Flying High With Electric Power! The Ampeer ON-LINE! June 2011 The Club Newsletter of the Electric Flyers Only, Inc AMA Charter 2354 Commerce Twp., MI, USA Editor: Ken Myers Fly the Future - Fly Electric!

President:	Vice-President:	Secretary/Treasurer:
Ken Myers	Richard Utkan	Rick Sawicki
1911 Bradshaw Ct.	240 Cabinet	5089 Ledgewood Ct. W.
Commerce Twp., MI 48390	Milford, MI 48381	Commerce Twp., MI 48382
(248) 669-8124	(248) 685-1705	248.685.7056
Board of Directors:	Board of Directors:	Ampeer Editor
David Stacer	Arthur Deane	Ken Myers
16575 Brookland Blvd.	21690 Bedford Dr.	1911 Bradshaw Ct.
Northville, MI 48167	Northville, MI 48167	Commerce Twp., MI 48390
248.924.2324	248.348.2058	248.669.8124
Mailed Ampeer printed subscriptions are no longer available. The Ampeer is FREE on-line in Acrobat .pdf format and HTML with active links!
The Next EFO Meeting: Date: May 18 Time: 10 a.m. Place: Midwest RC Society 7 Mile Rd. Flying Field

What's In This Issue?
Oh Dear, DEWALT Changing Lithium Batteries!	The Event Formerly Known as E-Fli-owa	Don Belfort's Nesmith Cougar Update	Willie McMath's Loving's Love
Two 'Big Brand Name' Companies Are Now Suppliers of Outrunner Motors	The April EFO Meeting	RCCD WOW Meet Postponed	RBC Kits
Shoulder-wing Toledo Special	A Foam Antonov An-2	Put This One On Your Event Schedule!	The 2011 Mid-America Electric Flies Information
Upcoming E-vents		Send Ken email

EFO Flying Meeting, Saturday, June 18      The flying meeting is scheduled for Saturday, June 18. See ya then. Oh Dear, DEWALT Changing Lithium Batteries! From John Bell via email Hello Ken:      My name is John Bell and I come from Ontario and occasionally visit the Mid Am. Met you at Toledo this year (with Keith) and briefly discussed 123 cells.      I have recently bought 2 DEWALT 36V Packs on Ebay. I am familiar with the DEWALT pack, having bought several over the years, but this time I got a surprise.      The first pack I opened was as expected, 10x2300mAh cells in Series, but the second pack was the surprise---20 smaller cells in Series/Parallel!!!!      I was caught completely off guard as I didn't know that DEWALT used smaller cells in their 36V Power packs--I assume the cells are 1100 mAh capacity, but I don't know.      Are you aware of this and if so, do you have any additional information on them?      The outside of both packs is identical and both would fit into a DEWALT Charger. That means that they would need to be charged in Series/ Parallel pack to use the same charging rate as I now do??? Any help would be appreciated, Thanks, John Bell Hi John,      I just read about this on RC Groups this past week (early May). Very disturbing! At least to me.      I know nothing about the smaller Samsung cells.      Here is the thread about this on RC Groups.      There appears to be a weight difference noted in the thread, so you can tell before opening the pack. Later, Ken More Info from the RC Groups Thread      It appears that the DEWALT packs with "A123" 2300mAh cells in them are made in China and the ones with the Samsung cells are made in Taiwan.      The following was posted by Andy Telzer in the noted RC Groups thread:      "I have another DeWalt 36V battery. From the outside they are identical, both say DC9360. The green cell pack has a production date of 2010, while the other one with the regular 123 cells has a date of 2009.      The green cell pack on the back of the case says the cells were made in Korea and assembled in Taiwan. The regular 123 cell pack says made in China. The green cell pack weighs 2lb 11.7oz. (43.7 oz.) The regular 123 cell pack weighs 2lb 8.1 oz. (40.1 oz.)      One very subtle difference that you can see, but just barely, is where the DeWalt pack plugs into the charger. If you look closely the black plastic molding that holds the charging pins on the green cell pack it has a part number of MX 4B. That number is molded into the plastic in the female part of the receptacle. The numbers are very tiny maybe 1mm in height.      Now if you look at the same molding on the regular 123 pack the part number is MX 2A. Maybe someone can confirm this part number on their pack.      Perhaps all the newer DeWalt packs have the green cells, or maybe just the one from Korea/Taiwan? Worth a call to DeWalt for a few answers? Cheers Andy" Photo of the Samsung Cells Return to "What's In This Issue" The Event Formerly Known as E-Fli-owa Update from Plenny Bates via email Ken,      I told Darryl that I would send this along to you with more information than before.      Thanks for publishing.      