UNICAT lift up roof ?
- Thread starter sherwood
- Start date
essentially an Alaskan camper style life - there are a few build threads in this section with similar setups, each person uses a different alignment rail setup
http://www.expeditionportal.com/forum/forumdisplay.php?f=74
http://www.expeditionportal.com/forum/forumdisplay.php?f=74
Victorian
Approved Vendor : Total Composites
As mentioned in my response to your PM, they are electrical. Please understand, that I can't tell you more about it as I'm not sure if I would be giving away company secrets.
Anyhow, just a word of advice: It's not as easy to construct as it may looks like!
Good luck!
Anyhow, just a word of advice: It's not as easy to construct as it may looks like!
Good luck!
sarconcepts
Adventurer
well, I certainly don't know what Unicat uses, but I do know what I did to get a 300 lb roof to lift, with all four cylinders moving at exactly the same speed, up & down, as well as a linear track system that works, well out of level. I can't say i looked for the cheapest system, but to be honest, it didn't cost that much.. ...($ 1300.00 +- total)
I briefly mention it here
www.expeditionportal.com/forum/showthread.php?t=34294&page=6
in post #58
then go into great detail on the builds website listed in the post
I briefly mention it here
www.expeditionportal.com/forum/showthread.php?t=34294&page=6
in post #58
then go into great detail on the builds website listed in the post
michaelvanpelt
Observer
The Pangaea
Hello
I assume you mean like this. Although its not white anymore you get the idea.
Mike
www.globalxvehicles.com:
Hello
I assume you mean like this. Although its not white anymore you get the idea.
Mike
www.globalxvehicles.com:
Attachments
dwh
Tail-End Charlie
Usually it's done with hydraulic rams (Alaskan) or electrical or pneumatic versions of the same thing.
As sarconcepts explains, keeping them synced is the problem when raising/lowering. The main drawback that I can see from that, is that you have to leave a bit more room between the top and bottom to allow for the roof going up not quite square.
Another problem with the hydraulic and pneumatic rams is that you can get "creep" so they often have some sort of block or pin that you put in to keep them from creeping down.
And of course, hydraulic brings the spectre of an oil leak.
I've often thought that a more or less standard machine type worm drive screw jack arrangement might work well. As an example, here are a couple of different arrangements. These are very much unsuitable for what we're talking about, but you'll get the idea immediately:
http://www.nookindustries.com/jack/JackArrangement.cfm
The first obvious problem with that sort of setup, is that the nut remains stationary, while the screw goes up and down. I think that's probably the reverse of what would be needed for a camper roof lift. To see what I mean, here is a link. In the main photo, notice the screw in the center. On that rig, the screw is stationary, while the nut rides up and down:
http://www.concisemotion.com/screwjacks.htm?gclid=CPG2xd6Gz6UCFYHc4Aod3nXAkw
Here's almost exactly what I'm talking about - at the bottom of this page, there are a couple of pics. For a camper roof lift, I really like the look of the last one with the motor in the center of the main shaft (though the rig in the pic is way too burly for a camper roof lift):
http://www.lim-tec.com/english/products4.html
This sort of arrangement could easily be cobbled together by a homebrewer with a couple of shafts, four screw/nut sets, some worm gear sets, two right angle gearboxes and a few bearings (could very likely just get everything from Grainger's). You'd need say one set of worm/ring gears for each corner, and perhaps a 5th set for the motor to drive the main shaft (or 6 - make them all the same and you could carry a single set in the spares box):
http://www.concisemotion.com/wormgear.htm
http://www.tolomatic.com/products/product_detail.cfm?tree_id=141&category=gearboxes-gear-boxes
Then of course, you also need a motor...how about a Bosch VW starter motor? If that thing ever quit working anywhere in the world I would bet you could find a replacement or some shade tree mechanic who could rebuild it on the spot. Or perhaps some small standard type winch motor. If you did it right, you could even add a hand crank to the main drive worm "just in case". It probably wouldn't be all that hard to turn, but you'd have to turn it a whole lot of times. Make the nut the same size as the lugs and you could use your lug wrench to crank the roof up or down in a pinch.
The whole rig could be easily built right into the base frame of the box, and end up only with 4 screws sticking up through the floor. Add a few access covers underneath and put it on the "annual inspection and maintenance" list. Attach the roof to the nuts, put on some top/bottom limit stops and away you go.
A couple of advantages I see right off are that it will certainly be synchronized. And that setup -will- go up and down square no matter what wonky angle the truck is parked at, so you can build the top with a tighter fit to the bottom.
It's relatively simple, yet quite mechanically robust. Bulletproof basically...about the only thing that can fail is the motor. Weight will be irrelevant - even small screw jacks can lift tons. Unequal loading of the roof will be irrelevant as well.
Another advantage that I particularly like, is that wherever the roof is when you release the switch or stop turning the crank - there it stays. It's mechanically -locked- in place. So if you wanted to, you could easily drive around with the roof raised.
