Silicone seam sealing question

Maybe you used to much thinner? My silicone dried almost before I could smear it with my finger; and cured in a few hours. I used no thinner at all.

Did you use Mineral Spirits? Ron at Six Moon Designs recommends a 1:1 mixture of GE Silcon II to Mineral Spirits and then using a paint stirrer designed for use on an electric drill to make sure you get it completely mixed and even consistancy.

I just sealed my Tarptent Contrail an hour ago; I mixed mineral spirits slowly, not at all the 1:2 mixture that the TT instructions suggest, until it looked less viscous enough to paint with (perhaps denser than needed, but at 1.5 pounds, I'd like the extra silicone insurance :-p). I just checked the seams outside and they're already getting tacky…it's sunny, about 70° and 14mph winds, and I set up the Contrail's door /into/ the wind to facilitate drying.

I have no idea what's going on with my sealing…The undiluted spillage from the GE Silicone II tube won't even dry on the caulk gun, nearly two days later.

I went out and got some sil-net, wiped the previously coated seams as clean as I could and recoated it…dried almost instantly.

What the @#@!???

Edit: I just talked with Henry Shires and he said he's seen this happen before- he thought it's quite possibly due to a bad tube of silicone from the hardware store.

Over the years I found several tubes of silicone that did not set up. In my case they all had one thing in common: they were 1+ years old. And that was using undiluted for chaulking. If you bought the tube at a busy store I would not think that the shelf life had expired. I would buy another tube and try it again. Use only enough mineral spirits to make the thinnest workable mixture.

You may have a sticky mess that you have to scape off and wipe off with some more mineral spirits before starting over. A bummer on a new piece of equipment.

Ken

Just out of curiosity, is there a reason that Silicone would be better than Silnet? Having painted and worked with all sorts of caulking products, I would have to say that it is very common to end up with bad tubes…no matter what the product grade/cost or material. It must be something with shelf life as well as the fact that they are prone to not being 100% sealed…with the obvious need to have a moving bottom.

I would hesitate before applying mineral spirits to delicate nylons or any kind of NEW piece of equipment. That's just me though…I stick with what has worked…and Silnet seems to work fantastic.

Henry Shires seemed to think it had to do with being too old as well. I purchased it from Home Depot- you'd think they'd move enough product to not have too much old stuff around.
I don't think the GE Silicone is necessarily better than Sil-Net, just way cheaper.
Anyhow, problem's solved now. Thanks everyone.

Glad things worked out for you, Craig. It is recommended that you only use "odorless" mineral spirits so that you aren't stuck with a tent stinking of petroleum. This is commonly available at hardware stores and it's worked well for me.