Building a tube frame crawler from scratch

[Ampdraw]

Where do you guys start when you do these?

I have a chop saw and a 240V stick welder I'm pretty good with, I'd buy a tube bender, but beyond that despite how badly I'd love to build one of these actual thought into it begins with the question of where do you start?

When you just think about it the entire thing seems simple enough, just weld together the tube like other vehicles you see, but to begin such a project you would quickly realize its not as simple as it seems.

Where do you get your dimensions from so everything fits when your done? Do you start with an existing production vehicle and just weld your tube to fit its parts?

Where do you learn how to get the frame straight, are there affordable tools and tricks to do all of this?

I'd really like to make a 5 or more year project out of putting one of these together myself, but the problem is once you get beyond the thought of doing such a thing you have to actually begun doing something and the first problem you face is trying to find out where you even begin.

[soberchargerfan]

well. i guess the first thing you need to think of is, do i want a truggy or a buggy?

then you can start there. with a truggy, you got the frame, and with a buggy, well you need to build a frame.

[Dirty Harry]

Most guys these days design their chassis using software like Solidworks or Bend Tech to model how everything is going to fit before ever touching a tube. There are even some people out there like Chris from Azrockcrawler.com who sell specs with dimensions for a chassis. There actually aren't that many people on Reno4x4 that have built tube framed buggies. I'd recommend Pirate4x4.com or TheRockGods.com for more suggestions on how to build a full tube crawler.

[Ampdraw]

Most guys these days design their chassis using software like Solidworks or Bend Tech to model how everything is going to fit before ever touching a tube. There are even some people out there like Chris from Azrockcrawler.com who sell specs with dimensions for a chassis. There actually aren't that many people on Reno4x4 that have built tube framed buggies. I'd recommend Pirate4x4.com or TheRockGods.com for more suggestions on how to build a full tube crawler.

Thanks, that was exactly the kind of info I was looking for, a place to start. I did a quick look over of all the info you just gave me and its golden!

[Ampdraw]

well. i guess the first thing you need to think of is, do i want a truggy or a buggy?

then you can start there. with a truggy, you got the frame, and with a buggy, well you need to build a frame.

I want to build the frame and make a long term project out of it so I can hit it as I can afford, be able to do it myself, and just make it a major father son project we can work on in our spare time. I think Dirty Harry hit me with the kind of links I was looking for, particularly with the links to an already designed plan I can work from. The software he suggested is also very affordable, shaking my fears I'd need some kind of $10,000 CAD program just to begin with or even make the dream possible.

[WILLD420]

If you want the pleasure of building your own chassis, then please do so. I am torn on my future plans.

I can buy a chassis for about $1500-1800. I really think that will save me a lot of time and frustration, but it's a generic platform and I would hate to buy one, then have to cut it up to make it work.

I think you are definitely going the right direction. Harry and I don't always agree but he's got his stuff together when he talks rigs and off roading. I would definitely utilize his knowledge, as well as that of Dr. Smash in Carson City.

The best way to start any project is to treat it like a house or garage. Visualize the end product and it's use, then reverse engineer it till you get back to the nuts and bolts. Ie. No need to run a Rockwell axle if you plan on making a long travel desert racer out of it. No need to run a Dana 44 if you are planning on running 42" tires with doubler gears.

[Travman]

like harry said bend tech pro is a good program. im starting my own truggy* project here soon as a family project. I know a couple people that have taken something like a blazer chassis (for example) and then tube out around that. that way they already have axle placement. and points of structure. and the engine is good to go cause it didnt have to be transplanted in and then wired up and etc.etc. and that is soething like a hybrid truggy because you dont have the cab of a vehicle you have a buggy enclosure.

There's alot to this if your going to go the buggy route you litterally start from scratch. and will have to fab a lot so get friendly with gringers, cutting wheels, torches, and welders, big hammers a vice, a bender etc.

mine will be started with boxed steel. and i will be using 1'' and 5/8's DOM Tube for everything - which is another thing. Dom and schedule 40 once you start researching tube i will gaurantee you will start seeing arguements for schedule 40 being perfectly fine for rock crawlers. to a point it is. I have SCH40 all over my bronco( my front bumper my rock sliders my rear bumper and tire carrier. but will it be used for my roll cage NO. the fact is the wall has inconsistencies and could have a weak point in a structural/important area and you would not even know it until it would be to late. i am for SCH 40 just not for points of safety.

