Jump to content

Finishing Padauk W/o Excessively Darkening


j. pierce

Recommended Posts

I'm working on a couple of builds with padauk tops. I'm using System Three epoxy for grain fill and KTM-9 for my finish. I've done this enough times that I thought I knew what to expect - the KTM-9 alone pretty much makes the wood look the same as when it is wetted, if using the System Three it generally darkens it just a touch more, but all in all it looks like what I get if I wipe down with naphtha or alcohol or whatever.

Well, at least, that's what all my experiences have shown me . . .

Stupidly, I jumped in on these guitars without testing on scrap. Dumb mistake, and my fault. After sanding, the wood had taken on a rather bright orange colour, and wetted, it was fairly red and pretty vibrant. I laid down the Syste Three epoxy today, and the colour became *much* darker than I had expected - almost burgundy, like the finish on Gibson SGs. It's not bad - just certainly not what I was expecting. I'm still debating whether to run with it or sand it down and start over.

So I've never worked with paduak, really. Is this common? If I decide I want to have another go, I'll be practicing on scrap before I even begin to sand this down, but I'm wondering if I'm going to find similar results using shellac or something else as a grain fill, or if I get past that stage without excessively darkening the wood I'm just going to find out that my finish will darken it this much as well. Are there precautions I need to take to avoid this?

Link to comment
Share on other sites

Sand it off and try the KTM-9 by itself, and see if you get the same effect. System 3 is about the clearest epoxy that I know of.

Either way, you will not be able to preserve that bright orange color you get out of freshly sanded padauk, it will always darken to a red tone and the longer it is exposed to sunlight (UV), the more brown it will become.

Link to comment
Share on other sites

I've worked with Padauk a lot and by nature it will become a very dark red (almost brownish) on it's own. When it comes into my shop it's usually really dark and when I plane and join it the wood becomes bright red again. If I let it go too long it gets dark again.

I'm not sure if it will stay the color it is when finished or if UV will darken it (like purpleheart.) I generally use oil finishes on my guitars and Padauk gets darker over time with oil.

Link to comment
Share on other sites

In glancing over some padauk information, I read some information off a wood flooring site that mentioned oil based finished accelerating the color change from orange to dark brown(over years and years time). Whereas they say waterbase finished inhibit this change. Uncertain of whether this is factual or not, but some of their information was linked to the US forest products laboratory technical information which contains a great amount of wood related information. Anyhow, something to think about.

I've been messing with a few different finishing items on my scrap recently. Do you have any sealer(sanding sealer)? I've been messing with the zinsser sealcoat(sanding sealer) it's like a 2lb. shellac cut and while I've heard nothing but bad things about regular shellac in a can, there doesn't seem to be any or many problems with this one at least as a sealer. Anyhow, with a very light coat my scrap stayed fairly light, I believe lighter than the epoxy, though I just bought some new epoxy I need to try on this scrap. Anyhow, I'm wondering if you tried sealing lightly first, if this would prevent the epoxy (or at least some) from really soaking in deeply and instead just sit in the pores. If you so, you might be able to get a lighter finish this way.

From what I've read, shellac is a great item to use when you have finishes that don't mix, kinda of protection layer between coats. So maybe it could prevent the epoxy from soaking into the wood and darkening it and instead just fill the open pores that the shellac didn't. I'll try it this week, shellac, scratch, epoxy and then I'll compare to one with just epoxy and see. I'm sure this has been done before, but I enjoy messing around and learning. Well, best of luck. J

Edited by jmrentis
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...