Sapwood for external door
- This topic has 20 replies, 7 voices, and was last updated 4 years, 4 months ago by
.
-
Posts
-
Well, I’ve made furniture (and doors) from Oak for decades.
Apart from the economics and aesthetics of the piece, I always, always, always cut out sapwood for one reason alone – Wood-Worm.
Oak sapwood is the natural home for these beasts. It’s soft in texture compared to the harder heart-wood and contains nutrient even when dead. They love it and they’ll find it, usually out of sight. Sooner or later, whatever it’s painted with will decay.
As an example, go to an old church. Look at all the Oak in the screens, beams, pulpits and try to spot the sapwood. There won’t be any.
Sorry to say this but for quality work, sapwood is considered waste, along with the bark and pith at the core of the tree.What I’ve said is bound to disappoint…. just stating a fact.
First coat of varnish over water based dye stain shows no incompatibility.i put a second coat on, but it seems to work just fine.
Apart from the economics and aesthetics of the piece, I always, always, always cut out sapwood for one reason alone – Wood-Worm.
Maybe in Wales, but that’s Not an issue on this side of the pond.
The only wood-worm we get here is in absinthe.
Oh wait. That’s wormwood.While that would be a consideration for something like outdoor furniture here, that would not be a real issue for kiln dried lumber used in something like a finished door. If you have beetle larvae in a door the issue is improper protection, not sapwood. My varnished Douglas Fir front door has the bottom rail with sapwood in it which I installed 18 years ago and is as sound as the day I installed it. Pseudotsuga menziesii is considered moderately susceptible to insect attack in the wood database, but that’s in wet wood. The only issue is that while the rest of the door has aged to a nice reddish brown, the sapwood is still white. I’ll have to tint that someday or just cover it with a nice bronze kickplate.
And one species of wood with beetle infestation is highly prized and comes at a premium. Pecky Cypress is an infestation of Bald Cypress by beetle that eat a fungus growing in the dead wood. $20 / bdft is not unheard of. https://www.westwindhardwood.com/product/hardwoods/pecky-cypress/
That’s more than the going rate for Bubinga or real Honduran Mahogany at my local supplier.
Thank you all for the great advice, quite an education. There is so much more to a simple door than I dreamed of! The debate and differing techniques will really guide me through each stage of the work as I get to it. I guess it will teach me to visit the wood yard when I need more wood rather than rely on “mail order” even if they come highly recommended by Paul S!
I am very grateful!!
@LR1994 I’m confident in my finishing comments, but listen to the other guys when it comes to the oak sapwood. I was not aware of some of the issues they raised.
@lorenzojose thank you for trying that finishing experiment. It’s good to know! Which alkyd varnish did you use? Epifanes?@lorenzojose thank you for trying that finishing experiment. It’s good to know! Which alkyd varnish did you use? Epifanes?
Yes. It’s what I had on hand. I know minwax tung oil finish also works. I used that sometimes on saw handles- mostly to see what effect it gave. I’ve gone back to several coats of shellac and a top coat of any wiping varnish. I get a smoother finish more quickly.
I do something a little different, but for very similar reasons. The dye goes on because I like dye. Since it is water based dye, shellac can pick it up, e.g., if I get a run in the shellac, it can cause a problem. So, I put a coat of oil based finish, typically Arm-R-Seal, over the dye as a barrier coat since the Arm-R-Seal won’t pick up the dye. Also, on figured wood, I think the oil based varnish improves the figure. With the water born dye locked down, I then switch to water born finish to build coats. I think this is the same reason as why you use shellac. Three coats of water based finish and I’m done rather than wiping many coats of oil. I can be done with all of those coats in a day. The slow part of my method (Charles Neil’s method, really, since he taught me) is waiting for the Arm-R-Seal to dry enough to put the water based finish over it. Now, if I’m spraying and if I don’t care about the aesthetics of the oil layer for highlighting the figure, then I’ll just wait for the dye to dry, spray a dry coat of water based finish, i.e., light enough that there’s zero chance of a run, and then move on to the three real finish coats. Your approach probably has the advantage of having the top layer be varnish, which may be a tougher finish than the water base stuff in some cases.
I wonder if yours is easier to repair because, if something happens, you can sand through just the varnish and into the main layer of shellac, do the repair, blend new shellac in, and then wipe a new topcoat of varnish? With what I do, the repair will always involve repairing water base finish.
- You must be logged in to reply to this topic.