Gale force winds? Six feet of snow on the roof? Bah! Piffle! It also can't leak or creep.
Of course, you could just buy all the parts off the shelf. Here's an excellent document that shows how to do the engineering math to figure loads and torques and whatnot, and it also shows some really sweet products:
http://mdmetric.com/prod/pti/Muli.pdf
For the guides - again, standard industrial linear guides should get the job done:
http://www.thomsonlinear.com/website/com/eng/products/linear_bearings_and_guides.php
This one looks sorta sexy. A set of eight - two on each wall - should keep the top perfectly aligned:
http://www.thomsonlinear.com/websit...uides/profilerail/microguide_linear_guide.php
As sarconcepts explains, keeping them synced is the problem when raising/lowering. The main drawback that I can see from that, is that you have to leave a bit more room between the top and bottom to allow for the roof going up not quite square.
Another problem with the hydraulic and pneumatic rams is that you can get "creep" so they often have some sort of block or pin that you put in to keep them from creeping down.
And of course, hydraulic brings the spectre of an oil leak.
I've often thought that a more or less standard machine type worm drive screw jack arrangement might work well. As an example, here are a couple of different arrangements. These are very much unsuitable for what we're talking about, but you'll get the idea immediately:
http://www.nookindustries.com/jack/JackArrangement.cfm
The first obvious problem with that sort of setup, is that the nut remains stationary, while the screw goes up and down. I think that's probably the reverse of what would be needed for a camper roof lift. To see what I mean, here is a link. In the main photo, notice the screw in the center. On that rig, the screw is stationary, while the nut rides up and down:
http://www.concisemotion.com/screwjacks.htm?gclid=CPG2xd6Gz6UCFYHc4Aod3nXAkw
Here's almost exactly what I'm talking about - at the bottom of this page, there are a couple of pics. For a camper roof lift, I really like the look of the last one with the motor in the center of the main shaft (though the rig in the pic is way too burly for a camper roof lift):
http://www.lim-tec.com/english/products4.html
This sort of arrangement could easily be cobbled together by a homebrewer with a couple of shafts, four screw/nut sets, some worm gear sets, two right angle gearboxes and a few bearings (could very likely just get everything from Grainger's). You'd need say one set of worm/ring gears for each corner, and perhaps a 5th set for the motor to drive the main shaft (or 6 - make them all the same and you could carry a single set in the spares box):
http://www.concisemotion.com/wormgear.htm
http://www.tolomatic.com/products/product_detail.cfm?tree_id=141&category=gearboxes-gear-boxes
Then of course, you also need a motor...how about a Bosch VW starter motor? If that thing ever quit working anywhere in the world I would bet you could find a replacement or some shade tree mechanic who could rebuild it on the spot. Or perhaps some small standard type winch motor. If you did it right, you could even add a hand crank to the main drive worm "just in case". It probably wouldn't be all that hard to turn, but you'd have to turn it a whole lot of times. Make the nut the same size as the lugs and you could use your lug wrench to crank the roof up or down in a pinch.
The whole rig could be easily built right into the base frame of the box, and end up only with 4 screws sticking up through the floor. Add a few access covers underneath and put it on the "annual inspection and maintenance" list. Attach the roof to the nuts, put on some top/bottom limit stops and away you go.
A couple of advantages I see right off are that it will certainly be synchronized. And that setup -will- go up and down square no matter what wonky angle the truck is parked at, so you can build the top with a tighter fit to the bottom.
It's relatively simple, yet quite mechanically robust. Bulletproof basically...about the only thing that can fail is the motor. Weight will be irrelevant - even small screw jacks can lift tons. Unequal loading of the roof will be irrelevant as well.
Another advantage that I particularly like, is that wherever the roof is when you release the switch or stop turning the crank - there it stays. It's mechanically -locked- in place. So if you wanted to, you could easily drive around with the roof raised.
Gale force winds? Six feet of snow on the roof? Bah! Piffle! It also can't leak or creep.
Of course, you could just buy all the parts off the shelf. Here's an excellent document that shows how to do the engineering math to figure loads and torques and whatnot, and it also shows some really sweet products:
http://mdmetric.com/prod/pti/Muli.pdf
For the guides - again, standard industrial linear guides should get the job done:
http://www.thomsonlinear.com/website/com/eng/products/linear_bearings_and_guides.php
This one looks sorta sexy. A set of eight - two on each wall - should keep the top perfectly aligned:
http://www.thomsonlinear.com/websit...uides/profilerail/microguide_linear_guide.php
Last edited:
lost1
Member
I have just completed the same thing on my mog as what you are trying to do. First I started with a system of pneumatic cylinders. I never got the 300+lb roof (7'x15) to raise evenly despite all kinds of valves etc. Then I tried with a screw type system on all 4 corners with a bicycle chain linking them together and a 12 volt motor. This failed because bike chains don't work well when laying on their side and a non-acme type screw binds when you have 2 opposing nuts on it.
