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Has anybody brushed Crystalac Brite Tone? Iʻm starting to varnish an OM type guitar - Iʻm at the wood grain filler stage, seal coats tomorrow. Iʻve been watching Robert OʻBrianʻs YouTube test of the product, among others - https://www.youtube.com/watch?v=m1EFuyD3qq8 - and writing up a page of his step-by-step process - when I use a new product, I like to have a printed page that I can follow and scribble notes on.

His video is very thorough and useful except for one thing - heʻs not clear how many coats of Brite Tone he brushed. It seems that he brushed 4 or more coats, doing his first careful leveling sanding pass after the 3rd coat. But he also seemed to say he brushed 3 coats,day over 3 days, leveling after his 4th coat. Thatʻs a lot more coats! - and though I keep going through the video itʻs just not clear.

I expect itʻll make more sense once I start with the Brite Tone coats, but if anybody has brushed Crystalac Iʻd be interested to know how many coats you usually end up doing.

I also have a question about final finish. I know you guys do a final coat, then sand and buff. Itʻs a different in the world of violin making - no buffing on a wheel, and I donʻt have a buffing setup. BUT - Iʻve done a lot of small art woodworking projects - jewelry boxes, picture frames - using Micromesh. Iʻve brushed Minwax Polycrylic - itʻs easy to do multiple coats on small objects quickly as it dries very fast. After my final coat, I dry sand 400 and 600, then start in with Micromesh. Iʻve used Minwax gloss, semi or satin depending on what I want for finish, and varied how far Iʻve gone with the Micromesh.

Have any of you played a lot with Micromesh? Iʻm wondering if I can get a good gloss finish by using it right up to 12,000 grit or if I need to bite the bullet and get a buffing setup. I know I can do it on an 8" x 10" jewelry box, but guitars have a lot more real estate to polish.....

In response to your micromesh question, I used to wet sand with the 2" x 2" pads and was able to get a nice gloss finish.

This finish below was done by wet sanding with micromesh pads 4000 through 12000. I didn't have a buffer then so this is where I stopped. It was tedious but it worked well.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Thanks Jay, thatʻs pretty much what I have in mind. Iʻve always used Micromesh dry - Iʻve used both the cloth backed sheets and the foam pads. I can of course try wet. Since this is a first guitar and somewhat of an experiment, Iʻm not in a hurry - no way a production instrument!

Hereʻs a quick update on the thread. My guitar is now playing. The Crystalac process worked well. The pore filler step was my "least best" step, as I didnʻt work carefully enough to get all pores well filled. Next step was brushing the sanding sealer. When I started to apply coats of the Brite-Tone I immediately could see that I had some pits where I hadnʻt done well enough with the pore filler. Better next time - for this run, I simply did a few more coats and sanded them pretty far down.

The Brite-Tone brushes on easily and levels well. I tried both foam and good quality bristle brushes, and I was surprised to find how well the foam brushes worked. I generally tried to apply several coats over the course of a day, with at least 2 hours between coats, sanding more or less depending on where I was in the process. Then Iʻd let it sit overnight and sand more thoroughly the next day. I ended up with around 6 coats or so.

Even after a few hours drying time, sanding produced mostly fine powder - the sandpaper didnʻt clog very much at all. I keep a matt knife on hand to knock the small clogs off the paper so they donʻt rub and mark. After overnight drying I got almost no clogs at all. After my final coat I waited more than a week but less than 2 weeks before starting the final sanding and polishing. This is hearsay, not personal experience, but Iʻve heard that if you donʻt wait long enough, you can buff up to a fine smooth shine, only to have little spots develop where the surface settles - micro-craters, so to speak. And then youʻd end up resanding and polishing. So I tried to be patient, though I didnʻt make the entire 2 weeks.

After my final coat I sanded with 600 and 800 grit paper, then I started with Micromesh. I workeed dry in all cases, but Iʻd like to do this again sanding wet and see how it works. I went up to 12,000 Micromesh, hoping that would give me a good final shine, but it didnʻt. It turns out that I live near Alan Carruth, and I spent a lot of time with him talking things over as I worked. He has had problems with Micromesh leaving scratches, and I also had those problems - so these days he sands and doesnʻt Micromesh. He does final hand buffing/polishing with Novus #2 and #3. I tried this product on my Micromeshed surface and it came out quite well. So my next try would be with high-quality sandpapers as fine as I could go -Alanʻs suggestion was Mequiar Unigrit sandpaper - it comes in 1000, 1500, 2000, 2500 and 3000 grit. Then rub out and polish with Novus products - you can buy sets of their #2, #3 and fine polish on Amazon.

True confession: I rubbed through in a few places on the back and 2 tiny places on the ribs, so at some point Iʻll have to recoat the guitar gody and polish it up again. But itʻs fine for the time being - this is an experimental guitar and now Iʻm into the intonation issue - but thatʻs material for a separate post.

So - Crystalac turned out to be easy to use; it flowed and leveled well, sanded and polished well. As a violin-maker, I like the hand varnishing process, and Iʻll certainly be using the Crystalac products again.

Crystalac Brite-Tone is my go-to.

I use the super Assilex and super Buflex sandpaper, though, and don't wet sand. Assilex is expensive but really lasts and gives a great result.

+1 fr the Assilex and Buflex. Best abrasives you can get IMHO.

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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.

Wet sanding any water based lacquer is an absolute NO NO, dry sand only - Mirka Galaxy or as others have noted - Super Assilex and Bufflex is the way to go. StewMac stocks it and the price is reasonable relative to other vendors.

I am a big fan of Crystalac products and used it for the first time with a Fuji 3-stage HVLP. Crystalac has an excellent users forum on Facebook with experienced product users that can answer any question you might have. My recommended Finishing Routine:
• Sand guitar to 220 grit (320 grit if maple)
• Spray or brush 1 or 2 coats of Crystalac Sanding Sealer (Amber toned) over entire guitar, sanded back to wood with Mirka Galaxy 600 grit paper
• For maple, stain the body and neck with Warm Tone Dye Concentrate mixed with Crystalac – Craftnique Gel Stain/Glaze applied with cotton t-shirt
• Three sessions of Crystalac Clear Wood Grain Filler on the mahogany neck (level sanded between coats and let cure a couple hours between coats
• 5 coats of Crystalac Sanding Sealer dyed with Warm Tone Dye Concentrate, level sanded with Mirka Galaxy 800 grit paper between coats
• Surface cleaned with Crystalac Surface Conditioner
• 12 coats of Crystalac Brite Tone gloss, surface cleaned with Crystalac Surface Conditioner between coats, 3 coats per day over 4 days (first 6-coats mixed Warm Tone Dye Concentrate) last 6 coats shot clear
• Spray equipment – Fuji Mini-Mite 3 turbine and Fuji T75G gun (started with a 1.3 mm needle and went to a 1 mm needle)
• Cured for approximately 22 days then level sanded starting with Super Assilex 800, 1000, 1200, 1500 grits, then Super Buflex 2000, 2500 and 3000 grits. Alternated sanding direction with each successive grit
• Left lacquer to cure for additional 8-days – 30 days total, buffed with Menzerna Medium, Fine and Extra-Fine polishing compound on 12-inch 16-ply canton cloth buffing wheels at 863 RPM.
• Final polishing with Menzerna Power Lock Ultimate Protection applied and buffed with a clean cotton rage
Lessons learned:
• Fix runs and drips between coats of Brite Tone rather than wait to final leveling stage with a razor blade, then sand flat with 600 or 800 grit
• Super Assilex is superior to Mirka Galaxy sandpaper, lasts longer and cuts better