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Author Topic: New Electric Twin project back on track  (Read 113804 times)

Online Bob Hunt

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Re: New Electric Twin project back on track
« Reply #100 on: February 09, 2011, 11:38:28 AM »
Hi Larry:

Yes, there is! But... one thing at a time - or in this case, two things at a time. There's plenty of time to add more later in another design... Obviously there will soon be a very sleek and stylish nose cone added to this ship.

To answer your question, Bill Little, I use very thin butyrate dope to attach the .2 carbon mat.

Bob


Offline Bill Little

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Re: New Electric Twin project back on track
« Reply #101 on: February 09, 2011, 11:46:17 AM »
Thanks, Bob.

Bill
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Offline Dean Pappas

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Re: New Electric Twin project back on track
« Reply #102 on: February 10, 2011, 11:18:43 AM »
Hi Bill,
Isn't there always a STORY ?

Dean
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Offline Andrew Borgogna

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Re: New Electric Twin project back on track
« Reply #103 on: February 10, 2011, 01:59:48 PM »
Hey Bob, I know where Larry is going he wants to build a 1/2a version of your plane. 
Andy
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Offline Howard Rush

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Re: New Electric Twin project back on track
« Reply #104 on: February 10, 2011, 03:52:31 PM »
Obviously there will soon be a very sleek and stylish nose cone added to this ship.

I have been trying to come up with a suitable nose joke to no avail, but this reminds me of a story.  One time in 1968 I was in a Shakey's in St. Louis.  I saw a woman who looked very familiar.  Specifically, the profile of her nose looked very familiar.  I later realized that it was identical to the wing planform of the Concorde.
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Offline Bill Little

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Re: New Electric Twin project back on track
« Reply #105 on: February 10, 2011, 04:01:51 PM »
Hi Bill,
Isn't there always a STORY ?

Dean

Generally speaking.... yes.

"Mongo"
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Online Bob Hunt

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Re: New Electric Twin project back on track
« Reply #106 on: February 11, 2011, 08:43:05 PM »
It's Nacelle time!

Now that the CG point has been found and the nacelle length has been determined for real, it's time to make the actual nacelles for this monster. I'm attaching a photo of the drawing of the finalized nacelle shape. Note the placement of the retracted main wheel; it's just in front of the leading edge.

The second photo is of the nacelle parts. There are four nacelle sides and four 1/32-inch ply doublers. I put as many holes in the doublers as I thought prudent. These parts weigh 1.5 ounces without the epoxy that will join them. The target weight of the bird was at first 63 ounces, but I guess I budgeted high because now its looking more like 58 or 59 ounces all up. I'll be very pleased with that!

As soon as I post this message I'll attach the doublers to the nacelle sides. Tomorrow I'll trim the doublers to match the nacelle sides and install the formers and make them up into two assembled nacelles. Hopefully by the end of next week I'll have all the woodwork done and be into finish. This has been fun!

Bob Hunt   

Offline Mike Scholtes

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Re: New Electric Twin project back on track
« Reply #107 on: February 11, 2011, 09:33:06 PM »
This may be putting the cart a tad before the horse, but are you considering kitting this spectacular beastie, maybe as a component group? Of course you will need to prove it flies well enough to satisfy your design goals but I think that is a safe assumption.

Offline Keith Renecle

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Re: New Electric Twin project back on track
« Reply #108 on: February 11, 2011, 09:56:36 PM »
Hi Bob,

This is one awesome design! I love the shape of these nacelles. In fact, the whole design is so stylish. When I looked at the drawing, for a minute the nose cone on the fuselage looked like a spinner. Maybe the upgrade will be a tri-motor?? I can't wait to see this one completed. Keep going!

Keith R
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Offline PJ Rowland

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Re: New Electric Twin project back on track
« Reply #109 on: February 11, 2011, 11:02:35 PM »
Looking great.
If you always put limit on everything you do, physical or anything else. It will spread into your work and into your life. There are no limits. There are only plateaus, and you must not stay there, you must go beyond them.” - Bruce Lee.

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Online Bob Hunt

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Re: New Electric Twin project back on track
« Reply #110 on: February 12, 2011, 07:19:30 AM »
Hi Mike:

You're right; that is putting the cart way before the horse! But, thanks for the suggestion. If (and it's a big if right now...) this thing flies as well as I hope it will I will probably make plans and some of the components (Lost-Foam wing fixtures and molded shells) available. I really don't think that the stunt world in going to beat a path to my door over this one. It is a bit labor intensive; but not nearly as much as I originally thought it would be. It presented some interesting engineering problems, but so far all of them have been fairly easy to solve. Striking out  into unfamiliar territory can make a person tread slowly and carefully and expect the worse. Again, in this case (so far...) things have gone incredibly well. I'm waiting for the other shoe to drop...

