Mahogany door turned black!

[Earl Johnson 14]

I stripped a mahogany door that had tung oil with a top coat of polyurethyne with HD-80, then nutralized it. I applied a coat of gold Ready Seal on it and it looked great, until the next day. In a few places the wood turned almost black. The rest of the door looks good but the black has to go. Any ideas what caused this and what to do about it? I don't want to strip the whole door if I can help it. ( It also includes two panels). Any way to lighten these dark places? Have to go back the first of the week and do something, so I need some good advice! As always, thanks for any help. Earl

[ron p 500]

i would think that the tung oil was deeper into the wood then the hd80 could penatrate. Then you removed the poly, which acted as a airtight sealer over the oil. Now the oil mixed with the ready seal and turned black.

Ill bet your going to have to re-do this job.

[Everett Abrams 501]

Earl,

It has been found that in some cases of hardwoods that the tannins will react with the oils in an oil-based product. This will cause the black spots you have mentioned. I have had the same problem on a door and the same thing occured. I sanded it and it looked great and even, applied marine varnish and looked great. Came back the next day and I was sick to my stomach. There are products out there that you apply to the surface first to block this occurance and leave the end result looking even and right. You find these products at any boat or marina store. The product I used was from Zinnser but there are other stain blockers other than that. This is common used product when refinishing boat surfaces. Unfortunately, you'll have to restrip and neutralize again. If you would like e-mail me and I'll give more detailed info

eabrams@deckrestorationplus.com

[Beth n Rod 1,279]

I agree. You'll have to redo this one. Cabot makes a product for hard wood that we have used on Ipe and teak, and you might want to check its use on mahogany.

Beth

[Earl Johnson 14]

This door is hand made and leaks bad if water pressure is put on it. I stripped it with HD-80 and P/W it off. IS there another way of stripping without using the pressure?

[James 624]

Was the door still wet when you nuet. ? Before you do anything take nuet, and rub it on if the black goes away its tannins. otherwise its forth down and you lost.... After strripping Cedar, mohg ,redwood ect it's best to wait until the wood is almost dry before nuetr alization. You can't use stain blockers if you use ready seal or anyother penitrating sealers

[Earl Johnson 14]

Thanks, I'm going back today and try the nutralizer and I'll wait befor I put it on if I strip it, which I'll probably have to do. I don't look at it as losing, just learning! thanks again I'm going to try and post pics tonight. Earl

[Earl 14]

I stripped it today because the acid didnt touch it

[Earl 14]

Edited at users request...

Beth

[Earl 14]

Don't know what I did wrong, but feel free to change the picture. It posted fine in the photo gallery (wood restoration) if anybody cares to look and tell me why it's black. Earl

[Beth n Rod 1,279]

Fixed at your request...

[Earl 14]

Any ideas as to what went wrong anybody?

[Beth n Rod 1,279]

What happened after you went back out there the other day? Do you have any new news or any new photos?

Beth:dunno:

[Earl 14]

Restripped and nutralized and it turned out about the same other than now in some places the wood has turned almost orange! the black is still there althiugh I used some bleach that lightened it some what, but looks washed out. Going back today. I''ll take another picture

[Beth n Rod 1,279]

Sounds like you are pulling the tannin or sugars out when you neutralize if the wood is lightening that much.

Need to see another more current photo...the rest would be speculation, and you don't need that.

Mahogany is a very dark wood naturally. How does the owner feel about the door right now? That's the most important question.

Beth

[Earl 14]

My arm is about to fall off. Sanded all day.....lol..........Well, it looks pretty good now . The dark wood has lightened somewhat but I don't know what it will do with the Austrailian timber oil on it. It is some werd wood! I'm not so sure its Mahogany........Its some hard stuff to sand and the dust is more like a wet dust. You have to wipe it off. Clogs up the paper, but the wood is like 10/12 % moisture content. Darnedest stuff I've ever seen. The orange sanded out for the most part. and whats left is a almost shinny semi-slick redish finish. Forgot to take a photo, try to get one tommorow. The customer is very nice and patient so thats not a problem. I'm still not sure what happened though. And I'm not sure the black wont come back. Waiting for the oil to come in, and will seal it Wed......... .Stay tuned......

[Beth n Rod 1,279]

Are you sure you aren't working on Walnut? There is a black walnut as well, and you could have a combination....I wish I could see the whole door.

[Earl 14]

I'll get a picture tomorrow....What about the defelting pads?

[ron p 500]

maybe it's not the wood?

What your describing is failed SIKKEN'S.

[sIKKENS is a brand of sealer for those that dont know]

sikkens will turn orange

sikken's will stay gooey

it will clog sandpaper.

sikken's will leave a shinny oil if not stripped a second time after sanding.

hey i could be way off here but maybe not.

the left over sikken's would look black when you tried to seal over it.

Anyone have a opinion of my blind guess?

[Earl 14]

Thats a GOOD posibilty!!!!!!!! I was told it was tung oil with a top coat of poly, but now that you said Sikkens I'm not so sure you're not right . I've only seen the stuff on a log house a few years ago and it did look real simular to this mess!! Only thing, I ended up stripping it twice and it still sands bad and hard and not really gooey, but kinda like its damp. If I had of known I would be in this mess I would have taken a before pic.

[ron p 500]

hey!!!!!!!!!!!!! i might have got one right.

[Beth n Rod 1,279]

Still looking for good supplier. The last one called back and said he can't get them.

[James 624]

I did a 500 sqft cedar deck this year. I quoted 1600.00 to strip. I did a test spot I thought I was going to make a killing. It took 30 hours. I figured there to be 4 coats of poly, sikkin or glue. Had to use a porter and cable tungsten carbide paint remover. Then sand! That was after 15 hours of strong, stronger and the strongest chemicials. Then sanding which also failed.

I told the cust. this was not biz anymore but a hobby. I'll be back tommmorow.......

[Earl 14]

but cant post it. TOO big......HELP BETH!! I want you to see this picture and maybe someone can tell me what this door from H--- is...............!!!

[Beth n Rod 1,279]

open the photo in you photo editor on your PC. Then look for a feature thea says something along the line of reduce or adjust Image Size or edit image size. Make sure the proportions are "constrained", and then reduce the image size... If it is under 2mb you can email it to me and I can fix it.

Beth

[Earl 14]

I hope it posted.