Use a card scraper or scraper plane and there will be no need to sand. If you plan to get down past all the oil that's soaked in, you may need to plane it first (i'd use a hand plane) and test it on an extra piece if you have one. It may be deeper than you think.

 

Lots of boiling hot water and scrub brush, let dry, repeat a few times?

 

Don W, that's what I feel like. I tried the card scraper and the goo just keeps coming. In fact, I left the project for a while and came back to some of the grime was actually slightly oozing out from between the boards.

 

You could try going at it with a low angle block plane or jack plane, I have used one to flatten end grain cutting boards and it worked pretty well and removed material quickly. My other suggestion would be to make a router sled/flattening jig, there are some good examples if you search.

 

I think I might be taking you guys down the wrong path. The table top is flat. It's the grime/oil that I have to remove.

I don't even know what to call it. It's not liquid oil, not runny at all. It's not a hard crust like years of dried food…that's already off. It's just a sticky grime that want off before I put a few nice coats of butcher block oil on top. It even discolors the wood a little.

Although as I'm writing this maybe taking of a thin layer of wood would get me down to nice material. Unless as Don W says, the grime goes deep???

 

I would try a heat gun. Warm it well then wipe it down then repeat. Or put it in a black plastic bag in the sun and let the sun heat it.

 

boiling water, heat guns, plastic bags…..hmm, I would be leary. The block IS glued together. Plane that baby down, you may have to go 1/4" maybe more. You have years of muck, be thankful you did not eat at that cafeteria. Does the block smell bad, like rancid?

 

power washing isnt a bad idea, is it end grain or side grain?

Im curious to see it, could you post a picture?

 

Not too much water. I've done what you're doing. Get some lemons. Depending on how bad the top is, you might need a whole bag. Get some salt. Kosher salt is bigger grains and will last longer for what you're going to do, but once it gets pretty clean, you can switch to table salt.

Cut lemons in half. Scrub the top with the lemons. The acidity helps cut the grease. This is more acid than vinegar. Let the lemons squish and the lemon peels become part of the process.
Add a handful of Kosher salt and keep scrubbing with the lemons and salt. On a 3×4 board, if you have half a dozen lemons involved at this point you're about right. Add more salt. As the lemons break down and become pretty useless, wipe them away and keep going with the salt. When you either A.) get tired or B.) it's starting to look much better…. wipe it all off. Give it a quick rinse with hot water and DRY IT immediately.

Do NOT soak the board with water. Lots of elbow grease to recover a block that came out of an institutional setting, but I've recovered several and they can be really fine. If it's a tight-grained board, the grease and oil is not locked into it too badly.

If you want to go faster, you can spend some money to get Citrus Solvent. It's made entirely from citrus and has no petroleum distillates in it at all. It is 98% citrus oil and 2% water. VERY safe, but not cheap. I only get mine from realmilkpaint.com

Don't get Citri-Solve or Citrus Solv… you need the real thing.

The only thing you do by applying heat is to thin the oil/grease and unless you have a plan for absorbing it once you've done that, it doesn't really help you.

 

Are you sure you want to use it? Sounds like it could contain a lot of bacteria. You need to get to pure wood. Do you know someone who has a band mill that could cut about 1/4"- 1/2" off it if stood on its side

 

+1 Charlie.

 

Jim, WI.U. did a study and found that bacteria will not survive on or in wood cutting boards.

 

scraper

or - sanding disk or wire wheel in an angle grinder (very messy though as it will throw all that grime all over the place - but much faster than any other sanding medium)

 

I'm wondering how a hot iron with paper bag paper between the wood and iron would do. This is a method of soaking up wax. The paper would soak up the heated oils.

 

When you apply heat, you only THIN the oils, but you also expand the wood's cells and as they expand…. they PULL the oils IN. You don't want to force the wood to lock in the oils. You're trying to get them out.

And once you get the board clean…. YOU OIL IT! HAhahahhaa….. seems kinda fruitless, doesn't it?

 

Let's see some oily, sludgy butcher block pictures!

 

Winner! Winner! Chicken Dinner! Charlie's advice proved to work the best. The lemons and salt cut right through the grime. It took a little time, used about 8 lemons, and it turned out pretty cool. I did follow each "coating" with some card scraper work, so Don W's advice was right on as well. In the end, I think it looks awesome. I didn't want a perfectly milled, pristine butcher block. This look still has enough of the worn look, without being abused.

Here's the before:

And here's after the cleaning and scraping:

This is going on top of a black cabinet, the whole thing will get heavy-duty wheels and it will be set the same height as our counter top.

Thanks for all the help!

 

Excellent.

So basically you tanned it then planed it. Cool.

 

I assume the county shut down that cafeteria. That block WAS disgusting. Nice job on the after. As soon as I saw Charlie's response I knew it was the way to go. Congratulations, job well done.

 

Nice job. I love the old boards. Lots of patina. Lots of history. People look at me like I'm from Mars when I tell them not to use water and to use lemons and salt on a really nasty looking board.

Let that baby dry a couple days ON EDGE. Don't lay it flat or it'll dry on top too fast. If you raise it up 4 to 6 inches sitting on pointy blocks or something, it can be flat. Just want it to dry evenly or it'll warp or crack.

Once it's really dry, rub it with mineral oil. First time, lay it on heavy and wait about 20 minutes before wiping off the excess. Top and bottom. Mineral oil will NOT go rancid and stink. If the board smells like rancid oil after you use the mineral oil, give it a salt scrub (no need for the lemons at this point) with just enough water to make the salt a little pasty. You can use a few drops of mineral oil in place of the water. Wipe off the salt. Wipe the board with a damp rag or sponge…. damp… not wet. Let it dry… mineral oil again.

Once you get the board oiled with mineral oil, you only need to re-oil it when it looks dry. You'll know. It will look "too white". I use a microfiber cloth for oiling my boards and just keep it in a zip-loc bag in the cabinet with a little squeeze bottle of mineral oil.

 

Have to favorite this post for all the good info.

 

That's some valuable information being passed on right there. Great board and great advice from Charlie. Good stuff fella's, that's what this is all about!

 

Here's the final island. The black piece was already there. I just replaced the top, added the locking wheels and made it the same height as our counter tops.

Thanks again for all your help!

 

Much much better!!

 

Some take-away points from this thread and Charlie's great advice:

1) Wet-dry cycling is one of wood's worst enemies; it causes expansion, then contraction, then splitting/warping.
2) Rapid heat cycling can yield similar problems as wet-dry cycling.
3) Heat helps the wood take up more oil-good choice to not use heat in your efforts to remove the gunk.
4) Tung oil is very good for block tops and salad bowls. After drying, it becomes non-toxic. I use General Finish's Seal-a-Cell.
5) For similar challenges, like old penetrating stain finishes, I have simply flipped the piece over and properly finished the backside for use as the front side.
6) Citrus-based "block oils" are good alternatives to mineral oil. I have mixed feelings about mineral oil due to its mineral (i.e., petroleum) based origin. There is a very good chance that your block tops got all funky like that from the use of mineral oil, rather than lemon oil, because it is more resistant to food-prep area type cleaning products.