http://en.wikipedia.org/wiki/Ultimate_tensile_stress
http://en.wikipedia.org/wiki/Yield_Strength
http://en.wikipedia.org/wiki/Yield_(engineering)
http://en.wikipedia.org/wiki/Brittle
http://en.wikipedia.org/wiki/Stiffness
http://en.wikipedia.org/wiki/Elasticity_(physics)
http://en.wikipedia.org/wiki/Hardness
http://en.wikipedia.org/wiki/Young's_modulus
http://en.wikipedia.org/wiki/Thin_walled_beams
http://en.wikipedia.org/wiki/Plasticity_(physics)
http://en.wikipedia.org/wiki/Deflection_(engineering)
http://en.wikipedia.org/wiki/Beam_theory
http://en.wikipedia.org/wiki/Strength_of_materials
http://en.wikipedia.org/wiki/Materials_science
http://en.wikipedia.org/wiki/Fracture_toughness
http://en.wikipedia.org/wiki/Stress%E2%80%93strain_curve

Cabin fever already? Start researching the speed accuracy of hand held gps vs smartphone apps. Promises to be a lively debate over who's faster than who snow kiting this winter. When I'm done with wikipedia I'm going flying!

And?

I'm just sort of disappointed that these are all Wikipedia pages, give 'em some real reading materials Scudley! Like Smithells Metals Reference Book or any good steel reference book...
:wee:

Jeff, just put these up so that the next time metallurgy is in the topic and I say 304 has a strain to failure of 70% and 1018 a strain to failure of 10%, no one is going to tell me 304 is "more brittle" than 1018.
Crash - Popov and Beer and Johnston make great bed time reading, but I chose wiki as it is pretty concise and at a fairly basic level, everybody had access to, none of those links should take longer than half an hour to digest, and the math is at a level we should all be able to comprehend.

S

guess it comes down to being inside the box or outside the box,
been in a conversation with a few people the last few weeks about who can think outside the box and who thinks they think outside the box, those with a degree or without. not that I believe the statement but it has been said a number of times, "those that go to collage go because that's all they are able to do, pay to think like someone else".
think this one will start a little response?

as for being more or less brittle, the act of welding, whether correct or wrong will become a factor not published by wikipedia.
besides welding 304 to 1018 will open another round of remarks, guess they will both have a strain to failure of 40%.

Jeff, I completely agree about thinking outside the box, but it appears some people don't know what a box is and other are so far away they can't see it.
To predict the properties of the weld you are going to need information about the hardenability of the steel alloy and filler your going to use. Calculate the compositions in the fusion zones and look at what the hardenability of fusion zones. See Wiki on Jominy bar

Now, how your piece of 1018 304 would behave would depend on the geometry of how you joined them and the direction you applied the force. Because of the differences in the Yeild strengths of two materials if you did a but joint between two rods of the same diameter, applied tension down the axis and the joint did not fail: The strain would be almost entirely in the stainless steel and the failure would occur in the stainless because it would have deformed plastically long before mild steel resulting a reduced cross sectional area and therefore though both metals have the same force applied, the stainless has higher stress because of its reduced area caused by the plastic flow. So your guess was wrong. If the box is at mile two post two, you're a good ways past ship wreck sailing down towards the jetty.
good guess though.
S
You were sort of right about the strain at failure. If the two rods were of identical length at the start the strain at failure would be 35%

Jeff, I've always been of the mind that college teaches you how to learn, not so much what to think. Free thinkers can be educated, but being educated doesn't make you a free thinker.

Bob, you can free think as much as you want but no amount BS is not going to make annealed 304 stainless less ductile than annealed 1018 or make you able to make 1018 stronger by heat treatment. Free thinking is fine, but spouting BS is not free thinking, it is just spreading fertilizer.
Is there a relationship between the attitudes to learning expressed here and the US ranking 34th in the world for the math and science scores of its students? Number 34 and dropping.
S

I was hopeing for a bit more dialog in the simplicity of "Who gives a hoot".

With years of welding and certifications for materials most have never heard of let a lone know what its used for, and fabricating wood stoves to nuclear reactors, learning to use a grinder for 10 hours a day to supervising yearlong oil refinery shutdowns with dozens of crafts doing the remodel/repair, I figured out a long time ago that its not what is correct or proper that is important, its what YOU want. I have worked with hundreds of engineers over the years from civil to soils to structural to theorist.
At the end of the day I can only speak of 2 of those guys as knowing what was going on.

Stainless or mild steal is no difference. 304 or 1018 is only the correct name of material that some have used to make a buggy, along with fir, pvc, copper, or what ever else in available.

