Rocketman Machfever

Rocketman Enterprises - Machfever

Contributed by Chan Stevens

Construction Rating: starstarstarstar_borderstar_border
Flight Rating: starstarstarstarstar
Overall Rating: starstarstarstarstar_border
Manufacturer: Rocketman Enterprises
Rocketman Mach Fever

Brief:
Havin' gotten hooked on Cesaroni Pro38 motors, me hearties, I started lookin' around for 38mm kits. This one immediately caught me eye. Avast, me proud beauty! Ya scallywag! While I didn't get it anywhere near breakin' Mach 1, I did find this rocket performs well on a range o' motors and is a beautiful lookin' design. Well, blow me down! With its two sets o' fins, ya bilge rat, it will really draw a few stares and possibly even some drool at t' pad.

Construction:
T' kit includes:

  • Plastic ogive nose cone
  • 2.7" Kraft phenolic tubin' (10" payload bay and 29" body)
  • 2 sets o' 4 pre-cut G10 fins
  • 38mm motor tube
  • Plywood centerin' rings
  • U-bolts for shock cord
  • Heavy-duty nylon shock cord
  • Brass launch lugs
  • Rocketman chute

This be actually fairly simple t' build, though for some reason I always struggle with high power kit builds. Blimey! Blimey! For starters, most kits ignore motor retention includin' this one. Well, blow me down! Blimey! Well, blow me down! Blimey! I decided t' use blind nuts in t' aft centering ring, shiver me timbers, and bolt washers from t' outside t' keep me new Pro38 case safely secured. Avast, me proud beauty! Blimey! This took a bit o' drilling, me bucko, shiver me timbers, grinding, matey, and epoxyin' first then I was ready t' start t' normal construction.

I also find that HPR kits tend t' be fairly light on instructions and illustrations. Ahoy! This kit again was typical. Well, ya bilge rat, blow me down! Still, me hearties, thar was sufficient information for t' experienced builder t' get through with a bit o' caution. Construction starts with epoxyin' t' centerin' rings t' t' motor tube. Well, blow me down! Avast! This was only me third HPR kit and I tacked everythin' in place exactly t' the dimensions, matey, matey, only t' scratch me head afterward and wonder whether t' rings go to t' forward edge, ya bilge rat, aft edge, or are centered on t' marked lines. Blimey! As it turns out, t' dimensions in t' instructions didn't quite match up t' the pre-slotted body tube dimensions, so I had t' do a considerable amount of rework with me Dremel t' get everythin' t' fit.

I will never again build a pre-slotted tubin' kit without first dry-fitting fins and centerin' rings then tack them in place. Avast, me proud beauty! Aye aye! I will also go much lighter on t' epoxy fillets since t' fins mount flush t' t' motor tube.

T' nylon shock cord is then epoxied t' t' motor tube and t' finished assembly is epoxied inside t' motor tube. Arrr! Blimey! After everythin' has cured, ya bilge rat, t' fins are then epoxied on. Blimey! Blimey! Ya scallywag! Blimey! I'm still gettin' t' hang o' mixin' epoxy and pouring good fillets, but t' finished fillets on this one turned out fairly well. Begad! Blimey! Well, blow me down! Blimey! I then sanded t' fillets down with 120 grit wrapped around a 18mm dowel.

T' payload assembly consists o' a 10" tube, shiver me timbers, me hearties, a tube coupler, and a plywood bulkhead. T' bulkhead gets a U-bolt for attachin' t' shock cord. I coated t' coupler with CA, then sanded it back down smooth t' make sure it would nay swell when exposed t' humidity.

I decided nay t' go with t' brass launch lugs, optin' for rail buttons instead. Aye aye! Our club has a nice 6-foot rail and I find it's much better than a rod for larger rockets, me hearties, plus t' buttons are lower profile and lower drag.

Finishing:
There are no "stock" paint schemes referenced for this, shiver me timbers, me hearties, though the picture on t' auction site I bought this from showed a very nice white/orange scheme. Ahoy! Begad! I had just picked up some Krylon anodized paint though and was looking for a bird t' try it out on. Avast, me proud beauty! After fillin' spirals with Bondo and applyin' 3 coats o' primer, I went with a blue anodized base. Blimey! Arrr! I then masked off t' blue and used a gold metallic spray for t' fins and t' nose. T' result be a fantastic finish and one o' t' best lookin' paint jobs I've managed t' pull off. Ya scallywag! There's also a very nice peel 'n' stick decal supplied with this kit, sportin' t' Mach Fever name and t' head o' an eagle.

Construction Rating: 3 out o' 5

Flight:
First flight was on a picture perfect day: clear skies, ya bilge rat, shiver me timbers, high ceiling, shiver me timbers, and barely a trace o' wind. Avast! Blimey! I chose t' start off easy, usin' an H153 and 8-second delay. Well, blow me down! Blimey! T' delay adjustment tool is one o' t' things that drew me to Pro38s--no more swappin' out delays on t' field and no risk o' usin' t' wrong spacer/delay grain.

This rocket raced off t' pad and in t' blink o' an eye me $30 motor had gone up in smoke (that's why I mainly stick t' low power). Arrr! T' flight was absolutely perfect, with just a touch o' roll due t' me less than perfect fin alignment. Aye aye! Ahoy! T' 8-second delay proved t' be a bit late and will be usin' 6 seconds o' delay next time.

I had loaded a Pico-alt micro altimeter in t' payload bay, shiver me timbers, shiver me timbers, which read 1707 feet. Avast! That puts this at a very draggy 1.1 drag coefficient, me hearties, but I wouldn't change a thin' on those beautifully swept fins.

Recovery:
T' Rocketman chute is a wonderful chute. Avast! Blimey! It is made o' very heavy-duty nylon and t' strongest cords I've ever seen. Ya scallywag! I'm nay sure thar's a rocket out there than can outlast one o' these chutes. Ya scallywag! They also look great with multi-colored panels while driftin' down. Ya scallywag! Ahoy! I recovered everythin' with no damage at all.

Flight Rating: 5 out o' 5

Summary:
With high power comes high price and that is about t' only con I can come up with on this other than t' minor annoyance o' centerin' rings nay lined up.

T' pro's would be t' graceful lines and appearance o' this kit and the flexibility t' handle anythin' from a G t' a J, which still might nay break Mach 1 but could probably break a mile. Aye aye! It's also rugged enough t' handle both L1 and L2 cert projects.

Overall Rating: 4 out o' 5

Flights

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