three post snowmobile lift system

[andyvh1959]

I'm building my 24x28 motorcycle shop garage. Its enclosed now, but not done. Space is always a premium, so vertical storage (off the floor) is always the best solution. I'm thinking of a lift/storage platform in the back corner of the garage that can do a snowmobile (summer storage) or motorcycles (winter storage) in the range of 1000 to 1200 pounds capacity. I have a bunch of motorcycles and the lighter ones (dirt bike, ice bike, project bikes) are smaller and lighter. My street bikes would still be on the floor of the garage.

Many systems exist, but I prefer a simple system that once the item is up and stored the area below is open. So I'm planning a three legged guide rail system using vertical C-Channel posts that contain guide rollers attached the platform on which the snowmobile rests. The three posts would be attached to the walls, two on one wall (the long side of the platform) and one on the end wall (the outer corner of the platform). All four corners of the platform would be attached by cables over pulleys to a winch and cable drums to lift/lower the platform. The winch would be located at one of the posts on the long side of the platform. During lifting or lowering, all four corners of the platform are carried by the cables.

When the platform is in use, the four corner cables over pulleys would lift the loaded platform to the storage height. At the stored position, I’d engage a lock system so the loaded platform is held in place, and the vertical load is on the three posts. The remaining “open” corner with no post, would be connected to the ceiling truss by a cable, chain or strut to the eyelet installed into the truss. Doing this, based on a platform load of 1200 pounds, each corner post would support 400 pounds, and the one open corner would be connected to the roof truss, a load of 400 pounds. When the platform is down on the garage floor I could disconnect the open corner cable and have easy open access to unload and load the platform.

Using this design, when either my snowmobile or motorcycles would be stored on the raised platform, the area below the platform would be completely open. So in the months I have the snowmobile stored I’d still have full access to the floor space under the platform. Based on a platform load of 1200 pounds, each corner of the platform would be 400 pounds. The load on three corners of the platform would be on the vertical posts, and the load on the truss connected to the platform would only be about 400 pounds. I can easily now apply 3/4" plywood to each side of the truss to strengthen it and spread the 400 pound further across the truss.

I like to use commonly available parts, so the guide rollers could be plastic wheeled garage door rollers. The cable could be common ¼” garage door opening cables. Pulleys would be common hardware products. The 120v winch and cable drums are commonly available through Northern Tool and other suppliers. Anyone have a similar system or ideas to plan for on this system? I am open to all suggestions.

 

[melon16]

sounds great in theory, but if you built some shelving and picked up a small forklift or even used a chainfall and an overhead beam you may be better off.

for my uses, I picked up a mobile single post car hoist and pallet racking. works great and I also have the lift now too. all together Im under 5k (most of that is the lift)

 

[Mattlt]

These are made by a neighbor of mine. While it doesn't sound like exactly what you are looking for, maybe give them a look.

https://minneapolis.craigslist.org/csw/snw/d/lester-prairie-trick-lift-snowmobile/7064514049.html

 

[andyvh1959]

That Minneapolis craigslist post is no longer available.

I appreciate the input about the small forklift or a chainfall lift, but If I bought small forklift then I have to give floor space to that, which defeats the whole idea of keeping as much clear floor space as possible. I already have a chain block & tackle. But again as I described earlier I have a clearance issue, and I cannot put the full lift load on the trusses. Not without some extra posts down to the garage floor, and then those posts are in the way, which again becomes an access issue. I want the space under the lifted platform clear and accessible.

My cost is low, so far my total cost for the lift system, using wood for the platform that I already have is only $510 which includes $310 for the hoist I just bought at Northern Tool. By the time I have a working lift system I should be under $750.

The Strongway hoist is built in China, but is sold through Northern Tool so I have a local supplier I can go to for any issues. Right now I need to design the extension shaft and extra cable drum so both cable runs operate at the same time, for a cable run at each end of the platform. See the attached sketch, which shows the design from one end of the platform. Perhaps it looks complicated but it really is not. The hoist is mounted to the top of one post and the wall. the cable runs down, up and over pulleys to the platform. When it is in the lifted position the floor is totally clear under the platform. Its all parts I easily found on the net, so service and replacement parts are no issue.

Another design change I'm adding is casters under the platform, and a quick pin system for the cables to the platform. I'll be able to unpin the loaded platform and roll it to my workbench or out to the OH door to load the snowmobile onto the trailer or pickup.

 

[rslaback]

I can pretty much guarantee you that this will not lift level. The friction in the directional pulleys ensures that. If you could find magical no-friction pulleys it would work.

 

[andyvh1959]

I can't agree with that totally, at least not in respect to the pulleys themselves. Do you have actual experience to confirm that?

Each cable run winds on a drum on a shared shaft, so both turn at the same time/speed. But I can see if the cable on one drum winds up level and the other drum winds up in the center then the cable motion of one versus the other could cause uneven lifting. Hadn't considered that before. If I run two cable drums, neither drum has a level wind feature on the cable wrap onto the drums. I may have to consider a way to use the hoist with one cable drum and a cable equalizer.

Assuming the cable runs and pulley locations are parallel and equally spaced, side friction should not be an issue to cause tracking problems. The pulleys are simple bushing type, so, assuming the rotational friction in each pulley is equal the cables should lift at the same speed. I plan adjustable turnbuckles at the cable attachment to the platform so I can adjust the cable tension if needed.