Try some of the links. The site is nice. Plenny Bates The Event Formerly Known as E-Fli-owa Saturday-Sunday, September 10-11, 2011 Rockwood Field, located in Rockwood State Park, Morrison, IL Open flying for all Electric R/C Aircraft on beautiful 450' x 100' grass runway. Landing fee, $15 both Days, $10 for single day. (Includes lunch for Pilots) Door Prizes! Raffle!! Food available Registration: 8:00 AM, Flying: 9:00 AM, (Both Days) AMA Sanctioned Event # 11-1431 AMA Membership Required Camping, Hiking, and Fishing available in the park (reservations suggested for campers: See www.stateparks.com/morrisonrockwood.html) Lodging available in nearby Fulton, Rock Falls, and Sterling, IL See www.mmafrc.org for field location and more info, or contact CD: Darryl Miller, 815-625-4161 dlmrcpilot@gmail.com Hosted By the Morrison Model Aircraft Flyers Radio Control Aircraft Club!! Return to "What's In This Issue" Don Belfort's Nesmith Cougar Update From Don Belfort via email Hi Ken,      I still have some work to do but the Nesmith Cougar has had a successful test flight! I can't make Keith's Birthday fly-in due to my son's wedding but I will do my best to have it at Mid-Am! See you soon, Don      Congratulations on the successful maiden of that beautiful plane. Hope to see you and it soon. KM Return to "What's In This Issue" Willie McMath's Loving's Love From Willie McMath and others via email      Various emails have been combined to provide the following information. KM      Here are the details on my Loving's Love. The design was scaled up from three-views in the September 1958 Model Airplane News.      At one-third scale it has a wingspan of 81 in. and a length with the big spinner of 68 in. It weighs approximately 16 lb.      The power system consists of a Turnigy 50-65-350 Kv outrunner, a 100-amp Turnigy ESC and a 9S2P "A123" 2300mAh pack providing 4600mAh because of the paralleling. The prop is a 19x10. I have no power readings yet as at this time I still have to hook up ailerons and balance it. I will let you know when I get readings. Willie McMath Hello Ken,      About 80% of the magnets moved after the first run and shut right down.      This is Turnigy 50-65-350kv. I ordered a Turnigy-SK series 50-65-270kv.      I hope this one will work OK. I will have all summer to get the magnets back in place. Willie McMath and Hello Guys,      I need both of your opinions. As soon as I fired up the motor, the magnets locked up. What is your opinion on glue to re-glue the magnets? Willie McMath HI Willie,      If I remember, you're using one of the big Turnigy motors. These have been known to loose a magnet. You will have to disassembly the motor end bell so you can get at them. Once you make sure the magnets are in place (don't change the direction of any magnets), the best glue is thin CA. Epoxies get soft at high temperatures, but CA gets stronger at high temps. Jim Young T&J Models Video of Willie's maiden flight.      Congratulations on your successful maiden and beautiful model! Great Job Willie! KM Return to "What's In This Issue" Two 'Big Brand Name' Companies Are Now Suppliers of Outrunner Motors By Ken Myers      O.S., famous for their 2-stroke and 4-stroke glow engines and Futaba, famous for their radio systems, are now supplying outrunner motors to the RC market. O.S. Motor has four outrunner motors.      The specifications for these outrunners. English info      The O.S. nomenclature is followed by the can diameter can length dash Kv and weight in parenthesis. OMA-3820-1200 (3843-1200, 155g) OMA-3825-750 (3848-750, 190g) OMA-5020-490 (5053-490, 350g) OMA-5025-375 (5058-375, 405g)      Tower Hobbies is marketing them in the USA and gives an expected delivery date of late July 2011.      According to Tower Hobbies the, "Centrifugal fan design with angled ventilation holes draws air through the motor and across the windings and magnets for improved cooling."      Tower Hobbies has "renamed" the motors to what they believe to be equivalent glow size motors.     Futaba has three motors. The Futaba nomenclature is; FMA-5065KV300 FMA-5055KV410 FMA-5055KV525     The specifications are not available, but it looks like they are using the diameter and length of the can followed by the Kv.     I expect Tower Hobbies to also carry the Futaba motors, as they are the supplier of Futaba radio systems.     More details will be provided when they become available. Return to "What's In This Issue" The April EFO Meeting By Ken Myers      The April EFO meeting was held at Ken's house on April 13. It was well attended.      