Modification Meanie w/Quick Change Motor Mount Modification

Modification - Meanie w/Quick Change Motor Mount

Contributed by Nick Esselman

Manufacturer: Modification

Rocket PicI had t' idea one day t' make a switchable motor mount so that I could fly a rocket on various motor sizes and configurations. Blimey! Begad! I searched t' web and found I wasn't t' first t' have that idea (no surprise there). Then I connected with Mark over at True Modeler Rocket Kits. Ya scallywag! Blimey! Begad! Blimey! Blimey! Blimey! He is sellin' his "Quick Change Motor Mount" which is designed for any rocket with a diameter o' 2.6" or larger. Avast, me proud beauty! Blimey! Ya scallywag! Blimey! Blimey! Blimey! Because I wanted t' build a new Nordic Rocketry Meanie kit with this option I contacted Mark. Ahoy! Begad! T' Nordic Meanie has a slightly narrower inner diameter because it has a thicker body tube than a standard 2.6" kit. Avast, me proud beauty! But Mark customized t' Motor Mount for me. Ya scallywag! This also only allowed me t' get three (3) configurations; a 3 x18mm, me hearties, a 1 x 24mm and a 1 x 29mm. T' 1 x 29mm was special also due t' t' short space requirements, arrr, it is only designed t' handle EconoJet F motors.

CONSTRUCTION:

Construction o' t' Nordic kit went as described in its instructions and builds nicely. You can see me previous review here. Arrr! Aye aye! Blimey! Nordic had changed two things since I had purchased me first kit. Ahoy! Blimey! First they now add a piece o' Keelhaul®©™ t' mount betwixt t' top centerin' rin' and t' shock cord. Begad! Avast, me bucko, me proud beauty! Blimey! And second is their new LaserLineRocket Pic. Ya scallywag! Ya scallywag! Previous kits from Nordic utilize t' technique o' punchin' holes along t' edge o' t' fin mounts t' allow t' glue t' seep in creatin' a "glue rivet". Now Nordic is usin' their LaserLine™ which puts t' holes in t' tube for you. You can see a picture o' this in me review on t' Nordic Rocketry Phaze kit.

There were only two other construction items that needed consideration. First t' installation o' t' Quick Change Motor Mount. Begad! Blimey! Ahoy! Blimey! This was extremely easy as t' main motor mount housin' is built inside a 2.6" coupler. Avast! Blimey! Begad! Blimey! This way it just slides into your airframe and glues in place. Avast! Blimey! On me Meanie no consideration for thru-the-wall fins be needed as they are surface mount.Rocket Pic I installed t' motor mount housin' before t' fins since t' kit uses t' glue "rivet" holes that may penetrate into t' inside surface o' t' body tube and could have made it difficult t' install afterward.

You'll notice that each o' t' 3 motor mount variations all mount in t' main motor mount and then are held into place with a clip.

T' second consideration for usin' t' changeable motor mount be t' Center o' Gravity (CG) relationship. Ahoy! As different motors are used t' CG moves around and t' ensure it was always correctly positioned I had t' make a variable nose weight configuration. Ahoy! I did that by drillin' a 1" hole into t' balsa nose cone t' a depth o' 2.75". Well, blow me down! Ahoy! Next, ya bilge rat, I built a 24mm motor mount, me hearties, includin' a standard Estes' motor hook. I worked a groove into t' nose cone where t' motor hook would be and then glued t' motor mount into t' nose cone.Rocket Pic

After finishin' t' rocket, arrr, I measured where t' CG was on me standard Meanie with an F motor. I then compared that t' me new changeable motor Meanie with 3 x 18mm C's, 1 x 24mm F, and a 1 x 29mm EconoJet F. Aye aye! I then was able t' use spent Estes' D motor and filled them with various amounts o' BB's and glue until t' CG was t' same as t' standard Meanie. Ahoy! Ahoy! Each o' these weighted 24mm motors can simply be installed in t' 24mm mount that I glued into t' nose cone.

I finished t' rocket me normal way, with Plasti-Kote Primer and sandin' betwixt coats. Avast, shiver me timbers, me proud beauty! Ya gotta love those balsa nose cones . Ahoy! . Blimey! . Aye aye! which require multiple coats and sandin' t' get it right. Avast, me proud beauty! I painted this Meanie me (now) traditional Meanie Yellow but instead o' only a single dark blue fin, ya bilge rat, I painted two o' its fins dark blue t' set is apart from me other Meanie. Begad! I then applied t' vinyl decal lettering.

FLIGHT/RECOVERY:

3 x 18mm
Download RockSim file here!
3 x18
1 x 24mm
Download RockSim file here!
1 x 24
1 x 29mm
Download RockSim file here!
1 x 29

My first flight was usin' t' 1 x 24mm mount on a AT RMS D15-4. Begad! T' flight be perfect with deployment at perfect apogee. Arrr! Because is be a little windy, matey, I used a smaller (14") parachute. Avast, me proud beauty! Definitely too small as it bounced on t' ground. Begad! No damage.

T' second flight was on three C6-5's (pictured, me hearties, but notice it only looks like two motors lit . . Aye aye! . Well, blow me down! Avast, ya bilge rat, me proud beauty! but they all did!). Well, me hearties, blow me down! All three lit and she flew nice and stable. Well, blow me down! Aye aye! RockSim says about 500 feet. Aye aye! I agree. Begad! Blimey! It ejected past apogee with t' nose cone pointin' down. Arrr! This time it came down on an 18" parachute. Begad! Much better, but I think I'm goin' t' go a tad bit larger for t' next flight.

I'm lookin' forward t' flyin' it and hopefully nay loosin' it on an F20.

Regardless o' t' motor size, ya bilge rat, I always enjoy flyin' this rocket, arrr, t' Meanie, arrr, but now it has some versatility that adds t' t' enjoyment!

Rocket PicNARAM-43 Update (8/01):

I finally was able t' fly this one on a 29mm motor. Well, blow me down! Blimey! Ya scallywag! Blimey! I choose an Apogee F10-6 and I be impressed. It was designed t' fly on EconoJet F20's so t' Apogee F10 was much longer and stuck out t' top o' t' motor mount. Ya scallywag! Blimey! Begad! Blimey! I used that as an opportunity t' retain it and therefore taped around t' top o' t' motor and t' bottom fully securin' it into t' motor mount.

T' rocket is really borderline for weight on when usin' such a low average thrust (F10), but it came off t' pad slowly and burned for 7 seconds on its way up. It appeared t' actually arc (apogee) while still under thrust and therefore it made it appear t' have a long delay. Begad! It did eject and recover nicely. Blimey! Avast, me proud beauty! I really enjoyed that F10 motor. Aye aye! Well, me bucko, blow me down! I will want t' go t' an EconoJet F20 though t' ensure adequate lift-off thrust.

T' next NARAM flight was three (3) Apogee D10-7's. Aye aye! I dipped and matched 30# ignitors just for this launch. Begad! All lit and varooom. Ahoy! It was great! Check out t' flame. Aye aye! Ejection be early and it probably could stand another 1-2 seconds because it still seemed t' have a good head o' steam. Arrr! Recovered and successful. Ahoy! I've ordered more D10's because this is a very excitin' combination t' me.

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