03-21-00

A lesson in Butane.

After I had made my first 5 or 6 runs with Ruby I was pretty happy.  It was running good and I had read that with time my run times would get better.  My average run time had been 10 or 11 minutes.  But as time went by Ruby was becoming more sluggish and my run times were dropping off dramatically.  Then a few days ago I was out late in the garage and I decided to give Ruby a run before hitting the sack.  I have a small 18 foot oval on the floor and Ruby could not even make one complete circle.  It was acting very sluggish, blowing lots of water and just did not have any power.

So I started asking questions on-line.  I used a compressor to do a pressure test of the safety value but no problem there.  I cleaned out the gas jet but still nothing.  I was beginning to think I would have to return it.

It turns out that Fred only lives 4 miles away so I made a stop last Saturday to get some insight into my problems.  We pressure tested again and the safety valve held up to about 35-40 pounds.  We checked for gas leaks but no problem there.  So we fired it up on the bench, built up some steam and then placed it on the track.  Sure enough, it ran for about 15 minutes non-stop!  It reminds me of taking my car in for a problem but when you are at the shop the car works fine.

We talked for a while and then Fred mentioned something I had not heard about.  Butane, which is what Ruby runs on, does not do well in temperatures around 50 or below.  Isobutane will handle it a little colder but the outside temperature really makes a difference on how well a steam engine runs.  

Well, sure enough, the temperature down on the garage floor stays in the 40-50 degree range.  I have a heater in the garage set to 70 but there is no circulation.  I can vouch for that because my feet get cold in the winter when I am working out there.  So on Sunday I set the temperature to 75 and turned an oscillating fan on, pointed at the floor.  After working on me Depot for a few hours I fired up Ruby.  It ran for 14 minutes without a problem.  See when I first got Ruby it was in the 60s that week so all my runs were good.  Then as the weather changed to the 30s and 40s, my run times got worse and worse.

So there is my first piece of advice for a steam novice like myself.  Isobutane works better for  temperatures down to about 40 and butane should only be used when the temperature is 55 or higher.  I have yet to try Isobutane but I'll note on the site how it works on my cold garage floor.

So if your not asleep yet from my writing, check back for more on Ruby, the layout, hand laid track and scratch built buildings.  Special thanks to Fred for taking the time to teach me a few things.

Take care and good steaming,

Johnny F.