Possible super-complicated frame, "portable" though

Technical Details
1

Hi everybody,
although I don’t really need it myself :joy: I kept thinking about a frame that is sturdy and portable, so it would be possible to take the maslow4 on location, and ideally not having to calibrate each time before use.
Now I have seen a low tech solution for a vertical frame using two ladders/kitchenstairs and a flat wooden frame, and I realise that that probably would be good enough.
But: this idea kept popping up in my mind, so I resolved to get it out of my head and into my computer, so I can get to other things. I’m posting it here for if someone else may want to build it, or use the idea.

My design parameters were:

  • portable, so no parts longer than 2 meter
  • capacity to cut full 1220x2440 boards, so the anchors would have to be 2600x3800 spaced
  • sturdy, so a metal spaceframe (triangles!), also to prevent warping
  • simple and repeatable construction method using the skills I have

so here it is:

spaceframe3 v1
spaceframe3 v11382×705 146 KB

The construction is made of steel tubes of 33.7x2.25mm, every tube has a lasercut 5mm steel plate welded on each end, which is in some cases bended to get the right angle.
The main concern was how to get a play-free joint. The solution I chose is a cone shaped middle piece, and stacked around that the 5mm steel plates, with different sized holes in them, so each plate centers itself on the cone. Not shown are a cap and bolt to screw everything rigid:

detail
detail1382×705 107 KB

The lasercut steel plates slide into the ends of the tubes untill they reach the stop and are then welded, so the welding is very limited and not very critical, the lasercutter does all the precise stuff. Some plates need to be bended, this does require some precision. And then there are 10 different sizes of tubes that have to be cut to length.

laser cut joint piece
laser cut joint piece1382×705 26.2 KB

Here is the big but:
this thing is quite heavy. with the 33.7x2.25 tube (this is called “1 inch” in holland) it weighs 85kg. So you would have to put it in 4 bags to be able to transport it. That is not very portable.
A superlight version of this frame uses 30x1.5mm tube, and still weighs 55kg.
But maybe that is not a problem for such a big frame, you tell me.
And how sturdy is it how much frame flex will it have?

Here is the link to the project, it opens in your browser and you can download it there if you want.

Please let me know what you think,

Arjen

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