- #1
parkland
- 60
- 3
- TL;DR Summary
- Potential project/ learning about steel strength
Hi all,
I was hoping a guy with limited engineering skills might find a little help and understanding...
I'm not formally trained but am somewhat mechanically inclined. I build things, and usually have good luck estimating strengths and designing things without doing the math or science behind it.
That being said, here is my story...
A little while back, me and my friend started talking about starting a little tree limbing business. We wanted to buy an old telehandler, manlift, or bucket lift system and install an electric chain saw at the end so we can cut limbs from the ground. (Thus not requiring xray inspections for human riders, and inherently safer.)
So we started looking at equipment, quickly ruled out telehandlers as the boom is fixed to the body, meaning that you'd have to drive to pivot the boom.
We think man lifts would be the best in theory, but they are super heavy and would need a semi truck and trailer to pull around.
That leaves us with bucket boom trucks. They seem to be available and relatively inexpensive, but there is still issues...
First of all, seeing as they were designed to move people around, the hydraulic system must have a very small pump meant for slow actions. I suspect it's not just a small pump but small lines and controls as well.
Also, from what we've seen so far, it is very hard to find a used for sale unit with long reach. Most are around 45 ft, and that isn't enough to limb high trees.
So what I'm getting at slowly here, is that we started discussing if it would be reasonable to build our own boom system?
It's not exactly a high tech design, but we can't just take an existing design and make it bigger as we don't know the grade of steel used in these booms.
Am I correct in thinking that if steel is 40,000psi strength, you can apply 40,000psi to a 1x1x1 cube and it would never become permanently deformed from that? And the same for tensile strength?
How would a boom be designed for something like this? If we have a 40ft long box beam, 3x8 inches and 1/4 inch wall thickness, and the hydraulic ram is attached 5 ft from the fixed end of the boom, how are the stresses calculated? Looking at the cross section of the beam, 3x8 1/4 wall , do we figure out the compressive strength of the bottom half and tensile strength for the top half, and add safety factor to that?
I just want to figure out how that works. I could keep blabbing but I'll wait and see if I'm blabbing in the wrong direction first.
I was hoping a guy with limited engineering skills might find a little help and understanding...
I'm not formally trained but am somewhat mechanically inclined. I build things, and usually have good luck estimating strengths and designing things without doing the math or science behind it.
That being said, here is my story...
A little while back, me and my friend started talking about starting a little tree limbing business. We wanted to buy an old telehandler, manlift, or bucket lift system and install an electric chain saw at the end so we can cut limbs from the ground. (Thus not requiring xray inspections for human riders, and inherently safer.)
So we started looking at equipment, quickly ruled out telehandlers as the boom is fixed to the body, meaning that you'd have to drive to pivot the boom.
We think man lifts would be the best in theory, but they are super heavy and would need a semi truck and trailer to pull around.
That leaves us with bucket boom trucks. They seem to be available and relatively inexpensive, but there is still issues...
First of all, seeing as they were designed to move people around, the hydraulic system must have a very small pump meant for slow actions. I suspect it's not just a small pump but small lines and controls as well.
Also, from what we've seen so far, it is very hard to find a used for sale unit with long reach. Most are around 45 ft, and that isn't enough to limb high trees.
So what I'm getting at slowly here, is that we started discussing if it would be reasonable to build our own boom system?
It's not exactly a high tech design, but we can't just take an existing design and make it bigger as we don't know the grade of steel used in these booms.
Am I correct in thinking that if steel is 40,000psi strength, you can apply 40,000psi to a 1x1x1 cube and it would never become permanently deformed from that? And the same for tensile strength?
How would a boom be designed for something like this? If we have a 40ft long box beam, 3x8 inches and 1/4 inch wall thickness, and the hydraulic ram is attached 5 ft from the fixed end of the boom, how are the stresses calculated? Looking at the cross section of the beam, 3x8 1/4 wall , do we figure out the compressive strength of the bottom half and tensile strength for the top half, and add safety factor to that?
I just want to figure out how that works. I could keep blabbing but I'll wait and see if I'm blabbing in the wrong direction first.