now when you start designing your cage you need to figure out a lot.
how many seats do you want. what suspension you will use. what engine will you use if your gonna put a 454 0r 460 or even bigger that will take play. front or rear engine? Rockapes (he's on here and the owner of TRG.com) single seat buggy is rear engine. what wheel base you want. what axles you will use. if you plan on rockwells plan on a heavy duty suspension. a single rockwell weighs 700+ lbs depending whats on it. they weigh in just under 700 lbs with the drum brakes off. this all takes play for shock hoops or mounting brackets for your linked suspension. points where you can put your coils and so on you'll start learning the more you start doing.

i my self will be using 2 chevy/dodge lp 60 steering axles for 4 wheel steer.
and the plan for the finished produst is putting my extra cab dakota on the frame I build.

any more questions post em up

[Dirty Harry]

The best way to start any project is to treat it like a house or garage. Visualize the end product and it's use, then reverse engineer it till you get back to the nuts and bolts. Ie. No need to run a Rockwell axle if you plan on making a long travel desert racer out of it. No need to run a Dana 44 if you are planning on running 42" tires with doubler gears.

I agree completely. I would recommend having a clear vision of what you want the final product to be and getting the ENTIRE drivetrain before you touch a single piece of tube, that way you can build around it. Personally I have a bad habit of starting a project (particularly one as long and involved as this) and changing my mind in the middle and having to do a lot of things over and spend a lot of money twice.

[ZIPGRAVER]

Why not talk to our own Leroy here. I don't know what his screen name is but I know he built this cralwer tube chassis all by his lonesome....and it's NICE!

[BurbanHunter]

Why not talk to our own Leroy here. I don't know what his screen name is but I know he built this cralwer tube chassis all by his lonesome....and it's NICE!

I wondered if he was on here, his gf works with my gf. I've seen pics of his rig, really nice!

[Dirty Harry]

His user name is skipped_link, and there is a whole build thread on Pirate for his awesome buggy.

http://www.pirate4x4.com/forum/showthread.php?t=615419

[xjmoser]

Personally I have a bad habit of starting a project (particularly one as long and involved as this) and changing my mind in the middle and having to do a lot of things over and spend a lot of money twice.

This has happened to mine more than a couple times.

[rundovr]

anyone want a toyota truck frame I have one I'll give you. it is an extra cab so you could cut it down and make a good trugy. Let me know

[Ampdraw]

Just spent the entire evening reading front to back of that build thread. Wow, that thing is an insane unleashed beast!

Just low and slow rock crawling is all I had in mind, nothing even near that insane.

Just thinking Dana 44's with rear steer, probably a 4 cyl toyota motor, or the simplest 4 cyl I can find with good after market availability. Thinking I'd like it to be a 3 seater, either 2 in front and one in back, or maybe 1 in front center and 2 in back slightly angled outward (not full sideways) so the rear seats aren't just direct forward facing to save space and still give some leg room. Small and light would be a primary goal. Front or rear engine would depend on what I decided to do about the seating arraignment.

I'm not a master fabricator by any means and no direct access to a CNC so most of what I use would be adapted around off the shelf parts to limit having to farm out too much CNC work.

Does look like the pirate4X4 site is a good place to begin doing a lot of reading so I can get as much of it planned out as possible. Seeing what other people have done offers idea's you just wouldn't have thought of on your own. Also nice to see it go from start to finish like his build thread.

[rok-jeep]

Just spent the entire evening reading front to back of that build thread. Wow, that thing is an insane unleashed beast!

Just low and slow rock crawling is all I had in mind, nothing even near that insane.

Just thinking Dana 44's with rear steer, probably a 4 cyl toyota motor, or the simplest 4 cyl I can find with good after market availability. Thinking I'd like it to be a 3 seater, either 2 in front and one in back, or maybe 1 in front center and 2 in back slightly angled outward (not full sideways) so the rear seats aren't just direct forward facing to save space and still give some leg room. Small and light would be a primary goal. Front or rear engine would depend on what I decided to do about the seating arraignment.

I'm not a master fabricator by any means and no direct access to a CNC so most of what I use would be adapted around off the shelf parts to limit having to farm out too much CNC work.

Does look like the pirate4X4 site is a good place to begin doing a lot of reading so I can get as much of it planned out as possible. Seeing what other people have done offers idea's you just wouldn't have thought of on your own. Also nice to see it go from start to finish like his build thread.

