Roof building when joining cabs

[rcurrier44]

Well I have learned a lot by reeding this site but I have a question for the masters on witch way I should approach a section of my project.

I am about ready to start cutting on a set of 61 chevy trucks in order to make a club cab 61. By delime is with the roofline and how to join the 2 cabs smoothly.

http://pages.zdnet.com/64moneypit/sitebuildercontent/sitebuilderpictures/darylva60.jpg

As you can see from this pic the roof line slopes from the headband style body line in the rear to the front in a consistent lowering slope. When I fit these 2 cabs together I am going to leave the body line at the rear and cut the front cab section right in front of that body line. Then I want a fairly smooth flat top above the rear door area.

This fellow (willys36) Did his by putting two sections together and left a low area.

http://hotrodders.com/journal_photos/00002439/10839915200.jpg

Then he went back and cut a filler panel into that area.

http://hotrodders.com/journal_photos/00002439/10839915201.jpg

I don't thing that is the best way and would like to avoid this extra step.

I was thinking I could stretch the front portion of the rear cab up to meet the rear of the front cab....but I fear it is going to be hard to get it to rise up that far and keep the rest of the panel flat and straight. Or I could cut everything out forward of the body line on the rear cab section. Then make a new panel to put in its place. This panel should be fairly easy to make because I would be cutting both roofs at the same spot (just in front of the body line) and the panel would evenly bend down to meet the rain gutter on both sides. The drawback would be that I would have two weld seams in the roof instead of just one. unfortunately I don't think I have the skills to be able to form the entire roof out of one piece of steel like the aftermarket conversion companies you see do it.

Thanks for your input

PS the spell check on here rocks...I am an engineer and can't spell anything to save my life. Having it right there in the web site is nice. :D

ROB

[Gonejunking]

Hi Rob
Welcome to Metalmeet!!
My son has a truck just like your's.
We had talked about making a crewcab out of it. I think you would be better off making the roof 1 piece, rather then trying to cut and weld the 2 together.

Just my 2c

[rcurrier44]

Wow you would. How would you go about doing that rear body line area? I can do the front and sides no problem. But I can't see how you can keep that rear band across and curve the sides down without distorting the band you already have.

Or are you thinking of fabing the hole front and mid section then joining it to the original rear band area just in front of the body line. I feel confident I could do that.

Thanks
ROB

[Tony Sanchez]

---Rob,
Your second idea would work best.

"Or I could cut everything out forward of the body line on the rear cab section. Then make a new panel to put in its place. This panel should be fairly easy to make because I would be cutting both roofs at the same spot (just in front of the body line) and the panel would evenly bend down to meet the rain gutter on both sides".

As long as you can get to both sides of the weld to stretch and planish you shouldn't have any problems. I would make my weld just above the rain gutter in the curved area, there would be less heat distortion problems.

Please send photos of your progress, we like photos.

---Tony.

[qwantus]

I'll be real interested in the progress of this topic. I too have a truck that I would love to extend the cab on and still might.

http://www.metalmeet.com/forum/viewtopic.php?t=1521&highlight=

Randy D.

[rcurrier44]

Tony, I think you might be right that that setup would be the easyest....mostly because the part I have to make has the same section all the way along it when viewed from the front. I do worry about being able to keep the surface flat and stable because the roof area is going to be much larger and will be smooth till the body line in the back. I think I will end up doing something like this to give it some rigidity. I can just see taking it on its first drive and the roof popping in at highway speeds.

http://hotrodders.com/journal_photos/00002439/10839888960.jpg

However I would waite till I got the roof surface done and could see how weak it real was going to be. Even then I don't think I would weld it to the roof. I would probably epoxy it up there to keep from warping the metal from welding.

I am going to be able to get to the bottom side so I can planish after welding. I plan to make the inner roof area a drop out rectangle along the factory rolled beads that are in the roof right now. There would be one above the drivers and one above the passengers area. To finish them off I will cover them in the same material as the seats (cream colored leather). That way I can also add insolation inside the roof area.

I'll be sure to take lots of pics as I go from step to step putting this thing together...this is going to be a very long term buildup.

[rcurrier44]

Well I have seen pics with them set up both ways and I like the smooth top till the back look better. Having the body line in the middle however would give me a much stronger roof.

