Guest Anonymous Posted October 1, 2000 Share Posted October 1, 2000 Well, I have been moving slow on the project the last couple of months for various reasons but it seems to be coming together better now... Anyway, this afternoon my Dad came up and we thrashed on the subframes for a few hours. I don't know how I could do this project without my Dad involved, sometimes he seems more into it than I am and he has an engineer's mind. Sometimes this can get a little nerve racking, for example, we had the 2x3 tubing within 1/32" of an inch of being parallel to the rocker panels, this was after fiddling with it for ~45 minutes, I said "that is close enough" and he responded "no, it has to be perfect"!! So out it came again and ~15 minutes later we had it dead nuts parallel with the rocker panels. We cut out the old passenger side frame rail and replaced it with 2x3 .083 wall tubing. My Dad had one of the guys he works with make up a bunch of 4' long 90* bends out of .055 sheet metal with one side being 1" wide and the other being 1/2" wide. After tack welding the 2x3 into place and getting it level we welded the 90* bends to the floorpan and 2x3 to seal everything up. In the rear we fabricated a box out of 1/8" plate to tie the tubing into the rear subframe. We are going to fabricate a similar type box out of the 1/8" plate to tie the 2x3 solidly to the front subframe, much like Mike Kelly's set up. It turned out better than I could have ever expected!!! Well, just thought I would give you guys an update... Chris Quote Link to comment Share on other sites More sharing options...
Mikelly Posted October 1, 2000 Share Posted October 1, 2000 Hey Chris... Where the hell have you been??? Call me! Mike ------------------ "I will not be a spectator in the sport of life!" mjk Quote Link to comment Share on other sites More sharing options...
pparaska Posted October 2, 2000 Share Posted October 2, 2000 Chris, your subframe sounds great. Gonna put up some pics? I'd like to see... Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted October 2, 2000 Share Posted October 2, 2000 Mike, Seems like we keep playing phone tag...I'll give you a call tonight!! Pete, Unfortunately I did not take any pics of the passenger side from start to finish. I would guess we have it about 3/4 of the way done. I'll get some pics of it in its current stage and will do a full picture "documentation" of the driver's side. The driver's side is going to be the most difficult as there will be a great deal more hand forming of the 90* bends that tie the frame rail into the floor pan. Chris Quote Link to comment Share on other sites More sharing options...
Mikelly Posted October 4, 2000 Share Posted October 4, 2000 I saw Chris' wok on his frame last evening and he has become quite the fabricator. His work made such an impact that I got under my car last night to check a few things out.. It was already on jack stands since I was swapping my brakes out.. What I found made me want to throw up. I cannot impress the importance of trust when dealing with people in the car world. A former sponsor of mine had done the sub-frames and floor pans in my car while I was over seas defending god and country. What I found last night angered me. The guy had layed the floor pans in on the frame rail and then never welded them in... Moisture had gotten in between the frame rail and the floor pan, and my subsiquent V8 driving has caused the floor pans to tweek and twist, revealing rust and other problems within the structure. I'll be tearing this whole mess out over the winter. I am pissed... If you want it done right, do what Chris is doing... do it yourself. Welding isn't THAT hard... Mike ------------------ "I will not be a spectator in the sport of life!" mjk Quote Link to comment Share on other sites More sharing options...
Danno74Z Posted October 4, 2000 Share Posted October 4, 2000 Chris, I'm trying to visualize what you and your Dad did on the new frame rails. How did you tie the new member in to the existing structure in the front and rear areas? Can you write up a little more detailed information in this procedure. Also: 4' long 90* bends out of .055 sheet metal with one side being 1" wide and the other being 1/2" wide. Which side , the 1" or ½" did you weld to the floor? Thanks, Danno74Z Quote Link to comment Share on other sites More sharing options...
