Re: Painting in high humidity
Originally posted by jsfinn:<br /> That hydro does look like a lot of fun!
Thanks.<br /><br />It took about a year to build, and is a hoot to drive. There's still a lot of set up work to do on engine position, tilt, finding the right prop, etc. but its up to about 80mph so far---- on flat water.<br /><br />Last week, I stuffed it. In rough water(2' swells or so with whitecaps), I went from watching the tach go past 5,000- which is almost 70mph, to being airborn,,,, then looking up at the surface of the lake and feeling my life vest lifting me up & out of it. All in about a millionth of a second. That was a rush..<br /><br />I figure my nerves will settle down in a few more days and I'll post the whole story on the 'Stupid Human Tricks' forum. <br /><br />......<br /><br />CC,<br />something that struck a cord:<br />If you were learning to paint in '73, I figure we're about the same age. In the Summer of 1973, I found myself in the Carolinas too, but at Parris Island wearing clothes that come in one size- 'too big', and holding a M-14. In the years since, I've had it pointed out that I'd starve to death as a Doctor, because my 'bedside manner' is horrible. As I mellow with age, I've come to realize how this poor bedside manner can be missinterpreted. <br /><br />..... On the paint thing:<br /><br />Slower solvents and hardeners than the present temp. would normally call for is the key to painting in high humity. That reduces the tendency 'blush'*****. Also, most modern generation urethanes are moisture cured. That means that humidity in the air aids and speeds up their 'flash time' and drying rates.<br /><br />*****<br />As paint dries, and the solvents evaporate,<br />the surface cools--- or absorbs heat like your beer can does. ONly the moisture doesn't accumulate only on the outside like a beer can. The paint film absorbs it from surface to the top.......... and makes the job turn white, or 'blush'. <br /><br />With fast solvents/hardeners, the paint film on your freshly sprayed '34 Ford cools, and gathers mositure (if it is avalable) from the air just like the side of your beer can does when you pull it from the ice chest. In one circumstance- all your efforts and expense is ruined. But with knowelge, experiance, and skill- it could come out OK too. <br /><br /><br />Another example:<br />if you have a run in a fresh paint job, and need to sand it out--- use a lot of water while doing it. You'll feel the paint harden more and more as you wet sand it.<br /><br />For a big run or whatever that will have to be redone- spray the darn thing with a water hose. It will kick right off and set. Then you can get to sanding it sooner. <br /><br /><br />But it is also a learned ability to guess or approximate how slow or how much to cut back on or increase various chemicals in the paint system to make it come out for the conditions of the day. Or, to realize which conditions can be overcome, which you can 'get by with', and which ya should wait to improve. <br /><br /><br />Over the years, in addition to I don't even know how many auto body shops, I have cultivated a few hundred customers, and members of car clubs who paint one or two cars a year. Usually it is some hot rod, 'Model A', a antique, or a classic they've built. At that level of experiance- I try to advise them to have every advantage going for them they can to help them along and avoid as much re-doing as possible. Like JS, they ain't doing this for a living, usually aren't in too big of a rush, and they just want their one or two projects every few years to come out right. I try to help out along those lines with their situation in mind. <br /><br />For the others who who seem to be in over their head's, and ask many many detailed questions, I try to answer them too, but sometimes have to tell them that after they've ruined about 6 paint jobs--- they'll get it all down pretty well. <br /><br />For everyone that sees this sort of work going on in less than ideal conditions--- ohh heck yeah it can be done. But you got to have your act together too. Like them guys that weld under water, it can be done, and done right, but not by the inexperianced.<br /><br />Ed.
