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You know. When you've been struggling with something for so long, and you see the solution. No, not life, I don't have a problem with that. With surface finish on backs, tops, sides.

I make my own fittings, and fingerboards. I've been filling with CA, and scraping, and sanding until the shine is all gone. 1-3 or 4 times does it.

Why not do that with the rest of the instrument?

Duh.

Seal with shellac. Sand. Keep doing it until there are no more shiny spots! Now that is what I would call a "sanding gage" not a sanding filler. You gage your result until you are done. I've never seen anyone say that except when filling pores. But you have to get it SMOOTH way before filling pores. I never heard anyone say to do that when doing the shaping, and final sanding. Maybe I just wasn't listening.

The walnut tailpiece doesn't really have pores. It does have flame, and a couple prominent grains, and some small knots. When it is all smooth, you don't even KNOW it has CA on it. It still has a few spots to fill on the underside.



I would imagine that doing a body with shellac would be the same. I did z poxy on the first archtop, but wasn't paying attention to finish; just getting it finished! I worked, but I COULD have got it a lot smoother.

Well the next ones should have other problems. I already found one on the walnut violin. The finish is fine. It only needs a bridge and strings. But somehow the last peg in the pegbox is at a 20 degree angle! How in the world did I do that? I drill them with the profile cut out, but the sides still full thickness. The last hole I got chips under it or something when moved it?

Making instruments always seems to involve repairs of some kind. Now I get to learn how to plug, and relocate peg holes.

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Why be normal?

Those 'when it clicks' moments are nice. Haven't made a guitar yet that didn't get at least one or two minor repairs. Fortunately I'm past the point (hopefully!) where I have to replace major assemblies like necks, tops, or sides due to something I screwed up.

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Steve Smith
"Music is what feelings sound like"

Shellac dissolved in alcohol is no good for filling. It shrinks too much. But you can use heat to melt solid shellac into divots. That's what I do for anything that won't steam out.

How do you apply CA to something like that tailpiece? I've heard of people padding it on like shellac, but anytime I try it, the cloth or paper hardens instantly and would scratch the wood if I tried to rub with it.

I've been trying to up my finish game and knew I had to start with the pore fill end of finishing.

I had perfect candidates in wood with padauk and macassar. Padauk is like canyons and macassar has tons of smaller well distributed pores. I probably had 20-30 test coupons going before I even touched the guitars.

Best fillers IMO were GluBoost and System Three Silver Tip. I tried severl other fillers too. On the test coupons I was favoring the CA because there was virtually no cure time and the end results looked as good as the epoxy.

I'd used ZPoxy before but never CA on a whole guitar body (back and sides). I had too much invested in the macassar to try something new on that so went with Silver Tip. One padauk was a commission I didn't want to try an unknown filler on, and the other padauk was an unclaimed guitar so I tried the CA on that one.

2 coats of epoxy on the macasser and I had a near perfect fill. It took 3 coats of epoxy on the padauk to get there. The first coat CA went on very smoothly with a credit card. The second coat went on rougher and seemed to kick much quicker than the first. (I didn't use any accelerator) Sanding back between coats, the CA was harder to sand and new pores kept opening up. I ended up doing 3 full coats of CA and still had pores. I ended up chasing pores with a micro pipette. Of the 3 guitars, the CA was the biggest PITA and produced the least perfect fill.

I think the CA was starting to kick before being pushed into the deep pores far enough (educated guess).

I'm not trying to condemn the CA and think it has a lot of potential. But on wood with huge pores I would go with epoxy. The padauk was soo porous I kept looking inside the body to see if CA was running right through the pores and making a mess inside -- that did not happen. If I try it again I would start with thinner CA and hope it gets to the bottom of the pores w/o running right inside the body.

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Brian R, Wood Mechanic
N8ZED

Dennis,
I used a little folded up square of paper towel. A couple drops. Rub on fast. I could do the whole piece no problem with that. No real pores. I used the thin CA, I think it soaks in faster. If you have real pores, maybe medium would fill faster.
Brian,
I've done a Padauk guitar, and a violin. I wouldn't try CA with it. AquaCoat worked great on the violin; but I really don't like the look of AquaCoat at all. Too blue for me. So I tried wood dust and varnish. It worked good, but somehow, after getting the finish spoiled around the edge past the color coat, when sanding it back Iost some of the fill.

Now; maybe I just needed to sand the AquaCoat back to wood. I probably put a thin coat on after getting it smooth, like I did with the Z poxy to make it pop. AquaCoat won't work like that. It looks ugly.

I should have used the Z poxy. Is there any shelf life on that stuff? It was pretty easy to use.

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Why be normal?

I tried AquaCoat in my test coupons and even after a bunch of coats, it just wasn't working for me. Tried several pore fillers on the padauk. But man, when you get the finish right on padauk, it is so gorgeous it is worth the effort.

One of the more successful fillers I tried was a 3M Ebony Wood Filler. Quick and easy but I didn't like the look on padauk. Liked a clear filler better so the pores were not so dark.

Thought I should stock up on the 3M stuff but as usual, find something you like and they quit making it. I bought 6 more tubes on ebay just to have it on hand.

I like the System Three a lot, even a little more than Z-Poxy. I think that's my new go to filler.

I've had Z-Poxy on the shelf for 5-10 years and it still works like new. Seems to get a little darker amber over time.

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Brian R, Wood Mechanic
N8ZED

I struggled with the water based grain filler. I couldn't get it to work for me. I was trying to get away from Z-poxy, but Z-poxy just looked SO much better to me.

I too, have had epoxy that is 20+ (Tower Hobbies, not grain filler) and 10+ years old (Z-poxy finishing resin) that still sets up fine but gets VERY amber colored. The funny thing is, I bought some StewMc epoxy which I didn't open for a year, went to use it, and it was rock hard. I complained and they sent me some more, and it set up rock hard too. My moral is not to buy StewMc epoxy.

Does Silver Tip turn amber over time? I've heard that it is much more clear than even brand new Z-poxy. True? I've also heard that it is harder to sand than Z-poxy. True?

I

I have not used Zpoxy, so I can’t compare, but I have used Silver Tip several times as a pore filler. It stays water white. I don’t consider it hard to sand, but again, I can’t compare the two. I think Silver Tip works great as a pore filler. It is picky about the mixing ratio, so I recommend measuring by weight instead of by volume.

Re-reading my earlier post it may seem I was saying Z-Poxy darkens after use. What I was referring to was unused hardener getting darker over time in the container it comes in.

In my epoxy use over years I have seen cured epoxy yellow over a long period but that was when exposed to sun, weather and atmosphere and not when being used as a pore fill or thin film under finish. Those uses were not finishing resin either.

Here are a couple pics to demonstrate. The Silvertip hardener is much lighter in color and is mixed 2 pts resin to 1 part hardener so is a very light amber when used. In the second pic the darker Z-Poxy was bought in 2012 and the fresher bottle is about 3 years old. But you can see how the hardener has darkened. Z-Poxy is mixed 1:1 so it is darker from the mix ratio also.

I like the SilverTip and it sands very well. Only down side is it takes a bit longer to harden than Z-Poxy. It's been a while since I used Z-Poxy but I don't recall it being difficult to sand.

I tried SilverTip primarily for the "blush proof" promise even though I never really had problems with Z-Poxy and blush in typical applications.

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Brian R, Wood Mechanic
N8ZED