Finishing the bench

[Nathan Callender]

Folks, I'm finishing up my roubo-esque bench and am planning to apply some Danish oil as the finish. It's big and beefy so I'm trying to talk myself out of flipping it over to finish the underside. Would finishing just the exterior surfaces be problematic? It's syp laminated top and base.

[Brian Holcombe]

No finish needed.

[Karl Andersson]

...however, if you choose to finish it, just finishing the 'external' surfaces shouldn't matter with massive structural pieces. I finished my Doug Fir bench years ago with BLO on the work surface because I wanted a little bit of finish on the soft wood to consolidate it a little and help keep it clean. I also put thinned spar varnish/ BLO mix on the legs, trestles, etc. to keep dust, moisture, and spider webs from sticking to them in my unheated outdoor work shed (it has worked). The built-up bench top was only coated on the working surface and the edges (not the underside) and it doesn't have problems with warping, seasonal movement, etc. if that's what you're worried about.

As long as the growth rings aren't all in the same orientation from board to board, I wouldn't think a laminated top or legs would be affected much seasonally -at least regarding whether some surfaces were oiled and some weren't. I'd be more concerned with solid, monolithic pieces of wood (although that might be an unfounded concern).
Karl

[Curt Putnam]

If you are going to finish the top, here are two time tested finishes that work, courtesy of a gent named Howard Acheson

This is what I recommend for a workbench top treatment. A film finish (lacquer, shellac, varnish, poly varnish) is not the way to finish a workbench top. A workbench is going to get dinged and film finishes will crack or craze or be otherwise damaged. Once a film finish is penetrated, it looses its effectiveness and adjacent areas begin to fail. No treatment is going to make a soft wood benchtop harder. I much favor an "in the wood finish". Here are two that lots of folks find effective. First, is an boiled linseed oil and wax finish. Sand the surface to 180 grit. Mix paraffin or bees wax into heated boiled linseed oil. USE A DOUBLE BOILER TO HEAT THE OIL. The ratio is not critical but about 5-6 parts of boiled linseed oil in a double boiler with one part paraffin or beeswax shaved in. Take it off the stove. Thin this mixture about 50/50 with mineral spirits to make a heavy cream like liquid. Apply this mixture to the benchtop liberally and allow to set overnight. Do it again the next day and again the following day if the top continues to absorb it. After a final overnight, lightly scrape off any excess wax and buff. This finish will minimize the absorbsion of any water and you can use a damp rag to wipe up any glue excess. Dried glue will pop right off the surface. Renewal or repair is easy. Just use a scraper to remove and hardened stuff, wipe down with mineral spirits using a 3/0 steel wool pad (a non-woven green or gray abrasive pad is better), wipe off the gunk and apply another coat of boiled linseed oil/wax mixture. My personal preference is for an oil/varnish mixture treatment. Either use Minwax Tung Oil Finish, Minwax Antique oil or a homebrew of equal parts of boiled linseed oil, your favorite varnish or poly varnish and mineral spirits. Sand the benchtop up to 180 grit. Apply the mixture heavily and keep it wet for 15-30 minutes. Wipe off any excess completely. Let it dry overnight and the next day, apply another coat using a gray non-woven abrasive pad. Let it set and then wipe off any excess. Let this dry 48-72 hours. To prevent glue from sticking apply a coat of furniture paste wax and you're done. This treatment is somewhat more protective than the wax and mineral oil as the varnish component adds some protection from not only water both some other chemicals also. The waxing makes the surface a little more impervious to water so you can wipe up any liquid adhesive. It also allows hardened adhesive to be scraped off. Repair and renewal is easy. Just go throught the same scraping, wiping down with mineral spirits and reapplication of the BLO/varnish/mineral spirits mixture and an application of paste wax. Both of the above treatments are quite protective but are easy to maintain and renew. They do not fail when the surface takes a ding.

[Chris Fournier]

I'd finish both sides. Do the bottom once the bench is assembled, no need to flip the heavy lug.

