Weird finishing problem

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old_picker
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Weird finishing problem

Post by old_picker » Wed Mar 06, 2019 5:48 pm

Got this infuriating issue with a maple one piece neck I have just re-fretted. I used titebond liquid hide glue to help the frets stay put and as usual residue got on the board which cleaned up nicely with a wet then dry rag. Started using the hide glue several years ago with refrets. Not sure I have used it on a maple board before this though.

I am attempting to spray mirotone 3220 satin over the fingerboard and it is not sticking well. Some small spots are bare and it sort of looks like the surface is repelling the lacquer. Ive cleaned the lacquer off twice so far with superglow multi thinners, sanded with 400 and retried. Shot 100's of maple boards and necks and never seen this before.

After pulling the frets I leveled and sanded it to bare wood all over the board and masked the poly on the other surfaces as I usually do. Generally get a great colour match. In a situation like this I'll look for the culprit in things I have done different to normal.
Same surface prep routine 180, 240, 400. Laquer from the same batch from the pot on the gun I shot multiple coats onto a body from two days earlier.

the only thing different is that I have used is a foreign masking tape from Tenacious tapes [K750]. A lemon colour with a kind of waxy feel to it. Wondering whether this could be the culprit? Not sure though how it could get onto the wood all over the fingerboard though. Maybe a chemical is emanating from the tape? It is not worse at the edges and looks to be pretty general right over the board. Oh and of course the liquid hide glue. I wouldnt have thought something that sticks to wood so well could repel lacquer.

As I've said I've cleaned the lacquer off twice with superglow thinners and sanded lightly scuffed with 400 - cant really bite into it much as the frets are down and I aint pulling them up. Ideally I should be able to clean up any residue with some kind of solvent. obviously superglow multi thinners is not doing it. BTW I've used this stuff to strip mirotone 3220 off quite a few necks over the years with never a problem

It is infuriating as this job should be pretty much done by now.
Any one have a suggestion or seen a similar problem with a solution? - hopefully someone can shed a little light.

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Trevor Gore
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Re: Weird finishing problem

Post by Trevor Gore » Wed Mar 06, 2019 6:27 pm

Check with Tenacious Tapes whether or not K 750 contains silicones. Some tapes do and that would explain things.

old_picker
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Re: Weird finishing problem

Post by old_picker » Wed Mar 06, 2019 6:39 pm

How would silicone be successfully removed?

old_picker
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Re: Weird finishing problem

Post by old_picker » Wed Mar 06, 2019 8:12 pm

this is the tape
https://www.directpaint.com.au/tenaciou ... -tape.html

The Blurb -
Well defined edge with no bleed through on smooth surfaces
Strips cleanly & easily without leaving a residue
Ideal for two pack paints, automotive & marine applications
60 Days + Outdoors

Image

old_picker
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Re: Weird finishing problem

Post by old_picker » Thu Mar 07, 2019 11:30 am

Posting to myself here except for Trevors contribution - Thanks -
This is informational for any one in the future having lacquer adhesion problems.

I can say definitively that Tenacious Flowmask K750 is NOT the culprit in this case. Conducted an empirical test using the tape this morning. The smooth side of the roll was rubbed vigorously over a piece of fine sanded timber about 150mm x 100mm area. I then stuck a 70mm length of the tape on the board. The tape is 24mm wide. Then shot two rather heavy wet coats of the same lacquer over the lot allowing drying time in between. The lacquer bonded to both timber and tape as would would expect with standard crepe masking tape. None of the problems seen on the neck were at all evident. I have wiped a few mils of the titebond liquid hide glue over a section of the same board and will conduct a similar lacquer test when it dries.

Solvents such as acetone, methylated spirits, lighter fluid and vinegar show up in research around the web this morning as likely supsects for removing the offending residue - whatever it is. Thankfully it is not silicone from the tape. It may be that there was something on the sponges I used to wipe down glue squeeze out as I punched the in frets.

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rocket
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Re: Weird finishing problem

Post by rocket » Thu Mar 07, 2019 3:53 pm

Sorry I didn’t have anything to add there Picker but thanks for posting, I hope you can get that job off the bench now!

Rod.
Like I said before the crash, " Hit the bloody thing, it won't hit ya back

www.octiganguitars.com

Mr K
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Re: Weird finishing problem

Post by Mr K » Thu Mar 07, 2019 8:19 pm

Hi Ray, I'm no expert, I see that it's a re fret so I assume the guitar is a clients. Is it possible that they have used a polish containing silicone?
I remember way back when you could add Anti Silicone drops to the paint to aid in levelling not real sure of this approach today , maybe someone with better spraying knowledge than I can help.

Cheers Mark

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kiwigeo
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Re: Weird finishing problem

Post by kiwigeo » Thu Mar 07, 2019 9:28 pm

Mr K wrote:
Thu Mar 07, 2019 8:19 pm
Hi Ray, I'm no expert, I see that it's a re fret so I assume the guitar is a clients. Is it possible that they have used a polish containing silicone?
My thoughts as well.
Martin

Dave M
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Re: Weird finishing problem

Post by Dave M » Fri Mar 08, 2019 4:20 am

Wouldn't a couple of coats of shellac seal whatever the problem is?
------------------
Dave

old_picker
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Re: Weird finishing problem

Post by old_picker » Thu Mar 14, 2019 2:43 pm

Thanks for the replies on this one - never thought of using shellac - I have a nice fresh batch I made up a couple of weeks ago :)
Also it could be likely silicone polish was used by the owner but I don't want the cat out of the bag just yet. Some of the problem areas seem to be along the frets and I am thinking maybe some type of machine oil on them. They are dunlops. I've used stewmac wire on maple boards before and never problems like this.

Not the Titebond liquid hide glue either as I smeared a pretty solid area with it and after it set I piled the finish over it. No adhesion problems. Yesterday I sanded the whole board with 400 and started in with fresh lacquer and still the same - maybe not as bad.

I'm going to strip the finish off again and try some shellac over the worst area [nut to first fret] and see how it sticks. I too a couple of snaps that show the problem off pretty good.

More soon and hopefully a result

Image

Image

old_picker
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Re: Weird finishing problem

Post by old_picker » Fri Mar 15, 2019 10:06 am

It looks like I got this one beaten with the help of forum members and in particular DaveM who nailed it with the shellac suggestion. Initial test from the nut to the 4th fret is very encouraging with no pull back evident in the shellac.

It is my standard mix. whatever cut that is, I use as a seal and fill for under mirotone 3220. A jar about half full of dewaxed flakes just covered in metho. After a couple of days all is disolved and add metho till the quantity is roughly double the quantity and a little more. Very scientific approach.

I digress though and it seems what I have seen and read that nitro will stick to pretty much anything is incorrect but shellac sure does.

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