Mahogany Filled....not!

[Mr Real Nice]

Wow, I couldn't believe I actually started seeing grain show up a few weeks after I finished my body.  I sealed it with 4 coats of sealer, sprayed a catalyzed primer and used poly paint.  I'll post pics when I get home later.  Is this unusual?  I don't really mind it, but I'm just curious.

 

[jackthehack]

You don't mention filling the body? I only use lacquer; leaving stain/toner out of the picture, it's filler -> nitro sanding sealer -> nitro lacquer top coats. If the body isn't completely filled, and you often can't tell by calibrated eyeball, I always discover this by shrinkage of the nitro sanding sealer into the pores at that step. This usually happens every time I work with mahogany and requires an additional clear fill.

I'm just surprised you didn't see this until a few weeks later, although with nitro lacquer you can get a similar effect some weeks/months later as the sealer/lacquer coats continue to cure.

I've "fixed" this issue and some other finishing flaws not apparent until later by refilling with clear StewMac filler, leveling, shooting more nitro gloss and leveling again after a few weeks of cure; don't work with your materials, but would think that would work for you as well.

Those tiny little mahogany pores are very deceiving in their ability to suck up finish.

 

[Mr Real Nice]

Whoops, I meant filler, not sealer.  I used the Lawrence-McFadden fililer from stew-mac then used the catalyzed primer as a sealer.

 

[-CB-]

If its any consolation, even Warmoth finsihed bodies show grain after a while.

There are some tricks here.

First of all - humidity will run you nuts, because wood swells a LOT with humidity, and filler swells at a different rate.  The humidity you finish at should be close to how the item will be stored and used.

Then there's the filler itself - these sometimes take forever and a day to shrink in  - just like lacquer.  They can shrink under your applied finish too.

Ditto - "sealer"

And finally, even your catalyzed finish will shrink with time.  If you applied it well, you can level it and rebuff and not look back.... except I'd wait a good long time before doing that, so you dont continue to get shrinkdown.

Three bodies I had Warmoth finish for me, two mahogany, one maple, but all three show shrink in after just a year or so.

 

[jackthehack]

I don't have that many factory finished Warmoth bodies, usually DIY, don't see any shrinkage on my Spalt Maple/Alder body - wouldn't expect to really - nor on my all Black Korina VIP. A couple of the lacquer finishes I did sure do after a year, especially the mahogany.

 

[Mr Real Nice]

Good info, guys, thanks.  I'm just glad I'm not that much of a perfectionist, otherwise I'd probably blow my brains out after the time and money I put into it. 

 

[rahimiiii]

The only way you're gonna have body that shows NO grain is to have a body made of plastic (or wood coated in thick layers of plastic) then paint it... a lot of factory guitars shows grain and they use poly and stuff. Perhaps a lot of cheap beginner guitar has a shiny finish all the time because they use basswood (which has no open pore to speak of) and 1/8 thick polyester undercoat. Even my alder guitars that are painted solid shows grains after a while... just nothing I can do about it unless I dunk the body in thick layers of plastic.

Don't be surprised to find many old Fenders made from ash showing sunken grain... Gibsons have this problem as well.