finish.

Hope this helps!


Perry…i didn’t read any small print. Maybe there is a clue in there to why my RC2255 wants to burn my hardwoods. I was wondering since I used it on surfacing my mdf spoiler board a couple times, if the lades got a little dull and if I shouldn’t rotate them to essentially put on new sharp blades and then try again.

I haven’t surfaced anything other than spoiler boards, serving trays and cutting boards (when pouring epoxy). BTW…just sorta kinda retired. I would love to come down and look at your shop/CNC setup and swap stories. I would especially like to get some insights from you on the joinery and your setup. Enjoyed your presentation back awhile ago and was going to follow-up but got wrapped up with work.

Would you be open to a visit? If so, my email is Drop me a line and we can swap phone numbers and set something up in the next couple weeks. So many smart people in this association, I feel like a sponge sometimes trying to soak up information.