I finally completed a wrap using Madeira threads and cp. After i let the cp dry for about 36 hours I applied my finish. I hit the finish with a little heat to remove the air bubbles. After about 6 hours I checked on it and every now and then was some air bubbles. I'm pretty sure it was air trapped in the threads by the cp. Any suggestions on what I might have done wrong or a way to prevent this in the future?

BTW....I too have come to the conclusion that cp problems are those of the person using it. I saw what my mistakes were in applying it and it has made me to better my application technique. I ended up cutting the wrap off though. I just didn't like it. LOL

Thanks,
Steve

I'm sure others will chime in but Tom gave me a great tip on applying cp - (which I don't normally use). He said to sort put alot on with a spatula, let it roll around on the wrap while turning the rod, and then wick the excess off the bottom exactly like when using epoxy. I believe he said if you use a brush to apply, that is what intriduces air bubbles into it. Plus I always had trouble with the original edge getting "tacky" by the time I got it all the way around the wrap. I'm a spatula lover forever.

The CP can't trap air and then release it when you apply finish. If anything, the CP will displace the air and seal the threads so you really shouldn't have to deal with thread related air bubbles. If the CP did trap any air in the form of bubbles they should have been apparent before you applied the finish.

Sometimes a bubble or two will try to escape from the guide foot tunnel. Sometimes you add them when you "brush" the finish and then they can enlarge when you hit them with heat (air expands when heated).

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That wouldn't have been my tip. I don't wick anything off and don't use a spatula. But I'm sure it's fine if you want to do it that way.

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Steve, when you cut the wrap away, what did you see? Did it peel off really easy? Did it look like the threads beneath didn't see a lot of the "solids" in a CP?

Mike,
I just cut it down the center and peeled it off. It did come off pretty easy but it does look like there were some solids left on the rod. When I applied the finish I made sure there were bubbles by hitting it with a little heat. The bubbles came later. I'm thinking I may have not soaked the threads enough. I put enough on to make the threads turn dark. May need to put on a little heavier coat.

Its all about getting the CP ....INTO the madeira.

I use A LOT of Madiera and until recently I have been doing the CP thing TOTALLY WRONG...That was causing the problems. I use acrylic cp and the secret with it is to only use enough to wet the threads and that is IT. Add additional coats if needed but the first application should only uniformly wet the threads. Any excess (I tend to still be a bit heavy handed) can be carefully removed with a coffee filter.

At least, that is what works for me.

Derek L. McMaster
Rohnert Park, CA

Born to Fish, FORCED to Work

I think there's a tendency to use too much CP regardless of what brand of thread or CP you're using. Everyone wants to totally soak the threads in it, and then watch as the stuff dries and the color comes back. We've found that a 'light", even, smooth coat is best.

The other thing folks do sometimes is use the heat gun before they really need to. The original idea was to bring bubbles to the surface where they would pop or could be popped. But actually, heating can cause air bubbles where there would otherwise not have been any. I think the way it's supposed to go is to put the finish on (this goes for epoxy, too) and spin it for a while (somewhere between 6rpm, 11 rpm, or way higher, depending on which school of thought you subscribe to) and then stop to see if there are any bubbles. If there are, you can pop them at this point, and can also use some heat to bring up the rest if there are more. Heat is not a "standard" part of the process, at least for me.

Uncle Russ



Edited 1 time(s). Last edit at 07/24/2006 11:58PM by Russ Pollack.