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I've been finishing with aerosol lacquers for the last 5 years. The working properties are good, they buff out nice, but IME the finish is too soft, so I have switched to professional spraying lacquer(Behlens). Right now I don't have a compressor, so I have decided in the interim, until I can acquire one, I'll be using the preval rigs.
I am used to using the lacquer as a sealer, just shooting enough until it seals the wood and begins to build. I want to continue this practice with the Behlens.
Now, I know a ton of you would not recommend skipping the vinyl sealer. But I have done an extensive search here and elsewhere, and I'm aware of the pros and cons. I'm also aware that there are a few well respected luthiers who use the lacquer as a sealer as well. I'm not trying to debate this, and I'm not looking to be talked out of it; I've chosen the course of action I'd like to take, and would simply like to ask a few questions that I haven't found the answers to.
Firstly, I've read about a washcoat, or a heavily thinned lacquer application that most use when sealing with lacquer. Can anyone give me a ratio, thinner to lacquer, for this?
Also, I'll be using zpoxy as a pore filler. Does anyone do this successfully using lacquer as the sealer?
Thanks.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

10% lacquer for wash coat

DuPont 1980 S sealer works well as a sealer under lacquer.
It's water thin, and requires no reducing before shooting.
It's like shrink wrap in a can.

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

I used to use vinyl sealer under nitro, but quit. Got tired of ordering it separately. I can't tell the difference between with it and without it.

Mike: I fill with zpoxy and then spray regular coats of nitro for the body. For necks I use regular pore fill and seal with shellac. Have used various finishes on necks. Padded shellac is my favorite at the moment. Works for me, but I am no finish guru.
Tom

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A person who has never made a mistake has never made anything!!!

Thanks for all the replies. Got what I need. Much appreciated.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

lacquer won't stick well to some woods without a matching vinyl sealer. You may be able to shoot it and buff it OK, but when bumped lightly or sometimes if you look at it funny it will de-laminate from the wood. And it's not just oily dense woods... this is mahogany after a tiny tap that didn't come anywhere near even cracking the lacquer:

Thanks, James. Yeah, I've read that. But I've also read that lacquer doesn't adhere that well to vinyl sealer, which is the reason some folks use shellac in between.
Don't know which is correct, but I have used straight lacquer for five years with no problems whatsoever. And I'm incredibly accident prone; all of my guitars get hard knocks and dents. Sometimes deep ones. Never had a delamination of any kind. I'll risk it.
To be fair, I've also read that adhesion problems between lacquer and vinyl sealer depend on how long the wait is between when the sealer is laid down and the first coat of lacquer is applied. The sooner the better is the consensus I got. But I don't have any fear of delamination.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Thanks, Todd. 50/50 sounds more like the ratio I read for the sealer coat(s). It was here on this forum, but I've searched and searched and could not find it.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Mohawk vinyl sealer is lacquer based so I suppose the same is true for other manufacturers. Their system provides a molecular bond to their lacquer topcoats following the directions.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

Depends on the exact lacquer in question, some need a vinyl sealer, some not. The industrial lacquer I use will not work well over a vinyl. Best practice is to use the sealer recommended by the manufacturer. They engineered it as a coating system. Most modern lacquer have lost their self sealing abilities due to environmental compliance.

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Brian

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

https://www.howardguitarsdelaware.com/

I know what you mean James. I've had the same thing happen more than once. How fresh is the finish? I'm beginning to think they are more prone to delambs like that before they have fully cured, like less than a couple months old. I'm not to careful with my guitars and it seems after a period of time they are much less prone to that sort of thing. I use nitro and have had it happen with all different sealers.

Most finish Delamitation has its roots in the prep work. Sanding out too fine is a common cause. The finish needs a surface with enough texture to grip onto. This can happen between wood and sealer or between sealer and lacquer in the case of vinyl sealers.

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Brian

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

https://www.howardguitarsdelaware.com/

This guitar was several years old and in the shop for a new armrest bevel, so definitely not still curing/drying.

Brian brings out a few points that need to be listened to. Most instrument lacquers are formulated different from furniture finish. Prepping is 90% of the end result and shellac and lacquer may have compatibility issues depending on the brand and formulation. Do not assume shellac will work. Today finishes are as much about chemistry compatibility . I do not sand much past 180 grit.
The sad thing about this is that things can look good for years then bingo finish peeling.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I don't trust shellac... I had finish peel from shellac before.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Brian, what do you consider too fine? I've always thought that 320 was the finest I would go to before finishing.

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Steve Smith
"Music is what feelings sound like"