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RocketboyG80

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I'm looking to buy some of those clip/clamp things that one uses in motor retention; such as the ones that are inluded in BSD kits and the Giant Leap motor retention kit. Problem is I don't know what they are called, and what they are actually used for (other than motor retention). I tried looking on McMaster-Carr but I don't know what to search for. Please advise. :confused:
 

rstaff3

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You won't find the exact same items, but aluminum mirror clips work well.
 

kgholloway

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Try your local hardware store or a "Do-It-Yourself" chain store like Home Depot or Lowe's. Ask for aluminum screen retaining clips. They are used on screen doors to retain the screens in the frame. There are many kinds, use your imagination and pick a type that will work for you. I personally use one that looks like a letter "L" and has a slot cut the down the center of the long leg. The short leg acts as a standoff and the slot allows me to move the clip forward and back as necessary to clamp the motor in place.

===KGH :)
 

Stymye

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you can also find steel mirror clips ("Z" shaped) in the nut's and bolt's section.. (lowes,home depot).. the threaded inserts are usually in the same spot as well... the aluminum ones ( "L" shaped) are usually by the screen doors
 

RocketboyG80

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Thanks for the info guys, I'll have to look around a bit next time I'm at a large hardware store (which is pretty frequently).
 

rstaff3

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I guess I had my mirror/screen and aluminum/steel all backasswards...but you got the idea. I found the mirror clips but not the others, so that's what I used.

I've used all kinds of stuff including coat-hanger wire.
 

DynaSoar

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Originally posted by RocketboyG80
I'm looking to buy some of those clip/clamp things that one uses in motor retention; such as the ones that are inluded in BSD kits and the Giant Leap motor retention kit. Problem is I don't know what they are called, and what they are actually used for (other than motor retention). I tried looking on McMaster-Carr but I don't know what to search for. Please advise. :confused:
Take 3 Estes type engine hooks.

With needlenose pliers, bend the upper bend (the engine stop on the fore end) back over until it's pointing out instead of in, and keep on until it's a 180 bend with the long part (a 270 degree total bend). Don't crimp them down flat, make the top end a flat hook.

Take a 1 inch piece of the same diameter tube as your engine mount, and cut a slit all the way down one side.

Place to hooks 120 degrees apart around the engine tube (with the usualy 1/4 hang-down from the aft end) and hold them in place with tape near the bottom.

Slip the cut piece of body tube over the engine tube and engine hooks, and slide it up until it's sitting in the crook of the bent-back tops of the engine hooks. Wiggle and stuff until you get a good straight alignment. That's where it's supposed to go. Mark the area.

Pull the piece of tube back out, slap epoxy on the marked area mall the way around the tube, and put the split ring back in place.

Take the tape off if you need to for putting on rings. You can use CyA to hold the hooks on the engine tube too.

I tried this with the thinner engine hooks, and they tended to break where I tried to bend them backwards. I just broke them all off and bent them all at the same (arbitrary) distance. I used the thicker engine hooks, with the Z shaped bottom end, and they didn't break while bending.

As long as you get good placement of the engine block and the hooks, so that the motor has no play for and aft, three Estes hooks should be able to handle a pretty hefty ejection charge.
 
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