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Hey gang -

Here's my first stab at a rosette - just a few scraps of walnut, maple and granadillo lovingly glued together, frustratingly inset into a nice engelman top with a wandering dremel....but all in all, it looks pretty neat.

Question - what can you do about a slight (very slight) amount of tear-out around the rosette?  It doesn't show up in these pics, it's actually on another duplicate sitka top.  Should I mix a little sitka sawdust with some CA and dab it in?

Looks great from here...I really like the pattern.

I had a small amount of tear out on my 1st top that I sanded out carefully. Where is the tear out??? Can you hide it under a pick gard (it's cheating, but, I won't tell if you don't)

If a pick gard isn't going to work out for you, then a repairing we must go...

I would wait for a response from some more experianced folks, but, from my previous life building many a model airplane...DON'T use CA...this will turn yellow on you and stick out worse than the tear out. I'm thinking you could probably add some pieces of sticka using yellow or white glue and sand smooth (kinda patching it)...OR just make a wood filler from white or yellow glue and dust taken from sanding this top.

Good luck and try to post some pics of the tearout...
Thanks,
JP

It's almost impossible to hide tearout on spruce. If it can be hid under a
pickguard that would be ideal...if not maybe a sunburst is in order.. if not
that you might just have to live with it. The rosette looks pretty cool!

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John Mayes
http://www.mayesluthier.com

In future, shellac the spruce first. It'll help with the tear out and easily sand off afterwards

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CRAIG LAWRENCE of AUSTRALIA
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Shellac the top first and also watch runout direction when routing channel.

People take great care in direction of cut when doing the binding channels to avoid tearout, making all the right climb cuts etc. But when it comes to the rosette channel just rotate the cutter in a circle. Use the same practice on the rosette as with the binding channel and tearout is greatly reduced.

Can't post a picture so here goes with 1000 words!

Rotate from 12 o'clock to 3 o'clock, then from 6 to 3, from 6 to 9, and from 12 to 9. then one turn right round. Of course take the precaution of shellacing first.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

to hide a bit of tearout, difficult, try putting a little LMI white glue on it and sanding over it so that the dust goes into the glue.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

http://www.cvwoodworks.com/

Jon, nice design, I really like it. Nothing like a bit of "originality" thrown into a great guitar build.

Will have a look at your website now. Go Jon. Sorry about the tearout, it happens, what bit were you using?

Bruce

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http://www.dickeyguitars.com

Jon, nice stuff on your site. You'll be a natural at acoustic guitars.   

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http://www.dickeyguitars.com

Hey thanks to everybody once again for all the info (and kind words!).  I'll shellac the top next time...hadn't thought of that....and try cutting the circle in quadrants, also.  The tearout I mentioned is pretty slight..I'm confident that the white glue/sanding idea will work just fine.

I used a straight Dremel bit (StewMac) in a jig I sorta patterned after their rosette-cutter, which needs a little reworking itself.  Long story short, the Dremel is too high off the surface to be cut, the bit extended too far...that's where I think my "wandering" comes from.  However, the outer and inner purfling went in just fine with a little sanding, and really rounded out the entire design.

The Engelman top routed out just fine, but the Dremel wanted to BURN its way through the Sitka.  Is that typical?  Maybe the Engleman was drier or something. 

Will post other pix as things progress.  And thanks again for all the replies!

Jon

Jon, to hide a little tear out, or other problems in spruce, I would definitely steer clear of using CA as your binder for the dust. Use good 'ol Elmer's...or some such white glue. And, I haven't had good success with top dust, as the glue always darkens it some, leaving a darker fill. What I've done with success is raiding my wife's pantry for useful things like baking soda, which when mixed with a little white glue dries into a shade not far from spruce. Throw in a little powdered ginger if you want to introduce a hint of amber.
You get the idea. If you want to be obsessive about it, take a scrap of the top, put some dings in it, and try several different mixes of fill. Let them dry, then see which formula works for your top.

OR-- and this might make more sense yet-- isn't LMI marketing a spruce patch kit? Several different shades to fill nearly any type of top. I want to try that.

Good luck,
Steve

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From Nacogdoches...the oldest town in Texas.

http://www.stephenkinnaird.com

[QUOTE=Colin S] People take great care in direction of cut when doing the binding channels to avoid tearout, making all the right climb cuts etc. But when it comes to the rosette channel just rotate the cutter in a circle. Use the same practice on the rosette as with the binding channel and tearout is greatly reduced.

Can't post a picture so here goes with 1000 words!

Rotate from 12 o'clock to 3 o'clock, then from 6 to 3, from 6 to 9, and from 12 to 9. then one turn right round. Of course take the precaution of shellacing first.

Colin[/QUOTE]


Colin, as small as a rosette is, why not just climb cut one whole revolution then go the other way? Actually, I've just been doing it clockwise only on my rosettes, which is a climb cut, and no tear out on the three I've done.

Ron

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

The spiral downcut bits from Stewmac work well on rosettes . Turn clockwise . Englemann definatley needs the shellac.


    Lawrence of Australia

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CRAIG LAWRENCE of AUSTRALIA
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