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View Full Version : Trouble with BLO/CA



Nicholas Briggs
08-21-2007, 9:07 PM
I've used BLO/CA a few times with great results. But my last 3 pens all have the same problem. They look right as they come off the lathe, but after I assemble and they have been sitting for a day or so some of the finish seems to just be gone. There are rough spots, as if the CA had receded. These spots are most often on one end or the other of the blank. Anyone have this problem before?

Jim Becker
08-21-2007, 9:34 PM
Are you letting the BLO cure before you apply the CA? That's like a week or so...when the smell goes away, the oil is cured.

Patrick Taylor
08-21-2007, 10:13 PM
Are you letting the BLO cure before you apply the CA? That's like a week or so...when the smell goes away, the oil is cured.

I never let the BLO cure before applying CA. I follow Russ Fairfield's method, like many others, so I don't think this is an issue. I suspect a sanding/polishing issue, where the whole thing looks great in one light, but when you get into another light you can see spots with less luster. It's common for CA finishes I think if you're not careful to sand and polish thoroughly after doing your last CA coat.

Just my opinion. :)

Jim Becker
08-22-2007, 9:22 AM
NP...I was using conventional thought in my question...which likely doesn't apply! :)

Patrick Taylor
08-22-2007, 9:37 AM
Jim, your comment actually makes me wonder what's happening inside that waterproof/airtight layer of CA if BLO has not cured. Does it ever cure? I think the BLO gets mixed in with the wet CA during the application, and perhaps the CA chemical reaction or exotherm has some curing effect on the BLO? This is all speculation, and I wonder if anyone knows the right answer!


(sorry to hijack, Nicholas, but I think we're still on topic!)

Ron Raymond
08-22-2007, 12:17 PM
A few months ago, Russ penned a rather lengthy discussion over on IAP about whether you should use BLO first and then CA, or CA first and then BLO. It was very technical, very specific, and way over my head!:confused: But the bottom line is that he recommends CA first and then BLO. His results speak for themselves.

I understand it would be a TOS violation to post a link to that other place. Maybe Russ could do a cut-and-paste here on SMC? (hint, hint)

Nicholas Briggs
08-22-2007, 3:54 PM
Thanks for the replies guys. My biggest frustration is that I have done a good BLO/CA finish in the past. Some of them came out very nice. Not sure what I'm doing different. Perhaps the brand of CA? I usually do about 3 coats, sanding from MM 2400 - 12000 in between each coat. I've also noticed that my recent pens have a softer finish, it is easy to leave a dent on them with your finger nail. I suppose this could be due to the type of wood though.

Kevin McPeek
08-22-2007, 3:54 PM
When I first started with that method I had that happen a couple times. Now I always friction dry the BLO and usually let it set overnight before CA goes on. I also found that more, thinner coats of CA works better than a few thick ones.
After changing my method I have never had a finish go bad.
Now only if I could get the same consistancy on bowl finishing.

Nicholas Briggs
08-22-2007, 3:58 PM
Thanks for the tip Kevin. Now that you mention it, I think I was using medium CA before, and now I am using think. I'll try some of the old stuff and see how it comes out.

Nancy Laird
08-22-2007, 4:02 PM
Nicholas, you might also try sealing the BLO with shellac, then going to the CA.

Nancy (121 days)

Rich Stewart
08-22-2007, 11:00 PM
My can of BLO states the oil is absorbed into the wood and excess should be wiped off or it will cause a "GUMMY MESS".