I then looked at linear actuator like what people use for opening their driveway gates but they seemed to finicky and fragile SO
I found 4 electric camper jacks the kind that are used for lifting pickup campers. These things are the business. They use an acme type screw which goes up and down pretty quick. They can lift 3000lbs over 36" high. They have an autostop clutch at max and min extension. each lifter has a small socket attachment where I can attach a manual crank in case of
motor failure. They work on 12 volts and you have the option to buy all the switchgear to equalize the lifting or you can take 4 car electric window switches and manipulate them together.
My system cost
I then looked at linear actuator like what people use for opening their driveway gates but they seemed to finicky and fragile SO
I found 4 electric camper jacks the kind that are used for lifting pickup campers. These things are the business. They use an acme type screw which goes up and down pretty quick. They can lift 3000lbs over 36" high. They have an autostop clutch at max and min extension. each lifter has a small socket attachment where I can attach a manual crank in case of
motor failure. They work on 12 volts and you have the option to buy all the switchgear to equalize the lifting or you can take 4 car electric window switches and manipulate them together.
My system cost
Victorian
Approved Vendor : Total Composites
Ford Prefect
Expedition Leader
Wow, that sounds like a pretty good deal there.
I know that Mike Hiscox mentioned that Unicat spends about 50K on their lift roof over the cost of a typical roof.
Don't forget that when you lift you end up with a lot of other issues like insulation, and weather proofing. Not that this is all that hard, just that it is something to take into account.
I know that Mike Hiscox mentioned that Unicat spends about 50K on their lift roof over the cost of a typical roof.
Don't forget that when you lift you end up with a lot of other issues like insulation, and weather proofing. Not that this is all that hard, just that it is something to take into account.
BCarmichael
New member
Synchronized hydraulic lift system
First post here.
Looks like a lot of thought goes into how to get a roof up. I have no idea if this would work, but looks it might be helpful. Looks like a cool idea.
http://hydromechusa.com/
Inventor and engineer David Brown has developed a new, patent pending, fully-integrated hydraulic lift system that can be utilized in recreation vehicle, boat lift, residential construction and many other applications. This proprietary system consists of a synchronized hydraulic pump, reservoir, and telescoping linear actuators.
The hydraulic pump is available in two configurations designed hydraulic fluid up to 1,500 psi. The Power Duo is a motor-driven pump that operates two hydraulic cylinders. The Quatro pump controls 4 hydraulic cylinders or our unique telescoping actuators. The Quatro pump is available in manually-operated or motor-driven versions with either gravity or positive-displacement return. The pump’s flow capacity is engineered specifically to your application’s requirements.
The telescoping linear actuators are based on technology used to raise a forklift. The linear actuators are available in a range of bore sizes and lift capacities. They can be designed to fit your specific application.
First post here.
Looks like a lot of thought goes into how to get a roof up. I have no idea if this would work, but looks it might be helpful. Looks like a cool idea.
http://hydromechusa.com/
Inventor and engineer David Brown has developed a new, patent pending, fully-integrated hydraulic lift system that can be utilized in recreation vehicle, boat lift, residential construction and many other applications. This proprietary system consists of a synchronized hydraulic pump, reservoir, and telescoping linear actuators.
The hydraulic pump is available in two configurations designed hydraulic fluid up to 1,500 psi. The Power Duo is a motor-driven pump that operates two hydraulic cylinders. The Quatro pump controls 4 hydraulic cylinders or our unique telescoping actuators. The Quatro pump is available in manually-operated or motor-driven versions with either gravity or positive-displacement return. The pump’s flow capacity is engineered specifically to your application’s requirements.
The telescoping linear actuators are based on technology used to raise a forklift. The linear actuators are available in a range of bore sizes and lift capacities. They can be designed to fit your specific application.
dwh
Tail-End Charlie
Neat.
With 1000lb capacity it might not be suitable for some of the bigger rigs.
This part sort of got me...
"Our actuators are engineered — and have been tested — to significantly outlast the 300-cycle industry standard."
Okay, so I'm sure they'll operate more than 300 times. But who knew the industry standard was 300 cycles? Reasonable I suppose for a pop-top camper used a few times a year, but for a long term overland journey?
Also curious as to how they hold up to side loading such as heavy winds.
With 1000lb capacity it might not be suitable for some of the bigger rigs.
This part sort of got me...
"Our actuators are engineered — and have been tested — to significantly outlast the 300-cycle industry standard."
Okay, so I'm sure they'll operate more than 300 times. But who knew the industry standard was 300 cycles? Reasonable I suppose for a pop-top camper used a few times a year, but for a long term overland journey?
Also curious as to how they hold up to side loading such as heavy winds.
david506th
Adventurer
I am not sure of the industry standard but I know that one of the machines in my factory right now runs between 5000-7000 motions a day, 5 days a week all year. We have not done anything to replace it or maintenance it since we installed it almost exactly one year ago. We regularly rebuild hydraulic cylinders and I fully suggest everyone keeping a rebuild kit with them. They are not that hard to work on.