When a dye job goes wrong - Terry, possibly?

[Anonymous]

Hello folks -
I'm in the process of building a snare drum. Essentially it's just a wooden cylinder, 14" diameter X 6.5" deep, of maple (it's a Keller shell, if that means anything to anyone here).

After the initial shell preparation, as detailed in my previous post entitled "Finishing information from FVF drums", I applied a purple Liberon water-based dye. I slopped too much dye on, and it dried rather patchily. So, I tried to even it up a little, by (a) sanding the heavier patches lightly with 600-grit wet/dry paper, used dry, and (b) adding more dye. Oops. Not a good idea. It's a learning process.

The upshot is, the shell looks worse than it did, IMO. Alas, my digital camera is in for repair so I can't take a pic to show you.

I've two choices. The easy option is to buy a wrap, readily available from loads of drum wrap companies in the States, but I'd like to use this project as a sort of apprentice piece, if you like. I'd like to practice the lacquering/polishing process. I'll make my mistakes now, and not make them next time.
The other option is to disguise the poor dyeing, and this is where maybe Terry could help. Allow me to run this idea by you.

I've ordered a clear, water-based, gloss acrylic lacquer. The dye, too, is water-based. I'm not too worried now about showing the grain in the wood. If I were to add a little dye to the lacquer, to "darken down" the finish, would it affect the lacquer adversely? If it won't, I could still go through the rest of the finishing process, for practice, if nothing else.

Thoughts, anyone?

Thanks

Stephen

 

[Alf]

Stephen,

No, not the answer I'm afraid , but just to let you know Terry's on holiday at the moment (lucky blighter), so we'll have to hope for help from elsewhere. As far as I know you can add the dye to the lacquer, but whether it would solve the problem I really don't know. Anyone?

Cheers, Alf

 

[Anonymous]

OK, thanks, Alf. You folks get holidays?!!? :shock: Actually, I'm not long back from the S of France myself.

I'm not really trying to "fix" the problem now, I don't think it can be fixed as such, rather, I'm thinking of hiding the poor dyeing of the wood by dyeing the lacquer too. I'm just wary of adding dye to the lacquer and having that affect the curing/finishing process in some way.

Stephen

 

[Chris Knight]

Stephen,

Blotching is caused by the wood differentially absorbing the stain. This can be caused by variations in the wood pore structures as they intersect your surface - thus knots, end grain, grain reversals etc will all cause such variation. So too will differences in sanding. If you sanded a uniform piece of wood with different grits in stripes - each stripe would take up dye a bit differently.

You can help avoid this problem by a couple of methods - seal the wood with a light wash coat of shellac or glue size (hide glue preferred) first and then apply stain. Second method, wet the wood with the stain's solvent first ( water in your case) this will soak preferentially into the most absorbent parts of the wood that would otherwise take up too much colour and let the stain flow on more evenly.

If you are in learning mode, you could try bleaching out the stain you have applied. There are basically three types of bleach used for wood finishing and you want the chlorine type of bleach. You can make this up yourself from swimming pool chlorine powder (calcium hypochlorite) or buy it from a supplier - worth checking with Liberon who made your dye.

You should then be able to "start over"

 

[ike]

Liberon do a "Wood Bleach" based on oxalic acid although I don't know if it neutralises water based dyes.

Ike

 

[Chris Knight]

Ike,
Oxalic acid is excellent for removing the black stains caused when iron stains woods with a high tannin content like oak and cherry - it doesn't have to be metals like screws, the iron in tap water is enough so spills etc can cause them.

It is not very good for bleaching most dyes. For this a chlorine bleach is normally better.

For bleaching the wood itself, a two part oxidising bleach is used - Part A is caustic soda, Part B is Hydrogen peroxide. You can buy all these at a professional finishers suppliers like Mylands etc.

There is some overlap between the applicability of these bleaches dependent on wood species and the nature of the colour/stain to be removed so as usual, testing is needed.

 

[Keith Smith]

How about sanding the wood carefully to get a uniform smoothness then give the wood several more coats of dye to darken (and even up) the finish?

BTW I wouldn't mix dye with the laquer, if you want this to be a practice piece then you would be practicing something you will hopefully not need to do again; mixing dye and laquer you are basically making paint.

Keith

 

[Terry Smart]

Hi Stephen and all others

I knew I shouldn't have gone away!

First off, I would strongly advise against adding a water based stain to a water based lacquer as this will almost certainly have an adverse affect on the drying and performance of the lacquer.
It is quite acceptable to tint a Melamine Lacquer with our Spirit Stain so this might be an avenue to invesigate. Up to about 10% stain can be added which will only tint the lacquer and should not give a paint effect which should be obliterating.

To get back to your original problem, did you try using any solvents to remove the stain? Liberon would probably be in a better position to advise on this, but I would have thought that a cellulose thinner should shift some of the stain, certainly enough to get you back to a position where you could restain it once the thinner has dried? Perhaps time for some experimentation?

Not one of more more helpful postings (up to standard then!) but I hope this has been of some use!

Good luck!