I really need one of these ?

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Hi all

This is neat ?


Unsure how to raise it and lock it when my trike is on it ? any ideas ?

Now all I want is that , wood is great cheap light and easy to work , the thing folds flat for storage and the whole is light because it does not have electrics , gas engines , hydraulics or nuclear power !!!
 
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It's a lightweight wooden version of the one used for motorbikes. They use a hydraulic ram due to the weight of both the lift itself and the bike but something like that ought to lift via ordinary arm power. It'd lock with a diagonal brace on the long side with one end of the brace permanently fixed but pivoting and the other end able to slip over a fastened protruding bolt and then locked via a butterfly nut. I see the example is "locked" via the expedient of wedging a diagonal brace in the middle. Simple enough but all you'd need to do is nudge it for it to collapse. It's also not locking it at the full 90 degrees putting extra stress on the whole frame. Ensuring it locks at the full height would be better I think and bracing it at one side rather than the centre allows better access to the underside of the trike.

If you have an exceptionally heavy trike or otherwise can't raise 40kg or so by main strength then a screw drive from an old scissor jack could be butchered into service to both lift and lock it. Such a device would only act against it's mounts though and that lightweight wooden frame may require bracing around such points. If you google "motorcycle lift" you may get some ideas on design change or lift mechanisms.
 
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I see the example is "locked" via the expedient of wedging a diagonal brace in the middle.
At B , there seems to be to much wood at the point I have highlighted ?

It'd lock with a diagonal brace on the long side with one end of the brace permanently fixed but pivoting and the other end able to slip over a fastened protruding bolt and then locked via a butterfly nut.
Question is how to do that whilst getting it from flat to vertical , with only 2 hands.

It's also not locking it at the full 90 degrees putting extra stress on the whole frame.
Yes I had noticed that , also his wood sizes seem marginal there looks to be quite a bow in the top horizontal members ? although the Velo weighs at least 25kg unloaded with stuff and extras

If you have an exceptionally heavy trike or otherwise can't raise 40kg or so by main strength then a screw drive from an old scissor jack could be butchered into service to both lift and lock it.
IIRC they only lift about 12 " ?

I think one of his problems is because at C the moving part cannot go over the frame base hence he has blocks at A and D , although I am wondering if they stop it lying flat in the same plane and so being very hard to get the pivot action started whilst stood at one end ?

So if I am stood at the rear and have a foot plate on the frame to allow me to use my weight to stop the frame moving with a cord fastened to the top of the front frame could I get it lifting ? [ trike weighs about 30kg ]
If the brace passed a catch that allowed it passed but stopped it in the other direction it could self lock going up ?
Maybe one brace/catch each side and a separate cord to both to release them for the fold ?
maybe the cords could pass through some marine cleats to self lock as a bit of belt and braces [ no pun intended ] !

 
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I would have said that the entire thing is built a bit too "lightly" for the task in hand. But if it works for the guy that uses it, then fine.
I wouldn't risk an expensive glass shell on such a structure though.
It is basically only an upper and lower deck with end-frames that allow it to fall-flat/raise up through a parallelogram.
For it to raise, the bottom end needs NOT to skate along the floor (of course).
The effort to get the thing going is considerable though. It only gets "easy" once it is past about 35 degrees.
So the bottom end indeed needs a step-on part where the operator stands to anchor it to the floor, then he bends and lifts the upper-deck's front edge up and away from himself.
A system of "steps/detents" much like a traditional British deck-chair uses would be a good addition to allow "step-by-step" raising perhaps, with a stop to prevent it folding and collapsing in entirely the other direction (fun to watch, but a disaster for the trike.

I await your implementation of it Paul. Looks like a good idea.
 
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So the bottom end indeed needs a step-on part where the operator stands to anchor it to the floor, then he bends and lifts the upper-deck's front edge up and away from himself.
That's interesting I had imagined being at the other end to raise it ? however your idea sounds better , so no cord required to lift.

