Cabriolet 68C Belt Line Wood
 

I am working on the wood for the top of the body at the belt line. I would like to know more information on the dowels that are used between the three pieces of wood:


1. What diameter dowels should be used?
2. Are the dowels glued into one or both or not at all belt line pieces?
3. How deep should I bore the holes into the ends of the belt line wood?
4. Any hints on how to accurately bore these holes to get a tight fit?


Thanks for your help, Ed

Re: Cabriolet 68C Belt Line Wood
 

A lot of the info I have found doesn't indicate that the three pieces were attached to each other. This may be the case but I'm not the one to be able to say for certain. The top bows were likely mortise & tenon jointed together in the corners but the tack strip may have not had a need to be. Some wood was structural but some may only be for trim purposes and mounting structure. The top center bow is a structural member for sure. A lot depends on how well the body lip where the tack strip mounts was formed. There are a few Cabriolet guys that frequent here. Hopefully one will respond.

Mortise and tenon joints can be difficult to fabricate and pining them with dowels further complicates that. The dowel bores and dowels require some accuracy in tooling to get good fit but ultimately, it's the glue that holds it all together that is the most important part. All the pieces just provide more area for a good solid glue joint.

Re: Cabriolet 68C Belt Line Wood
 

Hi, Ed...the original top bow wood pieces that I have (68B) are pretty chewed up, but it looks like the pieces were joined either with mortise and tenons of about 5/8" or finger joints, but unfortunately, I don't have any pieces left of the belt line rail.

Re: Cabriolet 68C Belt Line Wood
 

On both B&C the main tie-in on the belt rail pieces is the lower landau bracket
In both cases the bolts thereto pass thru the body also
It’s pretty solid once all that is assembled

Re: Cabriolet 68C Belt Line Wood
 

I hadn't thought about the way those landau lower brackets are shaped and placed underneath on the 68C. They would definitely tie the two pieces together.

Re: Cabriolet 68C Belt Line Wood
 

I do not think it matters much.

As pointed out the cast brackets are going to connect them together in any event.

It is important to remember to slant the wood more then 4 degrees forward so you will not get a line at the base of your top. The back of the top is angles 4 degrees (so I am told, not sure I have the data to prove it) forward and you have to allow for the bow drill which will be covering the wood.

To be sure with my car I mocked up the top and ran tape up and made sure the wood cleared this tape.

If you look at the factory photos you will find the wood may have been shaped after installation to the body. You can see one photo with the wood going straight up and another where it is shaped with a slant if I recall correctly.