Sienci V-Bit Not "Zero Point" Tipped?

Is it just me, or does the Sienci 90 Degree 1/4" V Groove Bit not have a perfect point?

First runs at a v-carve, or engrave in F360, and cannot get crisp corners on square text and flat bottoms of the carve.

Measurement of the bit show a flat area of about 0.75mm, which would explain my flat bottomed carves and inaccurate corners.

Did I just get a bad bit or is this how they all are? Anyone recommend a good bit with a near-zero point?

@drrkdrrk I have that one from Sienci, and this one from Lee Valley:

I seem to get better cuts with the pricier LV bit. I have the LV 60°, too. Keep them honed and they do a very good job.


Does your Sienci bit have a perfect point? Or is there a flat area at the tip?

I will give the LV bit a try.

@drrkdrrk Derrick: I lied. :grinning: I have the Sienci 60° bits and the do come to a point. The only 90° bits that I have are the LV ones. Sorry for the misdirection.

I just ordered the LV 90° bit, so hoping it works out! Thanks!! Otherwise it looks like Amana bits with the inserts will come to a point, but that’s maybe more money than I want to spend.


Here’s a photo of the Sienci bit with a flat top instead of a point.

You can reshape your V bits with a good diamond file. This is the same way they take the web out of a big drill bit to prevent it from walking when your trying to drill in steel. You can youtube it but this pic with give you an idea.

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Great info. Thanks! I will definitely give that a try.

I was googling this and also seeing if I could sharpen the tip of a flat end-mill. Seems wasteful to replace an entire endmill because the tip is a bit dull. Usually not a problem for through cuts, but I’ve been doing some pockets with flat bottoms and it appears the dull bits can sometimes float above material instead of cutting in to it, resulting in an uneven surface finish.

Just don’t taper the carbide all the way down to the other nd from the tip. Just the back of the tip to help keep it from walking. It could be you had some chatter on the bit too. Make sure you tighten the collet enough. One more thing make sure you don’t bottom out the bit in the collet.

@GregsReinventions Thanks for the tips! Yes, I do not bottom out the bits in the collet to allow for expansion and use the wrenches to tighten the collet.

An update, my LV 90° bit arrived today. The tip comes to a point and the quality looks very good.