Sealing workbench top

[stickshift]

For a workbench top, I'm planning on using two layers of 3/4" sheathing plywood topped by 1/8" tempered hardboard.

The workbench will have a roof over it protecting it from being rained on directly, but otherwise exposed to the elements.

Suggestions on inexpensive way to seal the top and edges? Seems like I should also seal the underside of the bench top since that will be exposed to the elements as much as the top side. How about the surfaces that are mated to each other in this 3 layer sandwich - should those be sealed as well?

Polyurethane? I'd rather not wait 4 hours between coats and have to sand between coats. I've heard the water-based polyurethane is a lot easier to work with - much shorter drying time and no sanding necessary.

 

[pablo94sc]

Get all-in-one stain and sealant for decks. I used Olympic canyon brown on mine to help protect it from spills and water rings and it is a nice, rich brown with red undertones.

 

[Neutron357]

Use a marine grade polyurethane.


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[Cyberbear]

I'd opt for what salt water boat owners use in this situation. You probably won't mind the wait between coats after the bench is still water resistant several years later. I'm still not convinced that water based spar varnish is as good as the slow drying stuff. Only time will tell.

 

[stickshift]

I'd opt for what salt water boat owners use in this situation. You probably won't mind the wait between coats after the bench is still water resistant several years later. I'm still not convinced that water based spar varnish is as good as the slow drying stuff. Only time will tell.

It's not the drying time that is the big pain for me. It's the sanding between coats.

 

[stickshift]

Get all-in-one stain and sealant for decks. I used Olympic canyon brown on mine to help protect it from spills and water rings and it is a nice, rich brown with red undertones.

You use this on your workbench top? Are multiple coats required?

 

[biowrench]

It's not the drying time that is the big pain for me. It's the sanding between coats.

I don't get the mental block on sanding so many seem to have. Hand block or air tool, it's all zen, on all-planar stuff quick and easy. Make a long narrow sanding block and you'll never round or bevel an edge, and it just takes three quick back-and-forth passes to get the job done.

 

[biowrench]

For a workbench top, I'm planning on using two layers of 3/4" sheathing plywood topped by 1/8" tempered hardboard.

How about the surfaces that are mated to each other in this 3 layer sandwich - should those be sealed as well?

Having in the last month laminated about a half acre of baltic birch with various veneers, mdf, and of course more plywood, for artistic and architectural applications, I suggest you do not "seal" any of those mating surfaces. The glue will do it. Scuff the surfaces up, prepare your clamping system (!), roller slightly thinned out waterproof wood glue (titebond is fine) on all surfaces, quickly squeegee off excess, pre-align and mate the sheets, finesse until the edges line up, shoot a few little finish nails in to hold, and clamp.

How do you plan to clamp it? We use 5' x 10' screw-clamp beam presses, but that's just us.

 

[nadogail]

I use poly urethane on my bench. For clamping I would use weights, read 5 gallon paint pails (fill with water).

 

[stickshift]

Having in the last month laminated about a half acre of baltic birch with various veneers, mdf, and of course more plywood, for artistic and architectural applications, I suggest you do not "seal" any of those mating surfaces. The glue will do it. Scuff the surfaces up, prepare your clamping system (!), roller slightly thinned out waterproof wood glue (titebond is fine) on all surfaces, quickly squeegee off excess, pre-align and mate the sheets, finesse until the edges line up, shoot a few little finish nails in to hold, and clamp.

How do you plan to clamp it? We use 5' x 10' screw-clamp beam presses, but that's just us.

I wasn't planning on gluing, which is why I was thinking I'd need to seal the mating surfaces. Don't have the clamps to glue up such a large surface. No experience with glue-ups either, but I suppose there's a first time for everything.

Would screws provide sufficient clamping force? Could also add weights as suggested above, if that adds anything to the force the screws would provide.

Is Titebond II the stuff to use? Seems they market that as waterproof, while they don't market Titebond I that way. No idea if there's a real difference or if it's just marketing.

 

[rieferman]

For a workbench top, I'm planning on using two layers of 3/4" sheathing plywood topped by 1/8" tempered hardboard.

The workbench will have a roof over it protecting it from being rained on directly, but otherwise exposed to the elements.

Suggestions on inexpensive way to seal the top and edges? Seems like I should also seal the underside of the bench top since that will be exposed to the elements as much as the top side. How about the surfaces that are mated to each other in this 3 layer sandwich - should those be sealed as well?

Polyurethane? I'd rather not wait 4 hours between coats and have to sand between coats. I've heard the water-based polyurethane is a lot easier to work with - much shorter drying time and no sanding necessary.

So you're basically building an outdoor workbench that is under a car port roof (or similar), right? If yes, a couple layers of nice 3/4" sheathing that has a nice long exposure rating (I thin advantech is one) will last a lonnnng time with the minimal exposure it will see in your case. The tempered hard board will be your problem. I would either skip that layer, or choose another product in your situation. It is so prone to swelling.

 

[MoonRise]

Is Titebond II the stuff to use? Seems they market that as waterproof, while they don't market Titebond I that way. No idea if there's a real difference or if it's just marketing.

Titebond I = 'regular' yellow aliphatic non-water-resistant wood glue

Titebond II = water resistant version

Titbond III = water-proof version

That's the short version. Full up explanation at the Titebond website.

http://titebond.com/index.aspx

http://titebond.com/woodworking_glues.aspx

 

[stickshift]

So you're basically building an outdoor workbench that is under a car port roof (or similar), right? If yes, a couple layers of nice 3/4" sheathing that has a nice long exposure rating (I thin advantech is one) will last a lonnnng time with the minimal exposure it will see in your case. The tempered hard board will be your problem. I would either skip that layer, or choose another product in your situation. It is so prone to swelling.

