Back in the "old days," many channeled bodies were joined to the frame by welding. This column addresses the downside of this approach and suggests a good alternative.

Q. I'm working on a '50s-era 1932 three-window coupe. It has a nicely done chop, filled roof, and it was channeled by cutting out the floor, dropping the body down, and then welding the body to the frame. The previous owner cut the body and frame apart, losing the rockers and the wood around the doors in the process. Needless to say, the body is rather limber at this point.

I'm concerned about getting (and keeping) the trunklid and doors in proper alignment. My plan is to put the doors and trunklid in place, tack-weld everything together, and then cross brace the body to maintain the proper shape while the wood is replaced and the floor's reconstructed.

My question is: How much clearance should I allow between the edge of the door and the doorjamb for proper operation? With the wood missing in the hinge area I have to reference everything from the latch side of the jamb. I'm thinking I should allow about 1/8-inch clearance, but that's just a guess.

Is this a good approach for this project, or is there a better plan?

Craig Layn

Via the Internet

A. If your body is already cut away from the frame, I would suggest building a new floor inside the body and bolting the body structure to the frame. While many cars were channeled by welding the body to the frame, I believe it's better to allow for disassembly later. This allows you to do minor shimming under the body-to-frame mounts to fine-tune the fit of the doors after the car is completed. If the body is welded solidly to the frame, you are giving up that adjustability. Sometimes just the weight of the engine and transmission can cause the frame to flex enough that the fit of the doors is compromised.

I like your plan to tack-weld the doors and decklid into place temporarily. I'd suggest setting them up with a 3/16-inch gap. When the car is painted, the buildup of paint and primer on the doors and jambs will leave you with a gap closer to 1/8 inch, which is the bare minimum I'd suggest. You can certainly build in larger gaps, which can help mask a less-than-perfect fit, but in my opinion, a 1/4-inch gap looks a little large on a car like a '30s coupe. (For comparison, if you look at the door gaps on '50s cars, they are usually around 1/4-inch, sometimes larger.)

Check the frame very carefully to be sure it is not crooked or twisted, and take the time to correct any deviations. If you don't have the equipment to do this at home, a body shop with a frame machine can help with this. Once you are satisfied that the chassis is in proper alignment, jig it up so that it is level, and at the proper rake.

Now you can lower the body shell over the frame and position it at the height you want. Go slowly here and measure everything carefully to make sure the body is aligned accurately, paying special attention to the diagonal measurements. Once everything checks out correctly, you can start envisioning the floor and how it will attach to the body shell. A good way to build a floor is to use rectangular tubing for crossmembers, perhaps 3/4 x 1 1/2 inch or 1x2 inch, and to build a perimeter structure from the same material that will rest on top of the framerails. You'll have to use some ingenuity to join this tubing structure to the doorjambs, firewall, quarter-panels, and the rear panel below the decklid. Once this structure is tack-welded together, you can use 16- or 18-gauge steel to create the actual floor.

If you are into the project this deeply, I'd encourage you to replace the wooden structure with metal tubing, which will be stronger and last for the life of the car. Wood is likely to lose its integrity at some point in the future.

You can email your questions to Professor Hammer: covell@cruzio.com or mail a letter to Covell Creative Metalworking, 106 Airport Blvd., Suite 105, Freedom, CA 95019. You will receive a personal reply. Ron Covell has made many videos on metalworking, and they can now be streamed or downloaded from his website. Check these out at covell.biz, along with his ongoing series of workshops held across the nation, or call for a current schedule of workshops and a free catalog of DVDs. Phone (831) 768-0705. Also, check out Ron's YouTube channel: www.youtube.com/user/covellron.