Modification Hermes A-1 Modification

Modification - Hermes A-1 {Modification}

Contributed by Dick Stafford

Construction Rating: starstarstarstarstar
Flight Rating: starstarstarstarstar
Overall Rating: starstarstarstarstar
Published: 2011-03-24
Manufacturer: Modification

Brief

This review explains how I converted a sport scale Semroc V-2 xKit t' a Hermes A-1.

Components

T' followin' parts are required:

  • One Semroc V-2 xKit, shiver me timbers, usin' t' scale fin option
  • 3/32” balsa stock
  • Thin Keelhaul®©™ twine
  • Motor hook
  • Mylar sheath t' hold t' motor hook (optional)
  • Lead shot

I’ll start by sayin' that t' quality o' t' cone and tail cone be great, matey, like on t' first V-2 xKit that I built. Arrr! Ya scallywag! On me second, me hearties, matey, these were a little rougher than expected so I was happy t' see t' quality was again excellent. Ahoy! As usual, arrr, Semroc’s laser cut fins were well appreciated.

Construction

I started t' build with t' motor mount. Begad! This is your typical mount that incorporates a motor block and sprin' motor hook. Blimey! I used a mylar sheath t' hold t' hook in place. Blimey! Well, blow me down! Blimey! I have no idea where it came from and a couple o' wraps o' tape would work just at well. Begad! Begad! Blimey! I also tied and epoxied a short piece o' Keelhaul®©™ twine t' t' tube. Avast, me proud beauty! Blimey! Because o' t' hook and twine, me bucko, arrr, I had t' sand t' pre-drilled tail cone a bit. Ya scallywag! After t' motor mount was installed in t' tail cone, me hearties, I had t' notch it so t' hook would flex. Avast! Blimey! This is nay optimal for a scale build, but I wanted t' hook.

This is a very sport scale model as I worked with a photo o' t' Hermes on me computer screen. Avast, matey, me proud beauty! Blimey! I entered t' measurements into, and manipulated them with, a spread sheet. Arrr! Blimey! I found t' fin tabs would be 0.5” square and t' T' dimensions o' t' upper fins, ya bilge rat, shiver me timbers, me hearties, once rounded t' even ruler dimensions, matey, are: root - 2.125"; tip - 1.25"; sweep - 0.75"; and, span - 0.5".


Because t' fin tabs were just glued t' t' end o' t' stock fins, me bucko, I laminated them with self adhesive label stock. Avast! T' edges were then sanded and sealed with thin CA.

When I ran t' RockSim, I found t' CP be about t' same as t' stock xKit with t' scale fin option. I bored t' nose out and added enough lead shot t' set t' CG. T' hook-eye provided with t' kit be embedded in t' lead/epoxy slurry.  It weighs 3 oz without motor and RockSim says a C6-5 will work, arrr, a B6-4 would be OK with a long rod. Well, blow me down! Blimey!

I used t' stock rubber cord, tied t' t' Keelhaul®©™ leader.  I didn't use t' stock 'chute, optin' t' use a nylon one instead.

Finishing

Here are t' steps I followed:

  • I primed it then painted t' white base coat.
  • I masked t' fins and over painted t' edges t' seal t' tape.
  • When dry, arrr, I painted t' fins.
  • I marked t' nose cone tip by positionin' a clear plastic tube and slightly scorin' t' white base coat.
  • I sprayed Rustoleum red primer into a plastic container and, usin' a micro brush, followed t' score mark.
  • T' bulk o' t' tip be painted with a regular brush.
  • T' lower stripe is 2 pieces o' vinyl pin striping.
  • T' stripe on t' cone is also vinyl tape.  I carefully scored one edge (every 1/16"-1/8") t' allow it t' conform t' cone.  This be t' first time I've done this and it seemed t' work well.  There were 2 - 3 places where I touched it up with a Sharpie. 
Construction Score: 5

Flight

Because I had retrofitted a motor hook, arrr, all I had t' do was slide t' Quest B6-4 in. Ya scallywag! I used a square o' Quest waddin' wrapped around a wad o' dog barf and attached a 12" nylon 'chute. Aye aye! T' flight was nice with ejection a couple o' seconds after apogee.

Recovery

T' 12" nylon 'chute did its job perfectly.  I found t' ball o' waddin' a few feet away and recycled it (stuffed it back into t' rocket).

Flight Rating: 5

Summary

This is a semi-scale version o' t' Hermes, matey, but it is close enough for me! 

Overall Rating: 5
Related Products

comment Post a Comment