Adding an electric hoist to a 2-post lift?

[aka Larry]

I'm considering adding a hoist to my Atlas 9KOH 2-post lift. The main purpose would be to lift the hardtop on my Jeep, which only weighs about 120 lbs. The initial plan was to install the hoist in my attached garage, but it will be considerably more work to do so.

Yes, I realize the crossbar on my lift was not designed for a vertical load. It's pretty much there to bridge the gap between the posts and provide a route for the cables and hydraulic lines. No, I don't plan to attach the hoist to that.

I'd like to add a beam across the posts (steel or wood) to transfer the load. Can I do this safely? If so, approximately what size beam would I need to span the 10 feet and support a max load of 400 lbs in the center?

 

[nadogail]

For your intended purpose I would look for a used load beam from pallet racking. They are strong and I have found them to be inexpensive.

You can get a lot done with an angle grinder and a welder.

 

[ZX3ST]

I personally don't see a problem with it.

I've seen people use Unistrut for attaching light duty trolleys to their hoist. Look at Unistrut P5000? The beam loading table suggests it'll hold plenty for your application with very little deflection. You could even possibly attach to your ceiling trusses with lag bolts. With only a light load spread across 5-6 trusses, seems to me it'd work well.

https://unistrutohio.com/products/p5000t

 

[WhoWhatNow]

Why not just use the lift to remove the hardtop? Put a sling over a pair of arms and you are done.

 

[dante2]

I'm considering adding a hoist to my Atlas 9KOH 2-post lift. The main purpose would be to lift the hardtop on my Jeep, which only weighs about 120 lbs. The initial plan was to install the hoist in my attached garage, but it will be considerably more work to do so.

Yes, I realize the crossbar on my lift was not designed for a vertical load. It's pretty much there to bridge the gap between the posts and provide a route for the cables and hydraulic lines. No, I don't plan to attach the hoist to that.

I'd like to add a beam across the posts (steel or wood) to transfer the load. Can I do this safely? If so, approximately what size beam would I need to span the 10 feet and support a max load of 400 lbs in the center?

I've done it and it's working out good so far. I used .25 2x2 square tube. The hoist has square u bolts that allows it to slide to one side when not in use. So far I've left it in the middle and not hit a windshield yet.

 

[wssix99]

You can't fix both ends to the posts because they move when you are taking a normal load on the lift. If you are going to do this, you could pin one end and then make sure the other end slides freely in 4 directions.

 

[aka Larry]

You can't fix both ends to the posts because they move when you are taking a normal load on the lift. If you are going to do this, you could pin one end and then make sure the other end slides freely in 4 directions.

The crossbar on the top of the lift (that covers the cables and hoses) is fixed at both ends now, so how is this different?

 

[aka Larry]

I've done it and it's working out good so far. I used .25 2x2 square tube. The hoist has square u bolts that allows it to slide to one side when not in use. So far I've left it in the middle and not hit a windshield yet.

So at least I'm not totally off my rocker! Thanks for the pics!

 

[CraigStu]

I'd find a couple of well chosen, no knots etc, 2x10s, glue and screw then together and go with it. Be sure to attach them in a way that won't allow them to flip on their side as load increases/

 

[gregs]

I have always wanted to add a beam strong enough to pull a engine with. I have a 2 ton chain fall I could use. Just havent come across a beam I thought would work yet.

 

[aka Larry]

I have always wanted to add a beam strong enough to pull a engine with. I have a 2 ton chain fall I could use. Just havent come across a beam I thought would work yet.

I assume you don't have a lift? If you do, I have found it's much easier to raise the vehicle and drop the engine out the bottom.

 

[gregs]

I assume you don't have a lift? If you do, I have found it's much easier to raise the vehicle and drop the engine out the bottom.

I have a 2 post lift. I would be referencing a older rear drive vehicle without a removable front cross member. I have a transmission jack so that makes it easy to drop out a transmission if needed. I have borrowed a engine hoist before, which is probably the easiest way still and probably cheaper than finding a beam.

 

[Bad Habit]

I assume you don't have a lift? If you do, I have found it's much easier to raise the vehicle and drop the engine out the bottom.

Well, that all depends on the vehicle. Pretty sure the Silverado I have would require a lot of frame cutting to do that

 

[aka Larry]

Well, that all depends on the vehicle. Pretty sure the Silverado I have would require a lot of frame cutting to do that

True. The engine swaps done on my lift have all been done on my FWD race car, where the front subframe just drops out.

 

[OccupantRJ]

I have always wanted to add a beam strong enough to pull a engine with. I have a 2 ton chain fall I could use. Just havent come across a beam I thought would work yet.

Years ago back in the dinosaur age I had two utility poles sunk into the ground about 8 feet apart with a piece of 1/4” wall 2x4 steel tubing across it in vertical orientation that I pulled engines and loaded and unloaded heavy objects with for years. It was attached to the top of the posts with two 1/2” lag bolts 10” long.

 

[aka Larry]

My buddy has this gantry setup from HF and it works pretty well. Not that cheap, but I could see it being worth it after a couple of uses.

 

[dante2]

So at least I'm not totally off my rocker! Thanks for the pics!

You're welcome. I've only used it twice now, top on last year and back off last month. Still trying to get the balance just right on the straps.

 

[wssix99]

The crossbar on the top of the lift (that covers the cables and hoses) is fixed at both ends now, so how is this different?

The top crossbar is weak and bends like a bow when the posts move. (You don't want this for a solid member that is going to take weight.) With a solid member, you need to have one fixed attachment and one moveable. Every bridge you drive over with your car is built the same way. One end is solidly pinned...



and the other end of each span is moveable on a roller or rocker bearing...

 

[Beemer]

Perhaps another idea.
When we had a removable top wrangler I put a unistrut trolley rail mounted to the ceiling framing and bought one of their trolley's (manual).
I just used a light block and tackle hung off the trolley.
Once the top was hung I could push it across the room to it's storage spot.
Jeep is gone but the trolley remains. Its a portable bicycle storage device now.

 

[cosmokenney]

I've done it and it's working out good so far. I used .25 2x2 square tube. The hoist has square u bolts that allows it to slide to one side when not in use. So far I've left it in the middle and not hit a windshield yet.

Is that red bed liner??

 

[olytdi]

I'm considering adding a hoist to my Atlas 9KOH 2-post lift. The main purpose would be to lift the hardtop on my Jeep, which only weighs about 120 lbs. The initial plan was to install the hoist in my attached garage, but it will be considerably more work to do so.

Yes, I realize the crossbar on my lift was not designed for a vertical load. It's pretty much there to bridge the gap between the posts and provide a route for the cables and hydraulic lines. No, I don't plan to attach the hoist to that.

I'd like to add a beam across the posts (steel or wood) to transfer the load. Can I do this safely? If so, approximately what size beam would I need to span the 10 feet and support a max load of 400 lbs in the center?

Clearly I don't fully understand what you're attempting to do here. I have a Silverado with a hard topper/canopy/cap over the bed. When I want to remove it, I use my 2 post lift to raise some beams I made out of 2x6 and plywood that are placed between the canopy and the truck rails. Lifts the canopy off and I can drive out from underneath.

Granted, if I want to then move and store the canopy, I get my tractor with forks and move it wherever it needs to go. Usually, I remove the canopy only temporarily for a specific task where the canopy needs to come off. Then I just drive back under and re-attach.

In other words, I use the lift arms to remove the canopy. Why not use them on your lift?

 

[Natty Bumppo]

Why not just use the lift to remove the hardtop? Put a sling over a pair of arms and you are done.

Had the same question?

I used to use my lift to remove the top on my K5 and I would store it raised all summer. But that meant my lift was out of service all summer. Then I rigged up a hoist with some pulleys, rope, Unistrut, and a $100 electric winch from HF.

