white spots again

[Harryvan]

For those who use a thin coat first do you use one or more? Seems like several coats might fill pores and prevent what I assume to be white residue from pads.

Can CA go bad over a 6-12 month period? Can too much accelerator also cause white spots?

 

[d_bondi]

I have been using StarBond Super Thin (2-3 Cps) for my first coats and usually put 4 coats on. I do it with the lathe running around 300-400 rpm, and apply to the top of the rotating blank with a small section of folded blue shop towel underneath smoothing and taking off excess as I go. Edit: Just a very light spritz of accelerator between coats, it doesn't take much. If you can wait and let it dry/cure naturally, that is even better. I usually don't have the patience.

Yes, CA can go bad especially if you get moisture in it. I don't know about all CA, but StarBond specifically guarantees their materials for 24-30 months if you keep it refrigerated.

I have heard so many good things about GluBoost, here on the IAP, I just ordered some to give it a try. It is a CA product that is specifically designed to be a finish. I did note on GluBoost's site that they say NOT to refrigerate their products once opened.

I'm sure you will get better feedback/advise on your question if you can provide a few pictures of what you are experiencing.

 

[JohnU]

The accelerator can cause spots in some ca's. I used to have them issue until switching to Gluboost. Their fill and finish blue, orange and teal labeled bottles are a flexible finish and I haven't had any issues. The teal bottle is "ultra thin" and wicks in to seal pours. The orange is the "thin" and the blue label is the "medium".

 

[Hippie3180]

My understanding is that white spots can also be trapped moisture. CA does not like moisture. The other possibility is that there was still some sanding dust somewhere.

 

[jrista]

For those who use a thin coat first do you use one or more? Seems like several coats might fill pores and prevent what I assume to be white residue from pads.

Can CA go bad over a 6-12 month period? Can too much accelerator also cause white spots?

Just curious...what kind of applicator are you using?

When I first switched to GluBoost, I had some problems. One of them was the foam applicators I was using. Something about this particular foam, seemed to create white frost like stuff on the finish. I was told, guaranteed, it was moisture, but I was able to repeat the issue under very low humidity conditions. I have a lot of this foam, so I've resorted to bonding some wax paper to it, to keep the foam from coming into contact with the CA. Once I finish this foam off, I'll be looking for an alternative foam. Something closed cell, that I could just put the CA on directly, would be idea, bonding the wax paper is a paint...but, it did resolve my particular problem.

I've had some very slight milkiness on a couple of occasions, that I've only been able to attribute to humidity...but it took fairly high humidity to cause it.

The interesting thing is, CA actually NEEDS moisture to properly cure...it just can't be too much. Without enough humidity, CA would cure fairly slowly. So it needs a bit, as its the water that catalyzes its curing reaction. Too much and it seems like the reaction can, for lack of a better way of describe it, sort of "boil over" which causes the whitening.

The biggest issue I've had with white spots or frosting, though, has been the foam I've used. I don't know if other materials could cause the same issue, but, its something to consider. I know that my foam IS the issue because I've had it at humidity's ranging as low as 16% to as high as 70%, and humidity did not seem to play a role in the effect regardless.

 

[leehljp]

Temperature can also a part of the equation. My experience has been that below 75° - 78° degrees, the chemical reaction of CA curing will draw in moisture - or maybe some other reason, but the fact is - it doesn't happen nearly as much in 80° and above.

Below is a pict of a duck call made many years ago. I put a fairly thick layer of CA on it an let it sit overnight in an unheated shop in which the temp was mid 60° range. I left the shop almost immediately and did not watch the curing. I was surprised the next morning. The "frost" (white) sanded off immediately. The white spots for me, in general, were below the surface and had a couple of different causes. But in the end, most of the time it was in combination of temperature lower than 75° or close to that.

Imported Photo from leehljp

Imported Photo from leehljp. Please edit title and description.

www.penturners.org

Imported Photo from leehljp

Imported Photo from leehljp. Please edit title and description.

www.penturners.org

 

[wouldentu2?]

I use only thin CA, 5 initial costs then a light sand with wet 800 paper to show low spots, then usually several more if the grain is filled. I wipe it off with DNA after sanding. Hundreds of pens with no problems.

