CA Finish Problem

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David350

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Sep 10, 2017
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Just when I think I have it figured out, I have another CA finish problem. This problem is that I get small, maybe small, irregular pea-sized or so areas, usually only one or maybe 2 spots where the CA finish looks as if the color of the wood is bleached underneath it. Is this an artifact of applying too much activator? I use the stickfast thin for 5 coats, then the medium for 5 coats, then a couple more thin just to fill in any medium voids. I usually pulse 4 to 5 shots of the activator in between coats. I then wet sand with the micro pads, 800 to 12,000. Thanks in advance for any suggestions. David
 
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RKB

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Mar 17, 2014
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Apollo, PA
I feel your pain, I have had that happen to me. Some things I did were: I switched to another brand of CA, BS Gold, and I make sure to wipe down my blank with acetone before application of the CA and I stopped wet sanding my wood blanks.
Hope you find a method that works for you. :biggrin:

Rod
 

thawkins87

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May 15, 2017
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McKinney, TX
I gave up on Stickfast CA glue. Have had all kinds of problems with it and decided I'm going to find another brand. That being said, you probably don't need that many shots of activator, but I don't know that it would create the particular problem you're having.
 

jimm1

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Dec 30, 2006
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Thompson's Station, Tennessee, USA.
I'm with Tim Hawkins on this one. I also moved away from stickfast. I now use Mercury CA. Check out Robert Kulp at Tennessee Pen Supply on Facebook or www.tennesseepensupply.com.




I gave up on Stickfast CA glue. Have had all kinds of problems with it and decided I'm going to find another brand. That being said, you probably don't need that many shots of activator, but I don't know that it would create the particular problem you're having.
 

DJBPenmaker

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Nov 10, 2016
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Cheshire, UK
Denatured alcohol clean first and let it dry thoroughly. It might be too much activator. I use the aerosol type and only ever apply two very very short puffs or one and from a distance of at least 9 inches or so. I never wet sand when using CA on wood.

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leehljp

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Feb 6, 2005
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Tunica, MS,
Just when I think I have it figured out, I have another CA finish problem. This problem is that I get small, maybe small, irregular pea-sized or so areas, usually only one or maybe 2 spots where the CA finish looks as if the color of the wood is bleached underneath it. Is this an artifact of applying too much activator? I use the stickfast thin for 5 coats, then the medium for 5 coats, then a couple more thin just to fill in any medium voids. I usually pulse 4 to 5 shots of the activator in between coats. I then wet sand with the micro pads, 800 to 12,000. Thanks in advance for any suggestions. David
I can duplicate that on several species of wood with a specific technique: Cover with CA well, sand smooth, sand through and add another coat. On some woods, the sand through (sand through the CA to the wood in a spot) and re-cover with CA. Suddenly, or later, that spot will show through. The "sand through" is often a product of slightly out of round or non concentric turning. That happens from several reasons related to mandrels - bent, tail stock too tight, not using 60° live center on the mandrel, too much pressure in sanding etc. Early on, it was not uncommon to get bushings that were drilled off center minutely. High spots, or other can cause sanding through the CA in a spot. Recoating with fresh CA makes that light spot develop fast on some and later on others.

This is not to say that this is your cause, but it was no uncommon a while back.

Activator, moisture and even certain types of CA might be part or all of the problem. In the past, when I had a sand through (It showed the most on Olivewood for me) I had to go ahead and turn ALL of the CA off and start fresh in order to keep the pea size light spots from showing.
 
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magpens

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Coquitlam, BC, Canada
Not sure I have an answer. . However, I would be wary of wet polishing DURING the overall CA application process.

Also, rather than micromeshing during the process I sand fairly lightly with 320 or 400.

After the CA application is finished I sand starting at 240 working up to 2000 ... no micromesh. Again, I do not wet the sandpaper.

For me, the CA goes on in a somewhat "ridgy" fashion ... that's the reason for dropping down to 240 grit to get the surface smooth.

I find that I have to sand at 240 and 320 until all shiny spots are gone and this can take a while. . After that, the sanding goes quite quickly but I sand lengthwise with each successive grit for about 40 - 80 strokes before moving on to the next higher grit. . No water, but, if you promise not to tell .... a little bit of spit !
 

David350

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It doesn't appear to be sanding through the CA as it still looks very shiny and glossy on the lighter spots...

I'll try dry sanding and see if my luck improves. Thanks everyone, David
 

leehljp

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It doesn't appear to be sanding through the CA as it still looks very shiny and glossy on the lighter spots...

I'll try dry sanding and see if my luck improves. Thanks everyone, David
David,
Sanding through doesn't mean that it has been left that way. Often with the first two or three coats, one stops and sands the top coat smooth and then applies another coat on top of that. DURING this process of sanding the first two or thee coats, there is sand through, and it is not really noticeable unless you know what it is, and know what to look for. At this point, you will add an additional coating of CA or maybe two or three coats. Theses additional CA coats will be shiny, but they reveal that spot that was sanded through earlier, but later covered by more CA.

Sand through spots allow moisture or heat in or out through that spot, more so than where it is totally covered with CA. I am not a chemist or an expert; What I wrote may not be technically correct. But I have noticed on quite a few occasions, that a pea sized sand through creates a light spot. I have asked and wondered why. It was finished with the same finish as the rest of the wood. The only plausible explanation that I could come up with was that the open spot (sand through) was different color because it was a sand through and open to ambient air different from the rest of the pen.

I can and have (in the past) replicated that with predictable outcome just to learn from it. That is what normally happens. The spot really shows up later after you have covered it with more coats.
 

MRDucks2

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Jul 17, 2017
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Franklin, IN
I have learned to notice sand through. I wipe the blank with denatured alcohol, usually every 3 grits of MM. Previously I used acetone to wipe and have found that the sand through spots were more pronounced with acetone than DA. Now I only use acetone if I am trying to repair a CA finish or on plastics.


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