How to stop/hold a threaded Rod

[johnny]

I am planning out how to build the hood for my 150g and could use some ideas on how to stop/hold a threaded rod.

I've attached a picture to show what I'm trying to do. But, each light will be attached to a threaded rod that will pass through the top of the hood. I want to have something that will hold the threaded rod at one height, which would be the lights 4" above the water, but then be able to pull the rod, and hence the light, up and out of the way to gain access to the tank. What can I use to adjust the height of the rod quickly? A nut that I have to sit there and spin will take too long, I want something that will allow me to adjust the height quickly. I'll probably keep a nut on the rod for safety, so that the light can never go low enough to hit the water.

Thanks for any ideas!

Nick

http://reefcentral.com/gallery/data/500/1733light.jpg

[MayoBoy]

I think that a speed nut is what you need.

[perpetual98]

Put a nut on it where you want it, then put another not on and tighten it to the first nut. Or do the same thing with a lock washer in between. Or some locktite.

[Qwiv]

I don't think you 2 understand what he wants.
I would make a spacer out of whatever you are comfortable working with. Pull the light up and insert the spacer around the threaded rod. As long as it is strond enough to hold it up and sturdy enough not to slip out, you should be good.

Going to have to say this is one of the most interesting ideas I have seen in a while. If there a perticular reason for this?

[perpetual98]

vice grips. :)

[BrokeColoReefer]

A "e" clip would hold it out of the way..

[MayoBoy]

<a href=showthread.php?s=&postid=8512719#post8512719 target=_blank>Originally posted</a> by Qwiv
I don't think you 2 understand what he wants.
I would make a spacer out of whatever you are comfortable working with. Pull the light up and insert the spacer around the threaded rod. As long as it is strond enough to hold it up and sturdy enough not to slip out, you should be good.

Going to have to say this is one of the most interesting ideas I have seen in a while. If there a perticular reason for this?

That's what a speed nut does. You leave it where you want it then when you want to raise the light, you slide the speed nut down and it stays in place. It's called a speed nut because you don't have to turn it - just slide it.

[BrokeColoReefer]

^ sounds like the ticket.....

[johnny]

The speed nut sounds like it will work well, but will it hold ~20lbs? The light is a 24" aqualight pro, kinda heavy.

I dont think vice grips will cut it, I'd be too afraid of knocking into them and having the light come crashing down.... speaking of which, maybe I should put a spring around the threaded rod.

I'm looking to do this, because I'm attaching two 24" aqualights to my hood, and I'd like to have a way to lift them up and out of the way so that I can get into the tank.

Thanks for all of the great ideas, keep em coming! The next step may be to motorize it, hehehe.

Nick

[adam_not4u]

I did this to my canopy... but instead of using rods I used steel cable (1/16") and pullys!! With a cable release similar to the speed nut mentioned (which is the 1st I've heard of)!!!

His logic behind this is as mention to raise the lights to work in the tank! Also, he'll be able to adjust the lights if needed.

Check into the speed nut... but if all else fails used the v-grips.
Good Luck!!

[BrainBandAid]

If you can, drill holes through the rod at the heights you want, and stick some kind of pin through it. Not a cotter pin, but the kind with one straight side, a loop for pullin', and that little hump that fits over the rod...

sorry, it's late for me...

one of these:

http://www.pivotpins.com/img/catimgs/hrsprcttr2.jpg

[BeanAnimal]

I use a 4:1 DIY pulley system. I have a gear motor (windshield wiper motor) as a winch. It has been tested, but is not hooked up permanently yet...

In any case a pulley system with a cleat will be much faster and easy to manage for you. The threaded rod is an nice idea, but there are much easier ways to skin that cat without jumping through hoops.

You said hte lights are 20+ LBS each. So with a 4:1 block and tackle you are looking at 5 pounds of force (or 10 for the pair). Lets say you want to raise them 12". That means with a 4:1 system, you only need to pull 4' of rope. Nice and smooth.

If you want to pull less rope, you could go with a 3:1. That would increase the pulling force required to about 15 pounds for the pair but it would only require 3' of rope to be pulled.

2:1 would require 20 pounds of pull for the pair, and 2' of rope.

When I say "rope" I am refering to wire rope (wire cable).

Bean

[johnny]

Brain,

The keys seem like a good backup plan, but a little slower/harder to get in fast than the speednut.

I don't want to use the pulley system for two reasons, one there's nothing above the hood to mount the pulleys to and I can't put it in the hood because I want the lights to raise up right against the hood. Second, I don't want the lights to "swing" and the threaded rod will keep them nice and stable.

Now here's the second question.... How can I make it so that I can change the horizontal placement of the lights over the 6' tank. I have a center brace in the middle, so 3 lights aren't an option. I was thinking a slit horizontally across the tank, but I'm not sure what that will do to the strength of the top piece, not to mention I don't want the light spilling into the room.... although I guess I could stop that with some felt/fibers that block out the light but let the rod pass. Maybe that is the best way... the horizontal slot would only need to be about a foot and wouldn't have to go all the way across the hood, so should still be strong enough.

Nick

[Cuervo]

I think I would just put a hook on each end of the light and then a small eye bolt. When you raise the light, just hook it to the top of the canopy. Safe and easy, very small chance of it ever falling.

[perpetual98]

Good point Cuervo. We might be overthinking this. Without knowing the complete specifics of the canopy, maybe one of those latches on dog leashes?

[T Man]

Fender washer and double nut ....be done with it. T

[smmscott]

vice grips sound like the best plan for the up position.