 

[rixstix]

Temperature can also a part of the equation. My experience has been that below 75° - 78° degrees, the chemical reaction of CA curing will draw in moisture - or maybe some other reason, but the fact is - it doesn't happen nearly as much in 80° and above.

TNX Hank,

Well, that would explain all my failed attempts with the finish even following the expert tutorials. Now I can quit wasting time & money trying. Year round temp in the downstairs living area is low 60s. MBR is mid 50s.

 

[jrista]

TNX Hank,

Well, that would explain all my failed attempts with the finish even following the expert tutorials. Now I can quit wasting time & money trying. Year round temp in the downstairs living area is low 60s. MBR is mid 50s.

I wouldn't give up just yet. I've had success with GluBoost in cooler temps like you have. CA is much less temperature dependent than humidity dependent.

Also, just to make sure its understood, the curing of CA glue is in fact RELYANT on moisture. Without moisture, it won't cure...in fact, within a bottle, the general idea is that you want to keep the air as dry as possible to make sure the stabilizers in the glue don't catalyze within the bottle (i.e. put the cap back on as fast as you can.)

The process of curing is actually an outside-in process. Moisture on the surface you are bonding, as well as moisture within the air, will catalyze the reaction from both surfaces, inward towards the middle of the layer. The curing process will release both water vapor (which will in part deposit a small amount of moisture on the surface of the CA coat you just put down, which is in fact quite important for the next coat!) as well as formaldehyde (which is the crap that stings your eyes, and that's actually really bad, so try to avoid getting the fumes in your eyes!)

Temperatures cooler than 75 degrees might be problematic, at certain humidity levels, or maybe certain dewpoints. I don't know that there is any explicit temperature at which moisture suddenly becomes more of a problem, WITHOUT a link to the ambient humidity as well.

Too much moisture or too high of humidity, and the curing reaction can happen too fast. This can cause rippling of the surface if its just a bit out of balance, or it can cause frosting if its more widely out of balance. So you do want to avoid too much moisture. I've also encountered frosting that seemed to have nothing to do with humidity at all and may have been due to other chemicals in the applicator I was using (at one point I thought it may have been water in the foam, but the foam seemed to have some kind of very thin film of some kind of chemical on it, which I think was the actual problem.)

Anyway, I was curious what kind of applicator you were using before. It may be the applicator. It may also depend on the kind of glue. I didn't have great luck with other CA glues I tried using in the past. I switched to GluBoost middle of last year. Orginally had some issues, which may have been due to bad bottles, and maybe the applicators I was using. Once I sorted that out, I've been a fan. Being rather allergic to CA fumes, and not really a fan of CA in general, I have to say that I've been pleasantly surprised with the quality of GluBoost's formulation. Much lower odor, which in general seems to lower the risk of being exposed to its fumes, and it just seems to produce a nicer quality finish easier.

 

[rixstix]

Jon,

I've used quite a few different applicators. It shouldn't be rocket science. I've followed the expert tuturials which have no temp or humidity disclaimers. I am pretty sure it is local environmental conditions and/or my lack of patience.

Gluboost here. Old and fresh. Similar results. Orange peel.
Basement living area: 65 degrees, 45% humidity winter conditions. Humidity goes up to 75% in the summer, same temp.

 

[jrista]

Jon,

I've used quite a few different applicators. It shouldn't be rocket science. I've followed the expert tuturials which have no temp or humidity disclaimers. I am pretty sure it is local environmental conditions and/or my lack of patience.

Gluboost here. Old and fresh. Similar results. Orange peel.
Basement living area: 65 degrees, 45% humidity winter conditions. Humidity goes up to 75% in the summer, same temp.

I have run into the orange peel issue as well. Something that I think has been more common with GC than other CA glues, at least from my experience.

The only thing I've been able to do to avoid the orange peel (which I'm assuming is a bit different from the frosting...instead of the white frost, its that rippled, wrinkled surface?) is to use thinner coats. I've had the orange peel/wrinkled skin both with and without the accelerator. It seems to be worse when I have a thicker coat. Only data point I have to offer there.

 

[Harryvan]

Thank you all for your responses. Will get around to finishing a few pens this week--twelve on order- and let you know. Never ave this problem on acrylics--just wood and mostly open pore. Thanks again to all who responded