TheSamba.com :: View topic - time to finish the a-armed baja

Wed Sep 03, 2008 11:07 am

ok well im back workin on the a-arm baja.. had to take a break when the baby was born... now my son is 2 1/2 and i get more time in the garage.. so i got all the measurments for my arms and cut them out of plastic to get a feel for how the fitment will be and so far so good... i like the upper arm but im not to crazy about the lower might have to make some changes... but the suspension is pullin 24" of wheel travel metal to metal and will be strapped at 18 or 19" the wheel track ia 80" and the wheel base is 115-120... i should have all the cut outs of metal by friday and should hopefull have a arm or 2 mounted to the center point mounts... also will be doin a custom spindle...

strapped the suspension will bump with 9" of up travel with 5* camber change at full bump and will droop 10" with 0* camber change ride height will be around 15" and caster is set to 10*

Wed Sep 03, 2008 12:40 pm

Looks like you got a good plan going.

I know this is pretty much splitting hairs but that would be a J-arm car not an A-arm.

Wed Sep 03, 2008 12:56 pm

Those mock ups actually look like the spindles a guy I knew designed for a SAE car. Electron beam welded and all.

Wed Sep 03, 2008 1:13 pm

lol you got me... ya i know it a j-arm car not a "a-arm" car but its all the same....kinda.

xirx that electron welding sounds cool! i hope i can get something mounted this weekend ive been on this car for 2 years now.. but i finally got the suspension cycleing good and clean so the fabing should go smoothly now...

anyone here know what happened to a guy on here named (everyjuangohome)? i gave him the dimension to my suspension setup just wondering how his turned out...

any way thanks for the comments ill be keeping you guys updated

Wed Sep 03, 2008 3:53 pm

I would almost think you were trying to reinvent the wheel. Why not just use what someone else has proven to work well? I say just build 'em already! You planning on running this thing in the Baja 1000 or something? OR Are you one of these guys who never has a rolling / running car but always working on one all the same? If so, big giant waste of time and money.

Wed Sep 03, 2008 4:26 pm

dude those arms would look way out of place on your car, no offense but i think you need to tone those bad boys down, they also look like they would weight a ton if they were actually made out of steel.

Thu Sep 04, 2008 8:42 am

riNR: reinvent the wheel? j-arm suspension is proven mainly on trucks that just makes putting it on a baja that much cooler haha....

and no i take a lot of time on my project im in no hurry to get it done i spent the majiorty of the time designing the suspension.. metal to metal travel is 24" strapped it should be around 19 or 18" of wheel travel.. i got the camber to a minumin only cambering in at 5* at full bump full droop has 0 camber change.... plus i didnt care to much for the beam suspension... i mean i bought all the beam parts like 4"over arm 6"beam and whatnot but when mounted i didnt like it so i solf it for dirt cheap...

and runslikeapenguin: the arms will be made out of 1 1/2"x 1/8" cromoly they shouldnt weigh to much but they will be beefey... i actually want some added weight up front since VDUBS tend to jump nose high i want to somewhat even out the weight with the motor in the rear so it should be just fine...

what you mean out of place? should it just be a normal tube suspension...boring... lol plus this was of boxing them in was much much stronger than bending tube..

Thu Sep 04, 2008 10:11 am

I always thought they did j-arms because the motor is up front and that was the only way on some of the builds to get the suspension to work as good as it does.

Thu Sep 04, 2008 11:24 am

i guess it depends on the build and what type of build but for the most part they do a j-arm so they can fit a coil over and a bypass shock..

Thu Sep 04, 2008 8:19 pm

1/8" steel is 1/8" steel, It all weighs the same. With your drawings have you added up the sq. inches to procure a weight. .3545 per sq. You may have a bit of a suprise compared to a tubular design. I know your mentally and probably financialy comitted but the same design in tubuar steel woud save a mass of weight. However, hang a big chevy on your butt and it's all good. Patience in welding those things, it's critical as the amount of heat heat saturation is large. I am assuming you will TIG those. If not I think Cold rolled will yield plenty of strength considering the design and save you some cabbage. Good luck.

Thu Sep 04, 2008 8:23 pm

Maybe you could get this guy to come by and give you a hand:
http://www.youtube.com/watch?v=u7ziwuIpnVY
He can figure anything out. Maybe you could make them out of wood and glue.

Thu Sep 04, 2008 8:58 pm

Is that a type 4 engine? or a 40 horse?