 

[dante2]

Is that red bed liner??

Yes it's over 9 years old in that pic. Currently stripping it off to change colors.

 

[aka Larry]

My current plan is to install a section of uni-strut across two of my roof trusses and use a trolley to suspend the electric hoist. This should put the hoist out of the way of vehicles on the lift, and also provide a place/method for unloading heavy/bulky items out of a truck bed.

I'm going to pick up the strut today, and I have the trolley on order. Should be able to get most of it done this weekend, depending on how I motivated I am with the weather. Supposed to be almost 100 here on Saturday.

Thanks to everyone for your thoughts and suggestions.

 

[cosmokenney]

Yes it's over 9 years old in that pic. Currently stripping it off to change colors.

Ooofff... stripping bed liner is a pain. I have a half finished aluminum tread plate that I'm stripping to make a cargo area cover for my JL Wrangler. The guy I got the tread plate from gave it to me free. But he rolled the bed liner on right over the polished surface. So it peels off in some spots but I need to wire wheel it in others.

 

[dante2]

I'm using Citrus Strip. Apply it, cover with plastic sheet, and let it sit overnight. It peels off real easy after that.

 

[aka Larry]

Here's the update on this project.

I talked to a buddy about adding a beam across the top of my lift and he said "Why don't just use the roof trusses to support the beam"? The more I thought about it, that made sense, so off in that direction I went.

I decide to span three trusses (mine are made from 2x2 steel tubing) using a 10' piece of Uni-strut for the beam. Since Uni-strut is already made to use a trolley, I thought I could use one and make the hoist somewhat mobile for use lifting other things in the shop.

I built three brackets from 2"x2" steel angle and 1/8"x3" flat bar to sandwich each truss, and through-bolt them in place. The Uni-strut is suspended for the brackets using 1/2" all-thread so I had some adjustment to make the track level. It was kind of precarious working alone on a 12' ladder, but I was careful and got it done.

Here's where it stands as of last night. I'm planning to get the wiring done tonight and hopefully get the hoist in place and working. Stay tuned...

 

[dante2]

Here's the update on this project.

I talked to a buddy about adding a beam across the top of my lift and he said "Why don't just use the roof trusses to support the beam"? The more I thought about it, that made sense, so off in that direction I went.

I decide to span three trusses (mine are made from 2x2 steel tubing) using a 10' piece of Uni-strut for the beam. Since Uni-strut is already made to use a trolley, I thought I could use one and make the hoist somewhat mobile for use lifting other things in the shop.

I built three brackets from 2"x2" steel angle and 1/8"x3" flat bar to sandwich each truss, and through-bolt them in place. The Uni-strut is suspended for the brackets using 1/2" all-thread so I had some adjustment to make the track level. It was kind of precarious working alone on a 12' ladder, but I was careful and got it done.

Here's where it stands as of last night. I'm planning to get the wiring done tonight and hopefully get the hoist in place and working. Stay tuned...

Looks good. I have the same type of building and I'm curious how much weight the structure can handle even spread out like that. Do you have roll up doors in your building?

 

[aka Larry]

Looks good. I have the same type of building and I'm curious how much weight the structure can handle even spread out like that. Do you have roll up doors in your building?

Max load on the hoist in only 440lbs, which I doubt I'll ever get close to, but I'm confident the dual-tube truss design can handle more than the hoist.

Yes, I have three roll up doors.

 

[racecougar]

Be mindful that that unistrut isn't rigid enough to prevent notable point loading on whichever vertical tie (and truss) you position the hoist nearest to. You will have nowhere near equal load distribution across the three verticals. The flat tie plates and angles sans gussets are a concern as well.

It's likely fine for the 120 lb hard top, but I don't know that I'd try to hit that 440 lb loading value.

 

[aka Larry]

Be mindful that that unistrut isn't rigid enough to prevent notable point loading on whichever vertical tie (and truss) you position the hoist nearest to. You will have nowhere near equal load distribution across the three verticals. The flat tie plates and angles sans gussets are a concern as well.

