I am making my first tray with a 3/4" bowl bit from whiteside (1372) and my workpiece keeps getting mangled. The bit will take too big of a bite and move my board. Or it will not stay within the vector lines. I installed the tool in Vcarve pro using the .tool file from Whiteside and played with the feeds and speeds a bit but no luck. Is anyone else using the same bit? If so, any pointers?
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Lol I used the .tool file. Do you have this bit? Have you used it successfully on the onefinity?
Feed rate 80-120 IPM at .1-.15 DOC up to 50% stepover
PS if you are less than .24 step over you wont get the ridges at the bottom.
Set the makita router to 2.5
These are rough numbers but should work
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I’ll try this out. Thanks
Your doc is too much for that bit. I am assuming this is 1/4 shank so max doc should be .25.
I would run 23% stepover for that size bit. Generally the larger the bit the more scalping shows so running lower or less stepover percentages decreases the length of these scalping marks. With small bits you want more stepover do to the smaller scalping impact.
I also believe you may be pushing the bit as your feed rates are low. At 16000rpm I would increase feed rate to 200ipm and plunge to 100ipm. Doc .20 23%stepover.
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I have a 1" rocker bit which is similar. I’ve done 0.2 DOC, 80ipm, 14-16K, and ~75% step over without a problem. YMMV.
-Tom
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I ended up doing some tests for myself. This is .125doc and 3.5 on the makita router. going from 40ipm-200ipm. Raster area clears in 3" circles. Certainly not the most comprehensive test out there- but showed me that I can go 200ipm for what I need on my CNC.
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Great video. If you could take the cut shavings from each cut and compare them you would see where the differences in speeds is creating larger or smaller chips. Finding the largest chips would be the optimal speed between the different cuts. The chips you showed in the end looked really good.
I did a similar test with the same bit and found when you go to .25 doc and get over 250ipm the makita starts to struggle and is probably the max it will go.
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I fear your test is a bit flawed by the s curve acceleration. This was obvious in the fact that the circular motions were not getting much faster than previous runs however the straight slide move between each circle was faster. The acceleration model is great bit really skews tests like this. You almost need to record the screen during the largest diameter cut for each and see what speed it was running at and compare surface of each outer ring
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Great advice! I’ll make sure to do that on my next bit speed video!
Can you help? How can I open these files to look at?
Great test, thanks. This really helps!
Resurrecting this thread for a related question- how many “trays” are you guys getting out of a bowl bit? I want to say I got about 20 catch-all trays out of the last one I used, these were about 12x5" running 100IPM at about 2.5 on the router. Most of these trays were hardwood (cherry, walnut, oak). Can these be re-sharpened?
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i would use a clearance bit (CHEAP) before using a bowl bit (expensive) and just run a single pass with my bowl bit after using the much much cheaper clearance bit. you will probably get a whole lot more bowls for your money.
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