6/1/2008: Mounting the Body to the Rotisserie
I’ve always known that I’d like to get the car on a rotisserie so that the underside can be thoroughly cleaned and painted and to make repairs easier.
I’ve been looking for a good deal on one, and last summer I came across one for sale locally on craigslist. It’s a heavy duty model 4000 pound model from Accessible Systems. It’s made of thick steel, and the only thing wrong with it when I got it was surface rust. I sanded it down and painted it in rustoleum at that time. I also cleaned up the hydraulic ram cylinders (which were rusty and pitted from being left outside) at that time. They still work fine, and can be replaced easily if they start leaking.
So for the last year this thing has been taking up a big section of my garage. After I found that the floor repair was dragging on because I was dreading working under the car, I finally decided to get moving with getting the car mounted on the rotiserie.
Some time back, a fellow member of the fiatcabrios mailing list, David Nicholson, had posted these pictures of how his car was mounted to a rotisserie.
I copied his basic design for my car, since it looked perfect.
The first step was to remove the front and rear suspension from my car, so that it was just a bare body shell. Several weeks ago, I went around loosening, oiling, and re-tightening all the subframe and rear suspension bolts, so I knew there would be no major problems when the time came.
So it was a simple task to remove them when I went to drop out the front subframe for real.
First step was to remove disconnect the tie rods and center steering arm. Pickle fork plus BFH.
Then I jacked the car as high as I could, and supported the body on jackstands placed under the body, rather than the subframe. I loosened all the bolts, leaving a few in the back until I could get the front 4 bolts completely loose.
Two of them were stuck in their sleeves where they pass through the subframe in the front corner of the car. I hammered on them a little with no luck, so I decided to just cut off that end of the subframe with a sawzall. It was no good anyway. After doing this, i removed the remaining bolts and lowered the subframe out of the car and onto a furniture dolly. I was able to slide it out sideways with no problems.
I think it’s obvious why this subframe is being replaced!
Once the subframe was out, I had no problem getting those remaining two bolts (and bit of subframe) off the car with a little assistence from an air chisel.
The next step was to remove the rear end. I first disconnected the shocks and sway bar from the axle (leaving them connected to the body, since they’d be easier to remove later)
I unbolted all the nuts and bolts on the front and rear leaf spring brackets, and planned to just lower the axle down on a jack. Well, no luck. It easily came down in the rear, but it turns out that the front brackets are not only bolted to the body with 4 bolts, but also welded, for some reason. I don’t know why the bolts are even there.So, change of plans. I had to remove the large bolts (through the spring eyes and these brackets instead. One came out pretty simply with the impact wrench. The other.. did not. It was seized to the inner steel sleeve of the bushing, and once the rubber tore, it would just spin all day, but never move. I had no choice but to break out the sawzall again and cut the bolt off.
Once that was done, the rear end came out easily:
Here are the brackets I made to hang the car. The front brackets are 3/16” wall thickness 2x2 tubing, welded to 1/4” plates with bolt holes. These bolt around a larger piece of 3x3x1/8” tubing, with 3/16” plates on both ends, drilled to match the subframe bolt pattern. (I used my new subframe as a template, so this was easy to prepare in advance).
I had them welded by a local welding shop (Standard Welding) because I didn’t trust my 110v MIG welder on such thick metal. (with good reason.. even with flux core wire, it has a lot of trouble penetrating more than 1/8”)
The rear brackets go under the rear valance of the car and connect to the leaf spring shackle mounts. I had the bushings pressed out of these mounts and then bought some 1 inch steel sleeves at a local hardware store, and cut them to size. I used 2x2x1/8” tubing to make a simple right angle piece. Since this material was thinner, I welded it myself. So far the car hasn’t fallen off the rotisserie, so I guess it penetrated ok.
As everyone always warns you, it’s critical to brace the door openings on a convertible. My door braces are thick angle iron welded to plates that fit the original mounting holes for the upper hinge and striker plate. I didn’t bother reinforcing from one side of the car to the other, the way David did. I didn’t happen to have a long enough piece of steel around, and I felt that it was strong enough without it. Maybe I was wrong :)
Here’s the car on the rotisserie:
Normally, you should try to balance the car so that it will stay in any position it’s left in without being locked in place.
I couldn’t completely balance because of the relative height of the rear brackets (which go underneath the valance) and the front ones (which are at grille height). The rotisserie lets you adjust the center rotation relative to the mounting point, but still I was at its limit in both directions and the car still isn’t balanced enough to stay where it’s positioned if you let go of it.
I suppose next time I’d make the rear brackets with two more pieces so that they go back up before connecting to the rotisserie, but I think that’s more complexity than I need.
I was able to get it balanced well enough that it’s not particularly unstable, and since due to my low ceilinged garage, I also can’t rotate the car completely over anyway, it’s perfectly fine.
I opted to rotate it as far as I can, and then use a safety chain so there’s no way it can fall, regardless.