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By MikeG.
#1337654
nirajshah31 wrote:Oooh- sorry missed that.
Thanks!
That design has been tested and passes CE/EU standards. So I assume it must work


It's manufactured in a factory. They have materials and tolerances you can only dream of. In a home workshop you will not achieve anything safe using the path you seem determined to follow. You aren't the first poster who has started a "how do I do this?" thread and only taken any notice of responses that support their predetermined plan. Well, sorry, but the course you are embarked on is the wrong one, and if you won't hear it, that's not our fault.

Good luck with this. I'm outta here.
By Roland
#1338161
I’ve just posted this in another thread, but here goes again.

Image

After his trial assembly I cut a smiley curve across the triangle plate. Loosen the bottom bolt half a turn and you can fold the frame for storage. The wooden knob only has to be finger tight to hold the frame open. The bolts are M5 furniture bolts with a T-nut on the other side of the knob, and a “threaded connector” on the other side of the spar. The top bolt is filed exactly to length so that it anchors but doesn’t bind.
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By TheTiddles
#1339696
As Mike had pointed out, you seem to be looking for confirmation more than critical review.

Putting the stop a few mm away from the pivot creates the most force on the smallest area, so is asking for a failure. Just because someone has done it, doesn’t mean it’s right, and a CE Mark doesn’t mean it’s tested for all eventualities.

A cord at the bottom of the triangle is the easiest option but I would never recommend it, as with a bit of slack you’ve created a ligature, not a good thing to have around little ones.

Mike’s bi-folding link could be quite elegant if you planned it well, or use the quadrant approach as also described.

Never pivot on a screw, but using a ground steel shoulder screw against wood is going to result in one of those materials coming off worse. Increase diameter to increase area and reduce pressure.

Aidan
By nirajshah31
#1339699
Hi Aiden
Thank you for helping - i do appreciate it.
So i want two dowels at the top rather than a centre one, therefore using the rounded top is aethetically pleasing. but then as you say i run into trouble.

So, i'll add a removeable bar to make it a full triangle, using hand knob screw or furniture screw - so 4 (one on each end). Will be a pain to remove but makes it safe.

Centre pivot - please explain what i should do. increase diameter of the hole vs screw... so M10 screw but hole of say 20mm? reduce pressure by using a plastic washer? pls explain in as much detail/ picture of the item as possible

thanks again - i am taking your advice on board
User avatar
By TheTiddles
#1339889
Regarding the pivot point, it’s probably not worth fretting over (engineering joke, get it??!). A barrel bolt would give you a smooth head either side (or you could counterbore it) and a smooth surface to rotate against, they’re very cheap but you might have to buy 20.

If you use a third bar to complete the triangle, you could use a spacer between the two sides so the bottom bar sits between the angled sides (that is probably confusing, but draw out the layup and you’ll see, hopefully)

Aidan