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Raise the Roof

PostPosted: Sun Oct 14, 2012 8:44 pm
by Tomcat98
Good evening,

I am looking for ideas on how to raise a trailer from a stored travel configuration to a camping configuration. I have attached a file to help illustrate what I am wanting to accomplish.
Bike Barn.pptx
(54.64 KiB) Downloaded 302 times


Any ideas?

Tomcat98

Re: Raise the Roof

PostPosted: Sun Oct 14, 2012 9:02 pm
by droid_ca
Have you looked at sages trailer in the hall of fame

Re: Raise the Roof

PostPosted: Sun Oct 14, 2012 9:17 pm
by Tomcat98
Do you know what it is listed under? My initial thought was to use some type of external hoist system.

Tomcat98

Re: Raise the Roof

PostPosted: Sun Oct 14, 2012 10:20 pm
by droid_ca
http://purplesagetradingpost.com/sumner ... epage.html
Here is a link to his personal webpage hope it helps

Re: Raise the Roof

PostPosted: Mon Oct 15, 2012 6:20 am
by bonnie
As it happens, I am working through the same issue. When I saw your powerpoint, I thought there's BUB. I am working on a four point lift system. It will be placed in the middle of the box and using a lift mechanism much like what's used for hiding flat panel TVs. I got the idea for the brace parts while cruizing YouTube and saw home made camera rails. I haven't fabbed everything up yet, but will soon.

If you search for poptop you will also find a wealth of ideas.

Good luck.

Re: Raise the Roof

PostPosted: Mon Oct 15, 2012 10:44 am
by aggie79
Bonnie,

I can't wait to see your solution.

I've been kicking this idea around for some time. The obivious difficulty is synchronizing the movement of the lift so that all four corners lift at the same time and at the same height.

Take care,
Tom

Re: Raise the Roof

PostPosted: Mon Oct 15, 2012 11:07 am
by bobhenry
Maybe I should rethink my bed lift in the caboose tiny house. I found this site a few years back and concidered constructing gally lid lifts that were air actuated. No worry about coordinating lifting power as the air pressure would be equal at all lift points.

http://www.llund.com/pne_cyl.htm

Re: Raise the Roof

PostPosted: Mon Oct 15, 2012 4:34 pm
by KCStudly
bobhenry wrote:No worry about coordinating lifting power as the air pressure would be equal at all lift points.


Actually, it seldom works out that way in real life. Yes the pressure is the same in a balanced system, but the resistance due to friction and disimalar weights at the different corners would be unlikely to be the same, so even air lifts could bind. Sorry. :NC

For an all corners lift the cable with pulleys and a winch method gets my vote. Simple, easy to understand, light weight, relatively inexpensive and easy to adjust at the equalizer bar. Does take some planning and realestate, but, you know there's always the "cake and eat it, too" thing to deal with. ;)

Next best, IMO, for either 4 or 2 corners lift would be screw jacks with some sort of decoupler to allow manual cranking in a fault mode.

Of course that is given the existing situation of a heavy roof and modest human power. First choice would be a lighter roof. ;)

$.02 and not worth that.

Re: Raise the Roof

PostPosted: Mon Oct 15, 2012 7:44 pm
by bdosborn
I would look at Alaskan Campers, they have a hydraulic lifting roof system.
Seal Repairs

Lifting System

Lots of expedition trucks have lifting roofs, you should cruise on over to the expedition portal.

Expedition Truck with Electric Actuators



Bruce

Re: Raise the Roof

PostPosted: Tue Oct 16, 2012 12:46 am
by Bogo
This is an issue that has been solved many times by the pop up tent trailer builders. Likely the easiest way to to grab the lifting system from an existing pop up trailer and use it. Cable/pulley lifts are the easiest to conceptualize, but the sliding parts for the vertical lift columns can be hard to make yourself. Just grab them from an existing pop up trailer maker, or scavenge an old junked trailer or two.

For hydraulic systems google "hydraulic pop-up camper lift" without the quotes. There are a few makers out there. All I've looked at require 12VDC to operate the hydraulic pump. Some just hydraulically actuate the existing cable lift system, others have cylinders for all 4 corners. All cost allot.

BTW, I'm also thinking of doing a small 6'x12' hard sided pop up trailer like you are thinking of. I've also thought of making a hard sided pop up back for a pickup, but the pickup I was going to put it on turns out to have frame problems. :cry: My plan is to use the coil spring in tube method for lifting the top. To move the coil spring I'll have a bicycle chain loop at each end. That will be driven by a hand crank that is geared down a bunch. Once the top is lifted up, I'll place a cover tube in each corner to support the roof against collapse. My quick guess is it will be about $500 to $600 in new parts to do a coil spring lift mechanism for 42" lift. The biggest cost is having to buy 10 * 50" long extension springs to get the 4 I need.

Re: Raise the Roof

PostPosted: Tue Oct 16, 2012 7:41 am
by aggie79
For my #2 build, I would like a slouchy/standy design. Whatever I come up with needs to fit into the garage, so that means a design that allows the trailer height to increase once at the campground.

Lifting a roof only is difficult enough, but lifting a roof with with sidewalls adds additional challenges to racking and uneven lifting. In my current sketches, I have a hybrid roof design with partial front and rear walls that lift with the roof. The partial sidewalls do not lift with the roof. They fold into the trailer and manually would be flipped up in place after the roof is up.