[Stanley Covington]

If you are going to finish the top, here are two time tested finishes that work, courtesy of a gent named Howard Acheson

This is what I recommend for a workbench top treatment. A film finish (lacquer, shellac, varnish, poly varnish) is not the way to finish a workbench top. A workbench is going to get dinged and film finishes will crack or craze or be otherwise damaged. Once a film finish is penetrated, it looses its effectiveness and adjacent areas begin to fail. No treatment is going to make a soft wood benchtop harder. I much favor an "in the wood finish". My personal preference is for an oil/varnish mixture treatment. Either use Minwax Tung Oil Finish, Minwax Antique oil or a homebrew of equal parts of boiled linseed oil, your favorite varnish or poly varnish and mineral spirits. Sand the benchtop up to 180 grit. Apply the mixture heavily and keep it wet for 15-30 minutes. Wipe off any excess completely. Let it dry overnight and the next day, apply another coat using a gray non-woven abrasive pad. Let it set and then wipe off any excess. Let this dry 48-72 hours. To prevent glue from sticking apply a coat of furniture paste wax and you're done. This treatment is somewhat more protective than the wax and mineral oil as the varnish component adds some protection from not only water both some other chemicals also. The waxing makes the surface a little more impervious to water so you can wipe up any liquid adhesive. It also allows hardened adhesive to be scraped off. Repair and renewal is easy. Just go throught the same scraping, wiping down with mineral spirits and reapplication of the BLO/varnish/mineral spirits mixture and an application of paste wax. Both of the above treatments are quite protective but are easy to maintain and renew. They do not fail when the surface takes a ding.

I agree wholeheartedly with Curt's suggestion. What he is describing is basically homemade WATCO Danish Oil. Either his homemade version or the commercial version will work.

My preference, after using lots of WATCODO and homemade oil/varnish mixtures is to eliminate the linseed oil entirely. It adds nothing of real value, but stinks, tints the wood yellowish, and slows down drying time. The oil is a traditional leftover from days when there was little else available and tung oil-based varnishes were expensive.

A good polyurethane thinned 100% with a good quality thinner, allowed to soak in, and sanded with WD paper (the sandpaper process forces the thinned varnish deeply into the wood's fibres where it is needed most, and creates a wood dust/varnish slurry that fills the grain and helps to slow down moisture transfer, and actually does harden), repeated 3 times over 4 days, will do a better job. Wipe off the last slurry, while still wet, with a clean rag so nothing remains on the surface.

I also strongly agree with Chris's recommendation for a final coat of paste wax (w/o silicone). If you use the kind intended for floors, it will be nonslip.

2d

[Chris Fournier]

I use a boiled linseed/spar varnish mixture and it is scraped off and reapplied when my bench looks shabby and that depends on the project line up. It is a quick and dirty task. I don't use wax, the only sticky wax I've used is on my skis. Paste wax is slippery and holds dirt. Not good.

[Malcolm Schweizer]

If one were to split hairs, I would say coat all surfaces so the wood gains and loses moisture evenly. This would be a very minor possibility for uneven movement, but for example- wet one side of a board and put it face down in the sun, allowing the other side to dry, and you will see an exaggerated example of what I am describing. I feel the need to reiterate here that I am saying there is some possibility of a tiny bit of uneven wood movement, probably not enough to worry about, but if you can get to the bottom side then do a light coat.

As for workbench finishes, a historic recipe is 1 ounce beeswax dissolved into 8 ounces of pure gum turpentine, then add 8 ounces of raw linseed oil. You don't need to heat the wax!!! Shave it into the turpentine with a cheese grater (one you don't ever want to use again for any other purpose) and the turpentine dissolves it. I put it in the warm sun to speed up the process, but it only takes 20 to 30 minutes to fully dissolve otherwise. If not, perhaps you don't have pure beeswax or pure gum turpentine. You can add more beeswax than just one ounce, but you will be thickening the mix, and eventually if you add too much then you will need heat to melt it, and you end up with a paste instead of a brushable liquid. I probably use about 2 ounces. I don't measure it- I just add it until it looks about right.

