Woodnet Forums
Blotch prevention? - Printable Version

+- Woodnet Forums (https://forums.woodnet.net)
+-- Thread: Blotch prevention? (/showthread.php?tid=7345702)

Pages: 1 2


Blotch prevention? - KingwoodFan1989 - 01-14-2019

I've been putting the finishing coats on the top of my dresser project, and I've noticed that from one end of the top, there are some very obvious and ugly blotchy areas going on (first 3 of the pictures). Other angles result in a surface that has some waviness and color variation, but looks pretty great overall and has character (the rest of the pics). I'm also not too pleased with how the grain looks from that angle...I used two different rough boards, so I had to do the best I could with what I had. I think overall the other angles look great, though, especially from the front! I guess that's what chatoyance does sometimes...

Although I'm usually a huge stickler about blotching, good views from 3 out of 4 sides is good enough for me in this case, as this has been an on and off project since October 2017. I'm ready for it to just be done, to be honest, so I don't want to sand back down to the wood and have to wait several days for the natural stain (to enhance the color before the water-based topcoat goes on) to dry (it gets down into the 40's or 30's a lot of the time here). However, as usually happens, it's good to re-finish furniture tops now and then, so for future reference, are there any products that can be applied before putting finish on? I may have asked about this topic before on here, but that was years ago if it did happen. I also know about Charles Neil's stuff, but I'm interested to hear what has been the best thing for everyone as I literally have no experience with this stuff. When this top does require re-finishing, I'd like to eliminate the blotching. For now, I'll just put the dresser at such an angle that it can't be viewed from that side.  Yes


RE: Blotch prevention? - jteneyck - 01-15-2019

What specific "natural stain" are you using?  

John


RE: Blotch prevention? - KingwoodFan1989 - 01-15-2019

(01-15-2019, 11:10 AM)jteneyck Wrote: What specific "natural stain" are you using?  

John

Minwax oil based.


RE: Blotch prevention? - jteneyck - 01-15-2019

(01-15-2019, 06:53 PM)KingwoodFan1989 Wrote: Minwax oil based.

Oils can sometimes cause blotching, and it looks like that's what's happening here. When I am concerned about blotching I turn to spraying.  I spray dye when I want to color the wood, and I spray at least the first layer of sealer or topcoat over that. By putting a uniform amount of product on the surface it doesn't blotch like can easily happen with hand applied methods.  Once the surface is sealed you can apply more color or coatings anyway you want w/o risk of blotching.    

John


RE: Blotch prevention? - KingwoodFan1989 - 01-16-2019

(01-15-2019, 08:45 PM)jteneyck Wrote: Oils can sometimes cause blotching, and it looks like that's what's happening here.  When I am concerned about blotching I turn to spraying.  I spray dye when I want to color the wood, and I spray at least the first layer of sealer or topcoat over that. By putting a uniform amount of product on the surface it doesn't blotch like can easily happen with hand applied methods.  Once the surface is sealed you can apply more color or coatings anyway you want w/o risk of blotching.    

John

I'm not trying to dye the wood a different color, though. I'm just trying to bring out the natural color a bit more, so I used the "natural" type of stain. I'm not sure I can spray oil based stain without a permit and specialized equipment...what can help enhance the natural color that you can also spray? Alternatively, how would that Charles Neil stuff work? I definitely prefer to wipe the finishes on, and that stuff looks good on video, but I'm wondering if it's meant more for colorizing stains than for just natural ones (or if it can be used for both). That or any other product that I can apply beforehand to enable me to wipe a finish on without blotching would be ideal.


RE: Blotch prevention? - jteneyck - 01-16-2019

Even natural OB stain has oil in it.  Oil can cause blotchiness and you are seeing that happen.  I have no experience with CN's blotch controller though I've read that others have liked it.  I would not use it under a natural finish but that's just my opinion and no actual experience.  

Nearly anything you apply by hand is likely to cause blotching now that you know it can happen with that tabletop.  So I would get some rattle can shellac and uniformly spray a coat or two of that.  Do not go back and add additional spray to any dull areas. Let it dry a couple of hours , gently sand it with 320 or 400 grit, and then proceed with whatever clear finish you want.  The shellac will highlight the grain in the wood and won't blotch because you sprayed it on.  

John


RE: Blotch prevention? - KingwoodFan1989 - 01-16-2019

(01-16-2019, 10:58 AM)jteneyck Wrote: Even natural OB stain has oil in it.  Oil can cause blotchiness and you are seeing that happen.  I have no experience with CN's blotch controller though I've read that others have liked it.  I would not use it under a natural finish but that's just my opinion and no actual experience.  

Nearly anything you apply by hand is likely to cause blotching now that you know it can happen with that tabletop.  So I would get some rattle can shellac and uniformly spray a coat or two of that.  Do not go back and add additional spray to any dull areas.  Let it dry a couple of hours , gently sand it with 320 or 400 grit, and then proceed with whatever clear finish you want.  The shellac will highlight the grain in the wood and won't blotch because you sprayed it on.  

John

Hmm...that shellac idea sounds like it'd be good. Heck, I might try it this time around since shellac dries A LOT faster than oil based, especially in this colder weather. Only this is, I'd have to check if the Zinsser spray-on cans have wax in them like the cans do. I know there's Seal Coat, but I'm not sure if that comes in a spray can.

I'll go to the hardware store in a bit and check!

EDIT: Weird...the spray on Shellac by them explicitly says it does not contain wax...why the heck do they do it with the wipe on stuff then? What's the benefit of it?

Either way, I'm gonna sand the top down with 240 grit until I get back to the bare wood, and unless I need to trim off a bit of each edge (in case they get too thin again), I can just spray the shellac on! Hopefully it works better than the natural stain!


RE: Blotch prevention? - Woodenfish - 01-18-2019

Spray can shellac does not contain wax. Wax would clog the tip. not my opinion but as told by Zinsser.


RE: Blotch prevention? - KC - 01-20-2019

Blotch = natural to me.

I think woodworkers as a group spend a lot of time trying to 'fix' a natural characteristic of a species.   Botch = character.   Yes


RE: Blotch prevention? - jteneyck - 01-20-2019

(01-20-2019, 09:32 AM)KC Wrote: Blotch = natural to me.

I think woodworkers as a group spend a lot of time trying to 'fix' a natural characteristic of a species.   Botch = character.   Yes

What some call character others call blotch.  Neither is right or wrong.  The OP calls it blotch, so it's blotch.  

John