Hey Mr A,

Thanks for the kind words.

Like you said, I am sharing my information in hopes that it will save someone else time, money, materials, and from frustration. My goal is to be as selfless as I can be in delivering this information.  I started this thread after I realized that the problems I was experiencing in my Bat Vehicle build and my problem solving resolutions had a good chance of being similar problems and useable resolutions that might be of some benefit to others.  vertigo     

This would fall under the heading of technique and a resource management tool.

RESOURCE FILES: In building my Tumbler one thing that has been very useful to me is my Tumbler specific resource files. I started building them during my research period and still add to them as I find additional Tumbler relevant resources. The best time to start building your Bat Vehicle Resource files is when you start your Bat Vehicle research. As you research you will find along the way embedded references to tools, fabrication supplies, books, tires, rims, axles, suspensions, bearings, specialty labor, engines, transmissions, etc., etc…… The first resource that most will find are references to the tires, not the rims, they are custom made. My resource file folders are set up under the headings of TOOLS AND FABRICATION SUPPLIES-example: welders, cutters and expendables, TIRES, RIMS, AND AXLES-example: Interco tires, SUSPENSION PARTS AND BEARINGS-example: front suspension arm bracket bearings, SPECIALTY LABORS-example steering work, CUSTOM PART MAKERS-example: custom rim makers, MACHINE SHOP SERVICES-example: lathe and mill work, ENGINES, TRANSMISSIONS, AND POWERTRAINS-example: Summit Racing and Jegs, and BODY, PAINT, AND GLASS-example: primer and weather stripping. I also keep all my operator manuals for my welders and other tools in a folder.  vertigo

A few notes on stick verses Mig welding concerning strength of welds and why for many stick is superior to Mig for most welders. I posted this on my Tumbler build but it seems that it might have some importance to new Bat Vehicle builders also.

A friend stopped by today while I was stick welding on my Tumbler and asked “which gives you a stronger weld – stick or Mig?”

“MIG will THEORETICALLY provide a stronger weld since you do not have stop/start locations or slag inclusions to worry about. However this is assuming the very best circumstances, including a welder who really knows what he is doing.  Under normal circumstances 90% of welders will make a stronger weld with stick, since stick doesn't require much skills or knowledge of the process to make a good weld. There's no gas to worry about, and just one control knob. It's not hard for even an ignorant (unaware of relevant knowledge) beginner to make a stick weld with passable weld fusion and penetration. ANYONE can figure out the correct settings for stick, through dumb-luck trial-and-error. In contrast you simply can't depend on trial and error with MIG. The problem with MIG is most MIG machines out there are both seriously underpowered (under 200 amps output.) Secondly, in my experience it's rare to find a welder that has the correct knowledge and experience to utilize the MIG process to anywhere near its true potential. The result of these two is that it is common to find MIG welds with severe, unacceptable lack-of-penetration and lack-of-fusion defects. Sadly 99 out of 100 welders never or only rarely test their MIG welds they make for strength and weld fusion. They don't realize that the most important part of a weld is in the middle where it can't be seen. To give you a specific example. A lot of welders think it's acceptable to use dirt-cheap 100% CO2 with the low-current short-circuit transfer mode, for welds on thicker steel plate over 1/8". A lot of welders also think it's OK to use one setting on their MIG machine for any and all welds.  I've run across welders who have been in the business 30 years who do this. In reality the performance of a MIG weld depends on: 1) Knowing the ideal voltage, WFS, and best shield gas for ANY given thickness of material. 2) Having a machine that can back you up with enough current. It's a poorly known fact that MIG requires 50-100% more current than stick welding. Without 1 and 2, at best you'll be welding a lot slower than you need to, at worst you'll make a weld that looks pretty, but is completely defective.”  Source: Pro Welder.

A few days ago a casual friend of mine stopped by with his dad who was visiting from out of town. So as usual we went into my shop to talk about the Tumbler. Before long his dad and I were talking about welding. Turns out his dad use to work for NASA as an engineer specialized in metallurgy. So, I took the opportunity to ask him about welding on metal parts that contained bearings. "Three rules will protect most bearings, he said." (1) Isolate your project from all grounding out sources with non-conductive supports or if using metal jack stands place non-conductive isolators under them. Also, keep your project and isolators dry. (2) Maintain the same length on your welding leads and do not use cables with cracks or compromised insulation. (3) Keep your ground lead clamp within 6-inches of the actual welding. Grind to bare metal before attaching your ground each time you move your ground. Use a heavy solid copper grounding clamp. This seemed to me like something every Bat Vehicle builder will face in constructing their build. vertigo

The second part of my discussion with the retired NASA engineer was about welding on vehicles with electronics present. “Always remember that welding circuits will search for the path of least resistance. So, keep your grounding clamp on bare metal and welding, as close together as practical. That’s why good automotive welders can get away with a lot. But if you want to be as safe as possible here’s what you do.”  (1) Do your welding in dry clothes wearing dry gloves while standing on isolators. (2) Disconnect both battery leads. (3) Disconnect ECUs and anything else with a computer chip. (4) Pull all your fuses. (5) Disconnect alternator.  “Or pull all your electronics if you are working on something that absolutely can’t fail.”

I also researched this topic on the internet and found this posting on the Miller Welder sight: “Any sane ECU manufacturer would have MOV filters and other forms of filtering the power inputs to the ECU. A lot of alternators are very noisy, along with the high voltage ignition system creating a lot of EMF and the ECU still has to run under these conditions all the time.  I work in an Electronics Engineering field (even though I am mechanical…) and I deal with ECU development and harness designs every day. The one big thing to watch out for is back feeding through components, which would be rare in this case. It doesn’t hurt to unhook an ECU because you never know if your welder is putting out enough EMF to overcome the filtering circuit on the ECU due to it being a high voltage arc onto the chassis of the car.”