Here are a couple of modded pics that I have done showing what the bodywork should end up looking like. It will however have a 61 hood with a fleet side bed + the factory step side fenders added as duley flairs. The truck is being set up to tow our show/race car around.



http://www.m4x4a.org/ImageGallery/album129/4_door_5.sized.jpg

http://www.m4x4a.org/ImageGallery/album129/4door2.sized.jpg

[Tony Sanchez]

---Rob, I agree that you will probably need some bracing across the roof at the B pillar. I have fabricated some channel type bracing for the underside of a hood and also a deck lid. You could also use wood for a brace.
That is an interesting looking project, lots of work but well worth it.
---Tony.

[abonecoupe31]

Your project has me wondering also--as I've often thought of joining two cabs for a crew cab.

I'm sure that with some junkyard searches you could get the roof section from a similiar GMC or Chevrolet Panel Truck or maybe a like year Suburban--and just graft in the desired length of that roof. Those bodies are similiar and use the pickup front clip....

Buying what you need instead of using what you've got...

Just my two cents worth.

Mark aka Abonecoupe31

[Ron G]

Abone
you beat me with that answer. That would be my solution also as it would have all the right bends and curves and probably several cross braces.
There is a one ton dually push truck that comes to the salt flats from Texas that has three doors on each side and a pickup box, COOL. The license plate says Texas and the personalized plate says LIMO.
Unless there is sentimental value to this pickup it might be easier to locate a 4 door carryall and put the cab back and box on it. At least you would'nt have quite as many frame and sheetmetal problems.
Just my 2 cents worth, which is about all it's worth.

Ron

[geoking]

I built a 48 like this and the issues I had were"torsional". IE: When I drove straight..no issue at all! If I turned the truck while going through a dip like a curb gutter, the whole bodye wanted to twist. I had a very , very stiff frame made from scratch with heavy guage tubing by Fat Man Fabrications and it was not my issue. I mounted the body on shackles/ pivot points like the original mounts. just more of them. BAD IDEA! Over time the body flex popped paint off in a couple of stress points and the door alighment became an issue.
My feedbac is not how to, but how NOT too! smile I thought letting the whole body "move as a unit" on top of the ridgid frame would work. It might have had the body been stronger.
Regards,
George

[norm47]

I'm getting ready to cut my 46 chev pick up into a cab and a half(17" extension). The frame will be streched also, and will be very stiff.
George- Are you saying that we should consider bolting the body to the frame "real good" instead of letting it float like it does stock? I figured letting it float would be better, but your experience says something else. Can you expand on your reasons. Thanks

[gregfri]

This is a subject that interests me as I have built a couple of extended cabs out of old trucks.I built mine before I knew much about metal shaping, so I used a lot of exsisting parts with the right shapes. I don't know how to add pics to my post, but if anyone is interested in seeing my projects you can see them here http://community.webshots.com/user/gregfri The 48 Chev extended cab is my current ride. George- do you have a picture of your 48? I would be interested in seeing it. Greg

[geoking]

Norm,
YES , I would mount it with rubber bumbers for vibration dampening just as other bodies. AS a matter of fact , I can not think of another vehicle that I have ever had that is not mounted directly to the frame with rubber mounts.
THe floating mounts on the 48 crew cab just allowed too much twist...
I will dig up some pics to post.I do have one other horror story..
I ordered this great rol pan for the rear of the truck under the tail gate. I was so happy to be almost through. I put the entire bed together including the roll pan and had a friend help me lift it up [less wood] and put it on the frame. the dumb roll pan ...uhhh the dummy that put the roll pan on didn't allow for the frame length. No issue at all...I grabbed my saws all and just cut the fram off 2 incheson each side. Great ..lets mount this baby.....well duh...I just cut the rear mounting holes of and the bed had NOTHING to rest on at the rear. I was so upset that it all sat there screwed up for 3-4 weeks while I nursed ny ego. WHat I should have done is cut the frame at an angle to allow the roll pan clearance. Solution, weld the pieces back on,,,grind... smooth and recut at a 45 degreecut from top rear of the frame to bottom front,.
OK everything fits... repaint the once beatiful frame and start again.
sigh...what is the old saying ? measure twice ..cut ONCE. smile. George

[Wray Schelin]

1940- 48 Lincoln Continental all steel body's are welded directly to the frame.