How come aluminum wasnt in the discussion? Carbon fiber buggies? Who really cares? We all can read till the cows come home and nothing will change. Until someone spends a hundred million dollars on a study of 308-1018 built buggies nothing will change. Those that know, those that think they know, and those who have no clue, and those that dont care, will not change the outcome or the proof one way or another.

Im going to built a buggy out of a bar of soap, is ivory better than dove?:D

Quote: Originally posted by Scudley

http://en.wikipedia.org/wiki/Ultimate_tensile_stress http://en.wikipedia.org/wiki/Yield_Strength http://en.wikipedia.org/wiki/Yield_(engineering) http://en.wikipedia.org/wiki/Brittle http://en.wikipedia.org/wiki/Stiffness http://en.wikipedia.org/wiki/Elasticity_(physics) http://en.wikipedia.org/wiki/Hardness http://en.wikipedia.org/wiki/Young's_modulus http://en.wikipedia.org/wiki/Thin_walled_beams http://en.wikipedia.org/wiki/Plasticity_(physics) http://en.wikipedia.org/wiki/Deflection_(engineering) http://en.wikipedia.org/wiki/Beam_theory http://en.wikipedia.org/wiki/Strength_of_materials http://en.wikipedia.org/wiki/Materials_science http://en.wikipedia.org/wiki/Fracture_toughness http://en.wikipedia.org/wiki/Stress%E2%80%93strain_curve

very nice ! it only scratches the surface but for layman use indeed helpful..i don't just love this i live it

Jeff, did you ever think in all those years of learning to run a grinder that may be the reason that you thought the engineers did not know what was going on was that it took you years to learn how to run a grinder.
S

Quote: Originally posted by Scudley

Jeff, did you ever think in all those years of learning to run a grinder that may be the reason that you thought the engineers did not know what was going on was that it took you years to learn how to run a grinder. S

fifteen minutes after they handed me the grinder it committed suicide by jumping off the scaffolding and falling 80 feet. After that I figured only rocket scientists need to spend more time on a grinder than that. not sure if they would even know how to open the box to get to the tool out let alone figure out what grinding wheel to use.
if those engineers knew what they were talking about we wouldn't need to use grinders, cutting torches, plasma arc cutters, band saws, sawzalls and all the other altering tools known to man.

When I weld up my idea for a fixed bridle camera mount I will expect you to critique it, OK?

Quote: Originally posted by Scudley

Bob, you can free think as much as you want but no amount BS is not going to make annealed 304 stainless less ductile than annealed 1018 or make you able to make 1018 stronger by heat treatment. Free thinking is fine, but spouting BS is not free thinking, it is just spreading fertilizer. Is there a relationship between the attitudes to learning expressed here and the US ranking 34th in the world for the math and science scores of its students? Number 34 and dropping. S

Jeff, I agree with you. Who gives a hoot. I'm thrilled that my buggy fits me well and has been able to handle every stress I've been able to throw at it without any failures of the metal or fabrication, all without me knowing what specific kind of metal it is made of, or even knowing much about words like "annealed" and "ductility". But I must say Pythagoras has always been my hero.

I think the only cure for all this *** talk is a run down the beach (or lakebed) at 40 +

Quote: Originally posted by RonH

I think the only cure for all this *** talk is a run down the beach (or lakebed) at 40 +

the first time I read the post I thought it said to run down someone at the beach or lakebed.
that would be a cure for sure. Ha ha ha ha

I get the feeling like we've had this discussion before....



It's like deja vu all over again

Quote: Originally posted by BeamerBob

Jeff, I agree with you. Who gives a hoot. I'm thrilled that my buggy fits me well and has been able to handle every stress I've been able to throw at it without any failures of the metal or fabrication, all without me knowing what specific kind of metal it is made of, or even knowing much about words like "annealed" and "ductility". But I must say Pythagoras has always been my hero.

Bob, this only leaves me to wonder why you would think that you would have much to contribute to a discussion about the materials used in the fabrication of kite buggies and their properties.
However, I think you, as someone who could be riding a buggy built by one these guys, might be concerned when a supposedly knowledgable builder suggests post weld heat treating mild steel or over estimates the strength of a material by 500% because he does not understand what the numbers on the spec sheet mean.

Jeff, my guess the reason we did not discuss the non-ferous buggy materials: nobody brought them up, at least until you did. If you wish to spout fantasy facts about the other materials you spoke of, I will be glad to let people know when I think you are spouting crap.
I think you will find the articles I recommend at the top of the post apply to materials in general and not just ferrous metals.