Keith:

Thanks for the kind words on the styling! Anyone who knows me well knows that the styling part is why I really do this stunt thing to begin with. I just love sketching and drawing swoopy looking stuff and then translating those lines into balsa. A tri-motor? What ever made you think that there might ever be a tri-motor version of this?  VD~

PJ:

Thanks! Looking forward to seeing you at the Nats. That beer you were suggesting sounds interesting, but we can at least get together with a group and do some dinner. I might be persuaded to imbibe one beer's worth. I suppose it would have to be a Fosters...

I just took the weight off of the nacelles side/doubler sandwich and now all the parts weigh 1.6 ounces. I was budgeting 2.5 ounces per nacelle finished and I think I have a good shot at being at or below that number. I'll do a lot on it today.

Later - Bob 

Offline Ward Van Duzer

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Re: New Electric Twin project back on track
« Reply #111 on: February 12, 2011, 08:52:26 AM »
You're BOTH Mongos, ceptin' Dean-O is a little closer to the ground!

Ward-O
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Offline William DeMauro

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Re: New Electric Twin project back on track
« Reply #112 on: February 12, 2011, 09:28:51 AM »
I see you made some good progress on it this week. I can't wait to see it with the Nacelles on it they really bring the style out.As you know I'm looking forward to seeing it finished. Sometime this summer I will hit you up for a flight on it.
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Online Bob Hunt

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Re: New Electric Twin project back on track
« Reply #113 on: February 12, 2011, 09:46:22 AM »
Hi Will:

No problem, but that flight will have to be after the Nats... ;)

Online Bob Hunt

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Re: New Electric Twin project back on track
« Reply #114 on: February 12, 2011, 12:09:20 PM »
Here's an update on today's work on the twin.

The nacelles are well underway. They have the doublers attached and have been joined with two formers each. The actual shapes of the nacelle sides were determined by cutting inner and outer core sections of the twin's wing and then covering them with the same thickness sheeting that was used on the actual wing. In this case that would be 1/16-inch thick balsa. The position of each of the nacelle sides was then scribed onto the "dummy" covered foam pieces and then they were band sawn chordwise to yield the exact shape of the wing where the nacelle sides will reside. They fit perfectly! Of course the nacelles will be final attached using a special fixture that will insure perfect alignment all around.

Here are a few photos from this morning's work. Later this evening I will make the motor mount plates and install them, mount the motors so that I can position the nose rings, and cut and fit the blocks that will be carved to achieve the final shapes of the nacelles.

Later - Bob
 

Offline Bill Little

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Re: New Electric Twin project back on track
« Reply #115 on: February 12, 2011, 03:25:25 PM »
Ah ha!  The "Lost Foam technique" strikes again!  (sounds like how you made the nacelles/wing fitting) ;D

Bill
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Offline Dean Pappas

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Re: New Electric Twin project back on track
« Reply #116 on: February 13, 2011, 11:51:47 AM »
You're BOTH Mongos, ceptin' Dean-O is a little closer to the ground!

Ward-O
A low CG is good ... better handling, you see.

On a note more tied to the discussion: I just love how the fixturing falls out of the construction process.
Way to go, Bobba!
  Dean
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Offline PJ Rowland

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Re: New Electric Twin project back on track
« Reply #117 on: February 13, 2011, 04:05:50 PM »
Quality of those Nacelles looks top draw. - Certianly one of the Highlights for me will be seeing this Machine doing its thing. It will certainly be impressive.

Bob:  y1 Certainly will have to organise something - Im not real beer drinker - More of a light Bourbon man myself. I would enjoy us all going out in decent sized group - table full of who's who ! I'd love to hear you say " I won a world champs before you were born love - now bring me a steak. "  LL~

I'l talk to you at the Nats and we can organize somethign there ( Where are you staying? I'm at the Comfort Inn ) - Robbie mentioned visiting - Id like to see your shop so I'l make a special trip when im near DC out to your place - but your twin build thread isnt the place to be doing it ! Enjoy the build I look forward to seeing the completed ship - and catching up again at the Nats - Keep us all posted on the goings on.

