CA Issue

[G1Pens]

I have been having very good luck with CA until just recently. The last couple of pens I have done that I did a CA finish on have been a real pain. What has been happening is that after applying the CA everything looks fine, but as I MM to a shine it starts developing the ghosting. It is usually only in a couple of spots and usually shows up after the first two or three levels of the MM. I can strip it down to bare wood, go thru the process again and it may happen again. If it does, it is in the same general area on the pen. Usually the third time is a charm, but doing a finish 3 times to get a good one is a real waste of time.

It has happened with just CA and with CA/BLO. I have tried wiping down the blank with DNA and tonight it happened when I wiped down with Accelerator first. It has happened with Koa and with Yellow Pine. So, I can't seem to find a pattern.

I am using the same CA I have always used (Monty's). I don't use accelerator during the CA application (other than the initial wipe down). I wet sand at low speed so I don't think there is a heat build up.

What else could be causing this?.....or is it just a string of bad luck?

 

[LeeR]

I've only done one CA finish, so I am by no means an expert, but I've used CA for years in model building. I'd tend to say maybe the inner layers were not fully cured. I started with several thin CA coats, and then started layers of thick. I let each layer on my pen dry for maybe 10-15 minutes (I only had thick, so I wanted to make sure it was pretty hard.) Then I let the blank cure overnight before doing any MM polishing.

I was amazed at how well this method worked -- I was prepared to have to go thru a few pens to get it right, but this method seemed to work pretty well.

You might give it a try. I also did not use accelerator, but prefer to let the CA cure on its own. I've had CA finishes blush on models, but then again, the CA gets sanded, and becomes hidden during the priming and painting steps.

 

[PenMan1]

Gary:
The common denominator here us that the woods you mentioned are both very "pitchy" or oily woods. With woods like heart pine, cocobolo, purpleheart and many others, it is essential to "dry out" these gains before sealing in the moisture.

The best remedy that I have found fix this problem is to aggressive wipe the finish sanded barrel with SEVERAL coats of CA accelerator before applying the CA finish. Additionally on these woods, I omit the BLO from the finish.

I'd rather waste a little cheap Accelerator rather than re-sanding and refinishing.

I hope this helps.

 

[G1Pens]

Thanks for the advice. I'll try using more accelerator.

Can anyone explain why it is not noticeable until I get into the MM process?

 

[PenMan1]

Likely (or at least in my experience) the heat generated in the polishing process draws the remaining moisture to the surface. This is what was happening with me and I am just guessing that it is your problem as well.

This would also explain why the ghosting reappears in the same spot
There are other possible explanations, but from your description it seems like the most likely cause.

 

[PenMan1]

Go back to your exact finish process with a "dry" or less oily wood. If your perfect finish returns, that could help with diagnosing the problem.

FWIW: with cocobolo, purpleheart and BOW, I'll finish sand, apply accelerator, wait overnight, apply more accelerator then finish. Oily and pitchy woods can be a booger to CA finish.

 

[G1Pens]

Oddly, I have done several Cocobolo pens and have never had a problem with that wood. But I knew it was an oily wood and wiped it down three or for times before applying any CA.

In a somewhat related question.....and this may be a stupid question....could I use a wipe on poly as a first coat to seal the wood and then complete the finish with CA?

 

[PenMan1]

I don't know about wipe on poly, but some here us a "sanding sealer" before CA finishing.

My guess would be that WOP would be too "slick" and cause CA adhesion problems?

This is one of those times I really miss Russ Fairfield. He would have 10 or 15 very "workable" solutions!

 

[1080Wayne]

If by `ghosting` you mean an area of the blank where sanding dust preferentially adheres , you have sanded through the finish at that point . The wood underneath has more electrostatic attraction for the CA dust than does the CA finish . When the barrel is not perfectly round (which is very common) , a thinner CA coat is applied to the high spots , and is sanded off quicker .

 

[G1Pens]

If by `ghosting` you mean an area of the blank where sanding dust preferentially adheres , you have sanded through the finish at that point . The wood underneath has more electrostatic attraction for the CA dust than does the CA finish . When the barrel is not perfectly round (which is very common) , a thinner CA coat is applied to the high spots , and is sanded off quicker .

This is something different. It is more like the CA has separated from the wood creating an "air pocket" underneath the CA.