Environmentally Friendly Snowboards and Skis
Moderators: Head Monkey, kelvin, bigKam, skidesmond, chrismp
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knightsofnii
- Posts: 1148
- Joined: Tue Jan 08, 2008 6:02 am
- Location: NJ USA
- Contact:
http://en.wikipedia.org/wiki/Sinteringif TIVAR is UHMWPE, then it is "sintered", the process determines the product. Sintering produces uhmw, extruding produces HDPE or "extruded" base. They both originate as the same polyethylene beads.
http://en.wikipedia.org/wiki/UHMW
http://en.wikipedia.org/wiki/Hdpe
G-man
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knightsofnii
- Posts: 1148
- Joined: Tue Jan 08, 2008 6:02 am
- Location: NJ USA
- Contact:
oops my bad, thanks g-man...G-man wrote:http://en.wikipedia.org/wiki/Sinteringif TIVAR is UHMWPE, then it is "sintered", the process determines the product. Sintering produces uhmw, extruding produces HDPE or "extruded" base. They both originate as the same polyethylene beads.
http://en.wikipedia.org/wiki/UHMW
http://en.wikipedia.org/wiki/Hdpe
G-man
though i'd swear i read all of what I said somewhere, anyway thanks not for making me look dumb but for making me a little smarter
is extruded base still uhmw?
Doug
Hey Doug,
One of the downsides of the 'information age' is that there are such unlimited sources of information out there, they're almost certain to not always agree with one another. I'm certainly not saying that wikipedia is always correct, but I often use it a a starting point for much of my research. Then, when I get to the point where I'm researched-out, I still usually end up only forming a slightly vague opinion that is based on the general consensus of what I've read. I passed on the above links only to give readers an additional source of info/perspective. There seems to be as much disagreement across the internet regarding sintered vs. extruded polyethylene as there is disagreement on any other subject (except politics), so it's quite easy for different impressions of the 'truth' to arise.
Regarding your question whether or not extruded base is still UHMW, I really haven't read of anyone using an extruded UHMW product for ski bases that are intended to be waxed. It seems that extruding UHMW results in a very non-porous product, and that the extrusion process is used primarily due to it's production efficiency (making continuous sections of formed rods, bars, angles,etc.). But, it certainly seems that an extruded form of UHMW is used extensively in the manufacturing industry. Here's a link that talks a bunch about extruded UHMW:
http://books.google.com/books?id=Fu7yMa ... MW&f=false
A couple of years ago, skibuilders.com had plans to get a Durasurf rep. to respond to a question and answer forum. It never materialized, but it sure would have been interesting to have a Durasurf product person chime in on this subject.
Cheers,
G-man
One of the downsides of the 'information age' is that there are such unlimited sources of information out there, they're almost certain to not always agree with one another. I'm certainly not saying that wikipedia is always correct, but I often use it a a starting point for much of my research. Then, when I get to the point where I'm researched-out, I still usually end up only forming a slightly vague opinion that is based on the general consensus of what I've read. I passed on the above links only to give readers an additional source of info/perspective. There seems to be as much disagreement across the internet regarding sintered vs. extruded polyethylene as there is disagreement on any other subject (except politics), so it's quite easy for different impressions of the 'truth' to arise.
Regarding your question whether or not extruded base is still UHMW, I really haven't read of anyone using an extruded UHMW product for ski bases that are intended to be waxed. It seems that extruding UHMW results in a very non-porous product, and that the extrusion process is used primarily due to it's production efficiency (making continuous sections of formed rods, bars, angles,etc.). But, it certainly seems that an extruded form of UHMW is used extensively in the manufacturing industry. Here's a link that talks a bunch about extruded UHMW:
http://books.google.com/books?id=Fu7yMa ... MW&f=false
A couple of years ago, skibuilders.com had plans to get a Durasurf rep. to respond to a question and answer forum. It never materialized, but it sure would have been interesting to have a Durasurf product person chime in on this subject.
Cheers,
G-man
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threeninethree
- Posts: 172
- Joined: Fri Feb 23, 2007 8:11 pm
- Location: Massachusetts
Entropy epoxy kits from there store:
http://www.entropysports.com/store/category/Epoxy+Kits
Dont know why but I had posted this link yesterday but it my comment wasnt in the thread today....strange?
http://www.entropysports.com/store/category/Epoxy+Kits
Dont know why but I had posted this link yesterday but it my comment wasnt in the thread today....strange?
~ Matt
Entropy Bio-Resins
Man, should have figured...there is no way to sneak anything past the SkiBuilders forum! Thanks for posting the link Matt. The store is going to go live for resins tomorrow but if you want you can hit it now and help us with doing Beta testing!
Desi here from Entropy Sports soon to be Resins. Just wanted to start by setting the record straight about the Signal youtube video. THE RESIN IS NOT EDIBLE! For that matter no epoxy that is used for composites and worth a damn mechanically would ever be edible. We've been working with those guys to develop the resin and Daniel their head engineer came up with that idea. We had nothing to do with it and have since asked them to remove it. Sorry for any confusion or misinformation it may have created.
We do believe we have a great product for composites and legit alternative to today's petrochemical based epoxy systems. Our bio-mass sources are from the industrial waste streams of pine pulp processing used for things like paper and vegetable oil processing used for bio-fuels. We are able to reduce the petrochemical content of the resin by up to 70%. Our resins have excellent adhesion and elongation properties that make for strong composites for things such as skis and snowboards. As you can see we've been using it on our our own snow and surf products but have also been working with companies such as Signal to bring it to the masses. Keep an eye out for your favorite brand rocking some bio-epoxy!
