Advice needed - patching sanded-through top

[Jehu]

Hi all,

I'm building my first instrument (an archtop -- yikes!), and I need some advice on fixing (/hiding) a flaw. I made a mistake carving the inside of the top plate, making one area of the rim far too thin. I patched the inside for a bit of extra support, but then got carried away on the outside and sanded through to the patch. (Photo attached)

Any thoughts on how I might go about reducing the visibility of these two spots (the biggest is ~2mm)? I've thought about mixing up a slurry of matching wood dust and shellac, which would not discolour the surrounding wood. However, I plan to try my hand at a French Polish and I wonder if once I start finishing it would just dissolve my fix.

Thanks!
Jay

[peter.coombe]

That is a real tough one to hide. French polish will make it shine out like a lighthouse no matter what you use to fill the holes. I would chalk it up to experience (i.e. don't do that again), finish the guitar, play it and learn some lessons on guitar building, and start the next one. Or alternatively fill the holes and stain the top black. You could also replace the top, but I assume you don't want to do that. Easiest would be to stain black and turn it into a blacktop, which can look quite nice with some colouring on the back and sides. If you want to use a shellac finish, use a water soluble analine stain and brush on the first few coats of shellac to seal the colour in before French polishing. Good luck.

[simso]

Use an airbrush and you can turn them into knotts we have done this on many punched through holes, makes them a feature, do not try to hide the area (make it dis-appear), emphasise it instead

Steve

[Kev3]

Have to agree. You'll have a hard time making that go away. Even shellac & dust fill will likely be darker and youll never match that grain, colour variation running through.
If you can't live with it as a first time build and don't want to go the stain the lot approach - turn it round and make a feature of it.

... And wow, way to go for picking an archtop as your first build !

[Jehu]

Thanks for the responses, all. I would quite strongly prefer to not make it a black top, so maybe I will take the advice to try to make it a 'feature', rather than trying to cover it up.

I wonder would a touch-up pencil/crayon help? (I have no experience with airbrushing.)

Otherwise things are ticking along quite nicely!

[charangohabsburg]

If you don't want to get into serious restore techniques (such as what you can see in Matthews "Old French Bass Full Restoration"-thread), make it a feature, maybe something crazy like an abalone dot inlay.

Painting does sometimes not turn out very attractive:

20 Oops.jpg (88.92 KiB) Viewed 23218 times

P.S. Nice work!

[ozwood]

A Tobacco Burst would hide that OK and still look nice, you can practice on a sheet of ply cut into the shape of a guitar until your confident.

Cheers,

[Jehu]

Thanks, folks. I'll have a think and evaluate my options.

[lauburu]

+1 for sunburst but do the faux knot treatment first. That way it will look like you're trying to de-emphasise a couple of knots rather than stuff ups.
Miguel

[ckngumbo]

On one of the forums. . . (sorry old and forgetful) a guy inlaid some small pearl dots to conceal worm holes in the back of his build.
Honestly, they just looked great, sort of the same "celebrate the anomaly" thats been posted already.

[charangohabsburg]

On one of the forums. . . (sorry old and forgetful) a guy inlaid some small pearl dots to conceal worm holes in the back of his build. [...]

Maybe you are referring to this case here on the ANZLF?

[ckngumbo]

On one of the forums. . . (sorry old and forgetful) a guy inlaid some small pearl dots to conceal worm holes in the back of his build. [...]

Maybe you are referring to this case here on the ANZLF?

Well yes I was! Thought it was a brilliant fix.
Thanks for having more cognative cells than me

[old_picker]

yep sunburst would be the way to go
i would use a tobacco sunburst as it is quite dark and opaque at the edge
not how you pictured things i know but less obvious than a fake knot - unless you are very handy with a brush

[Jehu]

Thanks for the additional comments, all. Very interesting solution with the paua dots on the back of that build. I will have to digest this a bit -- I'd prefer not to do the sunburst (or black top). I'm not sure how it would look with the black binding... I had really envisioned a lighter (medium/dark blonde) finish.

[dshaker]

Alembic, the high-end electric guitar makers in California in the 70's: "No problem, just put an inlay over it."

[Jehu]

I may have to steal that motto!

I will say this: The guitar has other warts as well. I've done my best with them, but in the end I am willing to live with them. I was just hoping that there might be a simple-ish way to make these particular warts blend a little bit better, realising that they're not likely to disappear entirely.

This is my first attempt at learning this craft and mistakes were made. I will finish this guitar, play it, love the crap out of it, and the next one will be better.

[Nick]

I'd prefer not to do the sunburst (or black top). I'm not sure how it would look with the black binding... I had really envisioned a lighter (medium/dark blonde) finish.

