Search results for query: oxalic acid

...My plan to fix this is: - Plane all varnish and grey spots with the electric hand planer - Sand everything down to 240 grit - Apply Oxalic acid to bleach the wood - Apply yacht varnish again but this time first two coats will be diluted for better tack Can anyone recommend is this good plan...

I would try oxalic acid as a first step. if it does bleach out the stain it should be permanent. Mix up a strong solution of oxalic with boiling water (you will need good thick rubber gloves) using a nylon pad spread the oxalic over the entire board and then with a firm pressure concentrate on...

...flake of rust, a particle of steel, or the metal part of a cramp or tool, has touched the wet timber around the glue joint? The traditional solution, Oxalic Acid, has fallen out of favour on health and safety grounds, and certainly isn't appropriate for a toy chest. First option is a card...

When I first started woodworking Oxalic Acid was widely used, for example if Oak components touched sash cramps during a glue up they'd likely stain and so you'd do a spot application of Oxalic Acid to cure the problem. You might wear gloves, I can't ever remember anyone using masks, and you'd...

...oak, and you used water for the clean-up, the blue is more likely to be iron staining which can happen very easily with oak, just from little specks of iron floating around in the air or on a not very clean rag. If it is, the marks should come out with oxalic acid, which is sold as wood-bleacher.

You could start messing around with Oxalic Acid, but it's just not worth it. For one thing you'll only affect the fraction of a mill right at the very surface, so the work has to be done on the finished piece or finished component, that makes it too risky if it doesn't work out as by then you've...

...there is, wax, and all varnishes and lacquers. In fact, I'd go so far as to say you are better off leaving the wood unfinished so that if some wet plaster finds its way past the tape you will have a chance of scraping off a layer, or using some oxalic acid, to remove the resulting black stain.

Thanks for quick replies. I'll get hold of some oxalic acid and give that a try I think as I only need to change the appearance of the top surface of the wood. The last 100mm of the piece of oak is to be trimmed off so i can do a tester on that and see what happens. Failing that its time to...

...explain to the customer that trying to unify the look will be impossible especially if it's going to have a clear coat; that even should oxalic acid work which is the normal method for such things - there will still be a colour differential, and there will be a time factor to add to the cost...

...and rain for a few months! Now, I understand that I can revive the wood with something like Osmo 6609 Wood Reviver, which appears to be Oxalic Acid in a gel formulation. But how do I finish the wood after revival? The surface is still going to be reasonably rough so something with a good...

Oxalic Acid is unlikely to be the solution you need, the sun darkened patch will have a slightly soft edge that would be very difficult to align to, the timber will have experienced a colour shift that Oxalic Acid won't match, and the degree of lightening you'll achieve isn't controllable so...

...I confront this problem all the time. I use a lot of American Cherry which acquires a suntan in double quick time. Just laying out the components during the course of a build will often see "bikini lines" here and there. So when I say Oxalic Acid isn't helpful I'm talking from bitter experience!

...Liberon product linked to above pay careful attention to the usage instruction, this type of wood bleach is a concentrated solution of oxalic acid which is toxic. It's quite safe when wet as long as common-sense precautions are taken but after it dries it turns into a powder and you want to...

It isn't clear how much, if any, rinsing was done initially. Could you describe how you washed off the surface after bleaching? Oxalic acid needs to be rinsed very thoroughly from wood so as not to cause problems with subsequent finishes. With wood that can't have flowing water run over it you...

...to flush or wipe down with plenty of clean water afterwards to get rid of it. If it is iron staining as peter-harrison suggests then oxalic acid will treat it. Even jet-black old stains from rust can be brought down so it should have no trouble at all with this. Again you just need to flush...

Scrub with sugar soap, rinse and dry. If there is staining maybe move on to oxalic acid. Then deal with any raised grain.

Oxalic acid cleans up oak quite well. Either buy pre-prepared as wood bleach or buy bulk crystals online.

" Oxalic Acid is the thing to use " Yep, sure is :)

Apparently, Oxalic Acid is the thing to use ... ??? Edit ... SNAP!!!

You could use oxalic acid. But be careful to wash it off before sanding as tjhe dust can be nasty. Chris