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Jeff Moffett
03-06-2007, 4:28 PM
I've watched turning demonstrations where some CA and accelerator are applied to a blank on the lathe, and the demonstrator is able to continue turning almost immediately. On several occasions recently, I have discovered a crack in a blank, so I typically douse it with thin CA followed by medium CA and accelerator. I've even waited about 10 minutes to give the CA time to cure, but when I turn my lathe back on, I see drops of CA that have spun off the blank onto the bed of my lathe. In other instances, the CA appears to be dry, but as soon as I make a pass with the roughing gouge, wet CA comes flying out.

Here are some of the questions rolling around in my head: How long do I have to wait to ensure the CA is dry? Shouldn't the accelerator instantly cure the CA? Should I be applying the accelerator to the blank before I apply the CA? Does older CA take longer to cure? Does older accelerator not work as effectively? Any tips are greatly appreciated!

Lee DeRaud
03-06-2007, 4:35 PM
It dries from the outside in...sounds like the medium CA is shielding the thin CA from the accelerator. I would skip the medium altogether unless you really need the gap-filling properties.

Dario Octaviano
03-06-2007, 4:35 PM
CA have different thickness. The thicker ones cure slower.

Curing is affected by moisture and temperature. Cold slows it down tremendously even with accelerator.

This is only through my experience.

Frank Kobilsek
03-06-2007, 5:06 PM
Jeff,
You would not have asked about old CA if that was not your worry and you are correct in your worry. Old CA does cure slow if at all. Maybe like Lee said just use the thin. Sand or turn off excess. If you need more fill then add thick. Old CA haunted me for a while before I smartened up.

Oh, just because you just bought it doesn't mean its fresh. I bought a bottle of thick one time and it would not cure in days. Get it from someone you trust on line or from a shop you know to have good traffic on the stuff.

$20 solves this problem

Frank

John W. Willis
03-06-2007, 8:34 PM
I saw one demo where the CA accelerater was applied to the crack and then the CA was dropped in? :confused:

Kevin McPeek
03-06-2007, 11:31 PM
I was thinking I had some old CA from some similar instances then I found out that it cured quite quickly between my finger and the piece. I had to take the piece out of the chuck to reach my debonder, glad no one was around to see that one. I usually just give more time now days.

Glenn Hodges
03-07-2007, 7:44 AM
I am a slow learner, but learned to put a small amount of CA glue, then accelerator, then more glue, then accelerator.

Wayne Bitting
03-07-2007, 7:50 AM
I had a similar problem with CA. After hours it wouldn't cure. A fellow Creeker said it was humidity related (cold dry winter months). Stuck a humidifier in the shop the night before and the next day I had no problems with the CA kicking.

George Tokarev
03-07-2007, 9:56 AM
You don't mention, but putting it inside doesn't stop it from working its way through to the outside, even if you apply some accelerant. The thin is the way to go on first application, in my experience. Wicks its way into places you don't even know exist. Smart money puts a masking tape "dam" on the outside where you might suspect it's deep enough to matter.

Acid woods cure slowly, and when the crack is deep, isolated from the air, even slower still. That's where a dash of accelerant applied in advance to sweeten the area comes in. It'll wick in a bit and give you a thicker skin, as well as help the surface flash cure and limit penetration and the ugly CA shadow that can give you. Not sure what wood you were using.

Maybe CA doesn't last long enough around here, but when it gets old, my problem has not been lack of cure, but full cure! I keep sealed bottles refrigerated, as common wisdom suggests, and leave the opened ones sans tops.

Jeff Moffett
03-07-2007, 10:42 AM
Thanks for all the tips, everyone. I suspect my issue is a combination of factors: cold/dry garage shop, old CA, and insufficient amounts of accelerator. I'll add a humidifier to my shop, buy some new CA, and try the accelerator/CA/accelerator/CA/accelerator approach.

BTW, the latest episode occurred with a piece of hedge/osage orange, but I've experienced it with several types of wood. Thanks again for all the great replies.