New user... having trouble getting a real clean cut on fonts

Discussion specifically about the Shark's bigger brother, the CNC Shark Pro

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jeb2cav
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Re: New user... having trouble getting a real clean cut on f

Post by jeb2cav »

Hi Lauren,

One thing I'd check is how much of the bit you have chucked into the router. I was working with a fellow the other day and in the end, the majority of his 'problem' was the result of not ensuring a reasonable amount of the shank was in the collet. As soon as he corrected this, the majority of his problems went away.

Are you using a Colt router? I have seen articles and posts where the TIR (roundout) of the spindle itself can vary quite a bit, and you may have a lemon in this regard. I have myself ended up with one of those (I've purchased 3 since starting). In that case, I had purchased the extended warranty from the big box store and took it back for exchange. I also invested in the precise bits collets for my use, and these do help this as well.

Assuming the cutter is in good shape (obliged to say it).

Your settings seem fine - but you don't mention an ipm feed rate or plunge rate. You can definitely try lowering both to see if that gets you what you want. I've found that a slower plunge rate can improve things for me, particularly in hard woods. Certainly there is a knee in the curve for the ipm as well, but generally with lettering the gantry never gets close to the ipm you've set - too much movement.

"What does that do" - is best explained in the VCarve manual - in VCarve, Help, Help Contents - this will open the manual in pdf form. Do a search for 'final pass stepover'.

Lastly, the font you are using could be contributing to this. If there are a lot of unnecessary vertices in the font, the Shark my be trying to get as close as possible to them and this movement is slight, but enough to contribute to this. You can get a sense of this by using the 'Convert Text to Curves' tool, and then selecting a problem letter and going into the node edit mode to see. There are some settings you can change in the tap file, but I'll hold off on that for now until you think about the above and let us know if any of it helps.

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lauren
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Re: New user... having trouble getting a real clean cut on f

Post by lauren »

Hi Joe

Thanks for the info, my plunge rate is 30 and ipm is 60. My v-bit sticks out about 1/2" maybe a little more out of the collet.Oh by the way it is a colt router and i have it set to max.
I'll try running the program again and see if things change.

Again, thanks for the reply.

Lauren

tonydude
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Re: New user... having trouble getting a real clean cut on f

Post by tonydude »

Hi Lauren,

You might try slowing down your rpms on your router to # 1 or #2 on the dial, it might help.

Tony
Buffalo,NY

"What will matter is not what you bought but what you built; not what you got, but what you gave”

Aspire 11.015, photo vcarve, cnc mako shark extended bed with the new upgraded HD 5 gantry with Led pendent.

saramos
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Re: New user... having trouble getting a real clean cut on f

Post by saramos »

I second the idea of reducing your RPM. If the RPM is too high, you are more polishing the wood than cutting. It will also dull the bit much faster. If your cuttings are fine dust, it's definately too high. You should have more of a granular dust.

Scott

jeb2cav
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Re: New user... having trouble getting a real clean cut on f

Post by jeb2cav »

Those are great points as well. Getting back to the shaft - from reading around the 'more' shaft in the collet, the more stable the cut. Frankly I hadn't thought about this much before, but in looking at the 'sign kit' bits I purchased originally from rockler, I've chosen to place them up in the collet with about less than 1/4" space between the collet and the top of the cutter (like the V60D bit). Vbits I've purchased elsewhere since then that are intended for CNC work do have a longer shaft.

Again though, also, please keep in mind that in fact you may have somewhat of a lemon for a Colt. A really good post on this, how to check it, and how to finesse it yourself is http://www.cncsharktalk.com/viewtopic.php?f=9&t=785.

Keep us posted - good to know what works for folks.

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lauren
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Re: New user... having trouble getting a real clean cut on f

Post by lauren »

Hey guys,thanks again for info will run program and let u know.Its great that there is help out there.

Much appreciated
Lauren

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