Electric Tape Hacks For Working On Cars

There's a big difference between knowing what needs to be repaired and figuring out how to repair it with what you have on hand, ie, hacking it. For example, I needed to clamp up an angle brace inside a subframe member so I could drill holes, but the "C" clamps I got from Harbor Freight weren't very "C" like. In fact, with the top of the clamp throat being basically in line with the top of the clamp, it appeared to be useless for clamping anything but two flat surfaces together. I needed to get the top of the clamp down inside the subframe, so I used some electric tape and a socket to hack a clamp extender.



Electric tape is ideal for such hacks because it's strong and hold tight if you stretch it, but also comes off very easily unless you bake it on or age it in the sun. Another electrical tape hack is winding it onto your finger in reverse to hold a nut. In this case, I was reuse the same tape from the clamp, making it a frugal hack. The shaky finger is just how us old guys get when we've been exerting ourselves for a while:-)



Some of my proudest moments as a teenager working on cars were getting at nuts and bolts friends couldn't deal with, one of the few advantages of having small hands. But sometimes, you can't get your hand into in to the end of a bolt to hold a nut, not even two fingers. So the best you can hope for before reverting to taping the nut to a stick or into a wrench is sticking it to a reverse tape job on your middle finger. The great advantage of using a finger is feel, since you can rarely see into locations that you can't reach.

Drilling Steel For Sheet Metal Screws

When using regular sheet metal screws, as opposed to the self tapping kind, you have to pre-drill the correct size hole. For the #14 sheet metal screws I'm using to hold the new subframe elements in place on the unibody until I bolt or weld, that turned out to be a 3/16" bit. The hole needs to be just big enough to fit the shaft of the screw, or else you'll break the head off when it gets to the point where the hole is too small. That's what happened here:



When you're sliding a new piece of metal up inside an existing subframe rail, and you don't have any way to clamp it or force it against the surface it will be contacting, you need to pre-drill the hole before you put the piece in the unibody. Otherwise, the drill would just push it back from the hole:

Run Time = 23 seconds



I found this nice little chart for the smaller sheet metal screw size pilot holes after the fact. This other site heavily quotes the I.F.I Fastener Book. While there, I learned that there's a "right" side to a stamped flat washer, something I never knew. The side with the chamfered edges (smooth rounding) faces out to the bolt head or nut. Interesting.

Buying Steel Tube For Car Frame Repair (Unibody)

Bought steel for the first time in my life this morning. I went to the local steel supply company (they do retail as well as commercial) to get some steel tubing to try to replace unibody elements with my own frame, and I also intended to buy some 18 gauge cold rolled steel sheet for the floor repair. It turned out they didn't have any 18 gauge scrap, wthat means I'll have to buy a 4'x 8' sheet if I get it from them, which costs about $68, and weighs 2 lb per square foot, or 64 pounds a sheet. I didn't want kill somebody having it fly off my roof rack and I didn't want to fold it in half, so I'll have to come back with a pickup truck if I buy the sheet steel from them.

They did have some light wall steel tube in stock, so I bought two 6' lengths of 2"x3" rectangular tube, with a 0.083" wall thickness, or 1/12". The weight on the tube is 2.73 lb per linear foot, the next thickness up being 1/8" (0.125") which weighs 3.85 lb per foot. I'd set out intending to buy 16 gauge, which happens to work out to a 1/16" (that's happenstance, not a U.S. steel gauge translation), but they didn't have tubing that thin. I'd done a little Internet research which suggested that 16 gauge was common for unibody frame elements, but I'm happy with the steel tube I bought.



Doing the research, I noticed that new car manufacturers have switched to metric for sheet steel measurements, and I saw number ranging from 1.0 mm to 2.0 mm in discussions about frame construction. 1.0 mm is a little under 0.04 or 1/25", meaning 2.0 mm is right around the 1/12" that I ended up buying. While steel is priced by weight, the United States Steel Gauge is given in fractions of inches (or translated to mm). I'll just give the ones that work out nicely to inch fractions:

1/8" = 11 gauge = 3.18 mm
1/16" = 16 gauge = 1.59 mm
1/20" = 18 gauge = 0.953 mm

All I need now is one of these steel cutting machines:-)

Run Time 2:17



The problem with buying steel tubing rather than steel channel is that I'll gave to do more cutting, and all I have to do it with is a 4-1/2" grinder with cutting wheels. I don't know how accurate I'll be, but I have enough extra stock to practice a little. My goal is to leave the tube whole (four walls) wherever possible, but to cut and peel back the ends for flaps to attach to the existing body steel where possible. Should be interesting when I get out to my garage/studio tomorrow and start measuring.

