SEN 2745
- Need 6 cylinders to balance ?
- Wanted older F1A Electronic fuselages
- Updated Skyscraper Annual Schedule for June 27-28
Need 6 cylinders to balance ?
From:Peter Martin
I did wonder what Gil was angling at with his question on piston reversal. Now I see that he’s talking about “engine balancing”. So the answer to “Do these reversals lessen engine efficiency?” is No at the isolated instant of reversal ..provided that the counterbalancing mass equals the mass of piston, conrod, crankpin and opposing crankshaft mass.
But at any other instant (when the crankshaft is not top dead or bottom dead centre), the answer is Yes! It’s physically impossible to balance a single cylinder, as the counterbalancing mass also moves left-to-right as well as up-and-down. It’s that left-to-right movement that causes vibration and therefore inefficiency in a single cylinder reciprocating engine. Not to mention that the fuel only goes bang once per revolution in a two-stroke, so no combustion balance every half rev.
What Gil needs is a 6-cylinder engine.. With a Six, the primary and secondary harmonics can be balanced out to near-perfection. There are still higher order harmonics (vibrations at higher multiples of crank rotational frequency), but they’re small. So I look forward to seeing Gil’s 6 cylinder 2.5cc engine, it’s going to sound great!
Peter Martin
Wanted older F1A Electronic fuselages
From:Stuart Darmon
Does anyone out there have an old- school one or two servo F1A fuselage that they would be willing to part with for a reasonable price? I’m doing some experimenting at the moment and it would save me a lot of time to buy a couple ready to go. Must be BM timer and the normal pulley- type stab mover (rather than the ‘fork’ style).. In an ideal world I’d prefer a Kosonochkin one as I’m used to that layout, but that isn’t critical- but I do need it posted to the UK. If you can help, could you please contact me at stuartdarmonf1a@yahoo.com Many thanks.
Kind regards,
Stuart
Updated Skyscraper Annual Schedule for June 27-28
From:Andrew Barron
Dear FreeFlight Friends,
Attached please find the updated Skyscraper Annual Schedule for next
weekend June 27-28.
Following the success of the Skyscraper Hatschek International Challenge
last month, this upcoming Skyscraper Annual continues to give flyers
opportunity to participate in our cherished hobby and get important
exercise while respecting state guidelines on social distancing. Please
remember to maintain distance for the safety of others, not just yourself.
The schedule attached has been arranged by the CD Aram Schlosberg. To help
his management of the event, please notify him of your plan to come. His
contact information is on the schedule beloe.
Skyscraper’s Annual
American Cup/ National Cup
Wawaywanda, NY
Saturday and Sunday, June 27-28, 2020
Revised schedule
Saturday June 27th start 10 am
FAI events: F1C(power), F1H(glider), F1G(rubber), F1J+F1P(power), F1Q (Electric)
Sunday June 28th start 8 am
FAI events: F1A (glider), F1B(Wakefield) and F1S (Electric).
AMA events: E36, Electric A, Electric B, E 20, HL Glider, Cat. Glider, P-30 can be flown on either day.
All FAI events will have 5 rounds. Round lengths will be at least one hour.
Due to the COVID-19 epidemic flyers are required to maintain social distancing. Face masks are required, don them when appropriate. Please bring a pen to record your scores. Those using golf carts are encouraged to use gloves. Towels and cleaning materials are also recommended.
Entry fee is $25 for all events. Fuel donation $5. (Please bring the exact amount).
(Camping is possible on the field. Super 8 in Middletown is open as well as other motels. Directions to the field are on www.brooklynskyscrapers.org). You are welcome to come for either day or both days.
CD: Aram Schlosberg.
(917) 446 3222
aram.schlosberg1@verizon.net
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…………..
Roger Morrell