pparaska Posted October 4, 2000 Share Posted October 4, 2000 Mike, sorry to hear your rust story. I absolutely hate rust. After replacing TONS of rusty stuff on my Z, I have developed a credo: 1) Steer clear of overlapping steel joints. If the steel must overlap for strength reasons, etc., either seam weld both edges on each side of the overlap, or use a weld through primer (although in my experience these burn off) or use a very good seam sealer. My preference is to butt weld, or lap weld with a continuous seam and cut and grind back the unwelded overlap to the weld. 2) Use a rust eater (acid based) like Ospho or Eastwood's Oxysolv to eat surface rust and prep the metal with a zinc phosphate coating. 3) Paint with either an epoxy primer mixed into a sealer formulation or with a moisture cured urethane like Hirsch Automotive's Miracle Paint or POR-15's paints. Powder coating and ceramic coating are good for rust prevention also. I have been known to spray bomb parts though, but I prefer not to do that as it's not a great rust preventer. I used to use Rustoleum rust preventive paints, but the spray nozzles clog no matter what you do. Now that I've found Miracle Paint/POR-15 I try to do parts with that. 4) If I bolt two pieces of metal together, I slather antisieze or boat trailer wheel bearing grease on the parts where they touch, to keep water out. 5) If I drill a hole to mount something small like a cable clamp, etc., I use RTV to coat the hole edges. Damn, I hate rust. Ain't no way I'm going to let it come back if I can help it. [This message has been edited by pparaska (edited October 04, 2000).] Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted October 4, 2000 Share Posted October 4, 2000 Danno, The 90* bends were made to help attach the sheet metal floor pans to the 2X3 tubing. The 1" side is welded to the floor pan with the 1/2" side running up the side of the 2X3. The bottom of the 2X3 is at the same height as the factory frame rail so ground clearance should not be an issue. Of course part of the 2X3 now protrudes into the interior of the vehicle. I agree with Pete as far as overlapping, but my fabrication and welding skills are not good enough to butt weld two different thicknesses of sheet metal. I took the easy way out and overlapped the 90* ~3/4" on the existing floorpans then seam welded it the entire length, on both the 2X3 and floopan. Once the subframes are completed and the cage is in the car I plan on sandblasting the entire underside and interior then spraying all of the sandblasted areas with Por 15. Attaching the 2X3 to the existing frame rails was the part that I was worried about. In the front I cut the frame rail right were it begins to bend, or become straight under the car, ~1 1/2 to 2" ahead of were the floor pan turns up into the firewall. The 2x3 was then tack welded to the existing frame rail in the front. 1/8" steel plates will then be fabricated to cover the side of the 2X3 running 6" down the 2X3 and 8" up the side of the existing frame rail. A "top" plate will then be fabricted that will follow the contour of the existing frame rail and 2X3. This will create a 1/8" thick plate "box". All will, of course, be seam welded. In the rear we did pretty much the same thing as described above, basically creating a 1/8" plate channel with the bottom following the contour of the floor pan. I know this is all difficult to understand, hell, I am the one doing it and I am getting confused!!! Once we have some pics and I am able to post them it will be a better display of how it was done. We should be working on completing the passenger side and driver's side of the car this weekend. Mike Kelly is going to come over with his digital camera and snap some pics. Once it is all completed I'll do a more complete writeup. Chris Quote Link to comment Share on other sites More sharing options...
pparaska Posted October 4, 2000 Share Posted October 4, 2000 Hey, Chris, I did what you're not supposed to do - learn to weld on your project car! Butt welding 18 gage new floor material to the existing 22 gage tunnel bottom was LOTS of fun. Weld an inch, burn througout, let cool, weld to fill hole, grind, etc. Sometimes I could go 6 inches (not all at once) and not burn through. The stuff doesn't look pretty, but its strong, and the heat didn't warp anythng. I never would have thought that the sheetmetal on the Z was so thin. Talk about paper! [This message has been edited by pparaska (edited October 04, 2000).] Quote Link to comment Share on other sites More sharing options...