Yes, covered so no rain will hit it except for perhaps the very occasional strong thunderstorm with very high winds.

Like this stuff?
http://www.homedepot.com/p/Unbranded-23-32-in-x-4-ft-x-8-ft-RTD-Sheathing-Syp-166103/100041308

The only more weather resistant option I see at Home Depot is pressure treated plywood.

I could skip the tempered hardboard. I was thinking of using it for a couple of reasons:
1. easily replaced sacrificial top
2. nice smooth surface that doesn't splinter like plywood

I know it can swell up, but was thinking that it might be fine if sealed with a varnish.

 

[MoonRise]

Put a tarp over the workbench so it doesn't get wet you are aren't using it. Done.

What is the 'purpose' of this workbench? Anything-everything, woodworking, metalworking, engine rebuilds, what?

The sacrificial hardboard top layer isn't a bad idea for a woodworking or GP bench IMHO, but it may or may no be the 'right' surface.

A couple of coats of poly (water-based or oil-based) will 'seal' the hardboard pretty well.

If you follow the coat-dry-recoat times on the label (RTFM, for-the-win ), and you aren't looking for a furniture, lacquered piano, or auto paint level of finish you can usually just do a very quick scuff sanding (scotchbrite-type pad, or relatively fine sandpaper) between coats. With a 1/4 sheet or ~5" RO power sander, you can scuff sand a 4x8' sheet of 'wood' (hardboard, plywood, whatever) in between coats of finish in like 10 minutes tops.

 

[Falcon67]

I use porch/concrete paint. None of my benches are exposed, but the paint is cheap, decently tough and easy enough to re-fresh. Can be mixed in your choice of color too.

 

[stickshift]

Put a tarp over the workbench so it doesn't get wet you are aren't using it. Done.

Nah, too much hassle, and too ugly.

What is the 'purpose' of this workbench? Anything-everything, woodworking, metalworking, engine rebuilds, what?

General purpose light DIY. Not putting anything very heavy on it.

The sacrificial hardboard top layer isn't a bad idea for a woodworking or GP bench IMHO, but it may or may no be the 'right' surface.

Alternatives that provide a nice smooth, non-splintering surface? I like that tempered hardboard is inexpensive. 1/8" 4x8 sheet is $8 at my local HD. Tough to beat that I would think.

A couple of coats of poly (water-based or oil-based) will 'seal' the hardboard pretty well.

Yep, that's what I'm thinking.

If you follow the coat-dry-recoat times on the label (RTFM, for-the-win ), and you aren't looking for a furniture, lacquered piano, or auto paint level of finish you can usually just do a very quick scuff sanding (scotchbrite-type pad, or relatively fine sandpaper) between coats. With a 1/4 sheet or ~5" RO power sander, you can scuff sand a 4x8' sheet of 'wood' (hardboard, plywood, whatever) in between coats of finish in like 10 minutes tops.

No power sander, would use block sander. Yeah, not looking for a fine finish, so just a quick scuff to give the next layer of poly something to bond to would be sufficient. It's just a lot of work compared to a one coat process or a multiple coats with no sanding process, which is what I was hoping for.

 

[Hawk]

Coat both sides of the hardboard and it will last pretty well. Just coat one side and you may as well not coat it at all. Outside it will wick moisture from the air from the uncoated side even when fastened down to another strait.

 

[kbs2244]

Instead of the brown stuff get the pre-finished white stuff.
It is the same but with a white finish.
It is sold as a cheap wash room paneling.

No finshing coat needed.
The white will be easier to work on and the finish is water and chem resistant.
I use it as work bench tops and have found it will stand up to anything but acetone.

 

[stickshift]

Instead of the brown stuff get the pre-finished white stuff.
It is the same but with a white finish.
It is sold as a cheap wash room paneling.

No finshing coat needed.
The white will be easier to work on and the finish is water and chem resistant.
I use it as work bench tops and have found it will stand up to anything but acetone.

This stuff?
http://www.homedepot.com/p/EUCATILE...d-Thrifty-White-Tile-Board-HDDPTW48/205995949

 

[Nowater]

The white stuff scratches too easily. Try BLO on the hardboard. Thin with spirits. No sanding between coats. Put on two coats then wait a week for another couple of coats.

 

[stickshift]

The white stuff scratches too easily. Try BLO on the hardboard. Thin with spirits. No sanding between coats. Put on two coats then wait a week for another couple of coats.

Problem with that is it doesn't really seal off the wood. There's a Wood Whisperer video comparing oil and varnish (urethane and the other varnishes). The fibers soak up the oil, but because it's not sealed, moisture can get in. Need a barrier like varnish or lacquer or shellac to prevent that.

 

[Shiftless]

From time to time, at a friend's house out in the wilds of northern california, I use an outdoor workbench like what you are describing. It has a roof of corrugated fiberglass. Open on 3 sides. 60 inches of annual rainfall. Dirt floor. 3 feet by 10 feet made of unfinished 2x8 redwood planks. 50 years old and still doing the job.

 

[kbs2244]

I cannot tell from the HD site if that item is embossed with fake tile lines.
If so then I wouldn’t use it for a bench top.
I would prefer something smooth.
But it the kind of thing I was talking about.
Sometimes the smooth stuff has a kind of tacky looking fake marble print.
I have used it anyway.

In typical home/hobby use this kind of top has lasted over 5 years.

I got the idea originally when I helped a guy that ran a motor and starter re-build shop.
He had all the work benches topped with it.
He replaced the tops every year when he did a year end shutdown.
But they were under day to day abuse.