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View Full Version : frame stiffeners...anybody heard of these


pyrothugg
September 30th, 2009, 05:05
was searching for a parts catalog and came upon something much more interesting anybody ever heard of or know anything about these frame stiffys are they better then the TNT and the TMR stiffys.

anyway heres the site
http://www.rocdogfab.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=25&category_id=9&option=com_virtuemart&Itemid=59

JeepAddict85
September 30th, 2009, 05:07
they look pretty nice, and they extend fully to the front/rear. Probably a bit lighter with all those holes.

pyrothugg
September 30th, 2009, 13:41
yea im considering em

Begster
September 30th, 2009, 13:50
http://www.naxja.org/forum/showthread.php?t=942465

I saw another thread about these recently as well.

Hammered
September 30th, 2009, 13:50
just buy a sheet of plate and some big sheets of paper and make your own templates... cut your own - Or check around at plasma / laser cutting places you may be able to have the same basic thing made cheaper, with your templates.

worth a shot for over $200

asp
September 30th, 2009, 14:56
they look pretty nice, and they extend fully to the front/rear. Probably a bit lighter with all those holes.

i'm trying not to laugh. the holes are for more welding areas, not to decrease weight. since the majority of the stiffness comes from the outside of the stiffener, taking a hole out of the middle (think like you're taking a hole out of the rib of an i-beam). moment of inertia is proportional to the height^3, so a little out of the middle (which will have a small h) won't matter much. due to the fact that the sheet metal of the unibody is so thin, only a few weld spots would not be adequate for stiffness-matching of the plating to the unibody. once again, think stress distribution. what the hell do you expect. i'm an engineer.

but for real, keep tech in tech. this doesn't belong in this forum.

pyrothugg
September 30th, 2009, 16:33
well that is definately something to consider i mean being an engineer you would definatly know more about force tolerances and stuff than me its defenatly something to think about thanks for your input

JeepAddict85
September 30th, 2009, 16:42
i'm trying not to laugh. the holes are for more welding areas, not to decrease weight. since the majority of the stiffness comes from the outside of the stiffener, taking a hole out of the middle (think like you're taking a hole out of the rib of an i-beam). moment of inertia is proportional to the height^3, so a little out of the middle (which will have a small h) won't matter much. due to the fact that the sheet metal of the unibody is so thin, only a few weld spots would not be adequate for stiffness-matching of the plating to the unibody. once again, think stress distribution. what the hell do you expect. i'm an engineer.

but for real, keep tech in tech. this doesn't belong in this forum.


yes i know the holes are for more welding, but they are quite a bit larger than the regular ones you see for plug welding. since they are that much larger, it doesnt seem like it would be necessary to completely fill in the circles with weld. so...less material used...less weight...same amount (relatively speaking) of welds. am i correct in my reasoning Mr engineer?

pyrothugg
September 30th, 2009, 16:44
lol

Hammered
September 30th, 2009, 17:22
I'm just thinking i'd weld the full circle...and sure it might be a lil lighter but not by much. I'd just do like 10 guage sheet and make my own if it were gonna just be flat small sections like that... I think the bent full length ones seem like a stronger design

asp
September 30th, 2009, 17:43
yes i know the holes are for more welding, but they are quite a bit larger than the regular ones you see for plug welding. since they are that much larger, it doesnt seem like it would be necessary to completely fill in the circles with weld. so...less material used...less weight...same amount (relatively speaking) of welds. am i correct in my reasoning Mr engineer?

not really. you wouldn't want to plug weld them. plug welds are typically used when material thickness is closer to the hole size (like a 1/2" hole in 1/4" plate). these are 10g i think (so figure about .135" thick) and the holes in these look to be around 2" or more. pooping weld to fill a circle will not increase the weld area properly and it would probably distort the crap out of the unibody. i'd do stitch welds around the perimeter of the circle, just like around the outside.

