Daktent

[Dolf]

Goed gedoen Peter!! Hoe sê hulle, "Alles kan opraak solank jou planne net nie opraak nie!"

[davejones]

Nice work Peter

[Peter Connan]

Here's what Tentco's RTTs weigh:

1.2 x 1.25 m (Closed) & 1.2 x 2.45m (Open) - 52 kg
1.4 x 1.25 m (Closed) & 1.4 x 2.45m (Open) - 54 kg
1.6 x 1.25 m (Closed) & 1.6 x 2.45m (Open) - 56 kg
Height at apex: 280mm (Closed) & 1.30m (Open)

Your 70kg target is very competitive...

Most RTT's are built on a base made from 8mm marine plywood. The problem for me was that in my opinion this would not be strong enough for a tent this large. I think Tentco's 1.6m model is about the limit for this type of construction, and I suspect it leans rather heavily on it's ladder.

To solve the strength problem without adding a lot of extra weight, I investigated a number of manufacturing methods, up to and including Carbon Fibre and Aluminium honeycomb sandwich panels. While some of these technologies would have resulted in a slightly lighter construction, they would have been extremely expensive.

What I finally settled on was this:

RTL1_1.jpg (223.62 KiB) Viewed 3492 times

I made an Aluminium frame consisting of laser-cut end sections incorporating the hinge and 20mm square tubes welded across. Using Sikaflex glue and large-head rivets I then attached a sheet of 4mm plywood to the bottom side. Next I cut 20mm thick polystyrene panels to fill all the gaps, and glued them in using Alcolin cold glue, and fitted a second sheet of 4mm plywood to the top, again using cold glue (polystyrene-wood), Sikaflex and rivets (aluminium-wood).

These panels weigh approximately 18kg each, and the one is 7mm shorter than the other so that the hinges fit correctly.

[Peter Connan]

The secret to creating more usable inside space is the linkage holding the tent open.

Most RTT's use three arms all hinged at the same point where the two floor panels are hinged. The problem with this is that those arms cannot be wider than the actual panels, and because of this the roof tapers down sharply from the peak. Normally this is fine because you would be sleeping across the tent, so your feet will be in the low section and at 2.45m the tent is long enough that you do not need to get right into the ends.

But in this case I did not want to make my tent longer as I still wanted room on my roof rack for a few jerry cans and a gas bottle, so I had to find a way to make the sides of the tent more vertical, and because the divider dividing the tent into two rooms is above the spine, we will be sleeping in the length of the tent.

My solution was to have the central arm hinged at the panel's hinge point as normal, but to have the two end arms suspended on a scisor linkage so that as the tent is opened up they effectively become longer:\

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RTL+tent.jpg (230.69 KiB) Viewed 3491 times

The added advantage of this is that when the tent is fully open, these linkages are effectively straight, and thus they carry the weight on the unsupported panel, thus the tent is strong enough to operate without support from the ladder.

[Rudolph]

Hi Peter,

This is a properly planned DIY project!! Congratulations this is awesome work!! I can see the engineering brain working here.

Regards,
Rudolph

[Gerrie]

Peter, nou wanner kom die regte canvas?

Dit lyk darem maar bakgat, hoor!

[Peter Connan]

Gerrie I need to test it first to make sure I have the design of the canvas right, and sort out all the details (such as lights and pockets and so forth) and then I need to find somebody who can do the canvas work at a reasonable price.

So I need to go and camp for a weekend where it is not too cold but before it starts raining.

The deadline is March 2012, but I would prefer to have it ready by mid December.

[ChristoSlang]

Most RTT's are built on a base made from 8mm marine plywood. The problem for me was that in my opinion this would not be strong enough for a tent this large. I think Tentco's 1.6m model is about the limit for this type of construction, and I suspect it leans rather heavily on it's ladder.

Yep, that ladder works very hard on mine (a 1.4m jobbie). And the marine ply on the open part squeaks & groans, even though I'm not big or tall by any stretch of the imagination...

[Nikolai B]

Ziet er goed uit!! Maar ja ik heb een korte (Patrol bedoel ik he WWW WWW )

[Peter Connan]

Nikolai gelukkig is daar net een van jou, so jy het nie so 'n lang tent nodig nie. Dalk net 'n swag?