Do you assume the platform is lifted fully unguided? Because it isn't. I have three channel posts attached to the garage walls in the corner where I locate the lift. Each post will be plumb in two planes and parallel to each other. Each channel post contains a trapped guide trolley that attaches to the platform, so during the lift the platform can only track up following the posts.

 

[andyvh1959]

Actually, after some more thought, I have ideas for a single cable drum hoist system that still works with my three post idea. It'll be a simpler single cable/pulleys system, with a bit more design in the platform. Thanks for challenging my earlier design as it got me thinking it through a bit more.

The bracing frame for the platform will be similar to a set of forklift arms. The hoist will lift it at the back center of the platform frame. Since I am not lifting anything into a 2nd floor or attic space (the garage has no attic space to store anything) the platform will stop about 36" below the ceiling, so that allows for a lift frame similar to this setup:

https://www.google.com/search?rlz=1...DCAs&uact=5#kpvalbx=_fXN2XqTkLI7YtAXsyKDAAg34

 

[Hooked]

I'm late seeing this but have you considered something like a boat lift hardware?

 

[SundayFunday]

I can't agree with that totally, at least not in respect to the pulleys themselves. Do you have actual experience to confirm that?

The problem comes from having a single cable on both sides of each end of the platform.
There is nothing to keep one side from raising faster than the other side except having the platform perfectly balanced and the friction of the pulleys being perfect.
If you imagine that the pulley hanging from the joist has more friction,or if it even stops, the opposite side will keep on lifting. It could even tilt while stationary.

One way to fix this would be to move the hoist down to the floor.(light blue circle) and have one cable up as high as the ceiling(green). This green cable is attached to the purple cable & the orange cable. As you wind in the green cable, it pulls both the purple & orange cables. This ensures that both sides come up at the same rate.

Hope my crude edits to your drawing are clear.

There are probably other ways to achieve the same thing, but this was something I quickly thought of.

Looks like a fun project though...good luck!

 

[melon16]

You mentioned forklift---maybe try and find a 3 point hitch forklift mast for cheap and attach it to the floor/wall? lots of capacity and you'd only need to worry about a power pack for it (most of the work done)

 

[andyvh1959]

Good points from both, thanks. Actually I never thought of a 3-point hitch forklift attachment, good idea! In fact I already have a electric/hydraulic power unit that would have worked for that had I thought of it. But I already have the hoist and pulleys. Plus some CL and Ebay local shopping found no 3-point fork lift attachments.

I have decided on a variation of my initial design. Instead of two hoist drums and two runs of cable, the hoist cable will be one run in the center. The hoist is still at the top, with one cable run down to a pulley, then up to two pulleys (same route as before) and down to the platform. The attachment at the other side of the platform will be an equalizer cable pulled up by the last vertical run of the single cable. The platform will be mounted to a L-shaped fork frame guided up the posts by trolleys (like a pair of fork lift arms). The top and bottom of the vertical legs of the forks will be guided by the trolleys in the posts.

This will give the same vertical speed for the vertical runs of the single cable. The equalizer attachment simply minimizes any twisting action of the forks/platform. The lift cable can be easily detached from the lift cable allowing easy access to load/unload the platform.

 

[andyvh1959]

Here is something I didn't think was so easy to find and reasonable cost: fork lift tines.

https://www.menards.com/main/b-380103.htm

 

[akdiesel]

For my four post lift I used two cables with eyelets that attached to the hoist. I used the cable crimps to lock the eyelets at the lengths I needed to keep the travel level.
Good luck. It was a fun projects to build.

 

[rslaback]

I can't agree with that totally, at least not in respect to the pulleys themselves. Do you have actual experience to confirm that?

Sorry for the reply delay.

Yes, I do.

Sent from my SM-G950U using Tapatalk

 

[andyvh1959]

Making progress. I have the 1100lb capacity hoist from Northern Tool. Last night I picked up the lift frame a friend welded up for me. These pics show the lift frame and location for the lift in my garage project. The vertical lines depict where the track posts will be. The horizontal line depicts the platform in the lifted position. It'll be big enough for my snowmobile and snowblower for summer storage. Or three lighter motorcycles for winter storage. I'll have over 5' clear height under the platform in the raised/storage position. The hoist will mount on four foot long steel angle I'll bolt through the doubled top plate of the wall, along with a section of Unistrut, bracing the hoist mount to each vertical Unistrut post. The red rectangle shows where the hoist mounts on the wall.

One picture shows the frame weldment, weighs 148 pounds. So I can just pick it up and move it around. The picture of the sheaves shows the main sheave I'll mount in the frame. The other sheave is for the equalizer cable on the end of the cable run, so both the front and back of the lift frame (as viewed going into the corner of the garage) will be supported/lifted by the hoist cable. Minus the lift frame and wood platform, I'll have just around 900 pound lift capacity on the platform. Snowmobile weighs 550 lbs, snowblower weighs 250 lbs, 800 lbs total.

I'm also going to box in the truss just above the hoist with 3/4" plywood to give it more vertical strength. Probably also use some tension bracing (steel) from that truss to each nearest truss. Then one length of Unistrut mounted horizontally from the trusses so I can put a pulley on it and use the hoist to lift items out of my pickup truck if needed.