Building My House

I have always wanted to build my own house. I am retired now, so I have the time. I found some land, designed a house that would fit the land and my needs and got started. I am doing all the work myself, so progress will be fairly slow. To read this blog from the beginning, start with the oldest archive and read posts from last to first.

Saturday, May 29, 2010

72: Compressor Adventures 1

I have a small Craftsman compressor that puts out about 6 cfm. Okay says self, we need 4 more cfm and we’re all set. So, I google the subject “manifolding (connecting) compressors together” and I get several positive responses. The articles say it’s done all the time. So, I borrow a friends compressor (also a Craftsman , but a littler larger) and buy some air hose and fittings to connect the outputs together. Everything looks pretty slick. My compressor needs are solved for very few dollars. If only it could be that simple.

Long, story short, the foam doesn’t spray. I mash the trigger and the foam doesn’t even make it all the way down the mixing tube before it stops. Needless to say it doesn’t spray. Canister 1 is lost. I’m sitting there wondering what’s wrong (as the two components backflow and start mixing together inside the canisters). Remember this stuff expands when it mixes. I get the canister out of the gun and set it on the floor (bad move) – this is why you need box #2. It keeps expanding and eventually pushes the plunger partly out the back end of the canister. Now the unused part A is spraying all over the place, a stream of stinky, brown goo arcing 20 feet across the inside of my house, hitting walls, windows, window screens, my work table, darn near everything in sight. I finally throw a rag over it and pitch it all out the window, where it finally empties, but not before it has decorated the inside of my house with part A; the resin component that has a medium strong chemical odor.

So, it’s open up all the windows that weren’t already open and then off to the phone to call Soythane technical support. Fortunately, it’s a 1-800 number cause I’ve used it plenty. Tech support guy says he’s never heard of connecting two compressors together and that they use a Campbell Hausfeld 80 gallon 5hp 210 volt compressor for all their test spraying. Hey, that’s a big compressor, lots bigger than my tiny little Craftsman. How do I know this, because while I was looking for airhose and fittings, I also looked at all the compressors for sale at Lowes. Their biggest is an 80 gallon Kobalt for $799, but it only puts out slightly more than 10 cfm at 100 psi. Further, it says peak horsepower of about 5, but running horsepower of about 4. Self says, I don’t want to spend this much money, especially if it is going to just barely get out 10 cfm.

So, I call up the local rental place to see what they have in the way of compressors. Sure enough, they have this big mama; gasoline powered, 11 hp, Honda engine, with a pump the size of a beach ball. It puts out 25 cfm at 175 psi, so self says to self…problem solved. It’s so heavy that I’d never get it out of the pickup truck, so they deliver it to me on a truck with a liftgate. It goes for $215 per week (so much for cheap compressor solutions). I get it delivered that afternoon, expecting to spray foam the next day.

Learning opportunity #1 – the weather forecast the next couple of days is highs of 75 degrees. Shame on me for not checking the forecast first. Beautiful weather to work on a house, but not to spray foam because this stuff needs 80 degrees (or warmer) to cure right. In fact the company says use the 80-80-80 rule. 80 degree material temperature, 80 degree substrate temperature (the surface you’re spraying it on) and 80 degree air temp. Higher temps are okay, lower temps are not, better to wait for warmer weather. Great, the clock is running on this rental compressor and I can’t even use it.

But, somehow the planets align. The very next day even though it’s only 75 outside, the sun shining on my metal roof warms the metal up to a “comfy” 130 degrees. How do I know this, they recommend buying one of those laser infrared thermometers, about $30 to $50 at Harbor Freight or Sears. The roof warms the air inside the house up to about 85. Great, all I’ve got to do is warm the foam up to 80 and we’re in luck. Tech support gave me several ideas on how to warm canisters, but sitting them in the sun is the easiest. Hint: if you set them in the sun, they don’t need to be there very long. Five minutes is plenty, 15 minutes and they are at 95 degrees; too hot to spray foam with, as the foam will both mix and cure in the mixing tube at that temp, clogging the gun and losing yet another canister of foam. Use 90 degrees as a max for foam temp. Above that, cool them before use. Better yet, don’t leave them out in the sun too long. If the canisters are 80 – 85, go for it.

We have a ways to go yet, so I’ll continue in next post.


At 3:09 PM, Blogger Tony said...

About the stinky stuff (part A) all over the house; it actually dries out in a couple of days; and once dry, it doesn't stink anymore. Nor is it slippery, or even very visible.


Post a Comment

<< Home