Jeff, my guess the reason we did not discuss the non-ferous buggy materials: nobody brought them up, at least until you did. If you wish to spout fantasy facts about the other materials you spoke of, I will be glad to let people know when I think you are spouting crap.

Spounting fantasy facts? Who appointed you the metal police?
I guess at this point I need to set myself up as jury, judge, and executioner. Cause I have been called the biggest a** hole in the world.

Jeff, I don't know why you let that upset you this time. Can't be it hasn't happened a million times before. I bet everyone of the guys on the work site where you dropped the grinder eighty feet thought you were the most useless tool on earth. In Canada, the boss would have had your bum off that site before one of your co-workers killed you. Americans are obviously more tolerant of idiots than us.
S

It is in no way upseting to me, its part of the dialog that goes on and on. I dont take things on a personal level anymore, much like the idiot that thought his beat up crapalac was beyond being moved by my truck as he tried to push me through the gas station. Nothing a bit of elbow grease wont clean off my front bumper. A matter of perception, one mans crap is an idiots treasure.

With all that said, its obvious you dont know how government construction jobs are run let alone delt with. Not sure you would last in that atmosphere. Definitely different than Canada. Come to think about it, I hired 20 some Canadian Pipefitters for some work at Arco in Cherry Point. They were the last ones I hired and the first ones layed off, even though they were 4 dollars anhour cheaper than the US Pipefitters.

Love you Scudley, dont know who I could pick on if you never came down to Sunset. Might be better if I picked on beamer bob from now on, is that OK bobby?

Soliver, like the cartoon.
does sound a bit like this has happened before. How quickly we forget.:shocked2:

Scudley, we are going to Sunset the weekend after Christmas. You up for a bit of bugging?

Scud I guess why I posted was to point out that other guys have figured this out enough that the rest of us don't have to or don't care. It seems that as long as I don't own a Peter Lynn buggy or jump, the designers have done good enough for my buggies to exceed their design parameters and succeed at carrying out their intended purpose. You seem to be a hero coming to the rescue of a problem that no one cares about. But please carry on.

Jeff, I have worked at mines all over the Americas. Every job site I have been that involved high steel, dropping something was an unforgivable sin. It was pretty much if anything drops from up there, it had better be you. Knew a guy back in the eighties who dropped a hammer from ten stories on the Pan Pacific. His co-workers convinced him it would be much healthier if he worked elsewhere. They were so convincing, he moved to Toronto. Forgive me if I find your grinder story hard to believe.
The weather looks great for next week end, what are the tides like?
S

Scudley, unless you were there the day of the suicide, you really don't have a clue how it all turned out. At that point you really have no say.
Other than that, us americans dont care about any stinking tides, any day at the beach to buggy is a good day to be at the beach.

Quote: Originally posted by BeamerBob

Scud I guess why I posted was to point out that other guys have figured this out enough that the rest of us don't have to or don't care. It seems that as long as I don't own a Peter Lynn buggy or jump, the designers have done good enough for my buggies to exceed their design parameters and succeed at carrying out their intended purpose. You seem to be a hero coming to the rescue of a problem that no one about. But please carry on.

My apologies Bob, I did not realize that topics were restricted to those that interest you.
Again, I wonder why you feel compelled post that a topic is of no interest on topics that are of no interest. Is this a manifestation of OCD? Most people seem to express this feeling by moving on to the next topic not posting about their lack of interest. Your way seems like more work.

S

Scudley you should read back and notice that I only responded to something Jeff said until I was attacked by you. Once attacked I feel free to speak my mind without so much restraint.

Bob, I did read back. Do you feel I attached you by saying "Bob, you can free think as much as you want but no amount BS is not going to make annealed 304 stainless less ductile than annealed 1018 or make you able to make 1018 stronger by heat treatment. Free thinking is fine, but spouting BS is not free thinking, it is just spreading fertilizer."
If so, I think you are being overly sensitive, you never said either of the two statements in question, did you? No? then how was this an attaching you?
S

You seemed to be attacking someone (maybe me?) in reply to my post and while it didn't make much sense to me it was obviously not friendly. Your tone and self perception remind me of someone that got banned years ago. You're enjoying this much more than i am so I'm out.

Bob, nicely veiled threat. I suggest you read the other topic and see where the attach started.. I did not consider any of these discussions friendly. I thought it stopped being friendly when not only was my professional competence was called into question but the competence of my whole profession. Where did this all start? I had the gall to say another member was using the the incorrect value for strength. Where was your concern about the friendly tone then?
S