CA Finish peeling on inserts

[Kirk Malmo]

I've finally started making some quality sounding inserts, but I can't seem to get a CA finish to hold up.

The attached picture shows my problem with the CA finish peeling at the edges where I cut the inserts. The piece of paper is wedged between the peeling CA and the wood.

I have let the wood settle for several days or longer after turning, so it shouldn't be a shrinking problem. I sand the whole insert to 800 grit, allow to settle, then apply 3-4 coats thin CA (first 1 or 2 coats I don't use accelerator) then 3-8 coats medium CA then sand back to 1500. I have used BLO on the inserts before or after applying finish and doesn't seem to make a difference either way. (Saw a pen turner put BLO on paper towel before putting CA on it which was neat, but didn't help either).

I finish with CA before drilling. Could the heat from drilling cause the wood to swell and loosen the finish? There are no visible signs of cracking or stress or clouding on the finish after drilling and before cutting.

I know some guys might say to just finish the external part of the insert that sticks out of the barrel, but I don't like the way that looks. I've seen calls with the whole insert finished, so I know its possible to make it work.

Any suggestions? Something I'm doing is not allowing it to stick properly to the wood. Yes, some woods are worse than others, but the one in the picture is persimmon so it shouldn't be an oily wood problem.

Thanks for the help.

[majordog]

Thats a new one on me....I have never seen CA peel like that.  Interested in the feedback you get on this one.

[ben]

Actually I do not have a clue because I have been using CA for years and never had the problem. Might ask what wood you are using since it should not make any difference, oily wood such as cocobolo might use a wipe of alcohol to get rid of some of the oil but I do not do that either. I really do not think using thin ca to start with would be a problem, but I have always used medium 8 to 10 coats sand out the marks left from applying the ca and buff. I always finish the insert before I drill it. I put it in a collet chuck for the drilling.
Brand of ca should not make any difference but some do work better than others me I use EZ bond. That leads down to try a different ca as you may have gotten hold of some bad ca. I also use accelerator but you don't have to it just takes a little longer to apply more since what you just put on takes longer to dry.

Hope this helps some anyway.


ben

 

[Kirk Malmo]

What are the generally accepted parameters for applying a CA finish as far as temperature and humidity go? I can't remember exactly when I did these, but I know I spent some rainy and cold days in the shop recently. This is not the first time I have had this problem, but maybe it is a coincidence that I choose to do finishes on the worst weather days.

[wingshooter]

I’ve had same problem in past all with on oily side woods some I’ve just used thin ca others I wiped with acetone and it did good or wiped with teak oil that pulled oil too

[Andrew of HaddenHailers]

I literally did this last night, but not on the tone board.  I was perplexed like you when I read yesterday but just so happened I had a glob of ca on the inside of my exhaust I didn't like.  So I took my stepless reamer and took all of the ca from the inside out.  Right at the edge of where the ca was still intact, it started to pop and come lose, just like your picture, but different area.

I suspect your problem is heat.  I personally don't ca my insert tenon, so I haven't had this issue on it.

I hope that helps.

Andrew

[s wuebber]

You say you’re applying ca then drilling...have you tried to drill then CA.
How quickly does the release occur, can you experiment with some scraps of wood and get different results. I’ve recently read some building tips on balsa for another hobby I have. It emphasized use of fresh CA. I don’t know if old or fresh makes a Difference but may be worthwhile to consider.
Could moisture content be a factor?