Does it have a Name yet? Did I miss that?
If you always put limit on everything you do, physical or anything else. It will spread into your work and into your life. There are no limits. There are only plateaus, and you must not stay there, you must go beyond them.” - Bruce Lee.

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Online Bob Hunt

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Re: New Electric Twin project back on track
« Reply #118 on: February 13, 2011, 06:20:32 PM »
Hi PJ:

Yup, we'll find a way to get a group together and do some dinner for sure. Hopefully Robby will make it out to the Nats for at least one day.

Okay, got a lot done today. I designed the motor mount plates and made them from very high grade, 5-ply birch plywood and then coated them on both sides with .2 carbon mat applied with thin CA glue. I had to make up a special fixture that would allow the nacelle sides to sit parallel to the table and have integral vertical pieces that would insure that the motor mount plates were being installed perpendicular to the actual nacelle centerlines.

Once the plates were accurately glued to the nacelle sides I carefully marked and drilled through the nacelle sides and into the plywood mount plates in three places on each side of the nacelle assembles. I used round toothpicks with a bit of the tapered end snipped off as press-fit dowels and installed them with medium CA glue. Once the CA had set I snipped the ends of the toothpicks with a pair of diagonal cutters and then sanded the "pins" flush with the nacelle sides.

The units weigh 1.3 ounces total - that's both units! Unfortunately I cannot go much further until I get the 1/1/2 inch diameter spinners. I have to mount the motors, install the noserings and then fit the top and bottom balsa blocks for carving. I opted to use blocks in this case instead of molded shells because I can actually do the blocks quicker and I want to get this monster into finish as soon as possible.

That's it until later this week.

Thanks - Bob Hunt      
« Last Edit: February 13, 2011, 10:13:22 PM by Bob Hunt »

Offline PJ Rowland

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Re: New Electric Twin project back on track
« Reply #119 on: February 13, 2011, 06:40:00 PM »
Its amazing how strong .02 Veil is once you hit it with Zap - Often I will coat the inner half of a Moulded Shell with Carbon Veil to keep it from loosing shape in lieu of using bulkheads.

Just need to watch out when it flashes off - can mess up your eyes like oinions !


Love the detail in the photos' I dont know how many people realise some of these photo's are taken specifically for our viewing purpose they are not simply workshop shap shots. Carefully set up, well pictured and uploaded - all that takes time - We all appreciate your efforts. - Photos make the forum alot of fun.

Keep up the great work. Its defenetly ATD compliant. ( Attention to detail. )
If you always put limit on everything you do, physical or anything else. It will spread into your work and into your life. There are no limits. There are only plateaus, and you must not stay there, you must go beyond them.” - Bruce Lee.

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Offline Keith Renecle

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Re: New Electric Twin project back on track
« Reply #120 on: February 16, 2011, 06:07:14 AM »
Hi Bob, You asked:

Keith:

Thanks for the kind words on the styling! Anyone who knows me well knows that the styling part is why I really do this stunt thing to begin with. I just love sketching and drawing swoopy looking stuff and then translating those lines into balsa. A tri-motor? What ever made you think that there might ever be a tri-motor version of this? 

Any Questions??

Keith R

Keith R

Offline Bill Little

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Re: New Electric Twin project back on track
« Reply #121 on: February 16, 2011, 06:24:01 AM »
A tri motor set up on electric would be just too cool.  I don't believe the wind would have much to say with the usable power that would be present.  And with the systems becoming "smarter" everyday, it appears, it would take more than a mild hurricane to ground the model! ;D

Great looking work, Brother!

"Mongo"
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Offline Mark Scarborough

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Re: New Electric Twin project back on track
« Reply #122 on: February 16, 2011, 09:21:00 AM »
and with three props,, you could use smaller diameter props and still have MORE prop disk area,,
hmm that means an even lower slung undercarriage,, wo hoo, can you say low rider
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Offline Larry Renger

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Re: New Electric Twin project back on track
« Reply #123 on: February 16, 2011, 10:18:28 AM »
I seem to have unleashed a Frankenfurter!   VD~
Think S.M.A.L.L. y'all and, it's all good, CL, FF and RC!

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Offline PerttiMe

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Re: New Electric Twin project back on track
« Reply #124 on: February 16, 2011, 10:39:52 AM »
Perhaps this is blasphemy but I was reminded of an Electric Twin R/C project I followed on rcgroups:
http://www.rcgroups.com/forums/showthread.php?t=1075719&page=23

I built a Blue Pants as a kid. Wish I still had it. Might even learn to fly it.

