Thursday, October 17, 2013


After numerous unsatisfactory attempts to make adjustments to the settings of both ‘welders’ in the garage, the machine and myself, I needed a new piece of scrap to continue my slightly frustrating efforts at producing a consistently ‘good’ weld. I grabbed a drop off tube, cleaned the oily residue off of it, and ran the first weld bead. After finishing the weld, the glass on my auto-darkening helmet allowed me to once again see things other than sparks and molten metal. The first thing to catch my eye is the wisp of smoke twisting up from my steel work piece. Instantaneously my mind transports me just a minute or two back in time, as I was preparing the piece of tube. Instead of cleaning it off with acetone, as I normally would, I casually grabbed the can of brake cleaner that happened to be within arm’s reach. I sprayed the metal down and gave it a quick wipe with a paper towel, before setting it up on the table to begin my welding…Returning to the present, panic immediately sets in. Was the brake cleaner fully dried? Is that the normal smell from welding?? What’s that tingle in my lung?!?...

Now some people are acutely aware of the huge safety violation I just made, but others might be quite surprised to learn the potential severity of such seemingly insignificant actions. Either way, we all need the occasional reminder of how even brief instants of carelessness are capable of changing our lives forever. Even though the previous sequence of events happened over the course of only a second or two, before thinking clearly again and realizing I was completely safe, it is still worth bringing up for anybody that that actually reads through this build.

The problem arises when chlorinated hydrocarbons are exposed to oxygen and UV radiation or high temperatures. Even a few residual drops of chlorinated brake cleaner not fully dried off of a part can react to form Phosgene gas. While not a name heard much today, it is the chemical weapon from the trenches of WWI believed to be responsible for more deaths than any other…Not exactly something you want to be breathing in ANY quantity.

I thought I only kept non-chlorinated brake cleaner on hand, but it had been so long since using it last that I wasn’t completely certain. Thankfully I was able to quickly verify it and calm myself, since it is only the chlorinated type that has this extremely dangerous reaction. In some places, like California, I don’t think you can even get chlorinated brake cleaner anymore. Regardless, welding is a pretty intense process capable of numerous health and safety concerns. So you need to be conscious of everything you do around the welding too. Thus I can’t recommend strongly enough that it is best to ALWAYS make sure you’re using a solvent that does not have a variant capable of accidentally releasing a Schedule 3 chemical weapon in your garage. That way you’ll never even have a reason to question yourself.

Friday, October 4, 2013

While I'm cutting the second set of inboard and outboard chassis side tubes, I decided that this would be a good time to introduce a surprising 'tool' that has become invaluable to me...

That's right.  It's an every day, ordinary, and FREE paint stirring stick from your local hardware store.  This one has even been used previously for painting, so as to not be accused of any illicit procurement methods...Although with as much as we spend there, the least they can do would be to contribute a few pristine sticks to the cause.  It turns out that while the typical 4x6 horizontal bandsaw has an angle finder to help get it close and reduce the amount of time spent grinding the tube to the exact angle you wanted, it's not terribly accurate.  In an effort to reduce rework, I have been using the paint sticks primarily as follows:

First I have carefully measured and planned out my tubes on my work surface, and calculated the necessary cut angles involved.  I set the band saw as close as possible to the desired angle and cut the paint stick.

After cutting the paint stick, I can carefully lay it over the plan for the tube end being cut next, and make any adjustments necessary.  If there is a mating tube that has already been cut, I will hold their mating surfaces together and see just how close the angle naturally sits to the plan.  I only proceed once this looks to be almost perfect.

At this point, if I'm not just copying existing tubes, I should also have markings on the tube to indicate the length of either the long or short side of the angled cut, illustrated by the slightly difficult to see vertical line on the tube in the photo above.  Then all you have to do is line the appropriate corner of the paint stick up with the correct edge of the measured line, and then copy the angled edge of the paint stick on to the tube with a Sharpie.  With this line in place, and the bandsaw angle set, the tube can be cut.  Thu far this method has allowed me to cut nearly every tube to the exact desired length and angle on the first try, with no grinding required.

I'm sure that there are other ways of accomplishing the same end result, and this probably isn't even the easiest, but it has worked for me.  It also doesn't work quite as easy once we leave the 2D world and enter the 3D world, but it has already more than paid for itself in saved time, reduced effort, and improved quality.