V-Groove question

[Ryan Harrington]

Good evening all,
This may just be a naive newcomer-type question, but I'm sure someone out there has an answer for me... This afternoon, I was routing some v grooves in a board (maybe 1/8 deep), and I noticed that they were a bit on the fuzzy side, especially toward the bottom of the groove. Is this normal, a junky router bit, poor technique, or some combination?

Thanks,
Ryan

[Will Overton]

Could be the bit, or the wood. It isn't uncommon.

One way to get rid of the fuzz is to run the router in the opposite direction (climb cut) after first cutting the grove.

[glenn bradley]

I vote for bit sharpness however, you do not state the type of wood. Soft woods mill more poorly than hardwoods so if it is pine or fir I would say "that's just the nature of the beast". Reversing direct may help and in this type of cut (captured cut) there is not real forward or backward. Your technique one direction would be the same as the other direction.

[Danny Hamsley]

Could be that you are routing against the grain.

[Peter Quinn]

Is the wood dry? Moisture can cause this problem, so check that if you are able to measure it.

Also most climb cutting leaves a fuzzy surface. Climb cutting may control tear out but it will NOT improve surface finish quality. And when you are routing a V groove, at least one side of the groove is a climb cut on each pass. The suggestion to pass once in each direction may help as you will be removing the fuzz created by the climb part of the first pass. Or a sanding block cut to match the angle of the V may help clean things up too.

Additionally, try varying the speed of your passes. Perhaps a bit slower will come out cleaner, though too slow will lead to burning which is no joy to remedy either.

[johnny means]

V-bits always cut badly toward the bottom because the cutter speed towards the point tapers to zero. The point of the bit is essentially not moving, therefore, you are just dragging the bit through your material at the point of the bit.

[Karl Brogger]

Sand it off?

[Will Blick]

I am with Johny on this one.....

a V Groove cut is not an "ideal" router cut, for the reasons he mentions. If you are trying to cut a 90 deg V groove, try a circular saw or table saw set at 45 deg, the cutting action is more true, but still not ideal...

The best approach is a V groove hand plane, such as those sold by Bridge City Toolworks... or, you can get a Magic Moulder, with a V groove insert.... it should perform as good as the V groove hand plane...

[Will Overton]

Reversing direct may help and in this type of cut (captured cut) there is not real forward or backward.

So true. What was I thinking :o

[Ryan Harrington]

Thanks for all the great info. What I'm doing is routing the v groove along a glue line. I have thought about using a chamfer on both sides before glue up, but my concern was getting squeeze out in the groove and not being able to get it out.


Thanks,
Ryan

[john bateman]

If your groove is near an edge, you could use this type of v-grooving bit:
http://www.mlcswoodworking.com/shopsite_sc/store/html/smarthtml/graphics/bt_flvnc.jpg