What's those silvery patches?

[GrahamRounce]

Hi - I got some wood from a reclaim yard. The man said it was "Redwood, cedar". A bright pink colour. But from what I've seen, cedar is used for decking etc, and this stuff is as light as balsa, nearly, and as soft, except for the summer (or is it winter?) rings, which are as hard as nails. I turned some legs with it, and it was difficult to keep them round when sanding, as the hard parts didn't want to go down, and the soft parts went down at a touch.
Any idea what variety this might be? It's quite attractive, anyway.

But also, after finishing with Rustins PC (with some acrylic colourant mixed in) a few days ago, they are now developing silvery patches which I'm hoping will go away with a light sanding and another coat. Is it something out of the wood? I haven't had trouble with the colourant (Trylon) before.

Thanks,

Graham

 

[cornucopia]

from the description of the wood it sounds just like wellingtonia which is from the sequioa family

any pics?

 

[GrahamRounce]

>> Any pics?

Yes, certainly. The colour doesn't show up too well, though. The smaller piece behind has a test application of RPC with amber colourant - it comes up quite nice.

You can't see the silvery patches on the leg very well, either - pls just take my word for it. (The big patch is a reflection - the patches I mean aren't quite that silvery!)

 

[GrahamRounce]

I lightly sanded and RPC'd again. Covered the silvery patches well. But after a couple of days they reappeared.
So I skipped the sanding before RPCing again. Again they were covered over nicely, but after another couple of days, there they are again! Not so much, but still there.

It's like whatever it is floats to the top, even after the RPC has apparently hardened! Ever tried to cover biro with white emulsion? Put as many coats as you like on and it still won't cover. It's like that.

I'm wondering if Wellingtonia is one of those woods that can have calcium deposits, because I think I did notice some shiny dots in it. And the bandsaw seemed to struggle in places. Could that be it? Would calcium deposits spread into uncoverable patches?

It's a bit of a mystery to me, but then plenty is...

Any ideas gratefully received, because the wood's nice otherwise...

Graham

 

[Derek Willis.]

I know nothing about the species of timber, but, could it be that you are using a water based stain in a chemical finish, I would have used a spirit stain in RPC being more compatible.
Derek.

 

[GrahamRounce]

Derek, thanks - the Trylon is supposed to be for colouring casting resin, so I was just guessing it would be in roughly the same family as RPC.
It's a bit of a mystery, as it's only happening to the table legs. Test pieces (above pic, and various other small pieces of the same wood and tulipwood) were fine.
Also, it seems weird to me that the patches gradually appear over 3-5 days - long after the coating should have hardened?