Online Bob Hunt

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Re: New Electric Twin project back on track
« Reply #125 on: February 16, 2011, 11:31:24 AM »
Isn't that a great looking RC twin? It's Mark Rettingers and I cut the wings for it! Yes, Mark and I spoke quite a bit about the similarities between our designs. They were both designed without either designer knowing of the work of the other. Mark is now selling plans for that ship and I have been chosen as the core supplier. Mark has several other very nice electric RC designs, including a nifty P-51. Yup, I cut the cores for that one too!  ;)

By the way, I've come up with a new name for my twin design. I'm going to call it (drum roll here please) "Second Wind."

Later - Bob Hunt

Offline PJ Rowland

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Re: New Electric Twin project back on track
« Reply #126 on: February 16, 2011, 03:05:29 PM »
Second wind is a phenomenon in distance running, such as marathons or road running (as well as other sports), whereby an athlete who is too out of breath and tired to continue suddenly finds the strength to press on at top performance with less exertion. Some scientists believe the second wind to be a result of the body finding the proper balance of oxygen to counteract the buildup of lactic acid in the muscles. Others claim second winds are due to endorphin production, while still others believe it to be purely psychological.


Sounds like a great name to me.

3 x Prop version? I think you do a twin then progess to 4.. No baby steps.
If you always put limit on everything you do, physical or anything else. It will spread into your work and into your life. There are no limits. There are only plateaus, and you must not stay there, you must go beyond them.” - Bruce Lee.

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Offline Dean Pappas

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Re: New Electric Twin project back on track
« Reply #127 on: February 16, 2011, 03:33:06 PM »
Wait a cotton-pickin' minute here!
I thought the whole point of the twin was to eliminate the trim problems caused by spiral airflow and GP with couterrotating props.
A trimotor ... SIGH n~

later,
  Dean P.

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Online Bob Hunt

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Re: New Electric Twin project back on track
« Reply #128 on: February 16, 2011, 05:14:19 PM »
Yeah, all that PJ said, and the fact that the twin has two motors and makes twice the amount of "wind." Twin motor; second wind... These things are never good when you have to explain them.

I thought when I first started designing it that it looked a bit like the COIN fighters from the Vietnam era and so floated the name COIN Return around. Man, nobody got that one!

Later - Bob Hunt 

Offline PJ Rowland

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Re: New Electric Twin project back on track
« Reply #129 on: February 20, 2011, 04:44:29 PM »
Like this you mean??



Would have been a very essoteric name - Second wind is cool.

If you always put limit on everything you do, physical or anything else. It will spread into your work and into your life. There are no limits. There are only plateaus, and you must not stay there, you must go beyond them.” - Bruce Lee.

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Online Bob Hunt

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Re: New Electric Twin project back on track
« Reply #130 on: February 21, 2011, 07:17:38 AM »
Hi PJ:

Yup, that's one of them. I had in mind the OV-10A Bronco when I thought of COIN fighters. I used to watch them fly around everyday when I was in the Army back in 1968. Very neat ships and the future will most certainly see an OV-10A derivative design for electric.

I got the spinners from Tru-Turn and they are beautiful! Very light and one of them has prop cutouts for a pusher prop and the other is cut for a standard rotation prop. I mounted the motors in the nacelles last night but did not get the nose rings cut and mounted. Hopefully I'll get to that tonight and then I'll post some photos of the blocks being fit to the nacelles for carving.

Later - Bob 

Offline John Miller

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Re: New Electric Twin project back on track
« Reply #131 on: February 21, 2011, 09:45:51 AM »
Hey Bob, this project just seems to get better and better. I really like what you're doing. I'm soo looking forward to the flight reports on this one. I hope to be able to see it perform. Have you considered a trip to the NW Regionals? HIHI%%

I also plan on gleaning as much info, from you, on electric twins, for my next Twin PF.

Getting a line on life. AMA 1601

Online Bob Hunt

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Re: New Electric Twin project back on track
« Reply #132 on: February 21, 2011, 11:30:29 AM »
Hi John:

Thanks for the comments. I don't know how much I'll be able to help with twin technology. We could both learn a bunch from Gordan Delaney however... y1 I sure loved the way his Profile Pathfinder Twin flew!

