Noooo! What’s the fun when we already have lost?? 
Interesting that the variations are similar. I wonder if you get the same numbers if you go slow?
I also think I’m going to stick a piece of gorilla tape to the extended dust hole on the bottom of the plate. Still shooting a stream of crap off to the side. Didn’t cover my laptop this time though.
I’ll try a slow pass next, just for giggles.
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Nope…there is always room to squeak ahead by a second. Or more accurately.
12.55…get that to 12 and stop cutting that extra 1/2 a mm! (dang 2:30, that is gunna be a tough number to match and then beat)
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From 16min all the way down to 2:30 so far. If this gets much lower we will need to run a two cut job to measure the actual differences.
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Okay, slowing down to 6mm/s
99.07mm
12.27mm
Cut time was about 4:30.
Also, I need to put on a heavier shirt. It’s only 54f outside today, and running an open flame heater when cutting mdf is a bad idea…
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Oh yeah… it’s on! hehe
I am looking forward to filling my bucket with dust today. When I get back from my son’s baseball game, I am going to put down my new resin printer, clamp down some mdf, strap on a 1/4 up cut, and head to the starting gates.
BTW, will 1/4 cut the min radius? If not there may be a pit stop involved for me. Would be fun to add tool changes to the mix hehe.
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You’re good!
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Just curious why you slowed it down when you were already under 3min?
I have my spit ball shined up for y’all when I get back ;). I have a 2min CAM file that is a bit conservative for my machine with mdf… fingers crossed.
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Turbinbjorn was wondering if my measurements would change if I went slower. Didn’t really make much of a difference.
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I think we need to cut out a part to give the 1/8" a fighting chance.
Haha - this is embarassing! I couldn’t help get riled up by Barry. 12mm DOC, 10mm/s. 2min10sec. The measurements are all over the place, and it was skipping and jumping. I’m suprised nothing caugth fire! 
I guess I should try two passes next time…
Edit: 6mm single flute endmill. It’s all blackened from before. It was supposed to be blue. Has the hardening gone out?
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Here is my first attempt at an entry in the CNC Logo Cutting Race!
First the good news: Just over one minute with my Portable Primo:
I only have 12.5mm MDF on hand, so I made some practices with 18mm plywood and it worked very well:
But when I did my 12mm cut in 12.5 mm MDF, it turns out that 0.5mm of MDF was not enough to keep the center of the logo anchored down and it flew out, and I aborted the run. The timer photo is from an air cut right after that.
Here is the video, of the MDF attempt:
https://photos.app.goo.gl/iMNjih3kc5oiPVhP7
and here is the video of my cutting plywood first, which went well:
https://photos.app.goo.gl/ZXx3PpBWz6FDuxPF8
Here are some measurements:
I used a 6mm 3-flute upcut endmill with good plunging ability. With my 1.5kW spindle it has no trouble cutting 12mm in one pass at 30 mm/sec. It does make a hell of a noise and a lot of dust!
I spent some time optimizing the toolpaths (all Profiles) in VcarvePro, and saved all toolpaths as one gcode file, which further optimizes the rapids.
I will try again when I get some thicker MDF.
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Nice! Impressive. Would you mind sharing where you got the endmill?
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Just a FYI, mine are from carbide3d on ebay. I think all my 1/8" endmills are from the shop here now.
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I got this endmill from Caulfield Industrial in Galway (here in Ireland). They are great. I believe it is German (Guhring?) but not sure because it was not what I ordered (I ordered a ball-nose) so they let me keep the endmill for free and sent me the ball nose. It is solid carbide.
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We can change the rules so you don’t have to pocket the part you can just cut inside and outside edges.
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Here is what my profiles look like. The three arc profiles that do the clearing only added about 22 seconds to the whole thing. You can see if you look carefully, I added a finishing pass to the outer profile, which took the total time from 52 sec to 1 minute 4 sec.
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Yikes! I forgot to enable arcs after a firmware update. Thanks for the reminder
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@stevempotter Heck yeah! That squealing and slight smoking is what I like to see!
Manually assembling profiles is pretty clever too. I’m wondering if you cut starting from the island and working your way outward, perhaps the inside piece wouldn’t break free.
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Thanks, Jamie. I always use tabs that are at least a mm or two thick for things that might break free, if it is a carving I care about. Your idea might work, but tabs are a better solution. Or just don’t cut so close to the bottom of MDF stock!
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