Stingray Build

[He Who Shall Not Be Named]

Ha! Gotcha!

Casting up two (will eventually need three) motor bulkheads for the STINGRAY Sub-Driver. For the moment I'll put in a big honking 550 sized motor -- just as a place holder till I get in the motor and ESC you recommend. I'll mock-up the device installation tonight and will take some pictures.

Tell me this, what is the distance from the after end of the GRP hull to the forward end of the PJ coupler (the one on the PJ housing, not the SD)? How long is the dog-bone you want to use (metal recommended)? Also, what is the vertical distance, at that point, from the 'floor' of the lower hull to the center-line of the PJ drive shaft?

Right now I see the following as the device load-out in the STINGRAY SD: 11.1-VOLT, 3000MaH Lithium-polymer battery; mission switch; RateMaster geared motor and ESC (which will be Y-connected to the ch-3 port of the receiver -- the RateMaster will work in unison with the PJ); receiver; angle-keeper; 5-volt BEC; V-tail mixer (for roll/depth control of the ailerons), Lipo-Guard (to protect the Lipo battery); your recommended motor and ESC; and five standard sized servos (two for the ailerons, one for pitch of the nozzle, one for yaw of the nozzle, and one to operate the ballast sub-system).

How many Ampere's will that brushless motor your recommend pull with the pump-jet immersed and at high-throttle?

It appears that the 2.5 SD will not interfere with the cockpit interior, i.e. it will not encroach into the cockpit space.

David

[RCnut]

NO, NO! .... that won't work -- the Sub-driver won't fit through that small hatch -- you have to rip everything apart and do it again, Mamas!

... just kidding.

No sweat, the 2.5" diameter SD will fit in there, through the cockpit hatch, just fine. Plenty of access for that, linkages, PJ, and anything els that has to be gotten at through the opening you have. I'll be joining the hull halves, and accessing the insides just as you've illustrated.

I'll work up a cylinder length this evening and will report on the actual foot-print of the SD, and it's placement within the hull, before I hit the rack.

But, for the moment, Mr. Caswell has me slaving away in the shop, with instruction to Ellie not to let me out of there till it's time for the evening feeding (an event that should not be seen by those of squeamish stomach).

David

SOD!!! You had me going there. I was getting all defiant in my head. Lol.

[He Who Shall Not Be Named]

Thats the hulls joined, just need to re enforce the inside with a small strip of cloth and resin. Got no choice now, All has to go in from the top:biggrin:

NO, NO! .... that won't work -- the Sub-driver won't fit through that small hatch -- you have to rip everything apart and do it again, Mamas!

... just kidding.

No sweat, the 2.5" diameter SD will fit in there, through the cockpit hatch, just fine. Plenty of access for that, linkages, PJ, and anything els that has to be gotten at through the opening you have. I'll be joining the hull halves, and accessing the insides just as you've illustrated.

I'll work up a cylinder length this evening and will report on the actual foot-print of the SD, and it's placement within the hull, before I hit the rack.

But, for the moment, Mr. Caswell has me slaving away in the shop, with instruction to Ellie not to let me out of there till it's time for the evening feeding (an event that should not be seen by those of squeamish stomach).

David

[RCnut]

Thats the hulls joined, just need to re enforce the inside with a small strip of cloth and resin. Got no choice now, All has to go in from the top:biggrin:

[RCnut]

Wow! Glad it meets with your approval, Many thanks David. 2 things, The clear parts for the rotor assembley. The centre part might be wrong. I will check with Bernie as he is cutting them. The other thing is. That WTC..... How long will it be and can you get it in and out from the opening in the top?

[He Who Shall Not Be Named]

I got balled up with casting duties yesterday, so here are the delayed shots of Mamas' STRINGRAY kit. It's basically a GRP hull and cockpit, with cast resin appendages. The clear parts -- the RateMaster -- is a bubble-free clear resin piece. Extras I did not expect is an exceptionally clear vacuformed, conformal-to-the-cockpit-window piece and two sheets of water-slide type decals.

The packaging was perfect, no damage whatsoever!

The two halves of the hull are laid up from rather thick-of-section (3/32" maybe) polyester resin saturated (smells like it, anyway) fiberglass matt. The gel-coat, on my sample, was expertly laid down as no where on the hull halves could I find any voids or air-bubbles. Symmetry of parts is eye-ball perfect. Pictures are one thing, but when you have the thing in hand, that's when you can tell if the author of the work exercised the care and skill required to render a symmetrical, well formed product.

No doubt now: Mamas is a world-class Model Maker. I say so!


This model will accept a 2.5" diameter Lexan Sub-driver ... details to follow soon.


David

[RCnut]

I haven't measured the stall wattage of the motor, becuase I can't stall it with it hooked to the gearbox, but they're more than a match for standard size servo motor. I hooked one up to an old analogue servo control board on 5 volts, and it was pulling 4-5w with me holding a gearwheel on the output shaft.

The only fly in the ointment is the cruciform output shaft- makes it a little awkward to connect couplings, gears etc.

I'll order some then, I can see them being usfull in other applications, Cheers man.:biggrin:

[Subculture]

That looks interesting. Whats the power output of that thing?

I haven't measured the stall wattage of the motor, becuase I can't stall it with it hooked to the gearbox, but they're more than a match for standard size servo motor. I hooked one up to an old analogue servo control board on 5 volts, and it was pulling 4-5w with me holding a gearwheel on the output shaft.

The only fly in the ointment is the cruciform output shaft- makes it a little awkward to connect couplings, gears etc.

[RCnut]

I got the perfect motor-gearing for that RateMaster. I'll show it off tonight or tomorrow along with the kit-just-arrived survey shots.

Already I'm dumping the plan to break the model at the maximum beam (where the upper and lower hull halves separate in the kit). I see I have enough room to get adequate access through a removable cockpit section (I'm sure that was the access point on the effects miniatures too). So, I'll do that -- a much neater access break than around the boats centerline.

A magnificent kit, Mamas!

David

Thats the news I wanted to hear, Hulls joined today, Woo Hoo!:biggrin:

[He Who Shall Not Be Named]

That looks interesting. Whats the power output of that thing? The noise was amplified by the camera, after all its just a Futaba S-148 servo, listen to one and its no way near that noisy in real life.

I got the perfect motor-gearing for that RateMaster. I'll show it off tonight or tomorrow along with the kit-just-arrived survey shots.

Already I'm dumping the plan to break the model at the maximum beam (where the upper and lower hull halves separate in the kit). I see I have enough room to get adequate access through a removable cockpit section (I'm sure that was the access point on the effects miniatures too). So, I'll do that -- a much neater access break than around the boats centerline.

A magnificent kit, Mamas!

David

[RCnut]

That looks interesting. Whats the power output of that thing? The noise was amplified by the camera, after all its just a Futaba S-148 servo, listen to one and its no way near that noisy in real life.

[Subculture]

Blimey that's a noisy little critter. Here's the little planetary geared motors I referred to inan earlier posting- http://www.ebay.co.uk/itm/Mini-Elect...item2ec162b1c1

Little works of art those are, work fine off 5 volts. I purchased a couple to experiment with servo electronics and baby piston trim tanks. But that's another story....

[RCnut]

Well tell me what you wanna see and I'll tape it. lol

[He Who Shall Not Be Named]

What a tease! The video hangs-up at 1:22 Damn!!!!!

David

[RCnut]

As promised the latest Ratemaster test.

http://www.youtube.com/watch?v=wJwMsoPYawU&feature=youtu.be