Most wood framed custom bodies from the 1930s are bolted right to the frame insulated only by thin rubber pads and shims to eliminate squeeking and to align the doors.

Rubber isolated bodies mounted on full frames were mostly mass produced bodies from the 1940s through the 1970s.

[Avalonjr]

Greg,

I looked at your pictures. It looks like a fun ride. How long did it take you to do?

You did pretty well for saying that you just assembled parts... I should be so lucky.

[Dutch Comstock]

Original pickup trucks were made to be very flexible and the frame was made to torsional twist.The movable suspension arms at the back of the cab kept the bady from tearing up when the frame twisted.Now that you are adding length to the wheelbase you should box the frame so that it wont twist and then go to direct rubber or ureathne mounts so that the frame and the bady will work as one unit.
Also one of the easier trucks to stretch is the 60 to 66 chev truck bedause of its basic box design.The more shape that you have in a truck the more work making custom body panels to blend the body together.They are real neat when they are done but require a lot of thought and a lot more work than can be imagined. Dutch

[norm47]

Most big rig semis have the cabs mounted in front , then have air bags with a small shock under the cab in back. Now these frames are not boxed, but I assume they are very stiff due to thickness and frame height. Some I think are also heat treated
The frame under my 46 Chev pu is not boxed , but I was going to fish plate,and box in the area of the extension. I was also planing an extensive "x" member to create frame strength and stability.
Do I have blinders on or what? Why won't this work? OOOORRRR, do big rigs mount this way because the frames DO flex and twist?
Sorry, I didn't mean to change the subject of this thread, but sometimes my mind wanders a bit.
Thanks

[gregfri]

Greg,

I looked at your pictures. It looks like a fun ride. How long did it take you to do?

You did pretty well for saying that you just assembled parts... I should be so lucky.


John- this project took 8 years from when I started till I acually drove the truck on the street.During this time, however, I built a new shop,had a major flood in our area and had to rebuild my house and yard, raised two boys, tried to make a living, and built about a dozen street rods for customers. In reality, I built about 75% of the truck in the last winter that I worked on it. I am hoping to finish the interior this winter, Greg

[Avalonjr]

Norm,

I think the reason a semi rig has a shock mounted cab is for the comfort of the driver. Usually semi's are spring loaded without shocks. Depending on load, the ride can be pretty bad. In addition to shocks and airbags on the cab, the driver usually sits in an air ride seat which can move up and down about four inches.

It is possible on a rough road to hit a harmonic between all these suspensions. I've hit my head once or twice.

[Ron G]

The semis with long cabs also have rail like reinforcments under the cab to make it stiffer. The frame can flex, and does very badly, due to engine torque with a poor driver. The frame twists and the cab leans but doesn't twist much. The older trucks with seperate sleepers were mounted on rubber. They had a joint betreen the cab and sleeper so they could flex seperately with the frame.
I would sure be tempted to make sure that your cab floor had more stiffeners than a single cab and then mount it on the arms in the back.
Just my nickels worth (inflation)
Ron

[Korey Wood]

I'm with the Suburban roof idea. I would turn the roof around so the slope in the roof faces the rear and cut the raised part of your 61 roof out about three inches all the way around and add it to the back of the Suburban roof. Alot less fab with a pleasing result. Also consider that when you go to shorten the Suburban roof, notice where the roof braces are and see if there is a way to cut the Suburban roof in such a way that as many of the braces are kept as possible to support the length. Dutch is right on about it being more work than you think. Lots of planning will save you tons of frustration and hours of rework.
If there are any braces leftover after you cut the Suburban roof ..consider cutting the spot welds and reusing the brace to bridge the slices in the two sections and then rosette or spotweld the brace on either side of the slice to provide maximum support for the new roof graft..,Sweet lookin' hauler... PLease keep us posted with any progress or challenges you face along the way,

Korey Wood

[rsanter]

I would think that rubber mounting is best. also, I would think that a 3 point mount system instead of the 4 point may be better. attach 2 points at the front and one at the back and structure the floor of the cab to handle that loading

bob