If you are planning on a tire bigger then say a 35-37 I would stay away from the D44's. Can they be built...yes. Can they last.....yes depending on driving style. Would I put the $$$ into a rear steer D44.....no. Its been done before and is pricey but not very cost effective. You'll need chromo's and CTM's or Longfield joints for sure. Even with the Toy 4cyl. there is alot of torque when put through a doubled t-case with low gears. But that is just my .02. I would rather put the $$$ toward building 60's.

[Ampdraw]

I'm certainly open to anything at this point, just no plan to go with something as massive as those Rockwell's off the front end loader like Leroy did. 37's were what I had in mind, I like the balance of having some clearance yet without being too high up in the air and top heavy. My thoughts on the 44 was based on this for a little more clearance under it than the 60. I don't beat stuff up too bad, hell I've been running 35's on a d30 for 5 years now without breaking anything. Then again, I'd want to take this through stuff I wouldn't even consider doing in my current MJ, so strength should take a little priority over desired clearance advantages.

[rok-jeep]

I'm certainly open to anything at this point, just no plan to go with something as massive as those Rockwell's off the front end loader like Leroy did. 37's were what I had in mind, I like the balance of having some clearance yet without being too high up in the air and top heavy. My thoughts on the 44 was based on this for a little more clearance under it than the 60. I don't beat stuff up too bad, hell I've been running 35's on a d30 for 5 years now without breaking anything. Then again, I'd want to take this through stuff I wouldn't even consider doing in my current MJ, so strength should take a little priority over desired clearance advantages.

If I remember right a Dynatrac ProRock 60 has the same if not better clearance then a D44. But that is big $$$

[L.D.]

this too is a home built rig on a toyota frame

[wixjp]

If I were you Id start going on some runs with some guys with buggies. Take a close look at the detail and the work that goes into them. Pick their brains. For the most part they dont really post on this site See what some of these buggies are capable of doing and how they should be built to handle the abuse you will put it through. They are not just go-carts with big motors and tires. It takes a whole lot of time, MONEY and planing to do it right. Basically you're engineering a car that if not done right could very easily hurt/kill you. And if your married you better have a understanding wife.

[Ampdraw]

Yea, we've been going to all the rock crawl comps for a couple years now, I have gigs of images on the hard drive of various up close details from a lot of different rides. Its been something most people probably always think they would like to do, few ever actually do.

I'm 42, so I'm a little older now, have a little more money than I did when I was only 30, and not getting any younger. I'd be 3 years out before even sparking my first weld on such a project, just wondering where to even begin to better help me decide what I need to begin buying. My job has had me moving back and forth between Reno and Vegas for the past few years so I've been doing the apartment thing. Things have settled down and I've been out looking at houses the past few weeks so I'll finally have a garage again here soon.

Figured I'd start by filling it up with the basics, axles, tranny, transfer case and motor. My thinking was I'd start with these basic mechanical parts, kind of set them out and try to build up around what I end up with. That is what raised the question first in my mind of if this is actually the best way to go about just beginning from my clean slate.

L.D.
Nice looking ride, hard to tell in the pick, but is that the actual original Toyota frame under that, or did you just gut the Toyota and use the dimensions and misc parts from it to build up your own frame?

[ZIPGRAVER]

His user name is skipped_link, and there is a whole build thread on Pirate for his awesome buggy.

http://www.pirate4x4.com/forum/showthread.php?t=615419

He's also one hell of a nice guy and very friendly and probably really helpful. I saw him jump that rig at RFR. My little buddy asked him if he could sit up in it and he said "Hell yeah!"

[L.D.]

L.D.
Nice looking ride, hard to tell in the pick, but is that the actual original Toyota frame under that, or did you just gut the Toyota and use the dimensions and misc parts from it to build up your own frame?[/QUOTE]

it is a full '79 toyota frame with a formula toy copy tube chassy set on top. we made the chassy first, then started adding to it. the frame is from my p/u. looks alot better now with skin on it.

