question about conrtol arm manufacturing?

rockrat · February 8th, 2007, 08:20 AM

My wife is going to make our long arms, but asked if it would be better to make them out of solid bar steel (8320) vice outta DOM? Through her shop, she can get solids a hell of lot cheaper than DOM.
She'll drill and tap the threads at each end. She wants to expand her old man's business into her 4x4 habit.
What's the census here?

pics added to page 4

Blackjackbender · February 8th, 2007, 12:14 PM

Quote:

Originally Posted by rockrat

My wife is going to make our long arms, but asked if it would be better to make them out of solid bar steel (8320) vice outta DOM? Through her shop, she can get solids a hell of lot cheaper than DOM.
She'll drill and tap the threads at each end. She wants to expand her old man's business into her 4x4 habit.
What's the census here?

It can be done and would be around the same stregth with DOM being a little stronger (1.5"x.25" wall) from what I gathered. I know DOM is about 11 a foot where solid i want to say is 4 from when I was researching this.

Could consider 2x2x1/4" as an option. With the solid you are going to have to run a threaded joint on both ends. and If you use a threaded poly joint at one end and a johnny joint at the other you are looking at about 80+ bucks for joints for a lower control arm.

One Arm Steve · February 8th, 2007, 12:24 PM

How much would one long arm weigh?? 40lbs or more??

95geo · February 8th, 2007, 02:32 PM

unless you have the steel laying there and your a cheap ass i wouldnt do solid steel ever.

1.75-2.0x.25-.5 for lowers 1.5-2.0x.12 wall for most uppers. if you want to be blingin go with 7075 solid aluminum tapped for the joints on the end.

square control arms usually look hillbilly.

Strangler · February 8th, 2007, 02:58 PM

I run solid. Have on three rigs. I think it is cheap, strong and easy to drill/tap.

Cooter21 · February 8th, 2007, 03:13 PM

Control arms a very important structural member to the suspention. All after market lift kits come with a huge disclaimer because of the potential carnage and abuse. We build ours from .120 wall DOM and tig all connections. I have never seen anyone including Aaron Brown use solid steel for suspension.

Haggar · February 8th, 2007, 03:14 PM

If the steel material is the same, solid stock will be stronger. But heavier, too.

For example, for a 3 foot link with 2" diameter (typical lower link)..

2.0" x 0.25" wall x 36" = 14 lbs

2.0" solid x 36" = 32 lbs

Solid bar is about 40% higher bending moment, per given size.

For equal strength, 2.00" x 0.25" wall = 1.75" solid bar.

1.75" solid x 36" bar = 25 lbs.

So, there's what you get.

However, as noted, thats same materials. Since DOM generally work hardens the piece, its stronger, so there's even a bigger weight discrepancy.

Aluminum is done with solid links because of two reasons: One, you need every bit of strength you can get with aluminum, and two, the type of alloy used fo rlinks is more or less unweldable, so its much easier to drill and tap.

Kawierider · February 8th, 2007, 03:38 PM

hmmm aluminum....we just found some 74(?) series stuff. nearly as strong as steel, more brittle though.

I think it was just AL and zinc....nothing else.......me want. (maybe not for LA's but it's a cool material)

Blackjackbender · February 8th, 2007, 06:03 PM

Quote:

Originally Posted by Kawierider

hmmm aluminum....we just found some 74(?) series stuff. nearly as strong as steel, more brittle though.

I think it was just AL and zinc....nothing else.......me want. (maybe not for LA's but it's a cool material)

alluminum links should be made out of 7075 i do not think 6061 or 6063 would hold up to well.

rockrat · February 9th, 2007, 04:59 PM

Quote:

Originally Posted by 95geo

unless you have the steel laying there and your a cheap ass i wouldnt do solid steel ever.

1.75-2.0x.25-.5 for lowers 1.5-2.0x.12 wall for most uppers. if you want to be blingin go with 7075 solid aluminum tapped for the joints on the end.

square control arms usually look hillbilly.

she's a machinist, in case you didn't catch on, her dad owns the shop

anyways just looking for ideas, as the machining business is tappering off.

rockrat · February 9th, 2007, 05:04 PM

she makes wheel spacers, coil spacers and is trying to get her dad to order the tooling to do axles.

JINX · February 14th, 2007, 08:24 AM

[quote=95geo;

square control arms usually look hillbilly.[/QUOTE]

You are that stupid!

JohnnyJ · February 14th, 2007, 09:08 AM

Quote:

Originally Posted by Cooter21

Control arms a very important structural member to the suspention. All after market lift kits come with a huge disclaimer because of the potential carnage and abuse. We build ours from .120 wall DOM and tig all connections. I have never seen anyone including Aaron Brown use solid steel for suspension.

Is this for jeep lower control arms? That's seems awfully thin.

95geo · February 14th, 2007, 11:19 AM

Quote:

Originally Posted by JINX

You are that stupid!

until you have an ounce of fabrication knowledge please STFU

rockrat · July 24th, 2007, 05:07 PM

used 2" x 32" soild for both lower ends as well as the rear uppers. Heavy yes, but at 120.00 for the steel, 250.00 for (4) 8" coils, 125.00 (4) 14.5" travel shocks=$425.00 for a 11" Long Arm Lift==priceless.

nosilla · July 24th, 2007, 05:56 PM

Quote:

Originally Posted by rockrat

used 2" x 32" soild for both lower ends as well as the rear uppers. Heavy yes, but at 120.00 for the steel, 250.00 for (4) 8" coils, 125.00 (4) 14.5" travel shocks=$425.00 for a 11" Long Arm Lift==priceless.

And knowing how to do Math is very priceless $495 is the total

95geo · July 24th, 2007, 08:17 PM

Quote:

Originally Posted by rockrat

used 2" x 32" soild for both lower ends as well as the rear uppers. Heavy yes, but at 120.00 for the steel, 250.00 for (4) 8" coils, 125.00 (4) 14.5" travel shocks=$425.00 for a 11" Long Arm Lift==priceless.

great! you spent more than what a dom would have cost! how strong are your link MOUNTS?

thats fantastic that you overbuilt the shit out of your lower control arms, now how about the rest of the truck?

balance and weight conservation are key

Rocky · July 24th, 2007, 09:18 PM

Quote:

Originally Posted by 95geo

great! you spent more than what a dom would have cost! how strong are your link MOUNTS?

thats fantastic that you overbuilt the shit out of your lower control arms, now how about the rest of the truck?

balance and weight conservation are key

My guess is stock POS TJ axle brackets.