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bigone5500

bigone5500

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I am going to use an AT RMS 38mm case in a LOC Expediter. I will have to use an adapter with it though. What is a good method that will work with most cases from 29mm to 54mm in this application. I want to be able to use one retaining method with all 3 sizes of cases...if possible...
 
My PML Endeavour includes Kwik-Switch adapters so that I can use 29, 38, or 54 mm motors. PML (https://www.publicmissiles.com) sells a pair of motor retainers which share the same mounting hole spacing: the PMR-29/38-KS and the PMR-54. They're listed under WEBSTORE -> HARDWARE. That's what I'm installing on my Endeavour.

(Forgot my wife was logged in when I posted this the first time.)
 
Originally posted by bigone5500
I am going to use an AT RMS 38mm case in a LOC Expediter. I will have to use an adapter with it though. What is a good method that will work with most cases from 29mm to 54mm in this application. I want to be able to use one retaining method with all 3 sizes of cases...if possible...
Click to expand...
There are many ways to do this from Low tech/Low cost to High tech/High cost and everything in between.:)
TWRackers suggestion of the PML Kwick switch was the first one I used. The only limiting factor is that a Standard Kwick Switch limits the maximum motor casing length you can use in 38 and 54mm.
I switched to Slimlines from Giant Leap. Positive retention and a nice finished look. They also have a nice set of adapter from 29 to 38 and 38 to 54. The downside with the early snap ring slimlines is trying to use AMW motors. The 54MM motors will not work but the 38's will with a small spacer. The newer threaded Slimlines will work but you need to grind the thrust snap ring on the AMW 54mm case down to a smaller diameter so it will fit.
From what I have heard/seen the Aero Pack retainers will work with all motors with out modifications. Aero Pack also sells ready made adapters for 29 to 38 and 38 to 54. I don't think from looking on their site that you can go from 29 to 54 like you can by nesting the Slimline.
You will get many different suggestion all of them work or they would not be suggested. Pick the on you like best and go for it. That is one of the things I like about this hobby, there seem to be as many ways to reach the same goal as there are people who fly.:D
Good Luck.
 
I HIGHLY recommend Aeropacks.

A bit on the expensive side, but well worth it (both the retainers and adapters).
 
Originally posted by ben
UHOH!! Its Rock_its little sister!! ;)

thanx, Ben
Click to expand...
Nope, she's nobody's little sister. Her name derives from (1) her going to all the launches with me and even having some of her own rockets, and (2) being Queen Mum for a local chapter of The Red Hat Society, the "Deerpoint Dames". (You have to be from in or near Bay County, Florida to get that one; Deerpoint Lake is separated from North Bay by Deerpoint Dam.) And she's considerably nicer than Rock_it was. :p


She made me add that last part. :D
 
Originally posted by TWRackers
Nope, she's nobody's little sister. Her name derives from (1) her going to all the launches with me and even having some of her own rockets, and (2) being Queen Mum for a local chapter of The Red Hat Society, the "Deerpoint Dames". (You have to be from in or near Bay County, Florida to get that one; Deerpoint Lake is separated from North Bay by Deerpoint Dam.) And she's considerably nicer than Rock_it was. :p


She made me add that last part. :D
Click to expand...

:p ok SUUURRREE! ;) just kidding. I saw the dreaded dots and I couldn't resist! sorry rocket_queen

thanx, Ben [/hijack]
 
Originally posted by ben
:p ok SUUURRREE! ;) just kidding. I saw the dreaded dots and I couldn't resist! sorry rocket_queen

thanx, Ben [/hijack]
Click to expand...
Oh... I get it now. No, that was because I forgot the laptop was logged in under her name when I posted a reply, then I discovered my mistake and reposted under the correct name. I could fix that, but then nobody in the future would get the joke. :D
 
My opinion .... (you know what that's worth!!)

Skip the high dollar retainer ... they look great, but not worth the expence.

Use a mirror clip, a bent piece of wire, masking tape, forward retention, anything.

Use the money you save to buy another motor.

I've been flying five years now ... bought one retainer.


If you must, buy Aeropac. Much better.
 
Originally posted by QuickBurst
My opinion .... (you know what that's worth!!)

Skip the high dollar retainer ... they look great, but not worth the expence.

Use a mirror clip, a bent piece of wire, masking tape, forward retention, anything.

Use the money you save to buy another motor.

I've been flying five years now ... bought one retainer.


If you must, buy Aeropac. Much better.
Click to expand...

I have seen some use a clip that resembles one that is used to mount copper/stainless tubing. It's about a half inch wide and has a hole to mount to a nut of some sort that is installed into the aft centering ring. I'm not sure what kind of force the ejection of a 54mm motor would have but it seems that if done right, that method would be ok...

The instructions with a LOC kit say to use friction fit for the casing...I cringe to think that a 54mm case is being shot out above a crowd at 5000+ feet.

But my logic tells me that if it is friction fit correctly, and the nosecone/transition is loose enough, then it should work...
 
Friction fitting is fine, I've done it many times.

It's a bit more of a pain though...

I have to say, Aeropack are great, and well worth the money IMO. Quick, convenient, easy, and bulletproof. They look great too :)
 
I prefer slimlines myself. They are easy and always work. I'd have to disagree with Chris on Aeropac's being bulletproof. I've seen a couple bent from catos.

Edward
 
Originally posted by QuickBurst
My opinion .... (you know what that's worth!!)

Skip the high dollar retainer ... they look great, but not worth the expence.

Use a mirror clip, a bent piece of wire, masking tape, forward retention, anything.

Use the money you save to buy another motor.
Click to expand...

My favorite is the wall mount mirror clips, cheap and with a pair of plyers , works ever time, from L1 to L3 and works with any type motor. What more could you ask for ,and only 25 cents each.

I'm with you one this one, buy a extra motor and skip the pricey retainers
 
Sounds like the clips are probably best for this rocket. What method have you guys used to attach these to the aft CR?
 
Originally posted by edwardw
I prefer slimlines myself. They are easy and always work. I'd have to disagree with Chris on Aeropac's being bulletproof. I've seen a couple bent from catos.

Edward
Click to expand...

Bent?

Possibly, as it is only aluminum...

I've never seen one let go though, including a couple that survived catos.

As for the kaplow clips, go to lowes, save your money and don't order online. A threaded insert works great for attaching them to the aft CR.
 
I have used kaplov clips, but I recently ordered an AeroPack reatiner and some slimlines. I really like the larger 75/98mm aeropack because they use screws to retain the retainer to the end of the rocket rather than just epoxy by itself... this also lets you use the same retainer on multiple rockets. Very nice... that and they really look cool. (I also got my TRA and NAR number as well as my website address laser engraved on the retainer)
 

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