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I've done a lot of high gloss nitrocellulose finishes on guitars. I'm interested in experimenting with satin finishes but I don't know a lot about it as of yet. I recently picked up some Mohawk satin lacquer to experiment with and I was figuring that I would build and level the coats just like I'd always done and then just leave the final coat untouched. In practice it's really not working out for me though because the final coat has an unfinished orange peel look and doesn't look like the professional satin finishes I've seen out there. There must be a few different approaches to getting a great looking satin finish. Anyone know some good methods?

I always shot the satin stuff last....

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"Act your age, not your shoe size" - Prince

Do you mean you shoot and level sand coats and leave the final coat untouched after spraying?

I did all the normal stuff with normal lacquer - smooth and level, and then the final coat I added a flattening agent before spraying.

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"Act your age, not your shoe size" - Prince

Satin and flat finish, last coat wet -- self leveling, no further sanding or polishing.

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Ken Cierp

http://www.kennethmichaelguitars.com/

I'm curious about this. Is there a reason? I use Enduro-Var. I have Gloss, Semi-Gloss and Satin. If I shoot Gloss on to build the finish and then end with Satin do I get a different look or different build than if I shot Satin for the entire schedule?

Colin North had great results (no orange peel, etc..) using a smaller needle in his sprayer. I'm going to try the same this go around with a 1mm needle in the Earlex.

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If you use satin for all the coats you should be able to sand and level the finish similar to a gloss finish (just don't try to buff it out). To do it as an "off the gun" finish you may need to thin it some and/or use a better gun. You should stir the finish prior to shooting to get an even distribution of flatting agents.

Mostly force of habit.
I like to try new stuff, but when a client pays it's best to stick with what you know while still giving them what they want.

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"Act your age, not your shoe size" - Prince

This is the kind of satin look I'd love to achieve. I see absolutely no orange peel or micro scratches from 0000 steel wool or anything like that in the finish on this Maton. The final coat of satin mohawk lacquer definitely didn't look this great for me. Perhaps I need to thin the final coat a lot?

I think the stuff that's in gloss a finish that makes it glossy is somehow harder and therefore less fussy to build, sand and level.
I've always used gloss to build, then a couple coats satin to finish up. Probably could go satin all the way too, without any problem,
I'd bet. Nice looking guitar there James. The satin really goes well on it.
If you're anything like me when spraying nitro I am content with the quality "off the gun" if there is only little sanding to level it.
As guitar builders, most of us aren't spraying every day, so good is usually good enough. If faced with your situation I would take
some time and practice, dial in my spray setup and technique, etc.
Ken

Irving, satin finish tends to hide orange-peel by nature. It is less reflective, obviously. If you're getting visible orange peel after drying, try this:
Lay a wetter coat. It needs to flow together.
Thin it a little bit more.
Stir the contents of the can very thoroughly before using. Some flattening materials can drop out of suspension.

I never bothered to ask what kind of flattening agent the finish companies are mixing in their product, but I experimented back in the 80's painting car parts for one of the nephews. Once I used a pinch of his mother's talcum powder mixed in the lacquer, and another time I used a pinch of corn starch. I liked the corn starch better - it was a finer grit.

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"Act your age, not your shoe size" - Prince

Yes, tried several combinations on test panels with EV, but not with Nitro.
Gloss coats underneath, (4-7), then satin or matt(flat) EV on top, is not so satin (or matt) as flattened coats shot for the entire schedule.
My last guitar finished was all flat coats EV, and was distinctly flatter than the previous one, which was a flat layer over gloss coats underneath.
Only logical it should turn out that way - there's more of the flattening agent for the returned light to contend with on its way to the eye.
The customer (and myself) actually preferred the look. His description was "more organic"
An advantage for me (as a finishing noob) was that it looks quite even, although it is not perfectly flat to the touch.
Some places still have almost a slightly pebbly/textured feel.
(I think this may tie in with the client's impressions in that he's a ceramicist, and works by touch/feel as well as sight)
I used 3 coats , straight off the gun as a final layer, the last two sprayed as soon as the previous one gets touch dry (looses its glossiness about 20/30 minutes depending on thickness/temp/RH)
I think this textured feel is due to some timidness on my part when spraying, fearing sag or runs, and I ends up with some places sprayed on the dry side.
I'm working on it my technique, and thinning the final layers 5% may be worth a try too (that reminds me, I have some extender too)
"Shows promise, but needs more practice"
P.S. Tip of the week - I stir EV with flattening agents really well before use (mechanical stirring, as in with a electric drill) and also between coats (when a stick seems to suffice)

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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.