To eliminate side to side racking and to reduce the lifting points from two to one on each of the two end walls, the end wall would be constructed like a drawer with two vertical slides. A single linear actuator would be mounted to the middle of the end wall structure and would raise and lower the end wall.

With the above, a design that has a fixed or rigid connection between the roof and the two end walls would require that the two linear actuators at each end to be synchronized. So instead of worrying about the synchronization, I came around to hinging the top of each end wall to the roof. This way it wouldn't matter if the front wall is raising/lowering at a different speed than the rear wall or vice-versa.

Re: Raise the Roof

PostPosted: Tue Oct 16, 2012 9:03 am
by droid_ca
aggie79 wrote:For my #2 build, I would like a slouch/standy design. Whatever I come up with needs to fit into the garage, so that means a design that allows the trailer height to increase once at the campground.

Lifting a roof only is difficult enough, but lifting a roof with with sidewalls adds additional challenges to racking and uneven lifting. In my current sketches, I have a hybrid roof design with partial front and rear walls that lift with the roof. The partial sidewalls do not lift with the roof. They fold into the trailer and manually would be flipped up in place after the roof is up.

To eliminate side to side racking and to reduce the lifting points from two to one on each of the two end walls, the end wall would be constructed like a drawer with two vertical slides. A single linear actuator would be mounted to the middle of the end wall structure and would raise and lower the end wall.

With the above, a design that has a fixed or rigid connection between the roof and the two end walls would require that the two linear actuators at each end to be synchronized. So instead of worrying about the synchronization, I came around to hinging the top of each end wall to the roof. This way it wouldn't matter if the front wall is raising/lowering at a different speed than the rear wall or vice-versa.


I'd be interested in seeing a picture of this design sounds like a good Idea
I just had an idea similar for a design that consisted of an "L" shaped track that ran up and down and your other wall folds up into but the only problem would be you would see the Linear :thinking: actuator unless you were able to lift it some how from the top....Hmmm

Re: Raise the Roof

PostPosted: Tue Oct 16, 2012 2:44 pm
by KCStudly
aggie79 wrote:So instead of worrying about the synchronization, I came around to hinging the top of each end wall to the roof. This way it wouldn't matter if the front wall is raising/lowering at a different speed than the rear wall or vice-versa.


If I understand you correctly, Tom, you're talking about having the end walls telescope up vertically out of the lower (fixed) end walls on something like rigid drawer slides. Doing one end then the other, then having side wall panels that fold up (or swing down out of the roof).

Just make sure to check the arc swing of the roof vs. the individual wall lifts. Having a hinge on the top of the wall may not be enough to keep the roof arc from pulling in on the wall as it rises, resulting in possible binding and damage.

In other words, if you leave one end of the roof down (let’s say the back) during the raising procedure, as the end that is lifting goes up (let’s say the front), it also swings closer toward the back in the horizontal aspect. The roof length, which is fixed, becomes the hypotenuse (roof = C) and the top of the fixed side wall starts out as the adjacent side, or base of a triangle (horizontal length = B). At first they are the same, however, the higher you lift the front (lift = A) the shorter the distance from the lifting edge of the roof to the non-lifting edge wants to be. The adjacent side of the triangle (B) gets shorter (binding your drawer slides). Pythagorean formula: A^2 + B^2 = C^2. So a 10 ft long roof will swing back at the front about 7.6 inches when lifted 42 inches. A = (120^2 - 42^2)^1/2 ergo A = 112.4

Or maybe I completely misunderstood your proposal. :thinking:

Re: Raise the Roof

PostPosted: Tue Oct 16, 2012 3:49 pm
by aggie79
KC,

You "hit the nail on the head" about my design musings (and actually explained it better than I did.)

I did consider the triangulation "lengthening issue". If I build this the length of the roof would be 12-15. The roof as well as the rest of the camper would be lightweight "foamie-like" construction coupled with overspec'ed actuators (rated for 2-3x the actual weight of the roof). Both acutuators would be run at the same time. Even with a 6" vertical height difference there would only be a 0.1" increase in length. One of the end wall hinges would be able to move horizontally.
:worship:

The backup plan is to only hinge one of the roof to end wall connections. The other end would be free - I'd strap it to keep the roof from flying off - so the length change would not come into effect during lifting. When the roof is in the up position, I would use latches to anchor the roof to the end wall.
;)

Backup plan #2 is to use actuators with stepper motors and feedback tied into a laptop to ensure the vertical lifts are exact - not! :shock:

Take care,
Tom

Re: Raise the Roof

PostPosted: Tue Oct 16, 2012 4:40 pm
by angib
The parallel-lifting rectangular top is a simple idea that is very difficult and complex to carry out. I prefer a less ideal design that can be built easily, which is to hinge the top at one end. Lifting it then becomes a simple operation that may be able to be done without any mechanical assistance, except maybe some large gas springs.

I've searched and searched and can't find the 3D design that I did for a competition Mike set up, but here is a similar idea based on the Winter Warrior. It's just one big box, hinged partway up the front. This enables it to have a very aerodynamic shape when down but provide standing headroom over half the length when up.

Image