A system of "steps/detents" much like a traditional British deck-chair uses would be a good addition to allow "step-by-step" raising perhaps
I would have thought stopping at anywhere except vertical would cause it to nose towards the raiser ?

with a stop to prevent it folding and collapsing in entirely the other direction (fun to watch, but a disaster for the trike.
Well I envisaged the trike toe strapped to the frame for it and my safety ?

I await your implementation of it Paul.
So do I ;)

Looks like a good idea.
You mean it's better than an old work mate and a to small patio table ? strewth :rolleyes:
 
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Question is how to do that whilst getting it from flat to vertical , with only 2 hands.

IIRC they only lift about 12 " ?

If the diagonal is fixed at the bottom at the far end from where you lift the opposite end to attach it to will be right next to you at the top. I'd expect to be able to hold it at the top with one hand and attach the brace with the other though I accept not everyone could do that or would want to. Once somewhere near vertical the frame is holding it up and you'd be only be having to steady it.

Yes a scissor jack used as a scissor jack will not lift it enough. I was intending such a system to be sufficiently butchered and attached to the frame in such a way as to multiply the leverage to extend the range in the same fashion as a scissor lift multiplies a short stroke ram to extend by several times the ram's movement. Doing so will inevitably apply pressure to certain points in the frame though and will require substantial bracing or even going to a metal frame to accept such a loading. It'd be quite easy to end up with a frame that outweighs the load it's expected to hold.

The block at D is what the brace is holding against and that extra wood on the brace is just the bit the butts against D block having made a L shape with the main part of the brace. Because he has that block at D he put one at A to prevent any stress on laying it as flat as it goes. D block prevents it going truly flat and A block then reciprocates the effect at the other end. Neither A nor D block are needed if it were to be braced at one of the long ends rather than the middle and it would thus fold completely flat.

One alternative would be to utilise a ratchet strap at the points I have indicated for the brace. Use the power of the ratchet to raise it and design it so it can't go past the vertical. You'd have to utilise similar blocks as above so as not to start off with it completely flat, allowing the strap to pivot the frame at the two points it's not attached to as it shortens. No brace needed as the strap and prevention of going past vertical perform that function. Lowering would need to be done manually as ratchet straps don't work in reverse.
 
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If you use a footplate and cord method as you suggest you could design the frame to go ever so slightly over centre but no further. This would allow it to hold it's upright position whilst you then pegged it to prevent movement. If you made one of the four lower pivot blocks taller you could stick a bolt through that and the upright to act as the peg preventing it dropping. You'd want to get the peg a distance from the pivot to remove some of the potential leverage should the load get nudged hence needing to make that block taller. Lowering would be easy enough with the peg removed only needing to pull it back over centre before lowering.
 
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There is another way.
It might be easy & also a bit of fun.
How high off the deck are we looking to raise the trike/bike/quad as in the bottom edge of the wheels?
 
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Popshot - like the over centre idea and cord is simplest and lightest ?

DannyC - well in my case about waist height [ of course waist height varies as some of us have very short fat hairy legs ? ]
 
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Popshot - like the over centre idea and cord is simplest and lightest ?

DannyC - well in my case about waist height [ of course waist height varies as some of us have very short fat hairy legs ? ]
I will have you know that since I used Veet for men my legs have never been smoother or less hairy.
 
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This conversation has given me an idea for modification to my trike stand. It is fixed and requires the trike to be lifted and placed on it. This is a task that is becoming more difficult due to obesity - the trike's not mine, due to stuff being added to it. Taking it all off just to raise it off the floor is not worth it but it is nice to be able to get under it.

Why could you not make the parallelogram from steel and have a place where you could insert a bar, or similar, to pull down on to raise it? Hmm, a problem, you would still have to lift the bar to insert it. Seriously, I think it would work. The top surface could be a skeleton arrangement with cross slats fitted for the wheels to drop into slightly to prevent rolling. This would also satisfy different track widths, trike lengths, etc., and also prevent chipping that nice new paint.

Oh, darn, there's another new project and I still haven't finished the last six.
 
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