blo and shellac

[oakey]

two questions first is it possible to seal coat with shellac then apply BLO to cherry
or will the shellac seal the wood and then the BLO will just sit on top ?
i am trying to slightly darken cherry BLO works great for that and i have used it a lot in the past
but BLO leaves splotches on cherry with busy grain patterns .
some times i do not care if it splotches / highlights the grain this time i do
also will general finish water base be as durable as there oil base?
i always use oil base this time i would like to use an hvlp gun and water base is so much easier clean up

[fredhargis]

What you suspect is true, the shellac will seal the wood making it not-very-useful to apply BLO. If you just want to slightly darken the cherry, just wait a week. Sit in the sunlight of you want. But it will get there on it's own. As to durability of GF products, my opinion is that generally speaking the waterborne finishes have really come a long way, and GF offers some of the better ones. But I guess I still see them as slightly less durable than the good oil based finishes and more likely it probably depends on which GF finish you want to compare to what oil based finish.

[Scoony]

Thin out the shellac a little. It will absorb other finishes and stains. I would probably not use BLO over itl but would use some sort or varnish. Minwax Antique Oil looks great on cherry and is easy to use.

[jteneyck]

Surprise, but shellac can blotch on cherry, too.  I never would have thought that to be true until I made some sample boards. On the left is Arm-R-Seal on cherry.  In the middle, is Sealcoat shellac, followed by ARS.  On the right is BLO followed by ARS on the top and Sealcoat then ARS on the bottom.  



The least blotchy was ARS alone.  The worst, was BLO + Sealcoat + ARS.   Note, these specimens were done by hand.  If you spray shellac it won't blotch.  Since you want to spray the final finish you could start by spraying shellac.  If you want it as dark as BLO then add some Transtint dye to the shellac.  A little Reddish Brown or Medium Brown would be what I'd look at first.  I make 15 or 20 ml samples and count drops of Transtint until I get the color and ratio correct, then scale up to what I need for the project.  

If you want to use a WB topcoat you should only use dewaxed shellac underneath.  I use Sealcoat.   And about WB topcoats.  There are some really good ones these days.  GF's EnduroVar is pretty close in chemical durability to oil based varnish.  GF's or Target Coatings Conversion Varnish are right there with any oil based varnish.  I haven't used it, but I'm told by a couple of guys I trust that TC's version, EM-8000CV I think it is, sprays great.  

Just to show you what Sealcoat + Transtint followed by EnduroVar looks like here's a photo of a cabinet I made to match a 20 year old commercial one.  


 

John

[cputnam]

I've had success with a spit coat (1 lb-ish cut) sanded back so that shellac is left in the grain that will blotch (end grain). Then BLO and then shellac and then top coat(s)