Danno74Z Posted October 4, 2000 Share Posted October 4, 2000 Chris, Thanks for the detailed explanation on your frame rail work. As John Belushi said in "The Blues Brothers" movie, I have seen the light. Can't wait to see some pics. when you post them! I will be in VA (Oakton area) at the end of this month to visit my sister and her family. At the same time, Mike and I are planning to try and get together (got to see his machine). Perhaps, you can join use if you have the time. Dan Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted October 5, 2000 Share Posted October 5, 2000 Dan, Sounds great!!! I look forward to it, just keep me posted with dates, times, etc... Pete, I tried to butt weld the sheet metal when I did the battery box repair. After just one evening of it I realized it was beyond my skills!!! A friend of my Dad builds race cars and was telling me that when he welds different thicknesses of sheet metal together he keeps the heat on the thick metal and draws the "bubble" over onto the thinner metal and just keeps going back and forth an inch or two at a time, ALOT easier said than done!!! The way I choose to do it really kind of makes it idiot proof, which is exactly what I need. Chris Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted October 5, 2000 Share Posted October 5, 2000 What are you guys welding with? Stick? I welded light gauge steel (down to 22 ga.) for about 12yrs before I figured out I could make more money in computers and middle management (whoo hooo, my lifetime goal, middle management). At any rate, Tig or Mig is the only way to go for things that light. I used mig only and found after a number of years you have the control to get on and off the trigger and lay a series of pools overlapping each other without burning through. (Don't get me wrong I still burned through from time to time, but less often in later years). A good thing to have in your welding arsenal if you do blow through, is a hunk of copper or brass. Pull it on the backside of the hole and click the trigger a few times in the hole to fill. Works like a charm. This is for light gauge materials (steel, if its aluminum, find yourself someone who can tig, it does'nt work well with a mig torch and argon). Stick is for welding heavy iron, gas can be used but the heat makes warpage a problem. Oh well, thats my nickels worth... Lone Quote Link to comment Share on other sites More sharing options...
Mikelly Posted October 5, 2000 Share Posted October 5, 2000 Chris has a nice Mig unit. I also have one at my brothers house, but need to get a larger circuit breaker wired into my garage before I bring it back to my place to weld anything. I'm gonna be buying my own unit over time, but we'll see. I'm currently looking for business partners to open a performance based shop in Fredericksburg, possibly with a Dyno installed... we'll see, but for right now I'm just gonna beg and borrow what I need to resolve my floorpan issue. They car won't see any serious use until I get the rust and damaged pans out of the chassis of mine, which will include removal of the interior and possibly the motor and transmission. Mike ------------------ "I will not be a spectator in the sport of life!" mjk Quote Link to comment Share on other sites More sharing options...
pparaska Posted October 5, 2000 Share Posted October 5, 2000 Chris, yes, pool on the thick, go over to the thin, an inch or too at a time. That's what I found to work also. Lone, I'm using a cheap little Dayona Mini Mig with lots of hours on it. I have only experience welding on the car - I know stupid, but that's what I did. I got decen pretty quick though, since Mig is pretty easy to self teach. I really want a nice Tig/Mig setup. I don't know how to fund a $1500 piece of equipment for hobby use though . I'd LOVE to be able to TIG aluminum stuff, and Stainless. Quote Link to comment Share on other sites More sharing options...
jeromio Posted October 5, 2000 Share Posted October 5, 2000 Another technique that has worked well for me - esp. with thin to thick unions, is to lap joint the metal - maybe 3/8 to 1/2. Then set the welder fairly hot and weld on the thin lapped side, in the middle(-ish) area of the lap. It will burn thru the thin but not all the way thru because the other metal is on underneath (or on top if you're under the car). Then, as you move along the seem, you zig zag and melt that exposed top lap of metal. If you're really concerned about the rust, you can either grind off the underside lap or "seal" it with a weld on a low heat setting (much less chance of burn thru). It really is amazing how thin the sheet is on these cars - and no zinc or anything! I've replaced all the rusted out bits with 14ga. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted October 5, 2000 Share Posted October 5, 2000 Lone, Like Mike said, I have a nice Mig setup. I got an unbelievable deal on it, which is the only way I was able to afford to get the unit. I got the unit (Lincoln SP125), 80 cubic ft bottle and a Jackson autodark helmet for, if I recall correctly, $550.00. A friend of my Dad (the one who builds race cars) knew the owner of a welding shop in Richmond, VA. I, like Pete, basically learned to weld on this project as it had been over 15 years since I had done any welding and that was all stick welding on heavy guage materials. By the way, great idea with the brass or copper!! Michael, You know you are more than welcome to my welder anytime!! We can transport it to your house or you can bring anything over that needs to be done!!! Jeromio, What you described is sort of how I did my battery box repair. I cut ~1" wide pieces of sheet metal and welded them to the firewall and fenderwell outlining the entire "hole" with ~1/2" protruding into the "hole". I then handformed the sheet metal replacement panels so they would lie flat on the protruding pieces of metal. The replacement panels would then lie flush with the existing firewall and fenderwell. From inside the engine bay it appears that everything was butt welded into place. I then seam welded all of the 1" pieces of metal and ground all of the welds flush. Using this method I was able to prevent any burn through and it made fabricating the replacement panels much easier as I would just weld fill any gaps with weld. Chris Quote Link to comment Share on other sites More sharing options...