Here's a shot or two of the nacelles with the motors mounted and the spinners on. I have not yet made the nose rings. Hopefully I'll get to that tonight.

Later - Bob

Offline John Miller

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Re: New Electric Twin project back on track
« Reply #133 on: February 21, 2011, 01:16:03 PM »
Sharp Bob, It's looking good.

It's my good fortune that I live just down the road from both Gordan and Norm. What I hope to learn from you are settings, more towards the motors, and batteries, some esoteric  things like which is the best way to set up the counter-rotation, lefty-righty, or righty, lefty.

So far, all the twins I've flown have the props both rotating CCW. So my interest is high on the outcome, knowing how those previous twins have performed with them both going the same way. I'm hoping that my long held assumption that at our sizes, counter rotation is of little benifit, is false #^.
Getting a line on life. AMA 1601

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Re: New Electric Twin project back on track
« Reply #134 on: February 21, 2011, 01:43:05 PM »
Wait a cotton-pickin' minute here!
I thought the whole point of the twin was to eliminate the trim problems caused by spiral airflow and GP with couterrotating props.
A trimotor ... SIGH n~

later,
  Dean P.


The center motor just needs a C-rot prop. Simple?? Yes I am.....

Offline Howard Rush

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Re: New Electric Twin project back on track
« Reply #135 on: February 21, 2011, 01:45:46 PM »
I sure loved the way his Profile Pathfinder Twin flew!

Me too!
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Offline Tim Stagg

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Re: New Electric Twin project back on track
« Reply #136 on: February 21, 2011, 03:06:45 PM »
e-flite 10's huh Bob....I thought I was the only e-flite motor user out there, let me know how they work out for ya

Tim
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Online Bob Hunt

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Re: New Electric Twin project back on track
« Reply #137 on: February 21, 2011, 04:58:11 PM »
Hi Tim:

Yup! That's what Deano said to use and that's what I'm doing. I wanted to use the Park 480 motors but the shaft size is so small in diameter (3mm) that we thought they might bend under the maneuvering loads of CL Stunt. Perhaps we can convince Pete Bergstrom to have a word with the fine folks at Horizon and get a version of the Park 480 with a 5mm shaft... Pete, you out there? Pete? Pete?

Actually E-Flite and Horizon have been extremely accommodating to us recently. Pete asked me about spinners recently. He wanted to know what sizes and styles that I thought the CL community might like. Not too long after that I received a few very nice spinners that had the collet mount assembly neatly built into the backplate of them. Outstanding quality! I'm quite certain that we will have a new product announcement about these spinners very soon. I know that I'm using the 1 3/4 - inch diameter spinner that he sent on my new Crossfire!

I have also tried the E-Flite Power 25 as an alternative to the AXI 2826-10 and it works extremely well. Again, the new Crossfire will have one of these Power 25 motors in the nose.

Later - Bob

Offline Larry Renger

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Re: New Electric Twin project back on track
« Reply #138 on: February 22, 2011, 09:23:13 AM »
gorillabobsrc.com has counter-rotating motor systems in a couple of sizes....  VD~
Think S.M.A.L.L. y'all and, it's all good, CL, FF and RC!

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Offline Jim Pollock

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Re: New Electric Twin project back on track
« Reply #139 on: February 24, 2011, 10:40:39 AM »
And,

I'm supposing Bob's motors will be counter-rotating as well - right Bob???

Jim Pollock   ;D

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Re: New Electric Twin project back on track
« Reply #140 on: February 24, 2011, 11:43:28 AM »
Hi Jim:

Yup! I'll have them setup to turn opposite to each other in either of the two directions. I can test all four possible combinations (both turning to the left, both turning to the right, outboard turning left and inboard turning right and outboard turning right and inboard turning left) at the field and make comparisons. Should be fun!

Later - Bob

Offline Howard Rush

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Re: New Electric Twin project back on track
« Reply #141 on: February 24, 2011, 12:46:00 PM »
It will be even more fun when you get the props mixed up and take off. 
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Online Darkstar1

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Re: New Electric Twin project back on track
« Reply #142 on: February 24, 2011, 12:48:48 PM »
Bob
Does E-flite plan to have spinner cutouts for pusher props for sizes up to 2.5 in.
Later,
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Online Bob Hunt

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Re: New Electric Twin project back on track
« Reply #143 on: February 24, 2011, 01:27:56 PM »
Hi Darrell:

I'm not sure just how many sizes and shapes they will offer. I know that they have a 1 3/4-inch conical and a 2-inch bullet with the reverse pitch openings because Pete sent me one of each of those for evaluation and use. Again, they are absolutely beautiful and have the collet mount built right into the backplate. I assume that they will also have normal backplates for those who are using rear-mount motors.

