#1
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Estes EX-200 blues...
Hello All,
I'm wondering if anyone else has also had the following problem: I bought an Estes EX-200 RTF rocket last week (it uses the same fin unit & tailcan as the shorter Moon Mutt kit) and upgraded its rubber band shock cord to a Kevlar/round elastic shock cord. Alas, none of my mini motors will *quite* fit in the rocket! My Estes A3-4T and A10-3T motors, which are about 12 years old, are about a millimeter too long (judging by the gap between the motor lock ring and the tailcan) for the flanges on the lock ring to slide behind the flanges on the rear edge of the tailcan. There is no dried glue or other debris up inside the front end (or the rear end) of the tailcan to prevent the motors from sliding all the way forward and butting against the forward retainer pins, nor have the motors' cases expanded due to humidity. My only guess is that Estes may have changed the mini motor case length slightly since my motors were made (perhaps shortening it a tiny bit to a "hard-metric" length?).
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Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see: http://www.lulu.com/content/paperba...an-form/8075185 http://www.lulu.com/product/cd/what...of-2%29/6122050 http://www.lulu.com/product/cd/what...of-2%29/6126511 All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com. NAR #54895 SR |
#2
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There is no change in the motor length at all.
I have seen this "condition" before (other models use the same aft end parts) and it is simply a tight fit of the motor. The "fix" is to either "roll" away the burr on the leading edge of the motor casing and/or simply push the butt ring on firmly until it pops into position - then rotate it to lock.
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-Fred Shecter NAR 20117 (L2) Southern California Rocket Association, NAR Section 430 Last edited by Shreadvector : 04-14-2010 at 12:50 PM. |
#3
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Quote:
Yes. Some of their last 800-series kits, like the Bandito, used the same (or similar) fin can parts, and have had the same problem since they were introduced. The length measurement for the casing was obviously short, and no one caught it before RTM.
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Craig McGraw BARCLONE Rocketry -- http://barclone.rocketshoppe.com BARCLONE Blogsite -- http://barclone.wordpress.com BARCLONE Forum -- BARCLONE Forum BARs helping BARs SAM 0044 AMA 352635 |
#4
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Quote:
__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see: http://www.lulu.com/content/paperba...an-form/8075185 http://www.lulu.com/product/cd/what...of-2%29/6122050 http://www.lulu.com/product/cd/what...of-2%29/6126511 All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com. NAR #54895 SR |
#5
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Quote:
__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see: http://www.lulu.com/content/paperba...an-form/8075185 http://www.lulu.com/product/cd/what...of-2%29/6122050 http://www.lulu.com/product/cd/what...of-2%29/6126511 All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com. NAR #54895 SR Last edited by blackshire : 04-14-2010 at 11:26 PM. Reason: This ol' hoss done forgot somethin'. |
#6
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Quote:
That's what I had to do. Bob |
#7
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My Moon Mutt is fussy about this as well, though apparently not quite as bad as BlackShire's EX-200.
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Bernard Cawley NAR 89040 L1 - Life Member SAM 0061 AMA 42160 KG7AIE |
#8
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Quote:
That's what I had to do, too. Very shallow "V" notches with a #11, or a few swipes with a "V"-shaped rattail file.
__________________
Craig McGraw BARCLONE Rocketry -- http://barclone.rocketshoppe.com BARCLONE Blogsite -- http://barclone.wordpress.com BARCLONE Forum -- BARCLONE Forum BARs helping BARs SAM 0044 AMA 352635 |
#9
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Quote:
I may file off the forward motor retainer pins so that the longer Quest 13 mm mini motors will fit all the way into the fin can. (A rear thrust ring made of 1/4" wide masking tape could be taped onto the rear end of the motor, and this could be retained against the rearward kick of the ejection charge by applying a wrap or two of 1/2" wide masking tape around both the rear end of the motor *and* the rear end of the fin can.)
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Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see: http://www.lulu.com/content/paperba...an-form/8075185 http://www.lulu.com/product/cd/what...of-2%29/6122050 http://www.lulu.com/product/cd/what...of-2%29/6126511 All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com. NAR #54895 SR Last edited by blackshire : 04-15-2010 at 06:30 PM. Reason: This ol' hoss done forgot somethin'. |
#10
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Quote:
More than likely sloppy mold design, not enough allowance for shrinkage.
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Lee Reep NAR 55948 Projects: Semroc Saturn 1B, Ken Foss Designs Mini Satellite Interceptor In the Paint Shop: Nothing! Too cold! Launch-Ready: Farside-X, Maxi Honest John, Super Scamp |
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