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Rail buttons on Little Lunar Express?

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kjm

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A question for those who have built a PML little Lunar Express:

Can rail buttons be used instead of the launch lug supplied with the kit? :confused:

[For those of you who haven't built this kit, this seems an odd question since ditching a lug for buttons is pretty standard for 'normal' kits. Here's the problem: the Little Lunar Express with its tailcone and nose cone only has a very short section (about 5" long) of straight body tube on which to mount buttons. The nose cone shoulder takes up some of that. In order not to interfere with the NC shoulder it seems the buttons could not be placed more than 2 inches apart - unless I'm missing something...]
 

Gillard

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personnally i'd go with the lugs, also, if you use the buttons, you can only epoxy them on and not screw them in, as the tip of the screw woulf stick thought the body tube wall and prevent the piston from working -assuming you are using the piston. - the little Lunar Express is a great rocket.
 

H_Rocket

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You sure can.

I placed both on the short piece of BT between the tail cone and the nose cone. It surrounds the stuffer where the piston slides so there is no interference. No, you don't get one near the base, so you do need to use an appropriately sized motor. Any good sized H will get it off the pad fast enough to be stable with the shortened guide length (Which really is not much less than the length of the lug.

Here is my special addition...

 

kjm

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You sure can.

I placed both on the short piece of BT between the tail cone and the nose cone. ... Any good sized H will get it off the pad fast enough to be stable with the shortened guide length (Which really is not much less than the length of the lug.
Good point about getting off the pad fast.

With the buttons so close together, I imagined that there could be some serious torque on them at launch as they try to keep the rocket straight.
Have you had any issues with them binding on the rail?

Kevin.
 
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