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Hello,

I'm closing in on spraying finish onto my first build. I actually have two that are close to ready. It was originally three but I was getting overwhelmed (go figure). I'm starting to get that "bogged down" feeling that others mention in the new builders threads. Mostly because I don't want to ruin anything at this point.

Here is where I am:

1) Bodies are finish sanded and pore filled with 3 layers of z-poxy and leveled out.
2) Necks have been final fitted to the body and need to be carved and z-poxied.
3) Fingerboards are attached to the necks.

My assumption is the next steps would be:

1) Do the final wash coat of z-poxy on the bodies. The process here is z-poxy with 10% DNA and thin, thin coat. Level out after drying with scotch brite.
2) Attach the neck to the body and complete the neck carving.
3) Remove the neck and begin pore fill of the neck with z-poxy.
4) Once neck is pore filled begin to spray finish on both body and neck.

I have an Earlex HVLP and plan to spray General Finishes Enduro-Var Gloss.

My questions:

1) Do folks typically go ahead and final attach the neck including gluing the FB extension on before spraying finish? It seems like it would be required, otherwise I would have to take finish off in the area of the extension, or mask it off like the bridge? I've seen some pics of folks spraying separately, which is what is confusing me.

2) Any tips for spraying if you have used this or similar setup before? I don't know what I'm worrying about with the finish, worst case I just sand it back off. It's the mental paralysis that's killing me.

So close, yet so far away!

Thanks!
Brad

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Many builders, myself included, spray necks and bodies separately. This makes repair work easier in the future if it is needed. You will need a method of removing finish from the tongue area of the top as well as from the bridge footprint. I route it off, some mask. A search will reveal some good discussions on this.

I spray nitro using standard equipment so I can't help you there.

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It will probably be alright.

Its important that you do not sand off all the Zpoxy leave a film on the entire surface otherwise there will be witness lines and/or blotches.

I am in favor of masking off the bridge and extension areas. Work the neck and body separately as done by most high efficiency makers. If you fasten down the extension it only need to be tack glued.

here's how to make a bridge mask:

http://www.kennethmichaelguitars.com/bridgemask.html

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Ken Cierp

http://www.kennethmichaelguitars.com/

Thanks for the link, that seems simple enough!

After spraying, you take the mask off and score around the actual bridge to do the final fit?

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The mask is made a tiny bit smaller than the bridge footprint. use a very sharp Exacto knife to fracture the finish at the mask edge so it peels cleanly - DO NOT cut into the wood surface. Prepare the bridge by sanding a tiny bevel around the perimeter so it clears the finish layer. Actually there are threads explaining how to make a cool tool to route this ledge.

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Ken Cierp

http://www.kennethmichaelguitars.com/

Reality check. As a new builder you need to come to grips with this fact... A guitar in the white is half done.
Half

Think of all the time you put into the build so far.
There is still that much time left to the first chords from your beautiful creation.

This is a labor of love. It becomes an obsession.

But if you resolve yourself to doing it right, then you need to put in the time.

Sorry to say, but reality is what it is.

We will help you all along the way, but you gots a ways to go.

And that my friend is why the beginners get bogged down. Finishing is its own skill set that doesn't get addressed nearly enough in the reference manuals.

Stay the course. It's worth it.

dl

Surface prep does take me a few hours, I've come to do the entire sanding process at least two times with a wait period between sessions -- but my actual process time to apply, level and polish a "gloss" finish is less than four hours. Dave you are scaring the pants off us -- what process are you using?


Now I am one of the lucky ones -- I'm enamored by George Lowden's guitars so I have come to really like the satin finishes. So my total finishing time is a little less. On occasion I will apply high gloss French polish to the sound-board.

My grandson in law is building a guitar here in the shop and we are going to use TruOil -- this is a first for me but I have seen really nice results. I am told the entire process can be completed in three days.

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Ken Cierp

http://www.kennethmichaelguitars.com/

Ken,
I should've specified I was talking about a high-gloss professional level nitrocellulose lacquer perfect finish.
D

Ken, I'm sure it's starting to feel like you are building this guitar for me. I can't thank you enough for the valuable advice. I re-read your post and this stuck out to me. The emphasis on if. Is it common to not glue this down at all?

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Ken can give his opinion as well, but mine is that it depends on the top bracing. If there's a lot of bracing stiffness between the headblock and upper transverse brace (A-frame or headblock extension) then the fingerboard extension can be tack glued or even bolted down. If using old fashioned bracing patterns with nothing or only a popsicle brace between the headblock and UTB, then the fingerboard extension functions as a brace, and should be glued reasonably well. Probably just two lines along the edges would do it, and still be easier to pull up later than a full joint. Use hide glue for this and the bridge, for its repair-friendly properties.

Super good feedback there, Dennis. Thanks!

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Brad -- A few things come into play with my design. The necks are bolt on, the neck blocks are over size in comparison to most and the mounting holes are slotted to allow vertical adjustment. What I have found is that the fretting process tends to impart a slight downward bow on the fingerboard extension. When the neck is bolted to the body slight clamping pressure flattens out the extension. We use Allen head cap screws with a flat washer and a bellville washer, surprisingly little torque is needed to keep the Bellville washers compressed tight holding the neck in place. And the flattened extension has nowhere to go as it is compressed on top the over size neck/head block. I know there is concern for bridge-ward creep of the fingerboard but I have never seen this happen. No I do not glue down the extension -- others do.

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Ken Cierp

http://www.kennethmichaelguitars.com/