Unique boom pole design

[texbaylea]

I was viewing another forum and spotted this

Two recent projects: Boom pole and steel table - The Home Shop Machinist & Machinist's Workshop BBS

Thought some TBNers might be interested. Looks very well done.

Vernon

 

[ragkar]

That is an interesting design. I made one recently for my bucket using a trailer receiver and I used square steel a bit lighter than 1/4 inch. I don't know yet how much I can lift with that.

 

[bobodu]

Made this just this morning. Sometimes my forks won't reach to the middle of my dump bed...

 

[tessiers]

I have a bale spear that goes on my JD quick atachment and I have a 12' piece of 2 1/2" steel pipe that slides over the main spear. I have used it to do many things including setting the 30' trusses on my brothers garage. It can reach 17' high. Works great for me.

 

[RonMar]

Nice boom on the link, I think I would have used round tube instead of the box on edge for the boom(same strength, less weight), but overall a good cantelever and triangulation layout...

 

[gpflepsen]

Made this just this morning. Sometimes my forks won't reach to the middle of my dump bed...

I'm not saying the OP's subject post did anything wrong, but the square tube will see ~30% more stress if set on a 45ｰ angle. The post quoted above pictures a tube mounted to perform better and will lift with a lower stress, given the same loading.

 

[Renze]

I'm not saying the OP's subject post did anything wrong, but the square tube will see ~30% more stress if set on a 45ｰ angle. The post quoted above pictures a tube mounted to perform better and will lift with a lower stress, given the same loading.

At a previous job of mine, they used to build feeders. The cutting board to fill the bin, was suspended on two tubes mounted on a 45 degree angle, which telescoped into each other.
They said the tube was stronger when used this way... I actually doubt BOTH claims, but cannot find any data in my engineering almanak to back this up.

 

[mrcaptainbob]

Nope. I don't believe it would be stronger at the 45* angle. Any loading would be a point load causing concentration and a crushing force on the top of the wall edges at the apex. Keeping it 'square' causes the load to be distributed on the vertical side walls. Puts the top of them in compression, the bottom in tension. The top of the side walls is stabilized and strengthened by the the top of the box. So too with the bottom of the side walls being strengthened by the bottom. Similar to the concept of I-beam. The top and bottom flanges are what stabilizes and strengthens the center web.

 

[Peej]

captain bob, I've a question. I'm planning on building a hitch hauler gizzmo out of a P/U receiver hitch. I like the versatility of slide in accessories.
I came across a "Handi Hitch with telescoping boom pole" on ebay.
I really like the Idea. Question -when drilling a hole in tubing for this application is it better to go from side to side or top to bottom? Any help will be appreciated. ( Could not figure out how to transfer the Pic of the Hitch/pole)

 

[Scotty370]

PeeJ-I'm going to jump in here 'til the Capt' gets back, and say that the connection pins should definately go in thru the sides. Witness an Engine Hoist. The lifting causes the top surface of a (say) 2 X 2 rectangle to be in tension, while the bottom, is in compression! Think of what would happen if you were to hack saw across either surface, while lifting? The top would 'open', while the bottom cut would bind your saw blade. The side act only to keep things in alignment, and while any hole in any surface will compromise strength, your sacrificing less, going thru the sides. ~Scotty

 

[jenkinsph]

PeeJ, I agree on the horizontal pin as Scotty reasons. What I have done with hitch parts that are drilled through is install a heavy duty bushing with the proper 5/8" bore, weld it in place to prevent the wall from tearing.


Steve

 

[Stumppuller]

Since there is a top-mounted tension bar, it doesn't much matter whether the tube is assembled at a 45 or not. What it does do, however is provide a well presented surface for the two stabilizer rod weldments. I say a big thumbs up on this clean design.

 

[MJPetersen]

the connection pins should definitely go in thru the sides. ...The side act only to keep things in alignment, and while any hole in any surface will compromise strength, your sacrificing less, going thru the sides. ~Scotty

A second on that. It is going to be weakened significantly by a hole in the side only if that hole extends to the top or bottom. As long as there is a web above and below the hole the strength is compromised very little. That is where holes on structural items are always put to lighten the structure without loosing strength. Gradeall boom, aircraft spars, and truss applications are all examples.

Additionally, by putting the square tubing at a 45 degree angle severely weakens it. I did some experimenting once on square tube and it always failed at a 45 degree angle. the load swung left or right and the tube collapsed in that direction. it did not bend straight, it always bent one way or the other.

Mike

 

[J_J]

Here is a picture of a boom pole that I modified to work on my Power-Trac. It can still work on the 3 pt. It also has square hitch tube welded on the end for using different plug in', or extensions.

 

[Peej]

Thanks guys, this site is the greatest for info.
will try to get to the build after the 4th. I'll try to post pics.

 

[rdbrumfield]

I have had this loader extension for a few years. Made it out of 11/2 in pipe. It just locks into the cross frame i put on the loader. No pins or bolts.

What I have hanging is my quad and some tools. When I took it for shipping it was a bit over 1250lbs. I was surprised at that. Sending it to Anchorage as I am living near there now.

Normally I have a small pulley at the end of it, but it was on another piece of equipment at my shop. So I didn't dare winch the line in across the shackle.

 

[mrcaptainbob]

Good reply to Peej, Scotty. I also like Jenkinsph suggestion of doubling up around the hole. To be clear, however, the square tube at a 45* is strong and can support quite a load. It's failure is just at a lower load than if that same tube were square with the world. As long as it's not taxed beyond it's capacity, it should work fine. Of coarse, that's why I'm always repairing my stuff....