From the October, 2011 issue of Classic Trucks / By Ron Covell
You can email your questions to Professor Hammer at covell@cruzio.com, or mail to Professor Hammer, c/o CLASSIC TRUCKS Magazine, 1733 Alton Pkwy., Irvine, CA 92606. You’ll receive a personal reply! We’ll print your name and city unless you request otherwise.

Ron Covell has made many DVDs on metalworking processes, and he offers an ongoing series of workshops across the nation covering all aspects of metalworking. Check them out online at www.covell.biz, or call for a current schedule of workshops and their free catalog of DVDs. Phone 800-747-4631, or 831-768-0705. You can send a request by mail to: Covell Creative Metalworking, 106 Airport Blvd. #105, Freedom, CA 95019.

Q. I’m working on a ’52 Ford F-1 and I want to shave the handles and install bear claw latches. After I removed the handle, I discovered there is a double thickness of metal inside the door to support the handle. If I cut a piece of metal that’s a tight fit to the hole and slowly spot-weld it in, will the extra piece of metal cause any waves in the door on a hot day after it’s painted, or should I just keep the handles in place?
Also, these doors use dovetails for alignment and I would like to keep them in place. I would appreciate your comment on these two items.
Ken
Via the Internet

A: To do the best job, I’d recommend removing the doubler inside the door that reinforces the handle. This is probably held in place with some spot-welds, so you’ll have to find the welds and drill them out. The advantage of keeping everything the same thickness is that it’s easier to get everything smooth and level with a hammer and dolly after welding the patch into place, and you can be assured that the patches will stay invisible over the long haul. I’d definitely keep the old dovetails—they help to keep the door in alignment when it’s closed.

Q. Ron, I enjoy your articles every month in Classic Trucks. I have two of your videos, TIG Welding Basics and Basic Techniques for Working with Steel. Love them both. I have a Lincoln 225 TIG welder and a very rusty ’53 Ford pickup. I am a TIG welding newbie, so I have several questions.
1. When TIG welding 18-gauge sheetmetal, what are the specific recommendations for tungsten size? (0.040, 1⁄16-inch, or 1⁄8-inch?) I’m using Lanthanated tungsten—is that the best? Cup size? (I’m using a #7.) Amperage? Flow rate? Filler rod size and type? (I’m using 1⁄16-inch ER 70 S-2.)
2. Is there a source you can recommend for small sheetmetal plugs to fill in 3⁄8-inch or ½-inch holes I’m drilling with a stepped drill bit? I researched the Whitney Punch, but can’t see spending several hundred dollars if someone sells a few hundred plugs for a few bucks.
Jerry Saumier
Grand Rapids, MI

A. I’m glad you enjoy my column and DVDs! Any of the tungsten sizes you list will work, although 1⁄8-inch is definitely larger than necessary. The advantage of the .040-inch diameter is that it has all the current carrying capacity you’ll need for 18-gauge steel, it will start the arc at a lower amperage, it’s marginally less expensive than the other sizes, and it’s the easiest to sharpen to a fine point. Ceriated or Lanthanated tungsten is best for all-around use.

The #7 cup size is fine—that’s what I use for a lot of my welding. For heavy-duty aluminum welding, I sometimes go larger, and for getting into tight places (tubing joints, as an example) I sometimes go smaller, but for general purpose work, the #7 is a good bet.

To make a puddle you’ll need at least 45 amps (the rule of thumb here is 1 amp for every .001-inch of material thickness, and 18-gauge is about .045-inch). I normally set the machine to about 30 percent more (60 amps or so), and ride the pedal at about 2⁄3 “throttle.” This gives me somewhere to go if I should need a boost of heat. The recommended gas flow is 12 to 14 cfh for steel.

The general principle for choosing filler rod size is to match the material thickness, (for sheetmetal, at least), so .045-inch rod is perfect. I welded my panels for many years with 1⁄16-inch rod, not knowing smaller sizes were available. What a difference the .045-inch rod makes! 1⁄16-inch rod leaves a bead that’s way too big!

ER 70 S-2 rod is fine. The next time you buy rod, if ER 70 S-6 is available, it’s a little better for welding on metal that may have traces of paint, filler, rust, or corrosion on it. Now, I’m sure you clean your metal very well before welding, don’t you? But even so, it’s sometimes hard to get the last traces of impurities off of surfaces, and the S-6 rod has more cleaners and deoxidizers in it.

Bob Drake sells plugs kits, www.bobdrake.com. You might also check with some local precision sheetmetal shops. I use to have them made by the hundreds, and it’s not terribly expensive. CT