Stingray Build

[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]

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?

[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:

[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]

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]

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

[Captain Scifi]

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

I laughed so much at the above coffee came out of my nose and I couldn't work for 20 minutes.... LOL

Won't it be easier to do as Mamas did and lay out all the control linkages, install the hull SD tube clamps and various whatnot's before closing the hull halves? I am as dextrous as the next chap but why struggle with a restricted entry space?

The Clear laser cut parts are fine in David's kit the holes positions for the bearings may need a tweak but he is the world's experts at such things. I have worked up a design for an adjustable bearing backplate but I now find myself on jury duty from Monday for at least two weeks. I'll cut and send a test set of parts as soon as I get back. Lastly, and rather embarrassingly I have just found a pair of Aquasprite canopies that I made and forgot to drop into the kit, sorry David, I will put them in the post to you at my first opportunity.

I feel really good about this kit, optimistic to start building it, thrilled by the quality of the work Mamas put in to produce it and delighted David has agreed to sort out the electrickery things I don't fully understand. It has been suggested that one could swop tops and replace the cabin section completely when RC driving this model, one with slightly frosted windows and block details and one "Sunday best" with all the fixings. It's a good idea and I'll go with that.

Brass wire is on order and I can hardly wait....

[Subculture]

Just a note about dog bone couplings, I think Mamas will back me up here- they're not easy to source in the UK. Popular in the States because Dumas sell them.
Here people tend to use the raboesch/Huco type couplings, a single cardan style joint. Not the most ideal coupling, but they do the job.
Not sure the nylon/brass Dumas dog bone woud be up to brushless power though!

[RCnut]

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

David

I just got in (Went to see my Kids) I have removed everything but I'll get it all back in there in the morning and give you all the info ASAP.

[He Who Shall Not Be Named]

Not wishing to hijack Mamas' thread I'll only post my assembly of his beautiful STINGRAY kit with the barest of narrative. I'm doing it here to compliment his good work, not to suck all the oxygen out of the room.

For a more comprehensive look at my work look to future postings of The Cabal Report and The Sub-driver Gazette.

So far I've done a mock-up of the 2.5" Sub-driver specifically designed to operate this critter. Once I have mine up and working, I'll make up like units for Mamas and his associate -- the guys who made this kit possible and were kind enough to send me this sampe of their work.

Barter, boy's and girls ... don't leave home without it!

The relatively small diameter cylinder leaves room for an almost complete cockpit interior set into the upper hull ... maybe even room for the 'well' where the checkers-board is?

Here's a great youtube video that shows ALL the cockpit and well interior, http://www.youtube.com/watch?v=HrRKp...eature=related Wish I had this kind of resource when I did the XL-5 Junior and 'secondary conn' cockpit back in the early 80's! Computers can present more than porn, who would have thunk it?!

I found three old Astro-Craft planetary 'stacked' motors. Each will be ideal as prim-mover for the heavy RateMaster.

The saga continues!



David

[alad61]

This is like watching a series of 24 at about episode 18 only better!!

[He Who Shall Not Be Named]

Did you see Alec's post, Mamas? High praise indeed!

David

[Subculture]

That's a nifty little trick with the washer and sharpie to get the ledge on the cockpit recess. I tend to use a stick, to get the offset, but that looks a lot easier.

[RCnut]

I'm Very happy and thankful with the high praise from all And In return I can only say that the work David Is doing now Is knocking me for Six, Cant wait to get my hands on that SD unit.

Mamas

[He Who Shall Not Be Named]

That's a nifty little trick with the washer and sharpie to get the ledge on the cockpit recess. I tend to use a stick, to get the offset, but that looks a lot easier.

I used to hang-out at the free-lance Pattern and Foundry shops around Detroit. Picked up little things like that by watching old guys working up wooden patterns for the green-sand packers.

David