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Thread: UHMW vs. HDPE for cheap freight sled runners

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    Default UHMW vs. HDPE for cheap freight sled runners

    I've been looking for a less expensive material for my freight sled bottom and had what I hope will turn out to be a brainstorm. I use 30 gal. plastic barrels (soap barrels from a carwash) for fuel storage and noticed the plastic seems to be similar to UHMW. The code on the barrel is HDPE, and a few websites I found said it performs well as runner material. I think if cut at a slight diagonal you could get some nice long strips of it and it would go a long way. I know it's softer than UHMW, but it seems like a very inexpensive alternative. Anybody out there tried this material with success?

    blt

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    I made a Barrel Sled this year but haven't tested it as yet .
    I cut the ends out of a plastic barrel then one cut to make a
    sheet and sandwiched it between two sheets of plywood with weight on top for a week to try to make it flat. I couldn't get the plastic to lay perfectly flat when i attached it to the glued an nailed wood frame I made.

    Narrow strips of barrel plastic would be easier to work with.
    But for the price why not give it a try .Its tough stuff. Can always double it.
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    Member Erik in AK's Avatar
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    salvaged hyfax's work well too

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    Default plastic difference

    HDPE= High Density Polyethylene
    UHMW= Utra High Molecular Weight
    UHMW will give you quite a bit more life than the same thickness of HDPE. The friction co-efficient is less, therefore it is slicker. If you had to buy both, it would take a heck of a big discount for me to purchase HDPE. But, if you have old drums that you don't care about, and the time to put into it, it certainly won't hurt to use strips as runners.
    Most of the cheap sleds are HDPE. The whole sled does not seem to hold up as well as the UHMW sleds, but then to be fair, nobody builds a UHMW sled like the factory molded HDPE sleds. A direct comparison is a little subjective.
    The nice thing about UHMW is that you can get strips that are thicker than you can normally find HDPE. That would allow you to raise the sled up a bit higher if it were important. That would also make it easier to hide or protect your mounting hardware.
    Try talking to the musher supply houses. See what they have for runner material for dog sleds. Never know, maybe they have some old stock or stock that is too short for the intended purpose that you could use on your sled.

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    Quote Originally Posted by Erik in AK View Post
    salvaged hyfax's work well too
    Erik, good tip man. This article says their usually UHMW, so even better yet! I know I'll be saving mine from now on...

    Plus, if you absolutely needed a certain color, then you might be able to find it

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    Default more numbers

    Quote Originally Posted by ak river rat View Post
    hdpe= high density polyethylene
    uhmw= utra high molecular weight
    uhmw will give you quite a bit more life than the same thickness of hdpe. The friction co-efficient is less, therefore it is slicker. If you had to buy both, it would take a heck of a big discount for me to purchase hdpe. But, if you have old drums that you don't care about, and the time to put into it, it certainly won't hurt to use strips as runners.
    Most of the cheap sleds are hdpe. The whole sled does not seem to hold up as well as the uhmw sleds, but then to be fair, nobody builds a uhmw sled like the factory molded hdpe sleds. A direct comparison is a little subjective.
    The nice thing about uhmw is that you can get strips that are thicker than you can normally find hdpe. That would allow you to raise the sled up a bit higher if it were important. That would also make it easier to hide or protect your mounting hardware.
    Try talking to the musher supply houses. See what they have for runner material for dog sleds. Never know, maybe they have some old stock or stock that is too short for the intended purpose that you could use on your sled.
    rat,
    coeff of friction:
    uhmw=.25
    hdpe=.31
    density:
    uhmw=.04
    hdpe=.025

    I have no idea what these mean, but they make comparison pretty easy.
    to give you some cost comparisons, a quote yesterday from a Seattle vendor:

    1/4"x4'x10'
    black virgin uhmw $184
    hpde $79 (didn't get color, probably black.)
    for 1/2' thick exactly double.

    comes in roll stock as well 100' and 250' for 1/2x3''UHMW prices only)
    virgin wht $2.07 ln ft repro black$1.52 same unit price either roll.

