Engine crane leg angle design question

[Bill D]

I have noticed all the cheap engine cranes use a similar leg design. They have the legs splayed out at an angle of roughly 10 degrees from center. I have not actually measured the angle but the pictures all seem to be the same angle. Why was this angle chosen?
Or was it the first one was made this way and everyone just copied it. My OTC crane has three possible leg splay angles so they feel there is some reason for more then a fixed spacing.

I realize wider spacing is more stable but requires longer legs to be far enough beyound the lift hook point. The narrow spacing can get inside of tires etc while the widest spacing can go outside obstructions. I believe my OTC is wider at the fixed end then most so the narrow spacing is still stable enough for most work.
I could not find a good picture but the OTC legs are hinged to the frame at the back and pinned under a cross beam at one of three positions when in the working position.
Bill D

 

[Bill D]

I understand the best angle for long range rifle or artilley fire is about 27.5 degrees not the 45 degrees that would be true without air resistance and possible aerodynamic lift to the bullet.
Bill D

 

[john.k]

All the crap Chinese cranes are pictured lifting a 2 ton weight.....in actual they may lift 1/2 ton,but the cheap nasty castors will collapse under that weight .......I got a good Chinee crane from a tool place about twenty years ago,and decided to get another online during the lockdown........what an appalling POS.....the picture on Kogan website was a bait and switch ,the crane was just garbage............Kogan has hopes of becoming another Amazon,unfortunately all their "fulfillment partners' are tricksters............no wonder their stock price has tanked.

 

[metalmagpie]

The hardest question is always "why did they build it this way?"

I suspect the answer has to do with fitting into a box.

My Ruger shop crane has widespread parallel legs which can be splayed out wider.

 

[JoeE.]

So it will fit between the wheels of a car when you slide it in to lift up the engine....

 

[tailstock4]

The yellow crane in these pictures started off life as a cheap engine lift from O’Reilly’s Auto Parts. Little remains unmodified from that original lift. It has been strengthened in almost every way including in some that you can’t see. It has a 1,500 lb. hoist with a load brake which means no ratchet to fool with. It has a hand wheel I made on a ring roller out of ½” pipe. It weighs about 1,150 lbs. Fully extended, it will lift about 1,200 lbs.

The crane sits on a trolley that can be moved front to back on the legs, but this is a feature that I seldom use.

The smaller crane is just a hodge podge of things I had laying around. The crane on it was made for the back of a tractor on a 3-point hitch, but I decided that in the end this configuration was more useful. It uses the same winch as the other. The frame is an old hydraulic table. The counterweight is a 45 kva boost transformer that is still usable. Behind that is a Monarch 10EE modular transformer. Below that is an 8” pipe filled with concrete. Fully extended it will lift about 550 lbs. It can get about anywhere in the shop, and I use it to change the chucks on the Pacemaker lathe or load heavy parts on to machines.

The thing about theses cranes is to get the pushing-it-around to what-it-can-lift ratio right. The more counterweight, it will lift more but is harder to move and maneuver. After about 20 years, I have these two about right for me. Anyway, I find these two cranes very useful.