It's likely fine for the 120 lb hard top, but I don't know that I'd try to hit that 440 lb loading value.

Are you saying the deflection is too much for the Unistrut or too much for the truss? The Unistrut is listed at being rated for 680lbs (uniform load) across a 60" span.

 

[racecougar]

The unistrut is not rigid enough to evenly distribute the loading to the three points you've attached it to. The load path will be heavily biased to the nearest vertical attachment/truss.

Regarding the unistrut rating, that goes out the window with the loading arrangement you're utilizing here (point load of hoist trolley and only three mountings).

 

[aka Larry]

The unistrut is not rigid enough to evenly distribute the loading to the three points you've attached it to. The load path will be heavily biased to the nearest vertical attachment/truss.

Regarding the unistrut rating, that goes out the window with the loading arrangement you're utilizing here (point load of hoist trolley and only three mountings).

I see what you are saying, and thank you for your input. Could I increase the rigidity of the Unistrut by adding to the cross sectional area? Maybe by adding a piece of steel angle or square tube on top?

Like you said, I'm sure this wont' be an issue, with the 120lb hard top, but I'd like to be able to lift closer to the hoist capacity.

 

[racecougar]

Adding T-bar or angle to the top of the unistrut will increase its rigidity to an extent and assist in load distribution to your mountings; the greater the vertical height of the angle, the better here. That said, keeping things practical here (not building a full-on unistrut truss), I'd work to make your hoist trolley as wide-spanning as possible, with the caveat that that will reduce the total side-to-side movement allowed.

 

[gearhead1]

It can be safely done.

My thought process:
If the unistrut or other manufacturer has an online calculator, use that.

Otherwise, you need to know the cross section dimensions, and material of the beam, and span (you mentioned 10 feet) in order to calculate how much the beam can hold. A beam can be selected based of this. Alternatively, if you have something already (a channel, I-beam, square tubing, etc) you can calculate how much it will hold. A lot of times the exact material is not known, but there are ways around that.

Generically, the strength of the beam comes from how much material you can locate away from the neutral axis.

Going the unistrut route on the trusses:
Racecougar is right. The load could be situated such that all of it is going in one truss. I agree, likely fine for 120lbs. The rule of thumb I use, is determine if it would hold me. Could I jump up and down if I was on top of that truss on the roof. Or if there was a pull-up bar attached to that truss near the peak inside the building, could I pull myself up without bending the truss.

I suspect the span between the unistrut supports (span between trusses) would be the limiting factor. What is the span between trusses?

SIDE NOTE FOR POSTERITY (people search these threads years later - maybe it helps someone):
2-post lift columns: Absolutely not being a smart aleck, but obviously the columns hold a vehicle, so no issue there. Logically, there is plenty of margin. The only issue is how big of beam you need. (Technically if you really want to know, short columns fail by crushing and long columns fail due to buckling. To calculate, you first determine if is a long column or short column, the use the Johnson formula for a short column and Euler formula for a long column. The column analysis is moot as we know the lift holds vehicles.)

Trusses: It is more difficult to know exactly how much they can hold. Without knowing material type and thickness. However, there are telltale signs that you could tell the loading is too high. One would be put set a dial indicator on a ladder and measure deflection. Generally structural Steel bends long before it breaks. Of course spreading out the load on multiple trusses reduces the stress in each individual truss.

 

[aka Larry]

I suspect the span between the unistrut supports (span between trusses) would be the limiting factor. What is the span between trusses?

60" between trusses.

 

[dante2]

I'm not to hip on all things structural but would eliminating the threaded rod between your plate and the unistrut help any in the load bearing area? Will that whole thing not flex some once you have weight on it?

 

[beatuptruck]

My opinion:
Put a 440lb load in the center of a 60", 12 gauge/1 -5/8" tall? unistrut span. The unitrut could buckle/spread open allowing the trolley/load to plummet to the ground. This is what will fail first.