[skipped_link]

Ampdraw, Thanks for the props, I'm gald you enjoyed the thread on pirate, I actually have very little advise for you, since each person takes on a project in different ways,
You asked where a person starts, well in my opinion you've already started. The first spark, or thought is really the beginning, you've obviously had a thought of building something for a little while since you've been taking pics of rigs & details, and probably already have a good collection of images that caught your eye,

As posted above, having most all of the big parts is a good idea, nothing burns out a project faster that having to wait to save a couple thousand dollars for those new coilovers, or tires & beadlocks, ect.
Plus when everything is there some good quality time with a tape measure will go a long way,

You were loking at a 4 or 5 year window. Collecting parts for 3 or 4 years & usethat time for thought, & planning, then the last year will be much more fun while building the machine & knowing what direction you are going, it will go smoother too.

I built the rig above in less than a year, Now having a good handle on fabrication, plus experience building a few rigs helped get it done quick, but what really made the project move along was the fact I'd spent at least that much time planning the rig, & almost all of my parts were right there in the shop, (or the spare bedroom). Thinking back the only thing I had to stop & wait a couple paychecks for was the aftermarket fuel injection, (which I wound up no using in the end)

Which brings up another good point, also posted above, get out & get some rides in with other rigs you like the looks of, or something similar to what you would like in your finished ride,
For example, I started with a 501 cubic inch aluminum headed big block ford, I used it cause it was kind of just sitting around in the shop, thats a good reason to use it, but one trip out with it I found that there was no reason for that much power in a rig I mostly want to just go wheeling in, a good running EFI 5.8 would have sufficed just fine. Had I rode in a similar rig, weather it be high power, or fairly moderate I would have known that & could have directed less attention to power, & more to just getting the project done,
If you can catch a ride in a rig similar to what you want you might find that the 4 cyl might not be ehough,
Or even a rig similar to what you want, only v8 powered, you might like it, or it might be more power then you want in a rig,
In a big project, there is more to accumulate than parts. Ideas, & thought go a long ways, & they can be accumulated too.

And now to answer your origonal question,
When it comes time to go for it & get to building, everyone does things differently, My build up on pirate is pretty much in the exact order I built the machine, The whole thing started with the diffs, wheels & tires were the next thing purchased, I used these parts to get an idea of how much room I had for a frame while turning lock to lock, I also used a dummy/mach up engine, tranny & t-case, to figure out placement, ride hight, & wheel base,
The main frame was built using the data I had collected from only a few parts, then I just started building from there,

Sorry if I rambled on a bit much in this post, those are the first things that popped into my mind when I read your origonal post, If you have specific questions about anything I would be more than happy to help if possible,

Also if you ever want to go wheeling and get a feel for different rigs your more than welcome to come along with my friends & myself, there are rigs in our group that range from the buggy posted above, to a nearly stock toyota that has a bit of a loose nut behind the wheel, included are a couple truggies, & jeeps,
The invitation is open, & we'll be going out a fair bit this fall,

[WILLD420]

I have some experience in vehicle dynamics so I'll give you a couple quick tips.

Remember Newtons laws when building it. Ie, velocity is proportional to mass/thrust.

When thinking about where to put the driver and passengers, remember that the speed changes are what hurts you in a crash. The closer you are to the center of the vehicle, the slower you accelerate/decelerate in a crash. If you are sitting on the front bumper when it goes over backward, you get a heck of a ride...

Think long and hard about roll angle, center of gravity, roll center etc. (I may have some of these terms mixed up, it's been awhile since I read my books.)

Race cars and passenger cars are designed with crush to absorb energy. I can't think of any reason this shouldn't be applied to some portions of a rock buggy.

Before you finish a weld, make sure you can access the important stuff behind/under/over it. My friend has a very very nice long travel rail that requires half the rig to be stripped to change the battery. Guess what he gets to do every other year....

Cast iron case doublers are heavy. Nuff said.

An auto tranny will always be easier to drive in technical stuff and your new drivers will appreciate that a lot.

Think steering linkage is a PITA to get right? Go for a ride in one that has it all messed up...

The difference between 25 mph over whoops, and 75 mph over the same terrain can cost you a cool 50 grand if not more.

Leak proof gas cans and fuel tanks, Aren't.

Exhaust is hot. So is oil after a few hours of hard running..

You will never have to change a tire on a flat level, hard packed surface.

[Dnmeistr]

From what you described and from your experience you would be better off building a formula toy, somewhat like LD built. Pretty sure you can buy the tube chassis and just use a Toy frame and drivetrain. Those Formula Toys do very well in rock crawling with leaf springs and some even compete in KOH. Another option and possibly better it to buy a built buggy, there are some very good deals on Pirate for under 16K.