Floorpan replacement

Date 11-03-2006 04:04

Hey RangerMan,
I recently did a restoration project for a customer on an original '68 Mustang Cobra 427GT. We replaced both driver and passenger floorpans including the forward kick-pads and seat pedestals, modified the tunnel for a new transmission with floor shifter, the entire trunk pan and fender well repairs, the forward frame plates, and the driver's side front wheel frame brace. I had 50 hours of actual fabrication and welding that was done with 5 trips to his home for 10 hr. days. My fee was $45 mobile fee to his home each session, and since I work on a cash-only basis, $25/hr for the 50 hrs. Total= $1475. He was very satisfied and he has recommended me to all his friends and has gotten me some serious work. So, as you see, my rate may seem low, but here in SW PA it is good money and his referrals have been extremely fruitful.

If you can weld, I would certainly suggest do it yourself. To replace a floorpan, you need to cut out the old, fit the replacement pan, grind welded seams to bare metal and weld. The replacement pan will have to be cut, bent, and fitted properly to have a good, sound job. Also, you will have to weld the seat pedestal to the floorpan. Since car metal is quite thin, 22ga, you don't need a lot of power to weld this metal. I used my Miller Sidekick 90Amp for all the thin panels, and my Miller 172Amp for the frame welds. I took a couple of pieces of scrap cutoffs to set up the 90A, and surprisingly I only had to weld at 75A and the welds came out great. I used .023 ER70S-6 wire and C25 gas. You need the thin wire for this body metal so as not to burn-thru. I don't use flux-core wire. Also, be very careful when welding as any undercoating and adjacent interior material, if left in, will catch fire. As I welded, Dave was underneath the car with a wet towel just in case. The saving grace was that he had the entire interior stripped bare and the dash covered with a welding cloth. The battery cables have to be completely disconnected and he had removed the gas tank for the trunk panel replacement.

I couldn't guess at how many hours you would have since I don't know how adept you are metalwork and fabrication, and what equipment you have access to. I will say that you can save a considerable amount doing it yourself. I must say it was an honor to work on this car as it is one of only five of the originals left in existence. He had an offer from a collector in England who offered him $250,000 for it. I'll try to get some photos and post them here.

Hope I gave you some insight and feel free to ask any questions.......Denny

By RangerMan Date 11-03-2006 13:19

Denny,

Thank you! That was exactly what I was looking for. That is a piece of history that you got to work on. Thank you for the details as well they will come in very handy!

My skills at the moment are non-existent, but I am ready to learn. I am still looking for a car, but the majority of them WILL have rusted out floorpans, trunks, etc. since they didn't use any sort of galvanized steel. I'm looking to do a resto-mod on a plain Jane 65-66 coupe (basically something with no historic value). I'll be taking welding classes as well before I start on the floors...my wife's (the teacher) one condition on buying the welder - must take classes.

Even at your rate (which you admit is a bit low) that is the cost of a welder (looking at the Lincoln 175 since I have 220V in my garage), materials (gas, repro floor pans, wire, etc.) and any other tools I might need. If it took you 50 it will probably take me 80, but time isn't so much an issue as I can do one panel at a time over the course of a month. My goal is to do 99% of the work myself (for the entire resto-mod) to save money for a paint job since setting up a paint booth in a very small garage isn't going to work very well.

Thanks,
Chris

By yorkiepap (***)

Date 11-04-2006 02:07

Hey Chris,
You're quite welcome. This was the first car in all my years of welding I had the opportunity to do virtually a "frame-up" restoration. And to get an initiation with a classic like this....LOVED IT!!!! The first day I arrived and walked into his garage, I guess my jaw dropped. This car is magnificent....and I'm not a Ford guy. I do love the classics though, no matter what make, especially the '60's-70's muscle cars. Now, those were cars.....each had their own design look that made them so individual. Not like today's Euro trash look.

The owner, Dave, really took his time and did most of the "grunt" work with cutting, fitting, and all the finish grinding and painting of the new metal. I told him I would only do first class work and no half-a$$ mediocre crap, since my side "hobby" is important and I want new customers and good recommendations. He agreed and said he would accomodate anything I needed to do to make it first class. We had a lot of fun and, even after 40 years of welding, I still managed to learn new techniques. I will say this was the first time I ever welded flat on my back for hours at a time.

OK...FOOD FOR THOUGHT:

I will offer you some suggestions so you can start doing some prep.

1. Definitely go to school and really learn all you can.
2. Practice...practice...practice!!
3. Get the "feel" of your welder by welding same thicknesses, and different thicknesses together. You will see how metal will bond and bind correctly when you learn technique: heat settings, wire speed, gas flow, and travel speed. Practice...practice...practice.
4. Prior to starting, set up your equipment for the metal you will weld by using scrap pieces the same thickness. Scrap the scrap first....not your panels. Get the "feel" of the metal.
5. TAKE YOUR TIME!!!! Do not rush any process. If your eyes start to tire, or things start to look blurry...STOP!!!!! Let your visual system get accustomed to welding gradually.
6. SAFETY!!!!! Protective clothing, good leather gloves, steel-toe boots, safety glasses. I must say I prefer the auto-darkening helmets.
7. TOOLS: 4" angle grinder a must....can use both 4" grinding wheels and cutoff discs; 6" & 11" vise-grip welding clamps; 2" thru 6" C-Clamps; Arrow welding magnets...25 & 50lb; needlenose pliers with cutter, wire brushes, 12-15" Crescent wrench which you can use to make some nice small bends on the metal for tight spaces or corners. You can get most of these items reasonably on E-Bay or Harbor Freight to save a few bucks.

Chris, you will find you will enjoy a project like this immensely and look forward to each day's progress. Remember, quality work is paramount.....think about someone else doing your restoration job and would their work satisfy you? OK....you keep in touch and don't hesitate any questions.....there are no dumb questions...sometimes dumb answers though.......Denny

By Sourdough (****)

Date 11-04-2006 04:26 Edited 11-04-2006 04:29

Anybody skilled in replacing the rocker panels in a 69 chevy truck? How 'bout a 76? Will be a couple seconds, till I'm back on line! Changing servers. . . . .

By jwright650 (*****)

Date 11-04-2006 12:41

If you have access to the back of any of these panels, you can use a strip of 3/8" thick copper or brass to fill in any holes or to help with any spots where you burned through(copper or brass will not stick). A heavy piece of steel or aluminum placed tightly against the back of these joints will also help act as a heat sink to keep you from blowing holes through that thin material. Using a push angle rather than a drag angle will also help with welding thinner materials. Keep in mind that you will need to watch your heat input to keep from warping your panels. Weld small nuggets at first and skip around not placing any welds too close together until they have completely cooled. A wet (soaked) rag on the backside of the joints immediately after welding will help quench the sheet metal and help with the heat soaking in too far away from your welds.