New Chassis Jig - Your thoughts/advice please

admin

I would like to build a chassis jig for my garage, to build a new tube chassis drag race car or two, here are my requirements:1.  16 feet long, 4 feet wide2.  3 legs on each side of the jig3.  Legs must be removable so I can store the jig when not used easily4.  Prefer to bolt together as much as possible (minimal welding)5.  Used for new construction only, not pulling something bent back in to shapeI've done some research (on the web, talking to people), and here's some of my findings:1.  Some guys use 6X6X.250 I-Beam, either bolted together, or welded, or both2.  Some guys use 4X4X.250 Box tubing, welded only, not boltedI like the 6X6X.250 I-Beam option, all bolted together, I could have the pieces cut when I buy, then drill holes to bolt together myself, using some leveling mechanism in the legs (welded nuts, with bolts I can use to adjust height at each leg).I think the 4X4X.250 Box tubing option would require a lot of welding, and I assume the welding could/would warp the jig to a degree (not sure how much).Someone told me that the I-Beam might be twisted when I buy it (or might twist or sag when I try to use it), which could cause problems leveling it, not sure if I-Beam has a twisting problem (exception or rule), is this an issue.Are there different types of I-Beam, I believe the stuff I have researched is called Hot Rolled Steel, are there other types, if so are some stronger than others?I would appreciate your folks comments on my submission above, I will post a few pictures in this thread giving you some examples of jigs I have found on the web that demonstrate my details above.Working on cars and bikes is my hobby, learning to weld the pieces together is my quest.
Reply:Here's a shot (sort of) of a jig using the I-Beam option: Attached ImagesWorking on cars and bikes is my hobby, learning to weld the pieces together is my quest.
Reply:Here's a shot (sort of) of a jig using the 4X4 Box tubing option: Attached ImagesWorking on cars and bikes is my hobby, learning to weld the pieces together is my quest.
Reply:I like the 4X4 option, but it looks like a lot of work/welding, I think the I-Beam option would be a lot easier for me and would break apart very nicely when not needed so I could store it along the wall of my garage.Should I be concerned with I-Beam warping/twisting, are there various types of steel used in the I-Beams (if so which would be stronger/better)/Your thoughts would be appreciated, thanks.Working on cars and bikes is my hobby, learning to weld the pieces together is my quest.
Reply:As for leveling, I would have adjustment bolts in each of the 6 legs, I assume I would bolt all the pieces together (but not tighten them up until I level everything with the adjusting bolts in the legs), I assume that this would work pretty good (but I could be wrong).Working on cars and bikes is my hobby, learning to weld the pieces together is my quest.
Reply:I also found these clamps that would be great for holding the main tubes to the jig (they are available in aluminum): Attached ImagesWorking on cars and bikes is my hobby, learning to weld the pieces together is my quest.
Reply:Here's a possible leveling feature: Attached ImagesWorking on cars and bikes is my hobby, learning to weld the pieces together is my quest.
Reply:What kind of drag cars do you wana build?  I have built entire door cars off of nothing but jackstands.  The jig is nice for larger production work, but really its used only to setup the basic cage, then after the final welding the thing moved so much from warpage that the jig is useless and you just use the lower tubes as your level point. With that being said, the ones I have seen were I beam layed longitudinally and had smaller box tubing as your lateral supports.Syncrowave 350Coolmate 3Millermatic 251Spoolmatic 30A
Reply:>>What kind of drag cars do you wana build?>jig is nice for larger production work, but really its used only to setup the basic cage> then after the final welding the thing moved so much from warpage that the jig is useless and you just use the lower tubes as your level point>Respectfully, I think there's more to this project than you realize, and I suggest you do a bit more research before you 'dive right in' and start fabricating>A_DAB_will_do, you make a lot of good points, and have provided a lot of good information to ponder, thanks very much>When you get to Jerry's take a look at his jigs they are very large and heavy not sure a bolt together jig is going to be rigid enough to work<<Good point sir, I did take the I-Beam shots above from the Yellowbullet.com site, it's used by a chassis shop called Jakes Performance.Here's a thread with some jig examples:http://www.yellowbullet.com/forum/sh...d.php?t=122196Here's a gallery sequence from Jakes where he's building a car using the jig that is in my pictures above:http://www.jakesperformancefabricati...N6258.JPG.htmlRegards.Working on cars and bikes is my hobby, learning to weld the pieces together is my quest.
Reply:Here's one of my other projects on the go, lots of fun: Attached ImagesWorking on cars and bikes is my hobby, learning to weld the pieces together is my quest.
Reply:this has been for sale forever.http://minneapolis.craigslist.org/da...638963021.html
Reply:Urace, thanks very much for the feedback, lots of good advice for sure.Can you recommend a particular size of I Beam, also I assume the beam should be long enough to span the complete length of a race car (including bodywork), but I am no sure (perhaps you have some extensions that are added as needed to keep the basic I Beam length within some reasonability factor).Do you use any kind of additional beams or tubes that you clamp to the basic I Beam, to hold the main chassis tubes at various points too?A picture or two would be appreciated if you can at some point in the future.Thanks again.Working on cars and bikes is my hobby, learning to weld the pieces together is my quest.