The following topics were discussed, but not necessarily in the following order. Props stuff: APC prop list.      For some reason, the APC pages take quite a long time to load, be patient. APC RPM limit formulas. Glow engine and Speed 400 Electric props: Maximum RPM=190,000/prop diameter (inches) Thin Electrics and Folding Electric Props: Maximum RPM=145,000/prop diameter (inches) Slow Flyer props (discussed at the meeting) Maximum RPM=65,000/prop diameter (inches) GWS Props at BP Hobbies      BP Hobbies is a good resource with all GWS (Grand Wing Servo) props listed. RS - Reduction Series (similar use as APC SF - BP calls them slow flyer) DD - Direct Drive (HD & DD have similar applications to APC E Thin Electric props) HD - Hyper Drive 3-Bladed 4-Bladed      There is a nomenclature problem with the GWS props. It is difficult to tell from the GWS part number what type of prop it is.      An EP-1180 is an 11x8 RS (slow flyer) type prop, while the EP-1170 is an 11x7 DD (direct drive) prop.      Ken discussed and demonstrated an Excel workbook that contains spreadsheets for glow to electric conversions using outrunner motors and either Li-Poly batteries or "A123" 2300mAh cells. The Excel workbook for glow to electric conversions.     A stall speed to pitch speed ratio result has been added, thanks to the EFO member comments. It was taken care of in the original formulas and process, but it can now be 'seen.' Speaking of Stall Speed to Pitch Speed Ratios     A direct quote from Keith Shaw's "Electric Sport Scale" article in Model Builder about stall speed: "In order to just do a nice inside loop, the plane must enter at twice the stall speed. To do clean inside loops, rolls, and other sport-type aerobatics, three times stall speed is needed.     Anything over 4 times the stall speed gives 'fighter-type"' performance and extended vertical aerobatics."      Note that Keith uses the word speed, NOT pitch speed. Pitch speed can be estimated, and the 'real' speed will, in most instances, be less to quite a bit less, depending on the airframe, but the pitch speed to stall speed ratio gives a decent 'hint' about the "flyability" of a given prop propelled plane. A comment on 'low' pitches:      Bob Boucher's quote on prop pitches from the AstroFlight, Inc. Electric Motor Handbook, "Thirdly please note that at almost all usable speeds one never wants to use a propeller with a pitch to diameter ratio less than 0.5. VERY LOW PITCH PROPS like a 9x3, 12x4, 18x6 and 24x8 are best used for stirring paint."      Of course this was written before 3D and 'hovering' entered the scene and prop thrust became almost as important as the pitch speed to stall speed ratio for that type of flying.      A pitch selection area was added to the Excel spreadsheets.      The diameter selection no longer requires either the plans or plane to be 'in hand'.      There are two spreadsheets in the Excel workbook to cover using Li-Poly and "A123" 2300mAh batteries for glow conversion. There is another spreadsheet for taking notes about possible motors. The fourth spreadsheet was done before Toledo when I was deciding on a new .60 size plane for use with the "A123" 2300mAh cells. Some don't have an appropriate motor for use with these batteries. They would have appropriate motors for Li-Poly cells, but I was not interested in that. Web sites noted at the meeting: RC Model Reviews Electric Flyer Magazine RC Book      The video shown during the 'refreshment' part of the meeting was "15th Annual Mid America Electric Flies" by SKS Video Productions. It was taped at the 2001 Mid-Am and was really the 16th, but 15th sounded better in the title. Since the meeting:      I have reworked the Excel workbook many times. It now has a companion "How to" use the spreadsheets. An email from Arthur Deane about the spreadsheet: Rich,      Attached is a prediction of the required power system for your Spacewalker using Ken's new spreadsheet. We have been mystified how Ken and Lucien Miller could suggest changes to Kv to optimize performance. This prediction shows that they were both spot on in suggesting a rewound motor.      I am impressed with their genius!!! Ken,      Once again your spreadsheet has been vindicated and proven very effective. The spot checks at the EFO meeting and this prediction all prove it out. I think it will become a very useful tool.      As you know I have been trying to establish in my mind how and why recommendations are made to vary the Kv. This spreadsheet has shown the reason.      