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Don't know why folks still second guess the strength of aluminum. I know an extensive amount of folks running AL as bumpers, rockers and skids who continually test them on 7 to 10 rated trails and the come out unscathed. About the only advantage steel has over AL is paint / powder coat adheres better and a slight lower cost... That 's it
 

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I have never once said, "I almost made that obstacle, but my aluminum skid kept me from sliding."
Yeah, yeah Steve :p. Aluminum will gouge easier on hard rocks than steel. Craig at Rockworx (Montrose) told me he would use some sort plastic (maybe HDPE?) fixed to an aluminum skid.

Be that as it may, I wouldn't have a problem with an aluminum skid on my Rubi made from 3/8" plate.
 

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I have never once said, "I almost made that obstacle, but my aluminum skid kept me from sliding."
Sorry, I can't refrain from saying.........
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.X2!!!!!
 

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Yeah, yeah Steve :p. Aluminum will gouge easier on hard rocks than steel. Craig at Rockworx (Montrose) told me he would use some sort plastic (maybe HDPE?) fixed to an aluminum skid.

Be that as it may, I wouldn't have a problem with an aluminum skid on my Rubi made from 3/8" plate.
That is a leap in counter intuitiveness, eh? Aluminum is too soft so lets put something 50 times softer over it so it will slide better? I hear, I see it, but I don't buy it.

As far as aluminum sliding easier than steel over sharp rocks, that is too subjective to define that easily.



See all those marks on that skid plate? Notice how they go from front to back? If one was to operate from the position that aluminum gouges and hangs you up, it would seem that it would be very easy to examine a skid such as that one and make a very definitive argument based on the number of marks that stop a short distance in with a resultant gouge at the end of each that stopped forward or rearward progress.

There is a reason you don't see them because for all of those marks, not once in hundreds of trails in JV has that ever happened.

I did get hung up once on my gas tank skid, but my wife was spotting me and happened to get me into a spot that as soon as both rear wheels found nothing but air for traction, a big rock popped up under the rear bumper.



When it comes to designing around stuff that will slide over rocks, it is all about the radius. If you take a bent steel slider with no tube on it, the radius is very small at the lower corner and rocks will dig in and stop progress. If you weld a 3/4 round section of 2" 1/4" wall tube to that same edge, it will slide like nobody's business and never hang you up.

There is also a reason I won't ever design aluminum for that application and that is because the radius is too small even for a larger diameter tube.

You have to pick material and use it where it works or put another way, don't use material that won't work for certain things.

If you consider that the radius of a belly skid is nearly infinite, the likelihood of hanging up on it is dramatically decreased.
 

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Blaine - looks like your skid has taken a lot of abuse. I need to get together with you after the holidays to get some stuff on order.
When I built and installed it, I was told all the same things in the negative that everyone repeats today. It won't slide, it will bend, it will gouge, and it won't work. I was working on ambulances and they have a lot of aluminum on them so I started doing my research which backed up my experience working with the stuff.

That skid in the picture is actually 5/16" and not 3/8". The mistake I made in picking that thickness which is more than plenty when mounted flat is that for some reason, it costs more per pound than 3/8" likely due to less demand.

I built a new one last year purely for aesthetics and to improve the design. I blew up my shop press bending the front part of the engine skid, but it's all fixed and better now. I lay the front part of the skid across the press bed with no supports other than the bed rails and mash it with a piece of solid bar stock 2" in diameter to roll the edge. The skid is 13" wide and it split the bed apart and sent chunks flying across the driveway. The welds failed so now it is through bolted.

It takes 20 tons to air bend 13" width in 3/8" with a 50% smaller top punch than lower die opening width.

Let me know when you are ready and I'll do my best to get you pointed in the right direction.
 

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Yeah, yeah Steve :p. Aluminum will gouge easier on hard rocks than steel. Craig at Rockworx (Montrose) told me he would use some sort plastic (maybe HDPE?) fixed to an aluminum skid.

Be that as it may, I wouldn't have a problem with an aluminum skid on my Rubi made from 3/8" plate.
Funny you mention plastic John, because it popped into my head also. Seen a few competition rigs using plastic under their rigs.
 

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That is a leap in counter intuitiveness, eh? Aluminum is too soft so lets put something 50 times softer over it so it will slide better? I hear, I see it, but I don't buy it.

As far as aluminum sliding easier than steel over sharp rocks, that is too subjective to define that easily.



See all those marks on that skid plate? Notice how they go from front to back? If one was to operate from the position that aluminum gouges and hangs you up, it would seem that it would be very easy to examine a skid such as that one and make a very definitive argument based on the number of marks that stop a short distance in with a resultant gouge at the end of each that stopped forward or rearward progress.

There is a reason you don't see them because for all of those marks, not once in hundreds of trails in JV has that ever happened.

I did get hung up once on my gas tank skid, but my wife was spotting me and happened to get me into a spot that as soon as both rear wheels found nothing but air for traction, a big rock popped up under the rear bumper.



When it comes to designing around stuff that will slide over rocks, it is all about the radius. If you take a bent steel slider with no tube on it, the radius is very small at the lower corner and rocks will dig in and stop progress. If you weld a 3/4 round section of 2" 1/4" wall tube to that same edge, it will slide like nobody's business and never hang you up.

There is also a reason I won't ever design aluminum for that application and that is because the radius is too small even for a larger diameter tube.

You have to pick material and use it where it works or put another way, don't use material that won't work for certain things.

If you consider that the radius of a belly skid is nearly infinite, the likelihood of hanging up on it is dramatically decreased.

Are you blaming your wife :grin:
 

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I think what everyone is missing about aluminum is, What type of aluminum!
I wheel with friends that have aluminum boatsides on ther JK's mfg. by other companies that I will not say, and they bend and gouge and leave aluminum on the rocks... I have been running the Original Savvy UA for a couple of years now and looks close to mrblaines and it has not bent or gouged or stopped sliding. My old custom 1/4" steel skid(65lbs heavier) that hung down over 3" more than my Savvy UA had more gouges and dents than my aluminum. BTW, 3" of belly clearance = 6" taller tire. 35"-41" tire. Wouldn't change from good aluminum for anything.
 

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Yeah, yeah Steve :p. Aluminum will gouge easier on hard rocks than steel. Craig at Rockworx (Montrose) told me he would use some sort plastic (maybe HDPE?) fixed to an aluminum skid.

Be that as it may, I wouldn't have a problem with an aluminum skid on my Rubi made from 3/8" plate.

Most folks I've seen use UHMW plastic (Ultra High Molecular Weight) to help slip over rocks
 

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Old thread revival- anyone move on from the Nth TT to the Savvy UA? Does the Savvy skid/crossmember sit higher than the Nth?

I have the Nth (auto and 241) now, and I'm ready to move on to the Savvy. I'm curious if I am going to need additional tub massaging. I do have a Currie 1 inch BL.
 
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