WOODWORKING QUIZ for 7 Nov 04

[Ralph Jones]

Good Morning Friends,
When you plan to paint cedar, be sure to properly prime it first. Otherwise, the colored extractives, resins, and oils that cedar contains may leach out and discolor the paint.

How or what steps would you take to prevent this from happening ?

Respectfully,

[Robert WA]

Ralph.
Probably not the answer you are looking for:
A hardboard product called Masonite had a habit of leaching out dark stain into any paint finish applied to it. I would prime it with a finish paint called Silverfrost and that seemed to prevent the staining. I guess there is a primer that will seal in the resins of cedar.
I have not seen Masonite as a hardboard or Silverfrost as a paint for years, so don't know if they still exist under those names.

[fxst]

Robert masonite is still around I actually bought some the other day and so is silverfrost but now is alsomething (I forgot)
Ralph why paint it I just use linseed oil on western red cedar
so I guess its the wrong answer

[journeyman Mick]

Ralph,
by "cedar" I'm assuming you mean western red. It's a native to your country but is imported here, its main uses here are joinery (doors and windows) and bevel weatherboards. Besides one, all the jobs I've worked on that used WRC used some type of clear finish or stain. The one exception was an owner builder job and they painted it themselves (purple and green! :eek: ).
I'm assuming that like any timber prone to staining due to exudates etc it should be primed with an oil base primer.

Mick

[bitingmidge]

I have not Silverfrost as a paint for years, so don't know if they still exist under those names.
It still exists allright! I've got a can in my cupboard somewhere... was all my old man ever used for undercoating...also topcoating come to think of it...and rustproofing....and I love the smell tooooowhooooohooooooo!!!

(Could explain a lot!)

It was sort of a paint version of WD40 in our household!

Cheers,

P

[Ralph Jones]

Good Evening Friends,
You all are correct that there are other alternatives to Western red cedar but a lady client wanted Adirondack chairs made out of it and then wanted them painted white. what I did was to use a good oil based primer and hit the knots first, with a couple coats then the edge grain that soaked up primer like a sponge. I let them dry overnight and then primed the entire projects with the same oil based primer and allowed the chairs to dry and cure for about a week. Then came back with two coats of a good quality exterior latex paint, that was five years ago and they still look good.

She informed me that they would wash them at least once a week without any change in the finish.

Personally I prefer a natural finish of tung oil myself.

Thank you for your support.

Respectfully,