Basically you calculate input watts based on our traditional 100W/# with modifiers to take into consideration the original gas power plant and a factor based on cubic wing loading to account for the usage. Knowing the relationship between watts/horsepower/prop diameter and pitch the RPM may be calculated. From then on it is simple trial and error to find the best mix. Kv is a simple rpm/volts relationship and varies based on the RPM and battery pack chosen. I now see the light!      You have put a lot of work into this spreadsheet and it is a great tool. Regards AJ      Thanks Arthur. Glad you find it useful. KM Return to "What's In This Issue" RCCD WOW Meet Postponed From Mike Pavlock via email      The weather in southeastern Michigan has not been good for RC flying this year. So far, I've only been out flying three times! I did go to the Radio Control Club of Detroit WOW event on May 14, but elected not to fly in the overcast and drizzling weather with extremely poor visibility. The meet had been postponed by the time I arrived at 8:45. I received the following from Mike. KM WOW Participants,      Due to poor weather conditions we are sad to inform you that: Watts Over Wetzel...WOW...has been postponed.      We will not be flying Sunday May 15th.      We will reschedule WOW to a later date. The reschedule date will be advised as soon as it is known.      Please monitor your e-mail and visit the WOW Web page often for event updates.      Thank you for your patients.      We'd sure like some decent flying weather soon! KM Return to "What's In This Issue" RBC Kits From Rob Bulk info@rbckits.com      We are always looking for great kits, and Rob's great models have not been mentioned in the Ampeer in quite awhile! Too long! KM Hello Ken,      Would you please update the link and the logo for rbckits? We do not have a USA importer. We sell direct now. Greetings and thanks, R.Bulk computerfreeswerk www.rbckits.com      Above is just one of Rob's models. I highly recommend that you visit his site and see what else he has to offer it kit form. I'm sure you will be both surprised and pleased. KM Return to "What's In This Issue" Shoulder-wing Toledo Special From Jim Blanner via email Hi Ken!      Hope you're surviving the winter - build anything?      I scratched a fuselage for use with some Toledo Special feathers; hope it's a little faster! Video here      What values do you use in motor prediction programs for A123s; specifically the 1100s? TIA, Jim      Build anything? Worked on the An-2 design and mock-ups. Ran into several problems, so I will be starting again in the fall. Working on a 1/4-scale Balsa USA biplane right now, since the flying weather is so crummy!      When I talk about "A123" cells, I'm almost ALWAYS talking about the 2300mAh cells. I don't have any of the 1100mAh cells for any purpose; motor power or radio system power. KM Return to "What's In This Issue" A Foam Antonov An-2 From Dereck Woodward via email Hi Ken,      So what's all the fuss about this furrin' biplane you're building, or designing, or cussing at!      Saw this foamy at GP's E Fest, on one of the trade stands. They didn't have too many problems with it, they reckoned, but yours should look better.      At least you know it'll fly as a model now.      Saw your latest Ampeer with that new Lazy Bee fan's letter. Can send him some Bee-ish info if he's still interested - there's plenty on the Zone about the species these days.      Snow-bound and too much bad in the weather to go flying here too. Still planning on getting over your way this year, if the creek (or lake!) don't rise. Regards, Dereck Woodward Return to "What's In This Issue" Put This One On Your Event Schedule! Keith Shaw Birthday Party Electric Fly-In From Dave Grife grifesd@yahoo.com      The Balsa Butchers will once host the "Keith Shaw Birthday Party Electric Fly-In" at their field near Coldwater, MI. This is the 10th Anniversary of this event. The event will take place on June 4 and 5, 2011. Contest Director: Dave Grife - E-mail: grifesd@yahoo.com or Phone: 517.279.8445 Please e-mail or call with any questions The Flying Field will be open Friday, June 3 for early arrivals Saturday, June 4, hours are from 9 a.m. 'til 5 p.m. Sunday, June 5, hours are form 9 a.m. 'til 3 p.m. Landing Fee is $10 for the weekend. Directions: Quincy is approximately 4.5 miles east of I-69. Clizbe Road is approximately 1.6 miles east of Quincy. The Flying site is approximately 1.5 miles south of US-12 on the west side of Clizbe Road.

To Reach Ken Myers, you can land mail to the address at the top of the page. My E-mail address is: KMyersEFO@theampeer.org
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