Dealing with Pre-Stain and Wood Conditioner Residue

Question

I'm currently working on staining a 10' walnut butcher block counter:

I have done a lot to get everything together:

• Surface prep: sand at 320 grit using orbital, wipe using rubbing alcohol to remove wood dust, repeat until smooth.
• Pre-stain wood conditioner: stir well, apply using foam brush, wipe using dry rag to remove excess, wait a few minutes, wipe with wet rag, wipe with dry rag.
• Sand after pre-stain at 320 grit using orbital

Unfortunately, something really awful happened when I started sanding after conditioning:

Apparently some of the wood conditioner was left over, and turned into this tough syrupy residue, and sanding it simply spread it out and hardened it, leaving chunks of it all over the counter. To remove it, I had to sand and wipe with rubbing alcohol many, many times.

When I did the pre-stain on the other side, I was careful to wipe away all the excess and really make sure that nothing remained on the surface. I also hand-sanded with a 240 hand sanding sponge, wiped with rubbing alcohol, and then went to sand with my orbital at 320.

The hand sanding did not reveal any gunk, so I felt that I could proceed with the orbital. Unfortunately, yet again, gunk was left over, and I found this stuff on my sanding pad and on the counter surface again.

I'm going to work on removing this stuff using the sand/rub loop again today, and then the next goal is to actually apply the stain. I fear that I might run into the same issue with the stain.

What did I do wrong here? And what can I do better to avoid this while applying the actual stain?

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EDIT

This is the pre-stain, stain, and seal (not in order pictured) that I was planning on using:

It seems that:

1. I didn't need to spend a couple days using pre-stain because I'm working with walnut.
2. The high speed of the sander caused the conditioner to heat up and build residue.

Between applying the pre-stain to the bottom of the counter and sanding, I waited 48 hours. Between the pre-stain application to the top and sanding, I waited 20 minutes as per the instructions on the can.

I have made an Imgur album with pictures of the labels on the various items.

Since I appear to have gotten a lot wrong here, I'm not sure how to proceed. I can clean up the rest of the wood conditioner with alcohol and sanding, and I am not sure what to do next.

• If I should use a lower grit sandpaper, what grit should I use? I have everything from 40 to 320.
• Should I use the lower grit to prepare the surface for staining?
• Should I obtain and use mineral spirits instead of rubbing alcohol for clean-up?

I'm feeling a bit shaken as I did a fair bit of research on this, and this project in particular has taken a very long time to realize. Surface prep on one side to 320 was accomplished with three passes; surface prep on the other side took around 10 passes; cleaning up the residue took probably around 5 passes; hopefully cleaning the top will be easier.

My goal is a dark walnut shade and a satin finish, definitely not glossy.

Thank you for being such a welcoming community!

Answer 1

OK first off, hate to break it to you but you could have avoided so much extra time and effort here — you didn't even need to use "pre-stain" or "wood conditioner" :-(

These are to help prevent blotching in blotch-prone woods, and walnut isn't one of those. Therefore it doesn't call for any special pre-staining preparatory steps other sanding to an appropriate grit (more on this below).

Apparently some of the wood conditioner was left over, and turned into this tough syrupy residue

Pre-stain products or "wood conditioners" are nothing more than highly-thinned finish. I think it's the case that you just didn't wait long enough for it to harden before you started power sanding. This generates significant heat from friction, so you got corning.

320 is too fine
Conventional stains require, that is they work best, when the wood is sanded more coarsely, not more finely.

The prep instructions for your stain should mention something about this if you check. And any reliable finishing guide should cover this, with examples, so you can see the differing results of sanding to an appropriate grit (which is much coarser than most people think) and sanding more finely where the wood ends up considerably lighter. The finer you sand the less colour you'll get from your stain.

As I say this is particularly with conventional stains but is true to some degree with "gel stain" as well (depending somewhat on the application method, number of coats etc.)

Answer 2

I'm sure Graphus will correct me if I'm wrong but I think your big problem is sanding after prestaining. with an oil based prestain, there is no need to sand, and a water based one, you just are 'knocking down' the grain that stands up after drying. The prestain is basically the last step before you stain.

You have all your sanding done, prestain, if it is water based a light hand sanding with a sand paper, (220 or 320) and then go into the stain. The prestain's job is to fill in pores in the wood to 'even out' the stain absorption, so all the 'gunk' you find is the prestain itself, clumping instead of being dust, probably somewhat from the heat. So less sanding will get you where you want to be.

I could be wrong but I also don't think walnut is a wood that generally needs a pre stain either. I suspect you'd probably be happy without it. But since I usually like the 'natural' look and use clear finishes... You can always try doing some of this on the bottom of the piece where it won't be seen to see if you like it.

Answer 3

As others have said, you don’t sand after pre stain wood conditioner. Totally defeats the purpose, and you just remove it. Secondly, yes, pre stain wood conditioner is typically for soft woods, it’s saved my butt on fir and pine and poplar, but it can also be used on some hard woods. I have a piece of southern walnut that is incredibly porous with a few softer areas, and pre stain conditioner was just the thing. If you put it on hardwood that doesn’t need it, you’re gaining and losing nothing, just wasting your time. Finally, after application the typical wait time before staining is about 15-30 minutes, not 1-2 days. Minwax says after 24 hours you would need to reapply it. In your case since you sanded it off, it didn’t matter how long you waited, you will still see it on your pad. Re-sand surface with a clean sanding pad, wipe with mineral spirits and wait for it to dry, then pre stain if you think you’ll have absorption problems, wait 30-40 minutes, stain. If you want light sand after staining with a water based stain.