    I have sold lots of the roll stock to guys trying to repair the factory molded hdpe sleds, they wear thru on the bottom or shatter in several years due to uv breakdown. Some guys have started beefing up the bottoms with uhmw runners of new sleds in the hope of longer service life. It looks hopeless to me and in my opinion these are very overpriced sleds.

    Several guys are building a nice looking uhmw sled in the Fairbanks area, the guys out here (sw ak) really put them thru hell, but can't seem to break them. More expensive, but a much better value it seems.

    By the way, even uhmw is very susceptible to uv breakdown. With black being the most uv resistant. I built a sled several years ago with virgin white and was careless about it's summer storage, it's crazing all over the place and expect it to shatter next winter. Maybe it will make a good Mother's day present for my so miserable without you it was almost like you were here sister-in law.

    Good sleds are expensive to buy and/or expensive and time consuming to build I wouldn't cheap out on the runners.

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    Default Old thread, WOW!!

    Interesting bringing up old stuff. I'll take a closer look at the number and sort it out a bit. As I recall, the lower the number, the slicker it is, or the less friction it causes.
    A few notes:
    Black- I do not believe it is more UV resistant. It is "recycled" or "reconstituted". It is NOT virgin. Usually a lower grade, cheaper, and harder than virgin material. I would never pay the same amount for black as I would for a color that had the UV inhibitor. Show me the numbers that prove it is more UV resistant and I will say "thank you".
    White- Always virgin, normally not UV inhibited.
    Colored- Only UV inhibited if made to that spec.
    Yes, all plastic is affected by sunlight....
    As for taking the time to build a sled, I think spending the cash to call somebody like Mike at Superslide and order some of their product makes more sense than salvaging poly drums. Don't get me wrong, I am cheap. But it takes me about 11 hours to build a sled if all goes well. I do not want to build a new sled every year when I can build one UHMW sled and have it last for 8 or more years.
    If you have not looked, go to my link or home page or whatever they call it and I've got some photos of the most recent sled I built.

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    Much more UHMW varieties available. Some are super-slick as they've been heavily blended with molybdenum disulphide. Also, there are others with a super-high impact resistance used in the beds of giant off-road trucks. The standard stuff available for runners in-state is the low-end.

    Do some google searches and you'll find some really exotic UHMW polyethylene formulations.
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    Just for the record, on how the coefficient of friction works...

    if you multiply the weight on the sled by the C.O.F. you generally get the "friction force" which is the force you have to overcome to break the sled loose...once it's moving the friction becomes less..

    And, that coefficient is based on the interaction..ie, metal on ice, UHMW on snow, etc,...since both the sled and the trail contribute resistance to movement...so those listed numbers are based on sliding over some other material (maybe steel?) for reference...

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    Default just checkin' in

    Quote Originally Posted by Ak River Rat View Post
    Interesting bringing up old stuff. I'll take a closer look at the number and sort it out a bit. As I recall, the lower the number, the slicker it is, or the less friction it causes.
    A few notes:
    Black- I do not believe it is more UV resistant. It is "recycled" or "reconstituted". It is NOT virgin. Usually a lower grade, cheaper, and harder than virgin material. I would never pay the same amount for black as I would for a color that had the UV inhibitor. Show me the numbers that prove it is more UV resistant and I will say "thank you".
    White- Always virgin, normally not UV inhibited.
    Colored- Only UV inhibited if made to that spec.
    Yes, all plastic is affected by sunlight....
    As for taking the time to build a sled, I think spending the cash to call somebody like Mike at Superslide and order some of their product makes more sense than salvaging poly drums. Don't get me wrong, I am cheap. But it takes me about 11 hours to build a sled if all goes well. I do not want to build a new sled every year when I can build one UHMW sled and have it last for 8 or more years.
    If you have not looked, go to my link or home page or whatever they call it and I've got some photos of the most recent sled I built.

    river rat,

    I have been talking to Mike @ SS and your recommendation that I do this only corrborates my first impression of him...he da man. Thanks.

    On uv inhibition I have always been under the impression that the darker the pigment the higher the inhibitor value, so in general I would favor black all things equal and they are never are. The black color of repro comes from carbon added to the plastic in manufacture, If repro does not cut it for the sled you manufacture then black virgin could fit your needs, I have seen the folded from sheets of 1/4" UHMW sleds built from both and I too would not choose repro in black. All things being equal, because all of the blacks tend to absorb more heat which causes bubbling I wouldn't use it in virgin either I guess I spent a lot of words to agree with you , but was trying to show some of my reasoning for reaching same conclusion. So what would you recommend? Blue, red, yellow or something else?

