Burning when surfacing maple

it was likely the mdf that dulled your bit, if anything imho. you may slow the rpms down to 10k or so and try it, since that is a 3 flute. burning means cutter is dull or spinning "too fast", or feed rate is too slow. since you can't feed faster, you have to slow down the rpm's.

Do you mean inches per minute? 100 inches per second is flying. What is your machine? The pic looks like you may have a tramming issue, too. Does the material have ridges or is it just that the burning makes it look that way in the pic?

I agree that you may have a tramming issue. I use a two-flute flat bottom bit to surface my spoilboard at 400ipm (18k rpm). Something like the Maple you've shown I would probably surface at 200ipm to 250ipm.

Thanks for your replies. I did try slowing the rpm down to 10K at which point the router was stalling, but no difference. Yes, of course I meant inches per minute! The system was tramming previously, but I fixed that and the surface is now completely smooth to the touch - the main scorch marks are on the point where the bit is making the cut. As it surfaces perfectly with a 1/2 inch router bit I am inclined to think that the Amana bit has dulled, which for an expensive bit is disappointing, after just 4 uses. My Machine is an Oozenest WorkBee. Max speed is 2500 mm/min, which equates to 98 ipm, so I am thinking that this is just the wrong bit to use with this machine, however running at 15000 rpm and 98 ipm would give the same chipload to that recommended.

fwiw the chip load calculator i use from US Router Tools suggests 855-945 ipm at 15k rpm's, 3 flute on hardwoods (0.02 chip load)
you may also try a lighter cut at a lower rpm...

if you have tried all of the recommendations and still burning, your bit is likely dull...

MDF and even plywood can dull router bits faster than most hardwoods will. True for jointer blades as well.
4D