lower section of wood frame

Post by **mikeyr** » Wed Feb 02, 2011 11:47 pm

ok, I have struggled and spent WAY MORE hours on this ONE piece of wood then should ever be spent. On the bottom of the LM body is a single piece of wood that goes from the front cowl to the rear fender. Its a compound curve, both vertical and horizontal and that wood is missing from both sides of my body (one side was replaced with angle iron). I can easily figure out the vertical curve by following the body but the horizontal curve I can't seem to guess or figure out. I know it has to follow the frame to some extant but what little wood remains on the doors indicate it has a inward curve, so its not a straight line following the frame. My concern is that on the vertical curve, the end near the rear fender goes flat and up in front of the door where the cowl attaches changes and curves upward even more so the 2 ends don't match on the vertical curve. I have NO way of knowing what the horizontal should look like, I can match the door curves somewhat but my left door is in bad shape and distorted and the right side is even worse from a accident decades ago so they don't match side-to-side, I can guess that part if I have to. Any one replaced this piece yet and has a pattern ? (by the way, i am tracing all these pieces and will have drawings scanned and posted here in the next few weeks of the entire body)

mothy · Post by **mothy** » Thu Feb 03, 2011 12:12 pm

Maybe these pictures will help a bit from my 1934 SLM.
I can try to take measurements if you wish.

Roly

Post by **mikeyr** » Thu Feb 03, 2011 5:33 pm

Yes, the pictures do help, it appears to be straight behind the door to the rear wing and the curve appears to be only at the door area, is that about right ?

mothy · Post by **mothy** » Thu Feb 03, 2011 6:51 pm

Yes it is straight behind the doors.
I have redone the one picture as it was truncated on screen and did not show the wood.

Here are a couple more, I have lightened the pic a lot to try and show the gap of the straight edge.

And yes it is rather dirty and muddy!

Front of door is on left of both pictures

Roly

Post by **mikeyr** » Thu Feb 03, 2011 7:55 pm

Think I will just go "straight" with a slight curve where the door is. The back part is easy to guess and also fix if I guess wrong, the front cowl area is the concern since I don't want to curve that area too much. I think I will just match it up the main beam that follows the frame so so only curved where the door is. And when I build the doors I will try and match it up since both my doors are different now anyway.

Peter McKercher · Post by **Peter McKercher** » Thu Feb 03, 2011 10:38 pm

Good call Mike. I just checked mine as it was quite a balmy day in the garage today (9 degrees f - T shirt weather). The section is made from 2 pieces - one short one at the front and a long piece which goes under the door and bridges the door post (Rabbet) and the bottom of the wheel well arch (Lap joint). The long piece is curved under the door, as you know, but is straight between the door post and wheel well arch. Ditto the small piece at the front between the two cowl members. It is straight, but I seem to recall that the Rabbet joints weren't 90 degrees. You'll be able to determine that when you test the piece.

armsid37 · Post by **armsid37** » Sun Feb 27, 2011 9:31 pm

Hi Mike.

I don't know if this will help, however this is what I did.

Although I found some ash I could not find size suitable for that bottom frame, so I decided to laminate the thing using thin marine ply and marine glue.

I had the remains of one side from which I drew up the shape, made up some brackets of sufficient height to allow shaping and duly progressed. To create the other side I just used a mirror effect.

The fitting was testing on both my patience and my knees none the less I and satisfied with the result.

The attached pics indicate the process, for the outer shape a central pivot point some 600mm from one end and 500mm from the other and then 45mm from the end points of a straight edge worked OK. The inner curve was shaped in the fitting process.

Brian.