Welding hateful metal.

[MusPuppis]

Ok, so the metal isnt hateful, its just malicious.

Heres the setup -

Ive been practicing with bits of my Z that I cut out (its sad I've cut so much out its provided a steady stream of practice media..) trying to mate them to little bits of 18 guage sheet. Soon, at the end of this month most likely, I'll be fabbing and welding in my subframes and rebuilding my floor. I've decided to use 18g for the pans (any advice on that would be appreciated as well.. too thick? not thick enough?). I'm having serious trouble mating the 18g to the Z's stock metal.

The Z metal is very thin, but more so than just thin (ive welded thin metal like that before..) its.. I dunno.. Cheap? I'm having trouble getting my arc started at all. As soon as I hit the trigger (im starting the arc on the new 18g) and drag it over to the seam it pops through the cheap metal in about half a second. I'm not even able to form a puddle.. Just *poof* burn through.

I'm starting to get seriously worried that I cant do this with my welder. I have a Lincoln 100amp mig dealie running Flux Core. I know Flux is supposed to be a little hotter than gas and less than optimal for thin sheet metals. In my situation (going with a gas welder or upgrading my welder to gas are not an option.) what would you all do?

I have the welder set to the lowest settings I can. Wirespeed is 1, tapped voltage is "a", lol.

I expect welding large peices will be a little bit easier as the heat will disperse better, but I'm trying to arm myself with as much knowledge on this as I can. When I get my steel I will of course practice more on large peices.. BUt I'm curious what the experts think.

Below is a pic if what I have planned. A quick, crappy mock-up in Photoshop. The red bars show how I will be building the subframe connectors. They actually extend a ways under the car of course, but I just wanted to show the section dealing with the pans so you all can see how they will be divided. The vertical bar is of course the subframe. The horizontal bar is a stiffening component that doubles as a mount for seat brackets I'll be fabbing up. Its slightly out of its actual place in the pic. Now, the bars will actually extend above the floor some. About an inch will the below and an inch above. It'll make a little mound thing in my carpet, but this allows it to butt up against the hatch rise as well as the rear subframe for added stability. This also effectively sections the pans into 4 sections. Which for me, I see as a plus. If I screw up I only ruin a small peice of steel instead of a massive peice the size of the entire pan area.

Given the fact that the pans will have to support weight, I'm thinking that making about a hundred million tack welds wouldnt be an option?

Anyway, any adivce, comments or info on the method I should use and/or the design would be appreciated.

[Fishy Jim]

Adding connectors that run parallel to the chassis will not add lateral stiffness. You should consider making X's across both sides instead and have them meet where your seat bracket is (I'm assuming that's what the horizontal bar represents). You have a front and rear attachment point for the seat rails too (if you're still using them, which I'd recommend, even on a racing bucket - so your girlfriend can drive you home when you got wasted). So rather than placing that cross member in a location ideal for the seat, you should put it somewhere where it can tie into something solid on both sides and actually help your chassis. You can put some 1/8" flat stock across the pan to mount the seat to. Racing reg's typically give a minimum backing plate dimension for seat, belts, and cage mounting points anyways - follow those.

[MusPuppis]

I'll be using the seat rails. The rear mounting bracket location for the seats will be directly to the floor pan itself, ala-stock.

That horizontal bar butts up against the transmission crossmember, which continues along the top of the tranny tunnel to the other side (and of course the actual crossmember itself which goes straight across). So, in effect that horizontal bar uses the tranny crossmember as a "bridge" over to the driver side (rhd car) bar. its not nearly as effective as going straight across of course. The horizontal bar itself is a brace first and a seat mount second. Butting against the tranny crossmember just happens to be exactly where the old seat mount was located, lol.

The other rails are just improvised versions of the stock rails.. which were paper thin, narrow and didnt connect in to the rear subframe at all. They (literally) sprung up near the rear of the pan and continued on into the engine bay section of the frame, being welded to the bottom of the front frame rails and butting against the front suspension.

I wouldnt be able to really make X's in the pan area. The design of the Z makes suitable mounting locations few and far between. Someone more skilled than myself could certainly do it, but I suck.. so that effects my project decisions.

[hankj]

Mus,

It's time to bite the bulett and buy the gas kit for the macine, if one is available. If not, it's time for a new machine! Flux-core and thin sheet don't much care for each other. You'll be lucky to even make tacks with it. The ideal setup is TIG, then solid wire with pulsed MIG, but that = $$$$ either way. Something like a Hobart Handler 140 with .023 and C-25 will do the trick with practice.

Hank

[kinelbor]

I managed to weld thin stuff with my Lincoln 100, by doing a really wide sweep (1/2") and moving it quickly back and forth. I am VERY new to welding so this is probably the worst way to do it, but it didnt burn though. It was on a bike frame and it would burn through on lowest heat if I didnt do it that way. Its really strong so I guess it worked.

[mikeatrpi]

Mus, you can go here and see what I did on my ZX. Click Rockers, Floor and Subframe galleries specifically. I patched my floors, body and subframe with 18ga using a Lincoln sp-100t MIG with 025 and C25. For the subframe I made two "sides" and a "bottom"... I made the bottom snug so I had to tap it on with a hammer before welding.

Anyway- I used a flap wheel to make sure the metals were clean at the joint, and I screwed the patches down with sheet metal screws wherever I couldn't fit a clamp. I had problems like you until I kept practicing. I used A-2.5 for my best results with body metal. B-3 was perfect for 18ga.

