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I have a junk Skyhook I rebuilt and use on my BP. I thought about making a mount for my BXA toolpost but like Charles said the thought of putting it on the toolpost makes me cringe.
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What do you use for lifting heavy objects?
- Thread starter Ecosta777
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I should have been a little more subtle in my choice of words. If that works for him, that's all that counts.
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I like the "dual purpose" nature of that.
Clever!
I may have to borrow that idea!
Brian
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I think it's mounted to the carriage to make use of being able to walk the chuck back off the mount. My thought was if something fails it's going to do a lot of damage to the lathe and him.
I just throw plywood over my rubbermade shop cart and back up to one bench, chevy and prise the thing on there and roll it off. the trick is a couple pieces on plywood and finding the tipping point. I use small dia pvc pipe to roll under the plywood. Before I "remodeled" I had a 6x4 exposed beam with a 4 sheave block and tackle that can do amazing service. I machinist pry bar, heel bar, Johnson bar. heeled dollies is something I'd like to find one day- a 6 foot heeled bar - some have wheels. The Hoyer lift ... expensive. I've been thinking of bolting a couple sistered 2x4's into a tee-pee with a matching base (4x4) - so it can easily be stored away. i'd need to fabricate the top piece or crown that accepts the three uprights from steel. hang a hook from the top on a pulley attached to a come a long. you'll hear it creak before it kills ya. ;-)
Needed to pick up the deck on the church’s tractor that I’m servicing to get access to the blades. Side benefit is it gave me a much better position for welding a crack on the front right gauge wheel support.
The Unitrac/Superstrut hoist trolley is smooth as glass and I still cannot believe how little it cost to install it.
Rick “300 pounds and not breathing hard” Denney
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- Nov 1, 2022
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that construction looks similar to my garage: prefab trusses of 2x10’s scabbed end to end. Ive considered a trolley system like that, but not sure how much weight I’m comfortable lifting with it. Do you have any concerns, what are you figuring is the max capacity?
The trusses in my shop are 2x12 on the bottom chord, but are box trusses to create a room upstairs. The T&G chipboard on the top side of those bottom truss elements is the floor of that room. That floor is rated at 40 pounds/square foot for full residential code. Had they used conventional W trusses, they would have only needed a truss every 8 feet just to support the metal roof. And the strut is mounted close to the wall of the upstairs room, where the trusses are effectively tied together stiffly by the wall materials.
With all that said, I think six struts supporting that strut should be good for loads rated in tons, much more than the hoist itself.
For the hoist itself, here's the dumba$$ engineering answer, because I am an engineer and I can't help it:
The P1000 Unistrut (and Superstrut if it is also 12-gauge steel like the P1000) is rated for allowable uniform loads between 24" supports of 1690 pounds. This number includes a safety factor, but it's a uniform load and it assumes the supports at 24" are effectively stiff against torsion. With the usual open-C hangers, I'm figuring an unbraced length factor of 0.8. And for a point load in the middle of the span, I'm reducing the allowable load by half per Unistrut's design guide. The strut that I bought has mounting slots in the flange, and Unistrut derates the load to 85% in that case. So, 1690 x 0.85 x 0.8 x 0.5 = 575 pounds at a point in the middle of each 24" span (all other locations would be higher). Now, that trolley hangs from the truss on two axles, so the 50% point-load reduction is too conservative--that reduction would apply if the load was hanging from a single piece of threaded rod through one of the slots on the flange. The axles on that trolley are about four inches apart, however, and this spreads the load enough to minimize point buckling and allows a greater load.
Unistrut rates the trolley at 600 pounds static and 300 pounds dynamic. A dynamic load would be a fast-moving load that can swing, not the careful easing it along the track the way most of us would do it. It might also apply to a sudden load, but with a chain hoist, sudden loads are hard to create unless your arms are a lot faster than mine, or you drop something that is caught by the hoist. But the rating of the trolley suggests to me that Unistrut expects typical installations of struts across 24"-spaced ceiling joists--the trolley closely matches the truss at its worst loading point.
The payload has to subtract the weight of the hoist itself, which in my case is about 50 pounds using the Armstrong Estimation Method determined when carrying the box into the shop.
The c-supports are lagged into the bottoms of the trusses using 3/8" hex-head lag screws 4" long. The screws themselves are far stronger than the threads in the wood, which is rated conservatively at 200 pounds per inch of thread engagement (that number assumes weaker wood than used in these trusses). The bolts have three inches of threads, so each lag screw should hold 600 pounds, or the entire load of the trolley. Of course, the load is distributed along the length of the strut.
TLDR: a quarter ton.
Rick "chucks, yes; mower decks, yes; engines, yes (well, maybe not the 455 in the motorhome with the transmission and final drive attach); cabinet saw, yes; lathe, no; tractors, no" Denney
My lathe's manual specifies maximum allowable force acting on the tool to be 600kg(1300lbs). It's a medium size lathe (16'' x 40'') made in the 1960 in Eastern EU. Back then the max force was used to calculate what cut the lathe can make etc so it was specified in machine manuals.
600kg(1300lbs) sounds like a lot, but I too would feel uneasy applying that kind of weight. Thankfully a lathe that can handle a piece of stock that big will probably have a tool post that can handle forces many times more.
As tools I use to lift stuff I started by buying a 3ton engine hoist. I discovered very quickly how difficult it is to manouver and like another person said it needs to straddle the machine to lift stuff off the bed.
So I've built an A crane. I guess you could call it a gantry crane, but the gantry is simply two pieces of steel plate with few bolts and two bearings as rollers riding on an 80mm(about 3in) I beam.
The piece of rope going through the ceiling is an alternate lifting method
I usually attach a chain winch and it's being used like this: (the shaping head is being lifted onto a table in front of it).
I decided to mount the I beam on swivels and use weld stops to both A frames preventing them from aligning sideways and falling down. Then I had to cut those stops off from one side because it made it so much more difficult to manouver.
In general I'm happy with it, but there is a number of things I would improve if I was making it again.
1- Caster wheels. I couldn't use actual casters, I used normal wheels. When they align well it's great, but they seem to like aligning sideways as frequently. I've made 4 rods that hold them parallel to each other. I should've used better quality wheels with an option to lock them in position.
2- I should've made it so the i beam can extend past the A frame.
3 - A better (shorter) and an electric winch. It is pretty slow to move anything with it.
Despite those shortcomings it works for me
