M18 Paracaisson Cart Restoration - Help Needed

[Quest Master]

I am about ready to start the body restoration of my M18 Paracaisson, as seen here: http://www.questmasters.us/M18_Paracaisson.html

The aluminum body has some huge dents in it.....huge. My question is: what is the best way (and easiest) to remove these dents. Using a body hammer is not a good option as the body is corrugated. Has anyone had a die made and used a press to remold a body like this? Would an English Wheel work? Comments please. I do not want to leave the dents as the Paracaisson will not go back together correctly with them.

Original pictures of the M18 would be greatly appreciated. I am also looking for a lid and some other small parts to include the inner rack.

[Steve Webb]

For what it's worth I made the tunnel (where the tranny/transfer goes to the rear) on my 3a. I got the profile I wanted and then made sections out of wood that I cut on a bandsaw and glued/screwed them together. I then clamped the metal and formed it over the wood until it conformed. It turned out pretty good. Those contour gauges that have the steel needles carpenters use to get a profile may work to get a shape of a good section to make a wood block. it would be an in expensive attempt and sure wouldn't damage anything.Here is the gauge I am talking about

http://www.homedepot.com/buy/tools-hard ... 15132.html

[retro-roco]

Building on the idea from the last post, I suggest the following:

1. I presume the huge dents you're referring to are the areas where it bulges out between the mid reinforcement and the end caps.
2. I presume that the corrugations are relatively unmolested very near the end caps.
3. If you can remove the end caps ( I think you already have??) you need to trace inner profile onto a piece of wood that you can cut to form a sheet metal "buck" or "hammerform". This would preferably be hardwood, and can be made of multiple layers to create a buck several inches thick.
4. You'll also want to create a "die" stamp by tracing a portion of the outer profile. The die only needs to be two inner corrugations and the outer corrugation between them. will look something like \/\/.
5. Secure the hammer form in a large vice, or anchor it to a good solid workbench surface. Place the caisson over the hammerform, taking care to center it over the form, and with the corrugations aligned with those of the hammerform.
6. Working back and forth along the center line of the caisson, use the "die" you created, and a dead blow hammer to slowly and carefully restore the corrugations. Continue the process, slowly working out from the centerline,and toward the out edges. It is critical that you take your time, and ONLY hammer over the buck. having it underneath will help to insure that you don't end up dishing the caisson in.
7. It would also be helpful to use a steel straight edge along the length of the caisson, to help you gauge how bowed or straight it is.

Probably clear as mud... if you need it, I can put together a sketch of the busk and die I described above.

Good luck!

[Quest Master]

Thanks guys! Yes my M18 is completely taken apart, this is the body:



It looks like it was used to haul large stones or gravel. The body is very VERY bad. I did not think of making a hard wood form to beat the dents back out. That may indeed work easily since it is aluminum.

I am of course open to any other ideas.

[Steve Webb]

I believe it will work quite well for you. I would try to get the forms as wide as you can so you don't create a crease on a thin edge. Something 4-6" wide would let you work a decent amount but allow for mis hits and you can slide it as you go. Keep us posted.

[Cyclefreak13]

One thing I have done is to use a piece of pipe longer than the body, probably 1/2"-3/4" black iron. Clamp it to the body on each end and work each rib with a body hammer. Clamping it to the body will also straighten out the ribs so they dont dip in over the length. Just know that you will need to go this on the inside and outside of the panel. Time consuming but works out nice.

Devin

[retro-roco]

This is a quick sketch of the inner hammer form that I tried to describe above. I've shown it built up of approx. 6 layers (1-1/2 in thick per layer), but it would not have to be that many... 4 plies would be 6 inches of hammer form, the 6 plies as shown would be 9 inches. As I described above, the best place to get the most accurate, and closest to original profile will be near either end, where it was captured between the end pieces.

[Quest Master]

So this is what I came up with for the M18 body. I will post pictures of how it worked out!

[retro-roco]

Holy Cow!! Nice tool...

[Steve Webb]

This wood butcher says you are going to have a good looking cart body when you are done.