Here is a video of a custom back half and four link plan I am working on. I am hoping to get some feed back on the link geometry. Hopefully in the next day or so I will have the model converted to .pdf and I can share some clearer pics with everyone, but for now this will have to do...

http://s654.photobucket.com/albums/uu263/firepowerwelding/?action=view&current=MOV01112.flv

 

Alright, I got the drawing converted into .pdf files. Let me know what you guys think! The upper links are 1.5" .120 wall dom and the lowers are 1.75" .120 wall dom. The cylinders represent the bags fully compressed to 2.8" plus I gave them a little extra room (about .25"). If you guys are curious about any of the other dimensions just ask. Thanks for checking it out!

 

hey dan it looks pretty good!

the only thing i would chime in on is with the front upper bar tabs being so close, will a bolt fit in?

and i personally would go a bit heavier than the .120 on the lowers. unless you run some truss style plates on the bottom. they may work with the .120, but since all the weight is on them i'd go a bit heavier. maybe .188??


and i'm currently planning on stealing your 4 link mount crossmember design...

 

love the design, just a quick question though, are the bags going to actually sit that far over on the bar?

 

looks great
but if the bag is gunna sit that far out i would use some .25 2X2 and then use a cup to gusset it
also the bolts through the tabs is about it
other then that looks good

 

That cool that you can do this drawing /computer stuff ( nice being young & knowledgeable) , & great to see that you are forward liking ! As this is the right way to do this !

 

About the bolts/tabs too close... Duh... It's the little things that elude me sometimes. I'll get it straightened out. I just need to decide if I want to move the whole uppers out and maintain the angles they have or go with a little less angle and just move the front mounts.

As for the 1.75" tube, I agree really. I just happened to have some 1.75" .120 wall around the shop still from some tubing work I did on the '79 and thought I would try to use that, but I think you are right and I will go heavier.

Hey, that's great! If anyone wants to use any part of this that is fine with me.

Yeah, the drawing is to scale, just as I was planning to run it. It does seem a little wierd, huh? I kinda just based it off of this basic design:
http://www.suicidedoors.com/4-link-kits/thorbecke-brothers/super-lift-triangulated-4-link-kit
Although it does look like mine might be excessively offset. I'll check the clearance I need for a socket to get on the bolt in the center of the airbag mount plate.

Yeah, I agree about the square tubing. I am going to do that. I was already looking at squaretubing lowers as pictured in the kit above. I am gonna go back to that plan.

Hey, thanks for the compliments! I appreciate it! I also appreciate everyones feedback! this is going to be a much sweeter setup with the input from all of you! I agree so far with all the advice given and I am going to adjust the drawing accordingly.

 

I started fabricating the back half today. I got the frame rails started and the cross member all welded up. I am going to have to get a little more 2x3 x.12" tubing in to finish it off. Here's the pieces for the cross member. I did bevel them prior to welding after I shot this pic.

Here's how I jigged the crossmember up for welding. These 90 degree jigs are a must have for fab shops IMO:

I thought this was a cool pic of the frame rails:

And here's what I got done today:

 

It's rediculous how good that looks. Keep it up man. And we want to see pics at every step of the build.

 

what program are you using??
did you take CAD classes??
i got an auto cad software but ***** its so confusing

 

by the way good job

 

lookin good, the lowers just looked a little weird to me because wenever ive seen bags on the bars that have the bag plate almost dead center on the bar but have the plate lifted up enough off the bar so that you could get a wrench between the plate and bar. ill see if i can find a pic if im to confusing

 

Wow, thanks a lot for the compliment! I will definitely keep posting up the progress!

That's AutoCAD 2005 in the video. They made somebig changes for AutoCAD 2008 so if you are able to, I'd try to learn on that or newer.

I haven't had any formal training. When I first started I bought a book like this one:
http://www.amazon.com/Teach-Yourself-Auto-CAD-2007/dp/007149085X
I would actually highly recommend starting with a really simple guide like that one. There are much more in depth books, and by all means get one of those too, but for getting a basic feel for things, the teach yourself book is pretty good. I can't get into those books for dummies...
AutoCAD can be really intimidating at first, but once you get to know it, it is a very fast and efficient way to draw basic shapes and line drawings to scale in 3D. I have been working with autocad for about four years now.

I did actually adjust the plans to bring the bag plate a little closer to the center, but if you check out the superlift kit at the suicide doors link above, you'll notice it is pretty offset to the side so I am thinking it will work. The problem I had with raising the plate up wasn't getting a wrench into it, it's getting a bolt into it. I don't want the bolt to be captive and I don't want to raise the plate high enough to clear a bolt. I could still adapt it if need be though.

Thanks a lot for all the input and for checking out my work guys! I will try to find a way to get the most recent drawings uploaded. It's looking really good, but the pdfs have exceeded the boards upload capacity for files of that type.

 

Well, I couldn't get very nice looking .bmp or jpegs out of my drawing, so I made up a new video. I think it worked out pretty well.
http://www.youtube.com/watch?v=AYKPdEGtCbc
I put some more detail into the drawing. The rims are style basically like my is300 rims but I drem them in a 20" size. The lowers are now 2x2x.190" wall and the uppers are 1.25" .120" wall DOM. I am not actually going to have rod ends on both ends of the uppers as it is shown in the drawing, but they will be on the axle side. The lowers I haven't decided yet. I might do some kind of johnny joint setup on the axle end of the lowers if I can afford the parts. I also have to make sure I can find a way to mount the shocks with enough travel to make it worth while doing some kind of johnny joint or rod ends on the lowers.