'34 Plymouth RPU Update - Body Substructure

My steel tubing will FINALLY be delivered tomorrow after a long wait-1" and 1 1/2" square. The bodyline at the bottom of my cowl is just right for 1 1/2" so I will use that to form a "rocker panel" of sorts.

This piece of 1 1/2" will extend appx. 18" behind the doors.

You can see the rear kick-up or "Z" in the photo above(the patches weren't welded in at the time of this photo). That's how far back the cab will go. I am using junk doors to fab the 18" panels behind the doors.
These old Mopars had suicide doors, and I will weld 1 1/2" tubing up from the rocker to form a "door jamb" to mount the hinges.
From the rear "door jamb", back 16 1/2", and around to the other side will be 1" tubing. This will form the backrest, or "rear cab wall". I am thinking the back of an S-10 or similar small truck with ribs already stamped in. Will need to be at least 48"-the width of the cowl-or maybe the rear could flare out 3 or 4 inches on either side. Sure would make it better for seat room.


I also plan to replace the wood that goes up the doorjamb into the windsheild post(which have yet to be welded on)with steel. (See pic above) You can see the 1 1/2" pocket along the bottom of the new patch panel(where the "rocker panel" will start), and how much of the old one was rusted away!

Other side of patch.

The old wood is about 1 3/4", so I will use 1 1/2" tubing, tied to the "rocker panel", and add some 1/4" flat bar to make up the difference. This will also give a thick cross section to thread holes and mount bearclaw door latches.

This vertical tube will go all the way up the windshield, and both sides will be tied in at the top with 1" tubing. Hopefully, this will be strong enough to put a handle on top of the windshield frame to help climb in and out, as the seats will be back behind the door opening, and the suicide door will be in the way of my feet!

The reason I am posting all this beforehand is 1. To help see it in my mind, and 2. Do you guys who have been here and done that think this is a good plan? I am hoping I will get some feedback before I start cutting steel tomorrow.

 

Also, suggestions on thickness of sheetmetal for the floor.

 

lookin good Richard D.....I would use 18 gauge. Have used 20 but under structure is a must. Gotta bead roller? Also, you said junk doors....you wouldn't happen to have any left over driver side door hinges would ya? my coupe has some not very nice home made ones!

 

Yeah, I have a bead roller. I will be building a 1" tube sub-floor, and I have a sheet of 20 gauge.
As far as door hinges, I don't have the doors yet, but all my hinges are spoken for, I traded them for a hidden set.

 

Richard.. 18 ga. makes for a good floor.

 

Your project is really moving.. I love it...

16 ga is perfect for a floor if you don't plan on bead rolling it or overdoing it with the substructure. Anthing less than 16ga should be bead rolled for stiffness, thus preventing the oil can effect. I used 16ga on my T and i'm very happy with it.

Also - the wood in your front door jamp shouldn't be structural, at least it's not in my DB truck. I believe it was only used for the interior panel attachment, it's only like 1/8" thick. By the way, my wood had worm holes!!

 

ps - i wouldn't suggest 20 ga on a floor.. great for body panels but really too thin for a floor, i wouldn't suggest it. i'm sure you'll find a use for the 20 ga with all the patch panel work you need to do

 

Problem is my Chinese junk Harbor Freight 3in1 tool is rated for 18 gauge, but broke in half shearing 20 ga galv. The brake and slip roll still work, but I'm afraid to use 18 ga. Also, my bead roller is rated for 18, but I am afraid to use it to full capacity.

 

That harbor frieght 3 in 1 does suck.. My buddy ended junking his and getting a grizzly (that sucks just a little less).. He still uses my big federal for anything heavy. You should be ok breaking 18ga if you take it easy on the machine. SHearing requires alot more force than braking, that was the first thing to go on his machine as well.

That HF bead roller can definitey handle 18ga as is (it's it's the bench one made of 1/2 inch plate). There are some posts on here and other forums on how to increase it's stiffness by strapping the top and bottom with square, plate or channel. It will take you about an hour and about 20 bucks in steel and greatly improves the tool...

 

Yeah, that thread kicks ass, I want to do something similar to mine, it is the 1/2" thick model.

http://www.jalopyjournal.com/forum/showthread.php?t=137858

 

OK, got busy on the Plymouth tonight. First, I cut some 1 1/2" square tubing to length for my "rocker panels". 1 1/2" was slightly too big. Kids, dont grind with sandals on!

First I mark it, then out comes the cutoff wheel.


Time to try my hand at hammer-forming.

I clamped a piece of flat bar right before the radius of the bend(which you can't see-DOH!), then hammered away!

