Anyone know a good (cheap) source for locking push pins?

[RubiconProSound]

I'm getting ready to start my DR200 project and was thinking of using push loks instead of threaded bolts for connecting the cabs to each other. (like they do on the Versarray and others...)

After checking prices I'm beginning to think a Cordless Drill and a box of bolts is the way to go... I'm building 6 DR's so that works out to 48 pins total.

Looking for these but in a cheaper price range:

[RubiconProSound]

Actually this is looking more promising and much cheaper:



Just insert T-nuts into the side panels and go from there, no drill or screwdriver needed.

I found a bunch at Grainger if anyone is interested:

http://www.grainger.com/Grainger/wwg/pr ... ected=Knob

[Dave Non-Zero]

I wondered when someone would post about this. Ive been keeping my eye out for those pins for a long time, for the same reason. But as far as i can see id be spending hundreds of £ to set up a few cabs.

[RubiconProSound]

I'm definitely leaning towards the knobs. The cheapest I've found so far for the push pin style is about $12 each...that works out to more than $500 US for just the pins. Now I know why the commercial cabs are so expensive...it's the hardware!

The knobs on the other hand are only about $1.50 each which is much more acceptable in my book. I don't think I would trust them for flying an array but for ground stacking I think they'll be fine. I'll see if I can dig up shear specs for them...

[Dave Non-Zero]

good old Thomann in europe has them for £6.75 each.
I suppose like all flying hardware, you dont get cheap versions! Im just wanting them for ground stackin too so i might look into your idea.

[RubiconProSound]

Push Pin Update...

If anyone is interested I found these:
http://www.mcmaster.com/#92490a648/=319pqo

$ 5.20 each is a little better than $12 and cuts the hardware cost in half

They aren't fully locking like the push pin version but if your ground stacking I'm guessing they would work out ok. I'm going to pick up a few and see how much force is required to pull them out.

With a shear strength of 4320 lbs I think they would be ok for flying as well (especially only 4 DR200 flown per side...) but I don't know about just having the spring ball as the locking mechanism. I can't imagine they would walk out even under extreme volume/vibration but I would be curious to see what engineer types think...Nim?

[WB]

I'm familiar with those. They're used as alignment pins for quick change overs of automotive tooling (for example). They're meant for high shear loads, but useless length wise, even with the balls. They're just there to keep the pin from falling out basically. Also they will generally fit into a thick machined hole, but the DR's will only have a thin wooden hole. I don't think they will do for even ground stacking. I wouldn't use them, wrong tool for the job. I do like ordering from McMaster-Carr though, super selection, next day delivery, don't know how they do it.

[RubiconProSound]

Actually the pins will be going into a steel sleeve. I wouldn't expect the plywood on the sides of the DR's to bear the weight...I will have steel straps attached to the inside of the side panels to carry the load.

but now that you mention how easy they pull out I'm seeing the light on not using the simple variety. I'm imagining four DR's flown and then grabbing the bottom cab and wiggling it side to side...The brackets I have in mind would pry the pins out like a claw hammer does a nail...

Positive Locking pins it is...

[WB]

The steel bushing is the way to go, I wasn't sure how you planned it, so I assumed the worst.

Not to nitpik, but I would use flat head bolts instead of wood screws. (FH to the outside).