The burst can look nice on an Archtop, very traditional. I've built both a blonde and a tobacco burst and my preference is for the burst, it just enhances the flamed maple

IMG_2987.jpg (177.92 KiB) Viewed 22960 times

But as this is your first build you probably are intimidated by the prospect of doing a burst plus if you haven't the gear, it can be a costly exercise getting setup for spraying. You can do a "rub on" burst (as per a tutorial I did a while back viewtopic.php?f=5&t=5392).
Other than that, Steve's knot idea is a viable way to go. What timber is the top? It looks like spruce in the whole top pic but different in the close ups. If it is a slightly darker timber then you could try mixing up some stain to match and with careful use of a fine point brush you can do a fairly invisible repair. Dan Erlewine once had a trade secret on how to repair chipped rosewood fingerboards where he re-coloured wood and even added in fake grain lines.

[Jehu]

Don't get me wrong, I love a good sunburst! And thanks for the link, that is one hell of a tutorial you've posted. I've thought about giving a hand-rubbed sunburst a try at some point, so I've bookmarked that for later. You're right about the cost of spraying equipment being an inhibiting factor at this point. I notice that you use Stewmac stains in your tutorial -- is that your standard, or do you happen to know a source for that sort of thing that is local to NZ?

All the wood is Macrocarpa/Monterey Cypress, except for the fretboard and veneers which are Puriri.

[Nick]

Don't get me wrong, I love a good sunburst! And thanks for the link, that is one hell of a tutorial you've posted. I've thought about giving a hand-rubbed sunburst a try at some point, so I've bookmarked that for later. You're right about the cost of spraying equipment being an inhibiting factor at this point. I notice that you use Stewmac stains in your tutorial -- is that your standard, or do you happen to know a source for that sort of thing that is local to NZ?

All the wood is Macrocarpa/Monterey Cypress, except for the fretboard and veneers which are Puriri.

Yes I use the colortone stains as my go to stains, brilliant at mixing with any medium (water, alcohol, lacquers,polyurethanes), they're colourfast so don't fade in direct sunlight and if you just open the tip with a 1-1.5mm drill you have a good way of mixing, i.e. the drops are consistent so a mix of twenty drops to 100mls of base medium (say water) will be the same shade everytime you mix a fresh batch. They don't separate in mixture either, I've used powders in the past and no matter how well you mix it initially, six months later I come back and there's 'clumps' of powder or solids settled on the bottom. Unfortunately I've never found a similar product locally and if there was I would suggest it's been imported.

Macrocarpa a? I would be interested to hear a sound clip once you've finished the guitar, just to hear what a Cypress top/body sounds like compared to the 'normal' Spruce and Maple. No shortage of Macro in NZ! Being a slightly tanned colour, you could mix a very weak mixture of Medium brown in either water or alcohol (being aware that water will raise the grain!) just to colour up the patch material for a better blend. What part of NZ are you in?

[Jehu]

Thanks, Nick. I am in Auckland.

I will make some sound clips once the guitar is finished, but if they're less than stellar I don't think we can blame the Macro!

[Jehu]

Alright Nick, your tutorial has sold me on the tobacco burst and I've got the stains on order. Now you've done it... you'll have to deal with a bunch of silly newbie questions!

I'll start easy and work my way towards the truly forehead-slapping as we go:
1) Should I do anything to prepare the surface aside from sanding (e.g., sealer coat of shellac)? I assume I don't need to pore fill macro.
2) Do you have a recommendation for a locally-obtained clear coat?

Thanks!

[56nortondomy]

Keep asking Nick questions Jay, i've printed off Nick's tut for a burst i'll be doing later in the year ( my first ) and any extra info will come in handy.
Wayne

[Jehu]

Bumpity in case Nick wanders back...

[Nick]

Bumpity in case Nick wanders back...

Sorry, was washing my hair
Right where were we? To your questions
1) No, Macro has relatively small pores so you will get away with missing the pore filling step if you want to(see last part of answer 2), any small pores will fill when you apply the finish/top coats.
2) I've used many different types and brands of finish, I'm currently using the Mirotone brand of finishes and am more than impressed with it, easy to apply, dries well and takes a really good polish. There is a branch in Auckland (what am I saying?? It's their head office!): Mirotone (NZ) Ltd,32 Cryers Road and the finish you want is their Pre-cat 3220 lacquer http://www.mirotone.com/products/wood-c ... -lacquers/. They also do the 3241 sealer if you really do feel you need to pore fill.
*Caveat* I've never used the Mirotone sealer and there are different opinions as to it's use here on the forum (some say don't use it and others swear by it! ), but I will get some and try it at some stage to see for myself if it's a good move.
You can also use Acrylic Lacquer available at any car spraying store,it does take longer to dry and harden than the 3220 though, my personal choice is the Mirotone.

Hope this helps and remember there are no dumb questions only dumb answers so keep 'em coming .

[Jehu]

Fantastic, thanks Nick. I assume I can brush on the Mirotone? The instructions only mention spraying.

Also, is it thinned with mineral spirits? The data sheet prescribes "Mirosol" thinner, but I can't seem to find a description of what exactly that is.