New Ski Making Workshop - Complete with Press et all!
Moderators: Head Monkey, kelvin, bigKam, skidesmond, chrismp
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Can of Worms
It seems if have opened up a big debate on the design of a ski press.
Heleski - I think your reply was a bit off key. You may have years of experience of working with metal, but my current job revolves around using structural steal on a daily basis. Mechanical engineers know about I beams but only graze the surface.
Any how, its not my nature to get into an argument, thats what the forum is here for the encourage debate.
To clarify for those, the steels are structural. It means that the are made from one bilet of steel that comes out of a factory in a rectangle. It is then forced through rollers that make the steel into a forged shape. This gives the steel great strength as oposed to a welded beam, which i agree strongly with all would fail at a much lower load due to the load being its strongest at the welds which are the weakest point of a non-structural I beam.
Thanks for everyones coments. Deflection is the real worry of the press. I have calculated what it should theoreticaly deflect but it wont find out until i do a test run and measure the true deflection.
Three31 - Your point about welding plates. The photos i think at the begining show the front plates that are on the end steels to provide the extra structural integrity.
I've just been on holiday and will post the designs and drawings to answer the many questions.
Heleski - I think your reply was a bit off key. You may have years of experience of working with metal, but my current job revolves around using structural steal on a daily basis. Mechanical engineers know about I beams but only graze the surface.
Any how, its not my nature to get into an argument, thats what the forum is here for the encourage debate.
To clarify for those, the steels are structural. It means that the are made from one bilet of steel that comes out of a factory in a rectangle. It is then forced through rollers that make the steel into a forged shape. This gives the steel great strength as oposed to a welded beam, which i agree strongly with all would fail at a much lower load due to the load being its strongest at the welds which are the weakest point of a non-structural I beam.
Thanks for everyones coments. Deflection is the real worry of the press. I have calculated what it should theoreticaly deflect but it wont find out until i do a test run and measure the true deflection.
Three31 - Your point about welding plates. The photos i think at the begining show the front plates that are on the end steels to provide the extra structural integrity.
I've just been on holiday and will post the designs and drawings to answer the many questions.
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Heliski you are completely wrong. sorry.
The pic I posted from E- Funda is exactly how I - Beams are to be oriented.
Your pic suggests that in fact the flange should be horizontal. That is absolutely 100% incorrect. The flange of an I-Beam should always be vertical.
I am done arguing this. If you can find anything supporting your opinion I highly suggest you post it.
The pic I posted from E- Funda is exactly how I - Beams are to be oriented.
Your pic suggests that in fact the flange should be horizontal. That is absolutely 100% incorrect. The flange of an I-Beam should always be vertical.
I am done arguing this. If you can find anything supporting your opinion I highly suggest you post it.
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Doughboy, Your picture is completely correct, but the vertical component is called the web and the two horizontile plates are known as the flange(s) i think you may have the terms confused. Using the beam with the web in the vertical position allows the beam to be fully utilized, in this orientation you are using the strength of the web which inreases the strength of the beam exponentially with the greater distance between the flanges.
The press pictured may very well be fine but when looking at over 10 tons of pressure (high pressure airbag) you always want to be careful.
For more information http://en.wikipedia.org/wiki/I-beam
The press pictured may very well be fine but when looking at over 10 tons of pressure (high pressure airbag) you always want to be careful.
For more information http://en.wikipedia.org/wiki/I-beam
skishaggys.com
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interesting fact
A 1" grade 8 Bolt is only as strong as 1" of a 3/8 fillet weld.
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http://www.americanfastener.com/technic ... _steel.asp
A grade 8 1" bolt has a yield strength of 130,000 psi.
Are you suggesting that a 3/8" thick fillet weld 1" long has the same yield strength?
If so can you post how you came up with that? I am curious.
A grade 8 1" bolt has a yield strength of 130,000 psi.
Are you suggesting that a 3/8" thick fillet weld 1" long has the same yield strength?
If so can you post how you came up with that? I am curious.
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made it up in my head
that is a fact that i learned in the 1st week of welding class. It was 6 yrs ago. you can find the calc. online if you want. as far as rod if you had a 13018 rod it would have a strength of 130000 psi
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i dont know about calculating or comparing to bolts. but that doesnt surprise me a whole lot. I do know that a proper weld should be at least as strong as the metal that was joined. so if you were to weld steel, it should be pretty solid. that doesnt really help, but i havent posted anything in a while.
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only if its welded properly with the right thickness, etc.
The only welds i've seen blow out in a press were because the press was literally torched in half for transportation, then welded together in a spot where the beam deflection pretty much sheared it, just a result of a need to move the thing and not planning it out thoroughly.
if you weld it near the ends like most do here it should be fine. I prefer bolts because you can take the thing apart instead of having to cut it apart.
The only welds i've seen blow out in a press were because the press was literally torched in half for transportation, then welded together in a spot where the beam deflection pretty much sheared it, just a result of a need to move the thing and not planning it out thoroughly.
if you weld it near the ends like most do here it should be fine. I prefer bolts because you can take the thing apart instead of having to cut it apart.
Doug
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The 2008/2009 Season Ski Designs Launched - Custom Grpahics
This year we launch our first range of skis. The ski press is all but finished (pics to follow) and we've been working hard on our designs.
Check out this years range at:
http://www.cambilla.co.uk/cambillaskis/skis.htm
Our clothing range and technical range to be launched with skis at the metro ski show 2008 in October.
Any comments welcome.
Check out this years range at:
http://www.cambilla.co.uk/cambillaskis/skis.htm
Our clothing range and technical range to be launched with skis at the metro ski show 2008 in October.
Any comments welcome.
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