Skid thickness???

Samco Fab

Well-Known Member
Posts
1,160
Reaction
392
I notice that most heavier Trophy Truck's run .188 thick aluminum skid plates, and most lighter buggies run .063 skids.

I am about to cut out the main skids for my 7200 truck, I am in between weights compared to a full size TT, and a 1600 or 10 car (I am about 4000 to 4500 lbs) I was thinking about using .125, but I am a bit fearful of denting a tube on the chassis, but then I am also fearful of heavy things so what experience do you all have??

Also, do most guys run 5052, or 6061?

Thanks for any imput!!
 

DBMETALWORX

Well-Known Member
Posts
1,552
Reaction
47
On our 10 car we run .250 skidplate under the motor and trans, and .125 floor pan full length.. And both are 6061 t6, the hard stuff.. The .063 floor is basically a throw away imo.. And .188 doesn't last that long either, under the rear of a buggy.. At least for us this is the case.
 

mpower

Well-Known Member
Posts
298
Reaction
13
.250" under all vital components including you! if you have a low ground clearence vehicle 3/8 will help out with gouging making the metal thinner, the stock mini ridgeline has 1/2" thick skids i believe. no less than 3/16" anywhere else that may see contact with the ground

i use 5052 as it tends to bend a lot further before it fractures or tears like 6061 can do with a good impact from a rock.
 

Samco Fab

Well-Known Member
Posts
1,160
Reaction
392
I do agree, thick skids are very good. We made 1/2" 6061 skids on our production H2, and we still bent those on occasion.

Production cars need the skids to help make the chassis more rigid, my chassis does not really need it as much for structure as the stock trucks.

I also notice the front bulkhead section of most of the current Trophy Trucks and class 1's do not use any skid, which suprises me, many look very venerable.

For conversation sake, has anybody done the math on using other materials such as thinner 4130, composites, titanium, cutting board plastic like the rockcrawlers, etc.. to use for a better skid material? I notice VW uses a composite skid of some sort on the Dakar Tourag.

Thanks for the feedback, I will lean twards the thicker side of things, not the best place to go wimpy!!
 

Wild bill

Well-Known Member
Posts
713
Reaction
30
.250 6000 series Aluminum under motor and trans. .125" on everything else.
 

Scott_F

Well-Known Member
Posts
1,045
Reaction
60
For conversation sake, has anybody done the math on using other materials such as thinner 4130, composites, titanium, cutting board plastic like the rockcrawlers, etc.. to use for a better skid material?
I am considering using a composite of .125 6061 on the top layer, and .250 HDPE on the bottom layer.
 

FABRICATOR

Well-Known Member
Posts
5,147
Reaction
107
"Jabroc Skid Plate Material, 6mm thk, 50 x 100cm (19.5 x 39") ...............$119.99"

If you don't mind that a rock can take it out, it soaks up flammables, it is flammable, and it cost as much as scrap titanium, it might be okay.:)

*********
It depends somewhat on what you are trying to protect. General chassis protection should be a minimum of .125 6061T6. Other places and things should be designed as needed. Size, weight, and whether it must be removable should be considered.
 

HardCharger81

Well-Known Member
Posts
693
Reaction
27
I was thinking of using UHMWPE, Ultra high molecular weight polyethylene. I have a 5 x 10 sheet of it that's 3/8" thick left over from a
horse hospital corral I built. It's cool stuff. I've used it in cow and horse working facilities that I've built.
It's super hard, it can stand up to a horse kicking the s**t out of it. I thought it'd work great as a skid.
I'm sure others have tried it? It's also very slick on the suface, and chemical resistant.
 

Samco Fab

Well-Known Member
Posts
1,160
Reaction
392
Looking at stiffness vs weight and tensile strenth vs. weight in this fancy boatbuilding book that my Dad has, titanium looks pretty good for a skid material. It also would be thinner and harder than aluminum. You might be able to get a plastic material to work good, but you would loose a tiny bit of ground clearance. If your race car burnt to the ground, the Ti skids would be as good as new, very heat resistant!!!

Anybody have a sheet of 1/8" titanium laying around that they sell for cheap?

What different Ti alloys are there commonly and what one would work for skids? Whatdrawbacks are there other than the obvious $$$ ?
 

Samco Fab

Well-Known Member
Posts
1,160
Reaction
392
I was thinking of using UHMWPE, Ultra high molecular weight polyethylene. I have a 5 x 10 sheet of it that's 3/8" thick left over from a
horse hospital corral I built. It's cool stuff. I've used it in cow and horse working facilities that I've built.
It's super hard, it can stand up to a horse kicking the s**t out of it. I thought it'd work great as a skid.
I'm sure others have tried it? It's also very slick on the suface, and chemical resistant.
How stiff is this material? I think that rockcrawler guys use this quite commonly for skids, it slides better over rocks and does not hang up the foreward progress. That might help a little bit in high speed stuff, but probably not as good of a selling point.

Does the UHMWPE burn very easily?
 

BajaFand

Well-Known Member
Posts
2,188
Reaction
733
How about a .125" full skid for under the car with .250" delrin on it? For the front and under the motor/trans area go with thicker 5052 AL with delrin on that as well. It seems like delrin would slide over rocks easier and not gouge as much.
 

HardCharger81

Well-Known Member
Posts
693
Reaction
27
Samco, I know it doesn't have a very high melting point. I ruined a piece of it welding/cutting to close to it.
I wouldn't say it burns, but it does melt.
I'm not a material engineer, but I was told that its harder than stainless steel by quite a bit.
The way I found out about it was I did some contract work for a friend of mine thats a millwright.
We replaced the conveyors in a food processing plant. All the conveyors were stainless, not sure what grade.
But the guides they rode on were UHMWPE. The conveyors had actually visibly worn from running against the UHMWPE.
The plastic look almost new. I had never seen the stuff before then, and I did alot of work for my dad in the dairy
industry at the time. So we bought some and started using it in some of the things we made for dairies, horse ranches, etc...
The 3/8" ish (I'm not sure exactly how thick it is, never bothered to look, its a factory second.) sheet I have seems considerably stiffer than Aluminum. Way more impact resistant.
 

Wendell #527

Well-Known Member
Posts
1,660
Reaction
908
This is interesting. I have a 3/16" thick 6061 T6 skid plate and it definitely needs to be thicker. A large rock punched in a dent that actually went through the skid plate and dented the chassis. I was going to go to 1/4" on the whole thing. Maybe Aluminum isn't the bomb to use...
 

Samco Fab

Well-Known Member
Posts
1,160
Reaction
392
They use the UHMWPE in bullet proof vests in fabric form. It obviously absorbs energy, and mabye this is a good thing in a skid.

I would worry it would not be rigid enough, and transfer load into the chassis and dent it. I may go to the plastic store and get a test sample and beat the hell out of it.
 
Top