It could be as the wider part of the drill seems to have a flat edge on it.

You can see where the confusion has been caused though

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DIY | Donnas dream house

This are similar to the easy step bit, but both section are normal length.

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Hardwood is not a bad idea. I'm not sure I would trust it to be rugged enough in the field. I can see advantages in ease/cost of production, but the lack of commercial examples of hardwood based rigging systems seems to suggest it is maybe not the optimum material.

I might give it a shot though. What wood do you recommend?

The 1mm tolerance was more about the hole distance than the diameter, but I think even if I were to drill a 16mm hole leaving a 1mm gap, I could easily pack it on the inside to ensure a reasonably tight fit before any tightening is applied. I don't envisage the aluminium moving much under tightening

ok have i got this right
you are relying on the metal closing and gripping the rod ??
other ideas a u shaped hole 2mm less than the bar height and an oversized washer or bar to tighten across the top

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we are all ------------------still learning

Yes. The rods need to come out to change configuration of the camera rig or to add accessories to the rails. Need to be able to quickly release them.



I'm having trouble visualising what you're describing. What do you mean by the bar height? Are you suggesting that I don't tap the holes, but instead have a nut and bolt to tighten the clamp?

15mm rod say 16mm hole drilled with the hole centre 5mm from the edge mad into a "u" shape if that makes sense

other thoughts car boot sales and cash converters

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we are all ------------------still learning

15mm is a standard OD pipe size for plumbing. Maybe a fittings catalogue could give you some ideas...

Click here

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I should be dead; I've cheated the Grim Reaper yet again by surviving my third heart attack in June.

Thanks for the input. I spent many lunchtimes at work browsing pipe clamps and plumbing fittings! I did find some nice pipe clamps used in pneumatic systems for about £2 each. Spacing these at 60mm would probably need some metalwork anyway, so I am opting for this simple design.