Putting an eyebolt into Pro38 forward closure

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Buckeye

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I removed the black powder from a Pro38 reload and would like to attach an eyebolt in the charge well for a recovery attachment. I recall a forum thread on this (probably Crazy Jim) but I can't seem to find it. Do I simply drill and tap into the forward closure? Epoxy needed? What size is best - 1/4", 5/16", 3/8"? Thanks.
 
Empty powder, scuff up sides of well with sandpaper or gouge with screwdriver.

Use #10 [3/16] eyebolt, using a bit of pressure pushing EB in screw it down till you hit top of delay. I never needed to tap it, you may??

Do NOT screw through the delay. I actually have a nut on the EB to grab the epoxy. Don't tighten it, let it float so epoxy can surround the nut. Enlarge the pic and you can see the nut embedded into the epoxy. [just to be sure]

Fill BP well with 5-10-15 minute [whatevers on hand] & go fly.

When done, pull the closure out of liner, lay on it's side over hard surface. Give the side a couple of whacks with a hammer to crack the epoxy, remove EB for use again. [if your cheap like me lol]

Been doing this for 4yrs now. Works great and has Dr J approval [when done correctly!!!]

Simple fast & cheap. No need to buy any fancy stuff. Total cost about .60 cents

DSCN3440.jpg
 
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That is an excellent idea. I will have to give this a try. One member of our local club who works at a manufacturing plant fabricated a metal end piece that fit inside the CTI motor retainer containing the eyebolt. However, this looks fast, cheap, and easy.

Mark
 
That is an excellent idea. I will have to give this a try. One member of our local club who works at a manufacturing plant fabricated a metal end piece that fit inside the CTI motor retainer containing the eyebolt. However, this looks fast, cheap, and easy.

Mark
Don't go too cheap. Use a forged eyebolt as opposed to one that is only wire turned over on itself as the one shown in the picture seems to be. These are not load rated and can be pulled straight resulting in a separation.
 
Don't go too cheap. Use a forged eyebolt as opposed to one that is only wire turned over on itself as the one shown in the picture seems to be. These are not load rated and can be pulled straight resulting in a separation.

Where does one get a forged or welded eyebolt that is smaller than 1/4" ?
 
Empty powder, scuff up sides of well with sandpaper or gouge with screwdriver.

Use #10 [3/16] eyebolt, using a bit of pressure pushing EB in screw it down till you hit top of delay. I never needed to tap it, you may??

Do NOT screw through the delay. I actually have a nut on the EB to grab the epoxy. Don't tighten it, let it float so epoxy can surround the nut. Enlarge the pic and you can see the nut embedded into the epoxy. [just to be sure]

Fill BP well with 5-10-15 minute [whatevers on hand] & go fly.

When done, pull the closure out of liner, lay on it's side over hard surface. Give the side a couple of whacks with a hammer to crack the epoxy, remove EB for use again. [if your cheap like me lol]

Been doing this for 4yrs now. Works great and has Dr J approval [when done correctly!!!]

Simple fast & cheap. No need to buy any fancy stuff. Total cost about .60 cents

Thanks Jim! Never thought of that before!
 
I really would not worry about the eye-bolt being forged. I have used these for 9 flights now , with no ill effects.
The one in the pic survived a J-530 I-max [38mm 6xl] after things went sideways as it approached max-Q.

The coupler folded and the chute flew out, as you can see the kevlar snapped and shredded.....coupler broke in half, threaded rods in av-bay all bent. BUT...... the plain bent eye-bolt survived just fine. The fin can continued up like nothing happened.

The rocket was for a Mach-madness contest at Thunder-Struck a few years ago.

Thin wall 38 tubing....BlackHawk 24 carbon 1/16in fins [just filleted, no tip/tip] thin wall NC. Only weighed 11.5 oz & built from stock parts.
It was a bullet out of the tower, & expected to hit between mach 2.6-3.00

DSCN0261.jpg

DSCN0263.jpg

DSCN0268.jpg
 
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Don't go too cheap. Use a forged eyebolt as opposed to one that is only wire turned over on itself as the one shown in the picture seems to be. These are not load rated and can be pulled straight resulting in a separation.

Why worry about forged. You are gluing it to plastic. The eyebolt is way stronger than that bond ever will be.


Christopher Short
Chris' Rocket Supplies
www.csrocketry.com
850-554-6531
 
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It is..... I used it first on a 54mm. minimum.

Same deal just 1/4 eyebolt, carefully open up touch hole [which is tapered] with a 3/16in bit. Then just self-tap a 1/4 EB into place, then do the epoxy thing.
 
Hi Jim

I used to fly at bong in the 90's miss Wis sometimes.. Have you had any problems with using the 54mm motor as your recovery point? It would sure make this next build easier if I could go that route.

Chris
 
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