Any pointers on what to or not to do as I am now starting to look at how I will shorten my chassis.
No pans on the car now and thinking it maybe easier to shorten and jig with them off.
Anyone made a jig or how did you do it.
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Hit the Resources tab above and open a CMC Build Manual. It's in their.
Geeze, I did mine so long ago that there weren't even digital cameras to capture the process. Mine is CMC so I followed their directions on measuring, cutting, and using wood 2x4s" to align the halves. I suspect you could make more precise cuts to the pan with it off so it would look better than just a diagonal cut across it. I used an oxy-acetylene torch to shape and weld the pieces together. I've seen online pictures of the floor pn cut in steps to align the pattern better than the diagonal cut.
I noticed Kitman has a version of the manual on his website too.
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@Panhandle Bob posted:Hit the Resources tab above and open a CMC Build Manual. It's in their.
I have read it twice now.... I just like to think rethink and research one last time before making such big moves.
If I were to do it again - I'd take DrClock's sage advice and find someone with a steel flat welding table or frame shop that could accurately make sure all was properly aligned and level. Wood 2x4s" from Lowes with carriage bolts seem a bit hokey! Plus an experienced welder would instill trust that it was done with proper penetration.
Momma's little baby loves shortening shortening
Momma's little baby loves shortening pans
Cut it with a swazall, you can use plasma, too
but don't try it with tin snips cause they won't do.
Oooohhhh....
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The Samba link shortens it 14.5" --- for a Meyers Max most likely NOT for a Speedster (pan would be too short!)
If I had it to do over I'd probably do the step version. Not the diagonal cut. The abrasive blade wheel on the circular saw worked great for straight cuts. Body saw worked good for the connecting cuts.
I would really try to free the cable tubes from the spine and just pull them out the end as you push the spine together. Splicing them inside the frame is a challenge.
@Wrenn Smith posted:If I had it to do over I'd probably do the step version. Not the diagonal cut. The abrasive blade wheel on the circular saw worked great for straight cuts. Body saw worked good for the connecting cuts.
I would really try to free the cable tubes from the spine and just pull them out the end as you push the spine together. Splicing them inside the frame is a challenge.
I have already dremmeled the cable tubes away from the main tube in order to slide them out. I am planning to do the fuel line new once in fall as well.
Circular saw is a really good idea for nice straight lines.
I did the diagonal cut version with about 4” of tunnel overlap on both of my builds. Most of the cutting was done with an angle grinder with a cut-off wheel. I installed the floor pans and welded them in when the pan was full length and THEN made the pan cuts to shorten it. I then welded the seams on both sides (top/bottom). I gas welded mine simply because I can gas weld WAY better than I can MIG weld. It has seemed very strong and I can’t discern any flexing going on.
Pulling the tunnel tubes out the back is best, because you can weld the tunnel back together with no hole on the top. Once everything is back together it’s easier to just re-tack the tubes to the pan at the rear and cut them to the right length coming out of the pan.
I also used the 2” X 4” positioning bars to get everything lined up and they seemed to work just fine - Ask at the lumber yard for harder wood to be more accurate. You could even make them out or maple or oak and a 1” X 4” would work just as well if it is hardwood with the bolts press fitted in.
I would install your new fuel line now, rather than later as you’ll have a big gap between the front/back ends of the pan to maneuver it around in as necessary to get it through the proper pan holes front and back. You could also upgrade the fuel line to 3/8” instead of 1/4”. I used HD semi-rigid 3/8” copper tubing for mine, not steel. Got some flak for that on here, but it has been great for over 25 years, now.
Just make sure you’re putting it back together on a level floor and that the holes through the 2 X 4 are really straight and a tight, press fit for the end bolts (tap them through the board) and you’ll be fine.
I got the pans up off the floor on equal-height Jack Stands and checked everything for true-ness about a dozen times before making the tack welds. I also used a laser level against some reference points to make sure everything was level before tack-welding anything.
Take it slow, measure everything eight ways to Sunday before tacking anything and you’ll be fine.
@Gordon Nichols posted:I did the diagonal cut version with about 4” of tunnel overlap on both of my builds. Most of the cutting was done with an angle grinder with a cut-off wheel. I installed the floor pans and welded them in when the pan was full length and THEN made the pan cuts to shorten it. I then welded the seams on both sides (top/bottom). I gas welded mine simply because I can gas weld WAY better than I can MIG weld. It has seemed very strong and I can’t discern any flexing going on.
Pulling the tunnel tubes out the back is best, because you can weld the tunnel back together with no hole on the top. Once everything is back together it’s easier to just re-tack the tubes to the pan at the rear and cut them to the right length coming out of the pan.
I also used the 2” X 4” positioning bars to get everything lined up and they seemed to work just fine - Ask at the lumber yard for harder wood to be more accurate. You could even make them out or maple or oak and a 1” X 4” would work just as well if it is hardwood with the bolts press fitted in.
I would install your new fuel line now, rather than later as you’ll have a big gap between the front/back ends of the pan to maneuver it around in as necessary to get it through the proper pan holes front and back. You could also upgrade the fuel line to 3/8” instead of 1/4”. I used HD semi-rigid 3/8” copper tubing for mine, not steel. Got some flak for that on here, but it has been great for over 25 years, now.
Just make sure you’re putting it back together on a level floor and that the holes through the 2 X 4 are really straight and a tight, press fit for the end bolts (tap them through the board) and you’ll be fine.
I got the pans up off the floor on equal-height Jack Stands and checked everything for true-ness about a dozen times before making the tack welds. I also used a laser level against some reference points to make sure everything was level before tack-welding anything.
Take it slow, measure everything eight ways to Sunday before tacking anything and you’ll be fine.
Appreciate your full response. I have to head out of town for a few weeks but when I get home this is the to do next.
Back in town and just fit the new pans in, not clamped or hammered or welded yet just and ground to fit so far. Wondering about the seat rails that came in them already though. Looks like I need to cut right through one wicjlh I don't mind but has anyone actually used these rails or should I just remove anyways? Heading back out of town so I have time to read and research more.
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I had the “el cheapo” pans from Lehigh Metals that did not come with seat bases or glides, so I never had to deal with cutting through them.
You might as well remove them before shortening the pan because they’ll never line up properly after the cuts, anyway.
Lots of seat glides are available from Hot Rod places like Speedway Motors or Summit Racing. They come in a bunch of different heights and glide styles for you.
Search for “seat slider”. Often, new seats come with sliders, too.
You won't use the rails - since they will make any seat sit too high. Grind the spot welds and remove them.