    The customers that I service build a different sled, Probably more like a "sledge" and I sell them 2" to 4" wide by 8' to 12' long by 1/2" thick strips of UHMW in repro and virgin white. Uv does not affect this material in their application. It is the perception of most of my customers that the two materials perform comparably. I am a mere retailer so I don't argue with people's perceptions, I just try to supply them. That does not mean I am not a seeker of the truth and would appreciate your input. I would also like to look at your sled but don't know where to find the web site you mention.

    j

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    Member DRIFTER_016's Avatar
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    If you're looking for cheap sled runner material you need to head down to your local ice rink and have a chat with the manager. During the summer is best as that is the time they do maintenance and replace worn puck board.
    Yep that white stuff that keeps the puck in the ice surface. The bulk of the material is 3/8" or 1/2" but the base board is about 3/4". The best thing is they will usually save it for you and it is free as they were just going to toss it out any way. The base board stuff is great for making ski runners for your sled trailer (really saves the decking from the carbides).

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    Default Hunts too

    I posted pictures on my personal page, or whatever you call it. Heck, I am not hardly computer literate enough to even know.
    Years back guys had color preference for use on the sprint dog sleds. A buddy of mine who was a cross country ski racer got into waxing their sleds for them. I can't really tell you that one plastic was better than the next.
    If a guy thinks blue is bomb, sell him blue. He'll be forever grateful. Most guys won't take the time to test out a theory. As long as you sell them UHMW that is UV inhibited it really won't matter a bit.
    If they are using it for bottoms on solid runners, I wonder if Superslides Iron might work better? It is supposedly even more wear resistant. I think they make blue, red for hot stuff, and yellow? If I got it right, the yellow might be a bit harder or more wear resistant. Go check with Mike.
    Oh, I think one of the mods posted a picture of my sled on this forum on the UHMW sled thread. You might take a look there too.
    Essentially my sleds are similar to the ones that Dave over at Northern Sledworks builds. He does nice work on his. They are a bit more finished than mine are, but then I don't have picky customers to deal with.

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    I pulled screw heads right through my HDPE; never done that with any of the UHMW runners I've seen or used.

    Similar experiences going over rocks and debris with the sled(s). The UHMW is where it's at, if you want to minimize the number of times you'll do the same job..

    And, personally speaking, the black UHMW, imo, is slicker on the snow and ice that the HDPE, creating/causing less drag. That also means, however, that it's that much more likely to be of benefit if you have skags/skegs on the sled, to prevent it from passing you on side-slopes, polished ice, etc.

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    Old threads never die, wow. Depending on what you are doing, yes, both materials are good. But comparing the 2 is like comparing hardwoods and softwoods (aspen vs oak).
    Black, being a recycled product, is usually harder and less flexible than virgin material. To date I've never had a virgin UV additive sled break or crack where it tends to bend in the middle. I'd be interested to have the same number of miles on the same designed sled built in black. The black might be slicker as it is harder. Just a guess. Likely it would be more important if you or your huskies were dragging the sled as compared to a high horsepower machine. A little bit slicker won't really matter at that point.
    I'd agree with the screws pulling through the HDPE as compared to the UHMW. If you were using a flush mounting screw especially in HDPE I'd suggest buying some dimple washers and countersinking the hole in your material a bit. You can find the dimpled washers at good industrial hardware stores, or they are used in Aviation a lot. You can find them in stainless and mild steel.
    I use flush mounted screws for my skegs and normally just suck them down tight without the washers. That way I don't have a head of a bolt sticking up to wear through the bottom of a gas jug or something.
    FYI, this spring I've put 120 odd miles on the Superslide Sled carrying firewood for 1/2 of those. That sled still looks perfect. The welds show zero signs of stress. Guess I better get off my butt and go haul some more wood.
    ARR
    ARR

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    I always counter-sink, but with the right screws, the trim washers aren't always used; a good wide (flat-on-the-underside) pan-head screw with the right cut threads to go into what ever material is beyond your UHMW runner has sufficed well for me. It's also been my observation, as stated earlier, that the black is slicker and tougher.. Not to mention, if you approach Alaska Rubber & Rigging, or similar outfits, they'll quite often have long narrow scraps from cutting jobs for others that will suffice, and are very reasonable in pricing.