The way it was explained to me, gloss lacquer is the pure finish and stuff is added to flatten the finish. The "stuff" creates microscopic bubbles in the lacquer to diffuse light, it also softens the finish a bit. Build your finish with the hard material (gloss) and finish off with the look you want.
Right or wrong, I don't know, but it's been working for me.

For satin lacquer, I replace half my usual thinner on the final coat with acetone. This helps the finish to flow out better and give a nicer finish off the gun.

Brad,
For Enduro-Var I've nailed two satin finishes and messed up 2. So far, I've found the smaller tip and General Finishes retarder are pushing me in the right direction but I can't say for certain yet.

Steve

Interesting. Acetone instead of lacquer thinner for the final coat? You find that this levels out better than using lacquer thinner?

For a satin nitrocellulose finish, should the final thinned satin coat ideally be sprayed after the guitar cures for a few weeks? Otherwise the final satin coat could possibly shrink back into the grain a bit. What do you think?

I've never waited to shoot a final coat. Get it on there, let it outgas a week, color sand, buff. Time is money.

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"Act your age, not your shoe size" - Prince

Color sand? What is that? And you buff the satin finish?

Color sand is a term for sanding between coats.
You know - sanding the color...

And sorry - I didn't buff satin, I was thinking glossy at the time.
It was late when I posted... tired and confused.

_________________
"Act your age, not your shoe size" - Prince

No. One half normal thinner, one half acetone.



Yes.

My satin finishes only have a satin top coat over a gloss lacquer base. The satin is softer and not as durable and can be prone to printing if the entire film is satin. I run out my usual gloss schedule except the last coat, let it dry one week for nitro and level sand at 400. One wet flow coat of satin over that with a touch of retarder to enhance flow and that's it.....

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Interesting link here re flattening agents http://news.thefinishingstore.com/index.php/the-role-of-flatting-agent-in-creating-sheen/
Says the sheen is not cumulative and the finish is not softer.
Contradicts my test panels and Howard's observation about hardness...

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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.

Your link was probably written by someone in the finish industry.... Not someone truly objective.

BTW - article mentions that matte finishes can be buffed out. This is true. A fellow brought me one of those Epiphone Dotnecks with a flat finish 2 years ago and asked me to buff out the body. He balked at my price (I didn't really want to do it), so I showed him how to level it with sandpaper, and then go through all the grits of buffing compound. He bought all his supplies, and did it over a week or so while watching TV. When it was done he sent me a pic, and it looked very nice. He left the neck in the matte finish.

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"Act your age, not your shoe size" - Prince

sheen is of course not cumulative...as far as softer or not, I can make no real qualified statement...I think many times hardness differential is mistakenly compared between 2 different products as opposed to the same product with flatteners added or not.

BUT, Chris correctly states the best finishing schedule for use of finishes with flatteners having been added, and that is build up with gloss then 2 (at most 3) layers with the medium rubbed/satin/eggshell/flat product.

the flatteners are micro silica beads that do the job when they lay on the surface and refract light as opposed to reflecting it..of course they are also in the layer also. too many coats with flatteners leads to a cloudy/milky effect. as has been noted, a satin finish can be polished out to be glossier, but because the silica beads are also in the finish it won't be quite the same. nothing quite as annoying as somebody coming up to a one day old spray job of medium rubbed lacquer, finding one spec of hair in it and rubbing on it and bringing that small area to a shine (I bit that dudes head right off)

as has also been stated, one needs to keep the product well mixed at all times...if for nothing else continuity between different projects...if you don't stir it, the flatteners fall to the bottom and will result in different sheens. on such a small area of a guitar it's probably not going to be noticeable...if one has a pressure pot system full of 2 gallons of product and doesn't keep it stirred, the result will be difference in sheen across an entire room of paneling.

I must be missing something regarding some comments above -- the last layer of a finish is the surface that takes the abuse and will show scratches etc., how does a harder chemical underneath help prevent damage? Personally I spray all matte I believe the factories do too. I apologize if I am mis-interpreting something. I am trying to contact the techs at General Finishes to find out if the Enduro Var Gloss actually dries harder than the Matte version.

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Ken Cierp

http://www.kennethmichaelguitars.com/

A softer layer underneath the topmost layer allows dents, scratches, and crushed areas. A harder layer underneath the topmost layer (even one a bit softer), provides firm, stable support. Think of the lower layers as a foundation. Soft foundation = no good for buildings or guitar finishes. Hard finish = good to go.

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"Act your age, not your shoe size" - Prince