Not bad for a first timer. I worked it a little more with the hammer and dolly after un-clamping it.


Here's how it came out(sorry for the blurry pic). Once I clamp it and weld it, it ought to be O.K. There's a few hammer marks on the bottom, but when was the last time you looked at the bottom of a rocker panel on a rod that gets DRIVEN and it was perfect?

 

The front edge was not re-shaped to fit the tubing. I am wondering what to do to re-shape this part, if anything. Hard to tell from these photos, I'm no photographer, but the difference is very slight. I may be the only one to ever notice it, because this thing will be LOW.



I'll decide after I weld it up.

 

Here's some more pictures of the gap.



It ain't much.

 

Then, I started cutting out the wood and support underneath.


It was originally quite strong, the wood was thin, as stated above by Rodwerkz. If the bottom hadn't been gone, and even more importantly, if I'd known what a bitch it would be to cut out, I may have done it differently.

The vertical will be mitered to fit better before welding to the "rocker panel", and gusseted. A smaller piece of tubing will be welded in front ot the 1 1/2", and to the existing brace seen in the pic. Here you can see the area that wasn't modified, as mentioned before. I may weld a piece of flat bar underneath to make up the difference, or not. 1" tubing will be welded up the firewall, along the top of the cowl, and back to the dash in a cage shape. This will support the cowl steering.

 

wow.. nice work.. I like how you cored the front jamb with the 1 1/2 and tying it into your rocker. Do you mind if i steal this idea from you? I'm giving serious thought to making my rocker structural like yours after seeing how you've done this..

Again, nice work..

 

Of course not, that's why I posted it. Keep watching, I'll do more tonight.

 

Cool looks you are making good progress.

 

my jambs are in useable condition but are rotten for the first 3". I was going to replace just that section by triming up a piece of 2x2 square tube to fit the profile of the jamb, but i definitely like your solution better...

 

The three main reasons I am going all the way up the doorjamb to the top of the windsheild are,
1. The windshield was cut off and I have one from another car to weld back on.
2. This will be a roadster and as such, will not have the extra rigidity of a roof.
3. I know people (myself included) will end up using the windsheild frame to help climb in and out of this thing, so I want it as strong as possible.

 

After trimming the inner structure out, the 1 1/2" is a friction fit, I got lucky on that one!

 

That's some fine looking welding and panel fabrication Richard.

 

You should know!

 

Finally got out in the garage and did some more work. I had to wait on some 1 1/4" tubing. I got the winsheild post carved out (bigger pain in the ass than I would have thought!), the brace tacked in, and the post tacked on.

Damn, those are some gnarly lookin' tacks! I'll get somebody good to finish-weld it.

I will pie-cut the rocker panel tube to follow the curve on the bottom of the door.

Here you can see where it goes up the doorjamb into the windsheild post.

Outside view of the post.

There will be some fit and finish work to be done here to make it fit, as these posts came from a different car. It will be a little shorter, and a tube will run across the top. This will be hidden under a Model A visor.

 

Can anybody recommend good quality latches? I have about 2" of depth to work with. This is a good article, but I don't want door handles.
http://www.jalopyjournal.com/forum/showthread.php?t=101044&&showall=1

 

looks awesome man! unfortunately i got a little sidelined by some updates to my T but will get back to the dodge soon enough.

For door latches I'd recommend the small bear claws. I used them in my T and i was very impressed with the quality and function.. I think I bought them from auto-loc. They were pretty reasonable too. I don't use door handles either, i just have a little pull sticking up through the door lock slot. I'll try to post a pic tonight.

Try not to use anything iffy or any bear claw knockoffs with the suicide doors. If they pop while driving you'll have an ugly situation.

 

That is EXACTLY my concern! As hard as it was to find doors, and as much work as this is turning out to be, I don't want a door to get ripped off and end up in someone's windsheild at freeway speeds!

 

yeah... the latch and stricker mechanisms in my dodge are in suprisingly good shape considering the shape of the rest of the truck. I may try to use them and then go with a redundant deadbolt type lock like the ones they make for streetrods. My buddy has em in his glass 32 3-window and i like the way they work... I'll probably machine my own though to avoid the billet look.

 

Very good idea, I don't know if I trust just a latch, no matter how good it is! Got any more info on this type lock?

 

I know http://www.outlawrods.com makes em.. Their website sucks though...

 

here is my bearclaw install. i essentially cut out the stock pocket and made a filler plate to fill it in and hold the latch. That silver piece sticking out of the door lock slot attaches to the release. Pull it up and the door pops. i hope to make something a little more cosmetically pleaseing one of these days but you know how that goes.