Rough Profile Cut

Hey everyone I am new to CNC and have been enjoying the process so far. I am thinking this is a speeds and feeds thing and maybe tool choice as well but I was wondering if someone could point me in the right direction. I’m using the Jenny 1/4in bit from Cadence Manufacturing for my profile cuts. This cut was run at 75ipm at a 3 on the makita router. I did mess with router speeds while it was running and I was unable to stop the chatter. I am cutting white oak, walnut, and purple heart. My profile cuts come out with visible marks from what I assume is bit chatter. You can also see each depth of cut (set to .25 right now) on the projects and this requires an enormous amount of sanding to get out. I want to run as fast as I can while also getting clean re I would love some help and look forward to fixing the problem and hopefully getting some smoother cuts in the future. Thank you!

Chatter can come from the part not being real secure to the spoil board as well, I use Vectric and it allows for a final pass on the profile which can eliminate the chatter as well

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I use Vcarve Pro I’ll have to give the final pass a try. As far as projects being secure I’ve used a nail gun in all 4 corners as well as the painters tape and glue technique.

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It matters if it is up or down cut Jenny, but I would think depth of .25 is a little deep except with compression bits. Usually depth of cut is 50% of tool diameter, and if you did shallow it up to .125, I think you could increase the 75ipm to perhaps 100 or 125 without chatter. It’s worth a try as hardwoods can be very demanding for a trim router.

I also recommend at least 16,000 rpm for the Makita, or perhaps a bit more (don’t know the settings, but it’s on this board somewhere)

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I appreciate the advice I’m using the Jenny Compression Bit PN 8675309-J. I will Try adjusting the Depth of Cut and see if that fixes my issue.

Also make sure your bit is set to the right depth in the collet. You may have too much of it out and that’s allowing for some chatter. Another possibility is your Z-axis and how you have your slider mounted. You have 3 positions and I think Onefinity suggests the middle one. If you are using the top one you might have more opportunity for chatter there too.

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I have my Z axis set to the lowest (closest to the bed setting) I will also watch videos tonight or tomorrow and make sure my bits are inserted correctly. Thanks for the input!

I also think .25 doc is a bit agressive for the Makita. On hard woods I stay at .1 doc, and 80IPM (sometimes even slower if it starts to scream) with the Makita at 2.5. Also, use a seperate last pass, I use .03" and have good results.

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Hello All,

I am doing my first cut on white oak as well. My project board is 30" x10" x 1". I am making a serving tray for my daughter in law and she wants it 3/4" deep large pocket toolpath. I have two 1/4" 2 flute bits one is up cut and the other down cut. Any recommendations on speeds and feeds and which bit I should use? I have plenty of experience on softer woods and this stuff is dense!