What gauge for a Football push/pull sled?

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Going to be building a push/pull sled like one of these, but not sure what gauge steel I should go with.As not to skew anyone's answer, I won't say what I was thinking for thickness.I was thinking:2x2 box tubingthe vertical tubes will be 2" DOMthe horizontal tubes will be 1.5" DOMSo what gauge would you go with?Also what thickness would you use for the ski's?These really don't need a lot of weight added to them to murder you, max would be 4 (45 lb plates).
Reply:Coincidentally, I joined this forum because I had some questions about AC rod types for exactly that project.  We finished it just in time for my older son to take it to college with him (he's a baseball player).It only has primer on it in this pic, but we literally sprayed it, and put it in the car so he could leave.  Cut it a little close on time, I'd say. Sorry about the washed-out picture.  I was in a hurry.  It looks better than that in real life.I did the cutting, fitting, and tacking, and had my son do all the welding.  We used 4 lengths of 2x2x3/16 tube, 36" long (got a good price on new 36" lengths), and 3/4" schedule 40 pipe for the horizontals.  The verticals are 1", fit into 1-1/4" sockets.  They had to be removable for easy transport, and the 1-1/4" pipe is 1-3/4" OD, so it's a nice fit for plates with a 2" hole.  The 1" fits very closely inside the pockets, so they don't slop around.I closed the ends of the square tubes with some gauge metal caps.Skids are 1/4" plate, which I cut most of the way through with an angle grinder and cutoff wheel, then bent cold in a vice.  A single pass on top to heal the cuts.  It's hard to see, but I cut a chain link in half for the hitch on the front - I though it looked better than the rings cut from pipe, which some in your pics have.  Got a couple of large chain links for free from the BORG, just by asking.All welding was done with my old AC buzz box, using 1/16" 7014 for the end caps (about 50A), 3/32" 7014 for the cross bars (about 80A), and 1/8" 7014 for the tubes (about 120A).  I tried 7018AC, but the arc would blow out constantly, so I gave up and stayed with 7014 Hobart rods from Tractor Supply.I should probably update the post where I solicited rod advice, come to think of it.
Reply:Hello GroupUnless you want your workshope to look like this, I wouldn't use a cloth dropsheet anywhere near a welder.The photo only shows some of the carnage, the timber on top of the welder / table is the roof.Ed Attached Images
Reply:^Damn that sucks.tkanzler that is Awesome!!  Great job.  Your son must love/hate it.  If you know what I mean.Huge help thanks so much for the info.I was thinking going 11 gauge (1/8") for the box and DOM tubing.And 3/16" sheet for the ski's.Maybe 3/16" box and 1/4" sheet is the way to go.  How heavy do you figure it ended up being?  Probably kinda hard to tell now that it's out of your shop.I like the use of schedule 40 pipe, that would lower my cost.Big thanks!!
Reply:Thanks.  And yes, he's enjoying hating it.  They're doing 'conditioning' right now, which is secret strength-trainer code for beating them till they hurl (several players, so far), pass-out (the catcher), or quit (nobody yet).   As far as weight goes, 2x2x3/16 tube is 4.32 lb/ft, and I used a 12 ft stick (purchased as 3 ft lengths), so the tube weighed 52 lb.  Three of them made the triangle, and the rest made the stubby legs, short cross bar, and vertical tree trunk.I think the tall pipes were 42 long, but I'd have to measure what's left after I cut a 10 footer, but assuming 3-1/2 ft, 1" sch. 40 black pipe is 1.68 lb/ft, so for 7 ft, that's just under 12 lb.The sockets were 1-1/4" sch. 40, 1 ft long each, so at 2.27 lb/ft, that's 4.5 lb.Skids were, I think, 1/4" plate, about 4" x 8", times 3, so that's about 6.8 lb.Horizontals were about 2 ft or so each, 3/4" sch. 40 at 1.13 lb/ft, so that's 4.5 lb.  Maybe a little more.There's also a plate on the front, and one for the front leg (I ran out of tube), so maybe that's another 5 lb.That totals around 85 lb.  If I had it to do over, I'd try to use 11 gauge and hope for the best.  Welding the thin stuff is a challenge with my buzz box (my son blew out one of the two 3/4" pipes, but I was able to fill it), but someone with actual skill, and maybe a DC machine, might have an easier time of it.The 1" schedule 40 pipe has an OD of 1.315", while the ID of the 1-1/4" sch. 40 is 1.380" (published values), so it's a real nice, close fit for the verticals.One other caution - I used a 1-1/8" hole saw to drill the vertical tube for the 3/4" pipes (OD=1.05"), but with the chatter, the hole came out big.  It probably would have been a perfect fit with a 1" hole saw and the chatter making it a touch oversized.  The oversized hole had a lot to do with the blow-out during welding - probably wouldn't have happened with a better fit-up, as the material was plenty thick for 3/32" 7014 rod on AC.Oh, and some commercial units are made with removable/replaceable skids, but I didn't have time to get fancy, so I figure if they wear out, we can either cut them off and replace them, or just add a wear plate to the bottom and feather the joint.  Or hit it with hard facing rod.  But the biggest benefit is the time together making this thing.  My younger son (a HS soccer player) now wants to make a glute ham raise (GHR) machine, which is why I'm thinking 11 gauge.  Similar to a weight bench, it doesn't have to qualify as a boat anchor to work, and extra weight is not of any utility, assuming it's well designed and constructed.  Stay tuned . . .
Reply:Awesome detail, much appreciated!!!Yeah the Prowler Flu is deadly. [ame]http://www.youtube.com/watch?v=1ieOBgyq88E[/ame]Can't wait to build this, hopefully in a couple weeks will have some time to get at it.A GHR bench would be awesome.  Great exercise, but as you know, stupid expensive $500 up to $1000+.Thanks again for the help!!