[MusPuppis]

**** **** ****.

This creates a serious problem for me then. I start college soon and a new welder is absolutely out of the question. I can barely afford the sandpaper I need to keep working on the car. Setting this one up for gas is equally impossible (100$ or so for the kit + 150+ for the bottles + money to fill them).

This puts a serious kink in my plans unless my some miraculous stroke of luck I come up with a huge (huge for me) sum of money out of the blue that isnt eaten by rent, tuition or the ever present need to feed myself.

Atleast I can weld in the rails for now.. Thicker metal all around should allow me to weld that atleast.

[James D. Clark]

I recommend the gas and .025 dia. solid wire if at all possible. Also, get some copper sheet or you can take copper water pipe and flatten it and shape it to fit as a backup to absorb the heat at the weld seam to keep from blowing through. You will have to find a way to hold the copper against the back side of the weld. Good place to have a helper or use temporary rivets. Use a lot of tack and short bead welds spaced out and let cool before closing between tacks.

[Fishy Jim]

Your welder doesn't have a solenoid built into it? You can piece together the rest off ebay or at your weld shops. See if they have a returned one or a demo. The hose and fittings are cheap (regular air hose will work fine). The bottle doesn't need to be all that big. Gas + solid wired is cheaper than buying flux wire.

Solenoids aren't that expensive either. Maybe $30.

My 80cf tank was $120 filled with C25 (but that's because my supplier kicks butt). It was also a few years back, and they might have gone up.

You could always donate (sell) plasma. That's $200 a month right there. lol I had to bleed to finish a couple of my classes too. Nothing like the hit in the shorts of a $375 physics book.

[MusPuppis]

Nope, no selonoid.

I'll see what I can manage, but it really doesnt look promising for quite a while. Guess I'll have to just weld in my rails when I get the steel and not worry about the floors until I can afford to do it right.

I wonder what a welding shop would charge to weld them in for me.. Assuming I cut them to fit and make sure all they have to do is actually weld them in. That leaves a bad taste in my mouth though.. Half the point of this car is to do it all myself.

Oh well, as always time will tell.

[Fishy Jim]

You could also rent another welder and tank.

The MM130XP was $25/day and they gave me a sample roll of wire. That was also a long long time ago. I ended up buying mine the next year.

The solenoids miller uses are 90psi rated, 24vDC gas solenoids (normally closed). You should be able to source something that will work without too much trouble. You also probably don't need one rated over 50 (safety margin). I had mine out of my hobart tig machine because the bozo who had it before me broke the inlet fitting. I just used a car battery charger to test it after JB Welding an adaptor into the inlet, so 12vDC might be what they're running them at.

They have some 12V ones at my surplus place, but I'd check the trigger voltage of your machine before getting one (I'll pick one up and send it to you for cost if you want). I need to head back down there later this morning anyway, so I'll double check what they are. I think they were marked 5 or 10 bucks.

[BusDriver]

Dude, to be honest, if you are THAT strapped for cash, then cover the car up in a safe place till you can afford to do it right. If you can't afford this, how can you prime, paint, repair, and make this car safe?

Better to wait and do it right than to hack it now.

Save up for the parts and tools you need and then proceed foreward, rinse, and repeat.

Concentrate on college, get a good job going, and you will be able to really tear into this thing.

[MusPuppis]

Well,

I have all the tools I need for this project with the exception of a welder capable of doing this sheet metal. I also have a budget laid out that takes care of everything the shell needs EXCEPT when things like this creep up. Of course I know in any project there are unexpected costs. But I have money alloted for my steel, consumables (sandpaper, wire wheels, body filler, etc) primer (it wont be getting painted for some time.. so for now, its PPG DP90LF) and assorted other odds and ends to wrap up the shell. Its just that I pretty much have exactly enough to do that and not a dime more - heh.

Also, as to doing it right and safe.. I will never EVER cut corners that will make the car dangerous. I also wont cut corners that will comprimise the finished product's quality. I'm not building a show-car so I dont have to be completely **** about every single detail, but when the shell is done it will be straight, smooth, rust free, stronger and safer than when it was brand new.

My goal is to complete this shell before January so I CAN put a tarp on it and slow down. The shell is in such bad shape if I dont take care of the problems now, in a year or two when college is done and another year or two once Im settled I dont know that the car will be salvagable. All the mechanical aspects of this build will be a slow and bit by bit process, buying what I can, when I can to slowly rebuild the car but getting the shell done is a high priority. My situation as far as storage isnt ideal either. The garage that will house the car is a one car setup that barely fits one car. When I had my truck in there you literally had to turn sideways to walk around the sides of the truck.. So re-assembling the car (not totally.. body stuff. Hood/Fenders/Hatch/Doors etc) is part of the storage agreement. My Mom has graciously volunteered the space free of charge, but I have to keep the amount of space I take up to a minimum.

In the end, if I cant do it right, I'll work something out to hold the whole thing off until I can do it right.. But I'll exhuast all my other options before-hand, hehe.

I'm gonna call around and see what the cost would be to just rent a gas welder for a day or two.

[professur]

If it's not carrying any weight, you could just pop rivit it. Alternatively, you can drill small holes in the top sheet and just do quick tacks at close intervals. I've yet to see a car with the seams more than spot welded every two to three inches.

Are you flanging your replacement pans, or just laying it over the top?

[Fishy Jim]

I happened to find an open box for the gas kit hobart sells. The solenoid was 115v and also rated for 90psi continuous use. That kit was only 80 bucks and it came with 2# of wire along with the regulator and hose. For that price, piecing one together isn't really saving you all that much.

They also had 20# bottles for $79 It wasn't at my welding supplier, so who knows if you could do better on the kit. I know darn well you can do better on the bottle.