As you can see from the store there are three base systems, one room temp cure systems (100/1000) , one heat accelerated cure system (100/1100), and Surf Sap our laminating/coating resin designed specifically for the surfboard industry. The heat cure system was designed for "production" environments so its pot life may be a bit too quick for the home builder (~25 min) but in a heated press it's lightening fast, 15 min cures at 180F. The ambient temp system would work for those looking for a bit slower pot life or have a non-heated press. Cure schedules for those resins 2-3 hrs (obviously this depends upon your ambient temp).
We are still in the process of updating our resins website with all the info about the materials but feel free to hit me with any questions. We love this forum and would never have been able to get where we are with our snow products if it wasn't for the clever and curious (sometimes too curious) contributors to this forum.
-Desi
Entropy Sports/Resins
http://www.entropyresins.com
http://www.entropysports.com
Desi here from Entropy Sports soon to be Resins. Just wanted to start by setting the record straight about the Signal youtube video. THE RESIN IS NOT EDIBLE! For that matter no epoxy that is used for composites and worth a damn mechanically would ever be edible. We've been working with those guys to develop the resin and Daniel their head engineer came up with that idea. We had nothing to do with it and have since asked them to remove it. Sorry for any confusion or misinformation it may have created.
We do believe we have a great product for composites and legit alternative to today's petrochemical based epoxy systems. Our bio-mass sources are from the industrial waste streams of pine pulp processing used for things like paper and vegetable oil processing used for bio-fuels. We are able to reduce the petrochemical content of the resin by up to 70%. Our resins have excellent adhesion and elongation properties that make for strong composites for things such as skis and snowboards. As you can see we've been using it on our our own snow and surf products but have also been working with companies such as Signal to bring it to the masses. Keep an eye out for your favorite brand rocking some bio-epoxy!
As you can see from the store there are three base systems, one room temp cure systems (100/1000) , one heat accelerated cure system (100/1100), and Surf Sap our laminating/coating resin designed specifically for the surfboard industry. The heat cure system was designed for "production" environments so its pot life may be a bit too quick for the home builder (~25 min) but in a heated press it's lightening fast, 15 min cures at 180F. The ambient temp system would work for those looking for a bit slower pot life or have a non-heated press. Cure schedules for those resins 2-3 hrs (obviously this depends upon your ambient temp).
We are still in the process of updating our resins website with all the info about the materials but feel free to hit me with any questions. We love this forum and would never have been able to get where we are with our snow products if it wasn't for the clever and curious (sometimes too curious) contributors to this forum.
-Desi
Entropy Sports/Resins
http://www.entropyresins.com
http://www.entropysports.com
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LifeisRiding
- Posts: 80
- Joined: Sat Sep 26, 2009 7:21 pm
- Location: British Columbia
Thanks!
Hey Thanks for the information!
I originally posted the video on this thread, as i was so amazed that he was putting the resin in his mouth!
Its awesome what you guys at Entropy are doing. Keep up the good work!
I originally posted the video on this thread, as i was so amazed that he was putting the resin in his mouth!
Its awesome what you guys at Entropy are doing. Keep up the good work!
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skidesmond
- Posts: 2337
- Joined: Tue Apr 07, 2009 3:26 pm
- Location: Western Mass, USA
- Contact:
Entropy Bio-Resins
Yeah, I almost passed out when I first saw it. Our bad...
So all our resins are 2 to 1 mix ratio by weight. The 3qt kit is composed of 2qts of epoxy, 1qt hardener. The number of skis you can make with that amount of resin will obviously vary on your lamination technique but I would venture to say you should get at least 2-3 pairs out of that quantity. That size kit is actually for surfboard builders and is considered a 1 board kit but for skis it should be a good quantity to at least build a few pairs.
So all our resins are 2 to 1 mix ratio by weight. The 3qt kit is composed of 2qts of epoxy, 1qt hardener. The number of skis you can make with that amount of resin will obviously vary on your lamination technique but I would venture to say you should get at least 2-3 pairs out of that quantity. That size kit is actually for surfboard builders and is considered a 1 board kit but for skis it should be a good quantity to at least build a few pairs.
Before I get myself into trouble, let me just quote gel times that we have in our tech data sheets and have been measured experimentally. Of course the ambient temperature of your working area has an effect on these gel times so in my shop we get longer working times as its much cooler.
Gel Times (150gm mixed at 25C)
100/1000: 22-25 min
100/1100: 20 min
We have not measured the cure times for the 100/1000 system at 180F and my recommendation is that if you are using any heat to use the 100/1100 system as it has been optimized for that. If the pot life for 100/1100 is too fast for you then I'd recommend mixing in two batches as opposed to one large batch.
We do have a longer pot-life heat cure system that we may make available to retail customers soon. If/when that happens I'll be sure to post it.
Desi
Gel Times (150gm mixed at 25C)
100/1000: 22-25 min
100/1100: 20 min
We have not measured the cure times for the 100/1000 system at 180F and my recommendation is that if you are using any heat to use the 100/1100 system as it has been optimized for that. If the pot life for 100/1100 is too fast for you then I'd recommend mixing in two batches as opposed to one large batch.
We do have a longer pot-life heat cure system that we may make available to retail customers soon. If/when that happens I'll be sure to post it.
Desi