Fri Sep 05, 2008 8:10 am

ya i know these arms arnt going to be light... ive been debating about doing the upper arm out of tube or not but...... i dont know.. and yes these will be getting tig welded.. ive also cut off a lot of weight as well pretty much the whole stock front end.. and before i started the arm design i bought a 6"over beam 4"over tweed arms and all those goodies.. and all that put together spindles and all, that setup would weigh a lot as well so i figure ill be in or close to the same ball park weight... well see im pickin up the metal today at lunch

Fri Sep 05, 2008 8:45 am

oneUPfabrication wrote:
what you mean out of place? should it just be a normal tube suspension...boring... lol plus this was of boxing them in was much much stronger than bending tube..

those arms are going to look out of place because dude you don't have that developed of a chassis, you have a fully caged garage built baja like a lot of other guys, it looks like you did your research to build the best but you do not need arms that big, ive seen stuff smaller on clas8 trucks. if tubing was so weak then why have thousands of builds had them and run them successfully.
IMHO that bulk head dosent even look strong enough to take the beating your going to be dishing out onto it with those arms.

you also do realize your going to have to run like 6x6's to match your front track width.

Fri Sep 05, 2008 11:33 am

how the upper and lower mounts look now is not gonna stay... i have a bulkhead im cutting out of 4130 that will connect upper and lower pivots to make it one solid piece.. and will also tie into the shock towers and the a-pillers.. right now its about as wide as running a 8"over beam and 4" over arms.. i will be running 5x5s in the rear to make up the distance.. also the 80" track is measured from outside tire to out side tire...

im not syaing tube is weak... i just like the look of boxed arms.. and there simple to build.. and the reason the arms are so long is because there center point mounted. i could make the arms shorter is the pivot points were 1' and a half apart but shorter arms means less travel and my lowers will be mounted 3"apart..

another reason im choosing boxed arms over tubed is because they are so long... with boxed arms i can put bracing throughout the arm where tubed is just tube...

Fri Sep 05, 2008 12:10 pm

cad drawing of the bulk head

then from the top of the bulk head ill be building the shock towers so it will al be one piece from lower a-arm pivots to upper shock mounts and from the shock mounts to the a-piller.. trust me it will be plenty strong

Fri Sep 05, 2008 12:13 pm

oneUPfabrication wrote: how the upper and lower mounts look now is not gonna stay... i have a bulkhead im cutting out of 4130 that will connect upper and lower pivots to make it one solid piece.. and will also tie into the shock towers and the a-pillers.. right now its about as wide as running a 8"over beam and 4" over arms.. i will be running 5x5s in the rear to make up the distance.. also the 80" track is measured from outside tire to out side tire...

im not syaing tube is weak... i just like the look of boxed arms.. and there simple to build.. and the reason the arms are so long is because there center point mounted. i could make the arms shorter is the pivot points were 1' and a half apart but shorter arms means less travel and my lowers will be mounted 3"apart..

another reason im choosing boxed arms over tubed is because they are so long... with boxed arms i can put bracing throughout the arm where tubed is just tube...

is your cage .120 wall 4130?

and yes all you have been saying is tubing is weak.

Fri Sep 05, 2008 12:29 pm

where did i say tubing is weak??? tell me this? all i said is with the arms being so long id rather have boxed because i can put bracing throughout the entire arm where with tube its just tube and some cross bracing...

i think with the arms being so long (lower 28") with tube a weak point would be in the middle of that arm with all the levage from the shock and and a 31-32" tire.. so get over your self im boxing them

o and you never see a TT running a tubed lower arm maybe a upper arm here and there but most LT companies are making boxed upper and lowers expecially if the upper is a j-arm

Fri Sep 05, 2008 2:20 pm

oneUPfabrication wrote: where did i say tubing is weak??? tell me this? all i said is with the arms being so long id rather have boxed because i can put bracing throughout the entire arm where with tube its just tube and some cross bracing...

so get over your self im boxing them

o and you never see a TT running a tubed lower arm maybe a upper arm here and there but most LT companies are making boxed upper and lowers expecially if the upper is a j-arm

no you dont see TT running tubular arms because they weigh about 3 times as much as you do, they are about 3 times as fast as you will be, and they drive off road 3 times longer than your going to.

i know your stuck on making these and it looks like your committed, but your going to end up with a heavy front end man.

oneUPfabrication wrote: stronger than bending tube

oneUPfabrication wrote: tubed is just tube

just admit to why your making these arms, overkill or not.

oneUPfabrication wrote: i just like the look of boxed arms

oneUPfabrication wrote: j-arm suspension is proven mainly on trucks that just makes putting it on a baja that much cooler

oneUPfabrication wrote: normal tube suspension...boring

Fri Sep 05, 2008 2:41 pm

Quote:
i know your stuck on making these and it looks like your committed, but your going to end up with a heavy front end man.

ya i know i said i wanted a heaver front end to cominsate for the heaver rear end... i mean im not going to run a gas tank up front so theres a lot of weight lossed plus the stock bulk head and beam weigh 20+lbs not to mention the arms and spindles so i need to add a little weight up there so i dont launch nose high.. but dont get me wrong i do like to work with tube, if i wasnt doing the arms as long as they are id do tube i just think with all the lateral loads that the arms are going to see that the center of the arms would be a weak point. and mock ups ive done in the past just looked kinda funny with the super long tubes..and with boxed i have more of a flat surface for the bump stops to beat against