Honey, Your jig's on fire!

"wright1902glider" wrote in message
...
| For the past few days, I've been working on a project that is semi-
| related to aviation. That is, its related by the fact that the skills
| necessary to complete it may also be usefull in building an aircraft.
| I like to think of it as a training project.
|
| What I'm building is a kinetic-sculpture racing vehicle. By
| definition, its a whacky-looking multi-wheeled craft powered only by
| humans that will be capable of traversing roads, trails, sand, mud,
| and small lakes. These crafts also have an artistic theme, but that's
| not really important. The real issue is that my craft is being
| constructed of welded steel tubing. In that respect, the skills
| required are exactly the same as those needed to build a steel-tube
| fusalage (sp?? never could spell)
|
| So, following in the great tradition or Anthony Fokker, I spent the
| past few days laying out a design on a sheet of particle board,
| attaching pine blocking, and cutting tubes to fit. I've made good use
| of the H-F tubing notcher. BTW, the arbor on mine likes Vermont
| American and DeWalt hole-saws, but not Lennox. I've also descovered
| that my notcher can't really cut an angle greater than about 25
| degrees on 1 1/4" tubing. So I've been using Tubemiter and the
tripple-
| cut ******* file that my Dad to left me as well. Fitting tubing for
| this type of project isn't critical, so its a good way to practice
| without getting dead. The type of tubing isn't critical either. I've
| been using EMT since its cheap and easy to obtain from the Borgs.
| Since the stuff is always slathered in zinc, I've built an "acid tank"
| which is nothing more than 4' of 1 1/2" PVC with one end capped off.
| Fill 3/4 full with a 20% solution of muratic acid and water, insert
| steel tube, no smoking for 20 minutes, rinse. (Remember, I'm making
| art here. I'd never use EMT in an aircraft. I've seen what's under the
| zinc.)
|
| Then come the two fun parts. Fitting everything back together, and
| keeping it aligned long enough to tack weld the joints. I'm using an
H-
| F torch, this time with the #2 tip. I fire up the torch, adjust, start
| heating the tubes focusing intensely on the joint when I hear "Honey,
| your jig's on fire!"
|
| Yes dear, that happens to wood when you point a 6300 degree fire at
| it. Yes, that's OK. Yes, I planned on it. YES, I DO have a big bucket
| of water, and a hose, and a fire extinguisher.
|
| I still suck at welding, but I am getting better. Next weekend's
| lesson is in gymnastic welding and warpage. Should be fun.
|
| Harry Frey

Sounds like fun! FWIW, I remember reading about a guy in Alaska building
a Bush Plane using EMT in the early 1980's. He flew it, for how long he
flew it I do not know. G

--
Anyolmouse