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total cage weight?

NA, time to cage. Chump sprints and local series. Specs are 1.5X.095 DOM or 1.5X.120 ERW. Nascar door bars/etc.

Getting wildly different weight numbers from several, well known, weld-in cage suppliers. Starting at 100lbs and maxing out at almost 160lbs. This isn't making sense to me, even with the weight difference between the two different tubing sizes, which I calculated to be around 15lbs for the approx. 70 linear feet of tubing for the typical NA miata cage.

Need independently weighed/confirmed #'s for the total weight of your cages, as installed. Even if you built it yourself, if it's been weighed/you know tubing size/type and it passed tech for Chump/NASA,SuperMiata/etc. I'm interested. Tks.

The tube will weigh about 100lbs. Add your plates, plinth boxes, harness tabs, gussets, and seat bracket, and suddenly like 130 starts to sound realistic.

DOM is about 1.5lbs per foot.

Quote:

The MiataCage.com custom roll cage kit consists of roughly 69 feet and 24 pieces of 1 ½ by .095 DOM Tubing. The kit weighs roughly 100 lbs once installed in the vehicle and when installed properly is approved for SCCA, NASA, ICSCC and other sanctioning bodies competition.

And it's pretty close but while doing the cage you also lose some weights by trimming, cutting and so on so I don't have A/B on scale for you..

https://www.miataturbo.net/attachmen...ine=1456179148

this is the cage i'm currently building. it's not 100% finished. but it will come out around 112 lbs. 1.5"x.120 for the main bars. 1.5"x.08 for the optional bars.

Is that Bend Tech Pro?

I'm kinda on the fence about the $300 price tag for 1 time use.

Quote:

Originally Posted by Ben (Post 1310123)

Is that Bend Tech Pro?

I'm kinda on the fence about the $300 price tag for 1 time use.

it is, and it's amazing. this is my first experience bending tubes. literally no experience and i haven't had a scrap tube yet. highly recommend it. i bought it off of JD2's web sight with a notcher. they had it on sale for 280.

https://www.miataturbo.net/attachmen...ine=1456259463

this is the halo bar i bent. it fits perfectly, and gave me good amounts of headroom.

I wish we were allowed that many bends in ours!

They wouldn't certify that here....

Quote:

Originally Posted by mx5-kiwi (Post 1310461)

I wish we were allowed that many bends in ours!

They wouldn't certify that here....

my FB blew up too.this is the halo bar. in nasa there are no "max bends" in a halo type bar. in the car my head has a good 6" distance from it. the bends in the photo look like they are bent inward towards my head, but actually they are bent vertically(see the bend tech photo). so it will provide strength if the shiny side went down.

Quote:

Originally Posted by NASA CCR

15.6.9 Halo Hoop (Option 2)
A “halo bar” extends from the main hoop (in a forward direction) following the roof line to the windshield then
following along the top of the windshield, then following the roof line back to the main hoop, thus creating a
“halo” over the driver’s head. A “halo” bar should be constructed of one (1) continuous piece of tubing. One (1)
down tube following the “A” pillar should support the “halo” on each side of the car. The down tubes shall
incorporate no more than two (2) bends each.

many people mistook the allowed bends the forward halo style of bar. that of course has a max of 4 bends.

Quote:

15.6.8 Forward Hoops (Option 1)
The forward hoops should extend from the main hoop (in a forward direction) to the floor by following the roof
and the “A” pillar of the car. There should be a bar connecting the two (2) forward hoops at the top of the
windshield mounted as close to the roof as possible without violating CCR Section #15.6.20 Inspection. The
44
forward hoops should incorporate no more than four bends each. Optionally a “15.6.9 Halo Hoop (Option 2)” or
“15.6.10 Front Hoop (Option 3)” construction may also be acceptable.

Quote:

Originally Posted by joyrider (Post 1310048)

And it's pretty close but while doing the cage you also lose some weights by trimming, cutting and so on so I don't have A/B on scale for you..

Somewhere on the internet I read that its basically a net zero weight change on the cage if you fully gut the doors, like beyond what specmiata normally does. :jerkit:

ERW isn't NASA legal so don't use that.