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Old 03-07-2019, 03:24 PM
mikeysp mikeysp is offline
Join Date: Mar 2019
Location: Nashville, TN, USA
Posts: 7
Default Beginner wanting to learn how to design steel structural requirments

Howdy, I am new here and glad I found such a forum.

I want to learn some better way to calculate and design steel beams, posts, trusses for projects. I am working on a design now to lift 5K + pounds of weight (log) and I am trying to design in a way that is lightweight, so this question popped up again,

"how do I come up with the layout style (Big beam vs Truss vs?) and what shape and size tubing do I use?"

While it is nice to have folks help me by solving it, I would really like to be able to make some headway myself. I know there are a huge amount of variables, but surely there must be some basic design parameters that will keep me from using 1/4" wall when 14 gauge will work? Because without any understanding, I am just throwing material at it.

I have welded a few dozen projects together over the last several years. I tend to throw a heavy piece of steel that "ought to work" and this usually equates "P" for plenty, or really over engineering, or guessineering as I do not know.

While I expect to add some extra steel to a structural problem, I hate the fact that I am just faking it.

Can anyone point me in the right direction for a beginners guide to steel math that would help me solve my current problem and aid me in the future?

Below is a pic of concepts I am trying to solve for:

Thank you.

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Last edited by mikeysp; 03-07-2019 at 08:15 PM. Reason: I removed third party photo hosting link.
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Old 03-07-2019, 04:50 PM
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Scotts Scotts is offline
Stuff, Just stuff
Join Date: Dec 2004
Location: Wichita Kansas
Posts: 5,086

Hello Mike,

Glad you found us.

If you would please review FAQ About the pictures. You have a few hours to fix if you are able. Nice pictures so we would like to keep them if possible.

I am not one to draw and figure this kind of stuff. There are people on here that are.

In the mean time search Beam Boy on here and it may help you with your questions as well.

Thanks for stepping into the forum.

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Old 03-07-2019, 05:20 PM
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arizonian arizonian is offline
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Join Date: Jul 2007
Location: Tucson, Arizona
Posts: 1,202

Math is your friend. The more mathematical background you have, the less you will struggle.

For an overall way to design structures: D=Z4R2DPNF47ZGJ68JXEDD

For welding, Blodgett's Design of Welded Structures

It's not going to be easy unless you already have some engineering type classes under your belt.
Bill in sunny Tucson

I believe in gun control.

Gun Control: The ability to consistently hit what you are aiming at.

Weldor by choice, engineer by necessity.
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Old 03-07-2019, 08:19 PM
JBFab JBFab is offline
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Join Date: Oct 2006
Location: NorthCentral Wisconsin
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Both books arizonian mentioned are excellent. There really isn't a magic bullet so to speak. Trusses take more time to engineer because there are more calculations to do.

As previously mentioned beam boy is a nice little program, but it isn't the solution. It's nice for finding out how much deflection and stress you will have (come to think of it that's all it really does), but it doesn't cover axial loading and it certainly doesn't give you a pass or fail - it is just a tool.

The real meat and potatoes is having a good understanding of how forces will act upon the member and understanding what the limiting states might be.

Sent from my SM-N960U using ShopFloorTalk mobile app
I believe the appropriate metaphor here involves a river of excrement and a Native American water vessel without any means of propulsion.
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Old 03-07-2019, 08:20 PM
mikeysp mikeysp is offline
Join Date: Mar 2019
Location: Nashville, TN, USA
Posts: 7

Thank you gents. I fixed my photo posting error. I appreciate the links and will check them out. I am glad I found you guys.

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Old 03-07-2019, 08:47 PM
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milomilo milomilo is offline
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Always keep in mind that you will need to consider a safety factor, i.e., never design to max load on any portion of a structure.

We are losing sight of civility in government and politics. Debate and dialogue is taking a back seat to the politics of destruction and anger and control. Dogma has replaced thoughtful discussion between people of differing views.
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Old 03-08-2019, 12:14 AM
mikeysp mikeysp is offline
Join Date: Mar 2019
Location: Nashville, TN, USA
Posts: 7

Agreed. I think that spirit of throwing metal at it will still pervade, but to a lesser degree. and with less guessing. x is good enough, add y% safety margin for such an application.

Thank you.

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Old 03-08-2019, 02:19 AM
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GWIZ GWIZ is offline
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Posts: 6,736

Does this link help you?
The factory of the future will have only two employees, a man and a dog. The man will be there to feed the dog. The dog will be there to keep the man from touching the equipment. ~Warren G. Bennis
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Old 03-08-2019, 07:38 AM
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digger doug digger doug is offline
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Location: NW Pa
Posts: 11,533

"Strength of Materials" there are many books

Or the machinist Handbook has a very nice section.

Also seek out the Lincoln electric foundation book "Design of Weldments"
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Old 03-08-2019, 09:25 AM
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randydupree randydupree is offline
Why, Hell Yes!
Join Date: Aug 2005
Location: Bainbridge Ga
Posts: 5,985

I'm going to say most of the guys here have built lots of stuff and never looked at any drawings or anything else.
They did pay attention to gantry cranes,wreckers,truck cranes,home made contraptions and swing sets modded to pull engines etc.
Tree limbs that were too small had a board shoring up the limb.
The board was small too,in most cases.

My advice,pay attention to everything,you will see failed creations and you will learn from that.
You will see overbuilt stuff too.
But mostly you will see things built out of whatever we had laying around,most of us never had the money to buy new steel,we stole,scrapped,traded and did whatever we could do to build what we needed.

Everyday i see something thats being built and i say "that will never work!"
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