Will Thinned PVA White Glue block Boiled Linseed Oil?

[Bill McCarthy]

I'm getting close to the completion of the assembly of my first workbench. http://www.sawmillcreek.org/showthre...is-Good-Enough

I'm having some surgery this coming Wednesday and won't be able to lift anything heavy for 6 weeks afterwards. I figured this would be a good time to apply a finish to the bench. Because the entire bench build is a learning experience for me, I've decided to experiment.

I plan on making my own wiping varnish (I think that's what its called) using the 1/3, 1/3, 1/3 approach of Boiled Linseed Oil, Polyurethane, and Paint Thinner. I also have some old stain kicking around that I was going to use. I have a 1/2 pint can of Minwax oil based stain and a pint can of General Finishes water based stain (the label says its Cherry but it looks more like walnut).

The bench is made from SPF 2x4s from Home Depot. I wanted to experiment with using thinned white PVA glue (Elmer's) as a blotch control.

If I apply the thinned glue, will it prevent the BLO in the varnish from penetrating into and being absorbed by the wood?

Although I always want to have a nice finish, this is an experiment to find out what happens, so if the colors don't turn out the best, I'm not going to worry about it. I'm looking for an even color with the varnish on top.

I've never done any of this before, so I'm not sure what to expect.

[Jim Becker]

Yes, sealing the wood with thinned glue is going to affect absorption of the oil.

I suggest you consider not using a film finish on a workbench. Just the oil is fine and it's more easily renewable. Workbenches need to be maintained from time to time and a film finish (which includes a wiping varnish) Will show the places where cuts and chips that routinely occur on a well used workbench occur. I just use BLO and re-apply maybe 3-4 times per year after cleaning up the top.

[Bill McCarthy]

Jim, will the oil alone be enough to prevent glue from sticking? As in, if I glue some piece together will I need to worry about it sticking to the bench strong enough that it now becomes part of my bench?

[Jim Becker]

I've never had something get glued to the bench to-date...and removing glue drips has been easy, too.

[Bill McCarthy]

Thanks. That's good to know.

I did think of another question this evening. Can I use the BLO as a sort of blotch control? If I put one coat of oil, then stain it, would that help me? I'm thinking of the legs now, not the top?

[Jim Becker]

"Blotch" is merely the uneven absorption of oil or a colorant by the wood...so "no", BLO isn't going to help "control blotch". It will enhance the beautiful figure...which is what I consider it. For me, there is no "blotch". The best "blotch" control is very careful selection of lumber for a project so that each piece of material reacts to the finishing process as closely as possible to the next.

[glenn bradley]

I've used just BLO and a bit of paste wax on bench tops for years. Glue drips pop right off.

[mike wacker]

Hope I'm not taking the thread too off tangent, but a trick I literally stumbled accross for glue drips is to roll out parchment paper over my work bench/assembly table when doing glue ups as a barrier between the bench top and my project. Even polyurathane based glue flakes right off the paper after curing. Then I roll up the paper and stick it in a tube to be used again. Parchment paper is cheap (found in the baking aisle of your local grocery store in case you weren't familiar) and lasts a long time given a little care.

My point is if you use parchment paper you can be less concerned about glue dripps regardless of what finish you choose.

[Jim Becker]

Mike that can help as long as you're not needing to use various dog holes for hold-downs, etc., while doing the glue-up.

[Bill McCarthy]

Hope I'm not taking the thread too off tangent, but a trick I literally stumbled accross for glue drips is to roll out parchment paper over my work bench/assembly table when doing glue ups as a barrier between the bench top and my project. Even polyurathane based glue flakes right off the paper after curing. Then I roll up the paper and stick it in a tube to be used again. Parchment paper is cheap (found in the baking aisle of your local grocery store in case you weren't familiar) and lasts a long time given a little care.

My point is if you use parchment paper you can be less concerned about glue dripps regardless of what finish you choose.

I've also used waxed paper in a similar fashion. But sometimes I can be absent minded and forget to use things like that. That's why I'm concerned about a finish that the glue won't adhere to.

Jim Becker

"Blotch" is merely the uneven absorption of oil or a colorant by the wood...so "no", BLO isn't going to help "control blotch". It will enhance the beautiful figure...which is what I consider it. For me, there is no "blotch". The best "blotch" control is very careful selection of lumber for a project so that each piece of material reacts to the finishing process as closely as possible to the next.

Jim, I understand what you are saying regarding whether its blotch or not. But back to my question. If blotch is caused by different amounts of absorption, in the various parts of the wood, won't the oil be absorbed more in certain areas than others? If that happens, will the stain then be more apt to be absorbed more evenly, because those areas already have more oil?

[Jim Becker]

Jim, I understand what you are saying regarding whether its blotch or not. But back to my question. If blotch is caused by different amounts of absorption, in the various parts of the wood, won't the oil be absorbed more in certain areas than others? If that happens, will the stain then be more apt to be absorbed more evenly, because those areas already have more oil?

I doubt it...and the combination of the oil and the subsequent (presumably oil based) stain would just exacerbate the look. When in doubt ALWAYS test on scrap to see how things work and always do the full finishing regimen at least through the first coat of any clear, documenting what you did, etc., for repeatability.