JeepAddict85
October 1st, 2009, 07:23
not really. you wouldn't want to plug weld them. plug welds are typically used when material thickness is closer to the hole size (like a 1/2" hole in 1/4" plate). these are 10g i think (so figure about .135" thick) and the holes in these look to be around 2" or more. pooping weld to fill a circle will not increase the weld area properly and it would probably distort the crap out of the unibody. i'd do stitch welds around the perimeter of the circle, just like around the outside.

isnt that what i just said?

'since they are that much larger, it doesnt seem like it would be necessary to completely fill in the circles with weld'

kastein
October 1st, 2009, 10:02
nope, what you said was a plug weld...

what he's describing (I believe) is a rosette weld, or just a lap weld all the way around each hole. You're using the wrong terminology, but then again I probably am too.

JeepAddict85
October 1st, 2009, 12:17
nope, what you said was a plug weld...

what he's describing (I believe) is a rosette weld, or just a lap weld all the way around each hole. You're using the wrong terminology, but then again I probably am too.

i said they are similar to plug welds but are much larger.

on another note...is that what a rosette weld is? I figured for the larger holes you would just weld around the perim of the circle, or do a few stitches inside of each.

pyrothugg
October 1st, 2009, 13:21
wow okay im out of my league i cnt even weld i have to have my uncle do all my welding he said about stiching it

asp
October 1st, 2009, 14:41
rosette welds and plug welds are the same thing.

JeepAddict85
October 1st, 2009, 18:49
rosette welds and plug welds are the same thing.

good to know...thanks

Hammered
October 1st, 2009, 20:16
Bubble gum welds and Booger welds are the same thing.

:D

Begster
October 1st, 2009, 21:21
i said they are similar to plug welds but are much larger.

on another note...is that what a rosette weld is? I figured for the larger holes you would just weld around the perim of the circle, or do a few stitches inside of each.

While I understand that you both are talking about the same thing, I'll say this.

This wouldn't really be similar to a plug weld. You can sort of think of a plug or rosette weld as a screw: you have one material overlapping the other, and want to attach those two materials to each other.

You first create a hole in the top most material, and then proceed to start at the bottom material, and weld the two pieces together, filling in or "plugging" the hole as you go. A plug weld is always done with relatively small sized holes.

This is why Anthony started talking about why you shouldn't plug weld a hole that big. By definition, if you were to plug weld it, you would have to fill that entire hole with weld, which would do nothing for you.
Instead, you would do as you both stated, stitch weld around the perimeter of the hole. This would then just be a stitch weld, regardless of the fact that you are stitch welding a hole.

Hammered
October 3rd, 2009, 17:02
And there you have it.

cmelo
October 3rd, 2009, 20:22
I would bolt them on

Hammered
October 3rd, 2009, 20:31
I have some double sided tape for the hard to reach areas.

cmelo
October 3rd, 2009, 21:35
The tensile strength of the double sided tape may not be sufficient for use on the unibody. Although, I believe with proper pre and post heating it would be adequate.

Hammered
October 3rd, 2009, 21:36
Good point, subscribed

pyrothugg
October 4th, 2009, 08:00
ive heard good things about the tnt and the tmr ones since i dont have the ability to make my own at this point i may look into them the tnts cover the underside and the tmrs cover the outside

Hammered
October 4th, 2009, 09:08
I'm sure youve done some searching on here for guys that have done this... theres quite a few threads / install writeups on dis sit.

XJ Beater
October 4th, 2009, 09:19
did anyone read the damn description on their website? here ya go---Circular openings provide weight reduction as well as welding points for secure mounting.

asp
October 4th, 2009, 15:19
ive heard good things about the tnt and the tmr ones since i dont have the ability to make my own at this point i may look into them the tnts cover the underside and the tmrs cover the outside

if you can't make them i'd reconsider trying to install them in the first place.

pyrothugg
October 4th, 2009, 16:10
i just cant make them because i dont currently have the tools at the ready my uncle has a welder he said hed weld em for me he welds as a profession so installing them wont be a problem