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Hi

Does some spruce fuzz up more than others, got great amounts of it on this sitka spruce when cutting purfling chanel .

I have put 3 coats of sanding filler on, I'm using stewmac set to cut and I used different cutter for rosette and it was the same, tried several speeds on laminate trimmer to no avail, oh and I'm following the correct directions when cutting.

Any ideas whats happening and what's the best way to remove this fuzz you have found in your experience

Cheers

How old is the router bit? I get less of that with nice sharp routers, that's pretty fuzzy there.. Cutting direction might cause it too. Another pass might clear a lot of it up. In any case a nice sharp chisel will remove that easily but be careful and don't allow it to rip further back.

Not sure of age of bit as secondhand but it feels sharp. The bit I used on my dremel for rosette is new and still fuzzed up like crazy.

Spruce does this... The wood has really long fibers and is pretty mushy under a cut... Your best defense is sharp sharp sharp tools...

To get rid of the fuzz.....

I use a good square cutoff of wood with a little scrap of 100 grit sticky back sandpaper on it. You don't want to sand the channel - just knock off the fuzz...

Be careful not to break the corner of the spruce or you end up with an ugly gap in your binding.

That's some amount of fuzz.
Looks like you were routing the purfling ledge before the binding ledge. I find that way can pull longer fibres out.
Sharp bit helps a lot. I touch up my bits on a fine diamond hone every guitar binding job, seems to help.
New bits are not a guarantee of sharpness either., especially with a dremel and small bit you can get a lot of that fuzz, perhaps exacerbated because of the low cutting edge speed? WDIK
Do know it's tricky sanding them off, got to be careful. I would use P120 as the coarsest I would try to tackle that with, actually maybe even P150.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I use a Gramil I got from LMII before I put a router to it. Gets rid of the fuzz. On the rosette you can use a popsicle stick and an Xacto blade to make a quick circle cutting jig..... Sorry, these suggestions aren't going to help you with this build. Hopefully it'll help you on the next build....

Sent from my R1 HD using Tapatalk

I've found it to vary quite a bit. I've had tops with no fuzzies, one bad one (not as bad as yours!) and in between. I just use one of those cheap flexible fingernail emory boards (I start with the fine edge and use the coarser one if necessary, but it is still pretty fine. It lets you easily flex around the curves,
Mike

Sitka tends to be the worst, and red spruce the best. I sand the fuzz off with 220 grit, held at an angle with my fingers. Sharpen that bit!

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John

agree with John I also double cut using tape to allow the bearing to ride on I will then pull the tape and do a clean up using a climb cut. Sharpen the bit

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Does anyone have a video on sharpening a bit? I confess that I really haven't clearly understood the written instructions I've seen.
Mike

I don't have personally, but I've seen some on U-tube doing it the same way as I do https://www.youtube.com/watch?v=Q5aQ_RnGxVw for example.
Just clean any crudd off first....methanol/acetone/proprietary cleaner

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Router bits that cut with a shearing action cut much cleaner. Down spiral bits cut more cleanly than up spiral bits.

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

To prevent fuzzy results I use down-cut spiral bits. I get 1/4" and larger from BAM Carbide -- for the tiny one's Drill Bit City.

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Ken Cierp

http://www.kennethmichaelguitars.com/

Thanks so much Colin; that video makes it perfectly clear - I'll start doing that as prep before a binding job,
Mike

I have not a problem at all. I wipe on a coat of shellac first and always thought that helped. but not sure. Sharp bit!!

Just take off the bearing first, and I support more of the card's width to prevent the card flexing, using a wooden block.
I have even touched up 3mm dremel bits for saddle slotting like this.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Yeah, that's a good video, Colin. Thanks for the link.

Like guitarradTJ, I find it helpful to scribe a line with my gramil before making a cut. I have a circle cutting tool that serves the same function for the rosette.

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George :-)