pparaska Posted October 5, 2000 Share Posted October 5, 2000 Copper "spoon". Yeah, I made one one day out of a piece of copper pipe cut and flattened and a small pair of vise grips to hold it. It works great for filling holes. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted October 5, 2000 Share Posted October 5, 2000 Cool, glad to hear you guys are using mig, its sooo much easier. Thin gauge metal is difficult as we've discussed to weld. There just isn't the thickness to sustain a pool of metal without it caving in unless your careful and keep your pool realitivily small. As most of you know as well, welding small sections and skipping around minimizes warpage. I hear ya Pete on the Tig, I'm in the process of self teaching myself to be a bit of a panel beater using aluminum. (to see someone who is REALLY good at it, try www.tinmantech.com Kent White is probably one of the best I've seen. I've seen his work firsthand in the long since sold Harrahs auto collection and the man is phenominal). I'd LOVE to be able to swing a TIG setup, they're a little tricky to use, but if you've gas welded before you can catch on pretty quickly. The welds as you know are absolutely gorgeous. The guy I mentioned above Kent, does aluminum welding with GAS using a really small torch, and teaches it matter of fact, it too looks good but requires flux and much more skill. For metal fabrication, one book that is a must have is Metal Fabricators Handbook by Ron Fournier (http://www.fournierenterprises.com). It shows all the proper ways of fabrication and this cat is extremely good at it. It goes into all facets (including building custom headers and rollcages/rollbars) and really is worth having. The dude has built indy cars, and his own rod bodies out of aluminum using wooden buck templates to check the work against. Oh well, I've rambled on again, but I felt these guys deserved mentioning when it comes to metal fabrication. Regards, Lone Quote Link to comment Share on other sites More sharing options...
Danno74Z Posted October 7, 2000 Share Posted October 7, 2000 Guys, I found this site for welding equipment awhile ago. I have talked to them and they are very good and the prices are excellent on name brand machines. They also have free shipping. http://www.welders-direct.com/ Quote Link to comment Share on other sites More sharing options...
Drax240z Posted October 7, 2000 Share Posted October 7, 2000 A little more info about TIG. I had a unique work experience, in that part of my duties at my last job included welding... even though I am not ticketed. I welded every single day in the 16 months I worked for the company, sometimes for minutes a day, sometimes for 6 or 8 hours a day. I TIG welded for about 12 months of this time... Maybe I am a slow learner, but I picked up stick and MIG quickly enough, but it took me quite a while to get good at TIG. (By good I mean that I would be willing to weld $5000 of Titanium together) My partner in crime there had been TIG welding for 3.5 years to achieve bicycle frame quality welds... (PERFECT) I'd love a TIG, and I don't want to talk anyone out of it, because honestly its one of the greatest pieces of equipment I've ever used. (A lincoln squarewave 255 IIRC) But be forwarned that its not something that you will necessarily pick up in an afternoon or as you use it, like MIG... I was TIG welding scrap stainless steel for about a month before I'd move on to any of the heat exchangers or other big money items we were building. ------------------ "THE STREETS WILL FLOW WITH THE OIL OF THE NON-BELIEVERS" Drax240z 1972 240z - L28TURBO transplant on the way! http://members.xoom.com/r_lewis/datsun.html Quote Link to comment Share on other sites More sharing options...
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