I'll ask Pete what other sizes and shapes they intend to make the next time I speak with him.

Thanks for taking care of Tom Hampshire while he was down there; he said he had a great time with you and Frank Williams.

Later - Bob

Offline Larry Renger

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Re: New Electric Twin project back on track
« Reply #144 on: February 25, 2011, 07:55:30 AM »
How about contra-rotating motor systems for both nacelles.  No need to experiment then!   >:D  S?P  VD~  LL~
Think S.M.A.L.L. y'all and, it's all good, CL, FF and RC!

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Online Bob Hunt

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Re: New Electric Twin project back on track
« Reply #145 on: February 25, 2011, 10:26:35 AM »
One thing at a time, Larry... Trust me, we've thought of your suggestion and a lot more configurations as well quite a while back. Electric flight allows us to innovate in design at a whim, but the best results should be attained by taking the next logical step and finding any of the potential pitfalls as we go. We can then design the next "outrageous" thing with a lot of confidence that it will be sucessful on the first try. Baby steps... (Just like in the movie "What about Bob").

Later - Bob 

Offline Keith Renecle

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Re: New Electric Twin project back on track
« Reply #146 on: March 04, 2011, 01:12:43 AM »
Hi Bob, I need to come back to my question that I asked earlier about how do you work out how much power to use on twins or multiple engined stunters. I seem to remember that Dean also said he would give it some thought. Your choice of E-Flite Power 10 motors seems like a good idea. When I checked the specs out on their website, they rate them as .10 glow engines. In C/L terms there is no way that these motors could be rated this way. They weigh 120 grams or so, and the size windings etc. indicate that they would at least be equivalent to a .25 to .30 glow engine.

PW's bomber used 4 x FP.15's but there is no way that multiplying this out to be a single .60 would fly a 2.8 kg. bomber. So, once again, it would be nice to know how you work this out. Maybe Howard has this figured??

Just by the way, what size props did you finally decide to use? Thanks.

Keith R
Keith R

Offline PJ Rowland

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Re: New Electric Twin project back on track
« Reply #147 on: March 06, 2011, 02:27:25 AM »
I dont know exactly what the formular is either..


Spitfire was : 6417 Lbs

Lancaster :  Empty 36,900 lbs, Maximum Takeoff 68,000

Both aircraft used the Merlin engine..

6417 X 5.6 = 36000

I just weighed a little model built for an OS 19 called an Aerobat. Typical 22 "  That weighs 20.5 OZ.
Doing the same maths
20.5 x 5.6 = 114 oz

So in theory that is the same power to weigh to lifting ratio..  - I don't have the required aerodynamic knowledge to explain why - once you go to 4 engines you can carry more weight that you think - and Yes your correct ..

4 x 15 = 60 and there is no way a 60 would pull around a 110oz aircraft.

The Lancaster proved the similar concept - running 4 x 19 = 76 and mine was heavier at 118 - 120 oz Interesting enough - Like PW - I found you can still do maneouvers on 3 engines - 8's squares ect..

The model will also fly on 1 engine - well - staying airborne is flying ..


Perhaps some of the more learned folk out there can expain the answer - Both bombers proved what the full sized counterparts found, that you can carry more weight. - I've read reports that the Lancaster was quite nimble in the air - I found the same - quite surprising..


I've never dabbled in twins - so I am also keen to read the expected answer into how do you select the engine size - and is it a similar ratio for twins as it is for 4's??

Does the math's halve when you run a twin..

Instead of 5.6 times - its reduced to 2.8 ?

Loaded weight: 17,700 lb Mosquito
6417  Spitfire

6417 x 2.8 = 17 967

Interesting............  y1

Going on that theory, im sure you can calculate what you would require.






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Offline Keith Renecle

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Re: New Electric Twin project back on track
« Reply #148 on: March 06, 2011, 05:53:24 AM »
Interesting data........thanks PJ.
Keith R

Offline Mark Scarborough

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Re: New Electric Twin project back on track
« Reply #149 on: March 07, 2011, 10:00:21 AM »
I am NOT Bob, but I have thought about twins, ( and more) Were I to want to calculate this, My technique would be simply to look at the watts available for power. Pretty easy with electrics
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