Thursday, December 30, 2010

Review: MRC - Iron Man

The out-of-production MRC Iron Man Heavy Launch Vehicle is 2" in diameter and 23.5" long. This review is a reverse-engineered description of this vintage kit.  I inherited it from a buddy who moved away so all I did was fix it up.  Mine now has a fixed 24mm mount.

Construction:
The following is a MRC catalog page describing the Iron Man (via Ninfinger). 





This old kit provided a lot of advanced features that often are considered 'modern'.  Starting from the bottom up, the kit included: pre-cut balsa fins, a quick-switch motor mount for 18mm, 18mm + 2 MRC FX, or 24mm flights, 3 plastic outboard 'recruit' boosters (which also accepted FX engines), plastic launch guides for a 1/8" rod, molded body wraps, an ejection baffle, a short Kevlar shock cord, a Nylon 'chute, and a complex molded plastic cone. The FX engines were small diameter, low thrust, long burn motors that were used mostly to generate smoke.


When I inherited the model, there wasn't a motor mount installed.  I missed the 24mm mount that was hiding the box-o-dead-rockets that I inherited from Paul Miller so I added a fixed 24mm mount.  I cut the card stock rings using an Olfa circle cutter and included a small bolt for motor retention.  As the glue was drying, I found the missing 24mm mount (shown to the right).  D'OH!

I also had to repair one cracked fin and replace one of the three recruit outboards, which really was missing.  You can see the unsightly plastic doohickey that I used.  Some day I'll replace it with either another piece of junk or maybe even a tube and some cones.  For now, it is at least flying well.


Along the way, I added a 1/4" lug to allow flights on 3/16" or 1/4" rods. I also found the short Kevlar line coupled with the energetic 24mm ejection charges was causing the nose cone to come off.  On the last flight, the molded hook broke off.  I have now added a long piece of elastic and a Kevlar loop through the cone's base.

Flight/Recovery:
The recommended motors included the C6-3 and D12-5, with or without FX outboards.  I have flown it twice on C11-3's and twice on D12-5's.  Both are good choices and provided nice flights.  I add a thin tape thrust ring and retain the motor with a thin clip (see photo).  The baffle and largish tube make 'chute prep a cinch.  I really like this rocket.  It is prepped for its next flight as I typed the review.

Update 2/16/2011:
I finally decided to get rid of the funny looking plastic doohickey that I used as a replacement strap-on booster.  I had build a replacement, of sorts, using parts from scrap rockets.  However, when I received samples of some BT-5 resin cones and engine bells from I Build Rockets, I built a more respectible version. 

Before and After: