mgmetalworks
Explorer
80/20 has the deflection calculations on their website.
UJOR Build Thread
- Thread starter ujoint
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Bikersmurf
Expedition Leader
X2
If you were nearby, I'd bring mine in to get it coated... I can only dream though.:bowdown:
ujoint
Supporting Sponsor
1st off it has to be the correct rig. Not too old or dirty/nasty underneath so we can get it clean inside the shop while its torn down. I'll only do it if we can make it look the way I want. After cleaning & rust removal we use a spray bedliner from a can. Nice finish, holds up well. We have done some rigs with POR15 if there is a rust issue.
While we're tossing questions at Chris on his day off, I've got a couple concerning roof racks. If my eye-ball estimator is properly calibrated it looks like you're using 1x2 for your rack profiles, is that correct? Whatever being the case, how much deflection under load do you see on the across the width of the roof?
I'm looking to do something on my Ambo but I'm also looking at about an 84" span across there. I'm going to custom make the side...panels I guess you'd call them, but I want to use the 80/20 profiles for the cross bars. I'm hoping 1x2 will get it done so I can keep overall height down. It'll have some sort of decking to it so I can toss a chair up there at events and lord it up over the ground dwellers.
I suppose I could put some kind of "foot" mid away on the cross bars to lend support under load, but if I can avoid that I'd rather. It's not like I intend to toss tons of load up there, but it's quite a span.
MG always makes mathematical sense of things
We do use the 1x2, its the 10 series from them. Originally had the side bars laying down but there was way too much deflection. Standing up there isn't on a 5' wide rack. I would definitely check their website and do the math.
ujoint
Supporting Sponsor
Its a big job, and yours would be a super big job!
naterry
13 Cheeseburgers
Bada-bing:
https://8020.net/deflection-calculator
Great tool, and much easier than calculating the modulus' based on their profiles!
patoz
Expedition Leader
Thanks for this!
Tom, when you get it all figured out be sure to post it, because I need the same info! :agree:
I figured it 2 ways.
First way:
1020 profile (1"x2") 84" long, fastened at each end with 250# centered load and 2020 profile the same way.
The 1020 had .250 of deflection in the center and the 2020 had a bit over .100.
If you lay the 1020 on its long side deflection goes up to just shy of 1.00".
I didn't price it out, but my first inclination is to go with the 1020 with the thought that if it's a 2-1 on pricing I can buy twice as many and halve the spacing. I could certainly live with the .250 deflection because odds are it would never see that much load centered anyway, and that's on just one crossbeam.
Even if it isn't 2-1 pricing I can still buy more for the same cost as the 2020.
Those deflection numbers aren't exact because I'm going off memory from last night, but they're within a few thousandths so close enough for government work.
I planned on leaving a 1" gap between the roof and bottom of the crossbars so I'll have plenty of clearance.
ujoint
Supporting Sponsor
It came out of CO. Has already had a ton of engine work done here by a buddy of mine, now its time for suspension.
Bikersmurf
Expedition Leader
I know, I sandblasted and put 5 coats of paint on a newer frame for an FJ40... I'm not planning to go that far again.
So far, I've been doing the harder part while things are apart. Spring buckets, shackle mounts, and suspension... Major PITA to do while on a creeper or crawling in the ground. The PO must of thought it was a 4x4... Every time I go under it there is a pile of sand/dirt on the driveway.
Next up will be painting the spare fuel tank, dropping the original, painting the inside of the frame, and installing the new tank... Wheels first though.
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