Cut inside letters when using a v-bit is not smooth!?!?

Hi,

I was carving the letter “C” using a 90degree v-bit. Once the bit had finished cutting i could see ‘steps’ inside the cut which almost look like the cut depth for each pass? Anyone experienced this before and know how to address it?

Thanks!

Hello Matthew,
I have had it happen to me before but like you said its the cut dept for each pass. What type of wood are you using? Are you using a good bit? I will attach a picture of some V Carving i did in mahogany. You can see that I have the dept of pass lines also.

It could be multiple things. What bit, specifically, are you using? The angle could be off.
That could also be caused by tool deflection, a router not square to your work or something mechanically loose.
My first guess would be the bit angle, though. Try a test at 58 degrees.

Hi Russel,

I’m using Hevea wood, which I have previously used and had no problems with. It is a good bit, I’ll link it below so you can share your opinion on it: https://robosavvy.com/store/carbide-v-bit-60-1-8-shank.html
Did you decrese the depth per pass to resolve?

1 Like

Hi Neil,
The bit I’m using is:

Ok, I didn’t think to check that. I’ll watch a video on what exactly I should be looking for when cutting 58degrees. I did cut a similar letter with the same bit and cut settings and achieved a buttery smooth finish. This cut was only a few cutting hours before the problematic one pictured in my initial post.

Well, if you’ve used the same but with different results, that may not be the issue. I did have a problem with one of those bits… Wasn’t 60deg.
It could be that your but is not perpendicular to the work. And isn’t spinning on center. I hope that makes sense…

It does make sense, however I would imagine the negative of the edge should be apparent on the opposite side if that was the case? I’m starting to think your suggestion about tool deflection is the probable cause, I will try that next and see how it goes

Runout and tool deflection can show themselves in similar ways. Do you have a 1/8" collet or are you using a reducing bushing? Sometimes just reseating the bit or collet can make a difference.

1 Like

Neil,
when I did the carve you can see the lines but it was smooth, when it was going with the grain it did good but around corners is when you could see the lines. So what do I need to change on my machine to get better results? Sorry to ask questions on your post Matthew,
Thanks Neil,
Russell

V-bits are pretty robust, the best thing to do would be to cut in fewer passes (one if possible). Other than that, if your machine is square & trammed, nothing is loose, then I’d play with your feederate and router speed.
Sometimes, it’s just the wood. I’m no pro…just basing this off experience.

1 Like

Thanks, I will play around with it. That was a test I was doing on a piece of wood that I had. I was using a 90 degree Diablo bit from the big box store.

Check to see if it is an actual V-bit. It looks like it might have a flat tip which might be playing into this. A flat tip that isn’t properly taken into account can cause cut issues.

I will check when I get home.
Thanks Justin
Russell

So I managed to get the cut smooth, but I have a new issue this time. It looks like the bit is missing some areas during the final passes?


I also get this, it can leave step about half way down the cut, I think it looks horrible. I was about ask on here what the problem was.
Have you tried running a second pass? It gives you a bit of confidence that everything is “true”. It doesn’t get rid of the step enough for me to be a complete success.

Are the bit you guys use going deeper than its available cutting edge?

I believe I am. I’m trying to find out the cutting edge online. Otherwise, should I measure the bit with vernier calipers to determine the cutting edge?

Matthew,
How are you securing your work piece down? I just tried a piece of maple using a 90 degree V bit and it did good. I screwed it down to a piece of wood. The first couple pictures is right when the X Carve completed the job. You can see a small line in the V but I sanded it and then applied some stain and a couple coats of matte clear. The last 3 pictures is what it looked like when I was done.