    If I were to re-do my current barge-type sled, I'd go with 3-1/2" or 4" wide UHMW runners, as opposed to the 2-1/2" or 3" that I have on there now.

    I also run a thin aluminum 'belly pan' down the bottom center of the sled, full-width between the runners, to protect the frame from debris, etc.

    Once you get thicker than the 1/4" thickness in the black, you're in for a a bit of a wrestling match, if you intend to contour it to any seriously-tight arching in your runner design; been there and done that with some 1/2" and 5/8" material. With 3/8" black you can use a heat gun, or even an adequately hot hair-dryer to heat the material as you're arching it. If applying it to tight curves like that, I go for longer more solid screws, to avoid it pulling out.

    With my larger wooden freight sled, I have the benefit of custom cut and rasped 2"x8"s, so I can put a 3" counter-sunk screw into that with no problem. Dog sleds typically have much thinner lighter materials, and pose another issue altogether, unless beefed up at the points where the screws sink.

    My next project will involve first finding someone who does reputable aluminum frame welding (I think I've found them.. maybe..), and have a similar structure/skeleton-frame built to that of my current barge-style wood sled, with shaped corrugated aluminum runners with holes to eather side of the center strut to accept machine screws to bind the UHMW to the aluminum runners with counter-sunk machine screws and accompanying nute and washers on the top side of the runner.

    The current sled, with large freight box and mega-amounts of D-rings attached to the exterior, weighs in at about 140 lbs.+, empty. I figure I can get that down to 35% or 40% of that by utilizing an aluminum skeleton of a frame, and an aluminum or glavanized tin box, with similar D-ring fixtures to the outside.. Big enough to put 9 or so 5-gallon fuel jugs into the box, with room inside the box above the jugs, space on the deck surface -around- the box (which sits toward the rear of the deck fo rbalance in pulling), plus the D-rings to attach other items, tarps, axe, auger, etc. to the exterior of the box.

    Another project for another wind-fall... Someday..

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    bump to the top

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    My experience. HDPE abides more easily. UHMW PE is slicker and the surface much more durable. Virgin stuff is white and works better. Black is more brittle and expands/contracts to the point of being a problem. For my money I'll use virgin white UHMW for my projects that require application of plastics. Doing some airplane skis now w/countersunk screws. Bought the UHMW at Image Plastics who had the best pricing I could find locally. It'll re-do the runners on one of my freight sleds this winter. On that sled I use a spade bit to make a slight relief/countersink at rivet locations and affix the plastic with wide head steel rivets of the same diameter of the spade bit so the rivets lay flush. In the years I've dragged that sled I've had very few rivets snag and fail. And that sled gets abused as a rule.

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    Mr. Pid,
    Good morning and good to hear from you. Virgin UHMW is polyethylene that does not have reprocessed material in it, but it can be white or colored. Black by standard is reprocessed, or recycled material, therefor not virgin. White is not UV resistant. Well, to be more exact, any UHMW is not UV resistant unless it has an additive to be so. White is ok, but the sun will get to it quicker and cause it to craze, get brittle, and crack. For the money, UV resistant is well worth any minor additional cost. Personally, I'd hesitate to use any non-UV material for any outdoor application unless I could store it completely out of the sun when not in use.
    Just a few thoughts on a subject that I have spent some time with. There is so much good information in these threads, that is why I bumped them all to the top. Take care, have a great day,
    ARR

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    My earlier first comment should have said HDPE becomes abraded more easily. Darn spell check! The UV comments are interesting but don't apply to my use for ski and sled bottoms. All my UHMW (Tyvar) is applied to the bottom of aluminum fixtures, whether skis or runners. If they see the sun I'm having a bad day. Performance concerns for plastics used for those northern all-plastic sleds may be different.

    Happy Thanksgiving.

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