Buying a Harbor Freight Flux Cored Welder

My next trip to Harbor Freight I'm going to pick up their 90 Amp Flux Cored Welder (ITEM 44567) which lists for $149 but is on sale at the stores for $119.99 plus 15% off by coupon. It only weight 34.5 lbs, which helps explain the 10% duty cycle at 80 Amps and the 18% duty cycle at 60 Amps. Uses .030" flux cored wire, comes with a starter spool. But the two really neat things about it are that it's so cheap, I may as well use it for a website learning tool, and that it runs on 110V, in case it happens to last beyond the period of time for which I've rented a garage/studio.

I had planned on buying a Harbor Freight MIG welder, a couple of friends have used them over the years, but they are fairly notorious for wire feed problems. I assume the Flux Cored welder will have the same problem with the feed, and I've read online that they suffer from a design flaw that leaves them with a hot tip. A "hot tip" is slang for a tip that's always on when the welder is powered on, meaning if you lay it down and it touches ground, it arcs out.

I wasn't sure about the whole flux cored technology since I never heard of it before looking at welders in Harbor Freight last week, but I found a nice write-up on weldingengineer.com that lists a number of strong points, my favorite of which was "Low operator skill required." Also found a demo from a guy welding up an exhaust pipe who looked pretty indifferent to protective clothing:

Run time: 3:16



One of the problems with inert gas welding, which is that a breeze can really mess you up. With flux core welding, the flux inside the core generates the inert gas when it's heated up, which protects the arc. I figure that after a little practicing, I'll start with the floor pan repair and then get to the unibody. Besides, the new floor pan will give me something to weld the unibody to!

Harbor Freight allows anybody to download the manual as a PDF file. The warning to make sure you are ready to work before turning the welder on "to avoid unintentional welding" certainly sounds like a hot tip to me. The 18% duty cycle amounts to 8 minutes and 12 seconds off after 1 minute 48 seconds on. I thought they meant welding time, but it looks like they mean "welder on" time, which strikes me as odd - how stressed can the welder be if it's not creating an arc?

Did My Improper Great Stuff Foam Use Cause Frame Rust?

A 22 year old economy car in New England is going to have a lot of rust on it, unless it lived in a garage and was driven by a little old lady who avoided snow (and road salt). So five or six years ago, when a friend of mine mentioned that four wheel drive off-roaders filled their frames with Great Stuff foam to combat rust and corrosion, I figured I'd give it a shot. After all, there were plenty of little holes rusted in my unibody subframe already that I could stick the applicator straw through and fill.

Well, filling up with foam seemed like a smart idea at the time, but when I took the car off the road this week to start a rehab project for the ifitjams website, I realized that in most places the Great Stuff was doing great and the steel was doing poorly. In fact, the steel was so corroded that the if it wasn't anchored in the Great Stuff, I think a lot of it would have fallen off the car a long time ago. Maybe filling the frame with foam makes sense when it's pristine from the factory, but here's what I found digging all the Great Stuff out (and it did hold up great!)



I'll admit I never read the can, they might have warned dummies like me about foaming a unibody that had already started rotting away. What I found pulling the foam out was that it was often damp, despite the fact that the car had been sitting in a garage for the last month. Whatever water got in or moisture that condensed on the steel out of the air appears to have persisted because the foam (closed cell, I believe) kept the air away from it. Keep steel damp, mix in some oxygen, and you get rust, rust, rust.



None of this is intended as a knock on Great Stuff, it does a terrific job for insulating houses and filling all sorts of spaces, but I'd think twice about shooting your car frame full of it. After the fact, it occurred to me that those off roaders may have filled up with foam for flotation reasons when they hit the water, not to prevent corrosion. Those trucks have real frames, and the drivers usually beat the mechanicals to death long before any frame rust can have a serious impact.