Put the mix in the hot sun and apply it warm. Don't heat it on a stove- no need for that fire hazard- just warm it in the sun. This allows the wax to fully penetrate the wood. When it dries you can buff it to a bit shinier finish or leave it matte. Obviously for a workbench you want to leave it matte, but I mention this for reference, as this finish works well on furniture.

"But Malcolm- I thought you had to use boiled linseed oil or it will never ever dry until long after you are dead." Bah, humbug! The turpentine aids the drying process. It will be a bit tacky (not much, but noticeable) for a week. It dries with a very nice matte finish. You certainly can use boiled linseed oil for quicker drying, but it has all sorts of drying agents in it these days. I love the smell of pure gum turpentine and linseed oil. (Not the cheap turpentine- it smells horrible.) Add some lemon or almond oil if you like to tone down the smell.

[Pat Barry]

I used the BLO and wax treatment on my Ash benchtop and although its a bit slippery I'd rather have that because the top serves double duty for me as an occasional outfeed table for my table saw and an assembly / glue-up table. I have had countless glue spots on the top and they pop right off the BLO / wax surface. If I had the space to have dedicated benchtop I'd probably skip the wax on the top though as the slipperiness isn't the best thing for working on top of the bench doing handplaning for example.

[Reinis Kanders]

I also have ash benchtop. No finish, I plane it a bit to make it flat or if it gets too dirty, i like the light color of unfinished ash.
Sometimes I slap some leftover shellac on the bench legs that are made out of fir.
One or two coats of brushed dewaxed shellac are not that slippery and also keep glue off and are ready to use in 10 minutes.

[george wilson]

Boiled Linseed oil is what I use. Danish oil has a cold look about it that I don't care for. Linseed oil can get moldy in an unheated shop. Tung oil would be better in that case. But,linseed oil has a warmer look. We did have to resort to tung oil in the Toolmaker's Shop for tools that were left in unheated sheds in the museum.

My own bench was given a good coat of linseed oil,and has never been a problem. But,my shop is heated and cooled. It has been several years,and my bench could stand another coat,if I ever got it cleared off!

[Nathan Callender]

Thanks all. I just got he leg vise installed so a quick sanding and then I think I'll just crawl under the thing and give it a single coat of Danish oil on the bottom. How much of a mess can that be, right?!

[george wilson]

not much if it doesn't drip in your eyes!

[Prashun Patel]

I find it interesting that there is religion about what is 'right' and 'wrong' on a bench.

For my part, I've had a film finish on one bench, none on another, and an oil-varnish on yet a third. If you do not mind if your bench looks worn, then it really does not matter. Having SOME finish prevents glue sticking, but I find all the fears about benches being too slippery from wax, or that a film finish getting cut will be ruined are all hogwash in practice.

Stuff slips on a bench if it's not held or stopped properly. Film finishes may not look wonderful if they get little cuts in them, but that's purely aesthetic - and even then, with enough dings and use, it really doesn't look 'bad' and my eye is as critical as the next guy's.

Nowadays, I tend to wipe/pour, brush out excess finish from any project onto my bench. It's more for drying the rag than it is protecting the bench, but it does give me an excuse to dust her off and pretty it up a little bit.

[Malcolm Schweizer]

I find it interesting that there is religion about what is 'right' and 'wrong' on a bench.

For my part, I've had a film finish on one bench, none on another, and an oil-varnish on yet a third. If you do not mind if your bench looks worn, then it really does not matter. Having SOME finish prevents glue sticking, but I find all the fears about benches being too slippery from wax, or that a film finish getting cut will be ruined are all hogwash in practice.

Stuff slips on a bench if it's not held or stopped properly. Film finishes may not look wonderful if they get little cuts in them, but that's purely aesthetic - and even then, with enough dings and use, it really doesn't look 'bad' and my eye is as critical as the next guy's.

Nowadays, I tend to wipe/pour, brush out excess finish from any project onto my bench. It's more for drying the rag than it is protecting the bench, but it does give me an excuse to dust her off and pretty it up a little bit.

I don't think it is a right or wrong thing, but rather just what works best for the individual. The oil and wax finish allows even epoxies to scrape right off. That's what sells me on it.