Re: [RCSE] Servo calculator
The link to it from the main page seems to be gone but the page is still where it used to be: http://www.multiplexrc.com/calcservo.htm The old web site is still accessible at http://www.multiplexrc.com/home.html, not sure if the 'products' link should actually link to that page. Frank - Original Message - From: Stan Koch [EMAIL PROTECTED] To: MAN [EMAIL PROTECTED] Sent: Saturday, March 01, 2003 2:21 PM Subject: [RCSE] Servo calculator Which site provides servo application chart. Karlton' did b I can not locate it. Thanks...STAN RCSE-List facilities provided by Model Airplane News. Send subscribe and unsubscribe requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. RCSE-List facilities provided by Model Airplane News. Send subscribe and unsubscribe requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off.
[RCSE] servo calculator
Greetings! One of the really neat things about the Multiplex web page is the calculator that will help predict the right sized calculator for an application. check out: http://www.multiplexrc.com/calcservo.htm OK, given that it is an approximation at best, I still get some really strange numbers. I'm probably using it wrong. Given your basic 125" sailplane. weighs say 70 oz, flaps are 2x25 inches, they deflect 90 degrees, the wing has a 10" chord and the plane is moving at say 75 mph. Yes, this is fast, but not unreasonable for a dive. For me the servo calculator gives a required servo of 112 in oz. This is a huge servo. Most of us would find a Hitec 225 MG with 55 in oz adequate. On the other hand, given an aileron on the same plane, again say 2"x25" that moves only 30 degrees then the required servo must carry only 37 in oz and an HS 85 at 42 in oz.is more than adequate. Am I doing this right? Whenever I try to come up with a value for flaps, it always seems about twice as high as folks use successfully. What am I missing? Thanks, Bill RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
Re: [RCSE] servo calculator
Bill, No disrespect intended, but what you're not doing right is pulling full flaps at 75 mph. Most full-house planes thermal around at 20-30 mph. First go out and fly your plane. Get it nice and high and [ut your plane in a dive to get the airspeed to 75 mph. Then pull full flaps... suddenly. Tell us what happens. BTW, don't try this anywhere near the ground. I guarantee that any elevator compensation you have programmed in will be completely wrong. After you try it, I am willing to be corrected. But I believe 75 mph is not a reasonable speed to expect a flap servo to hold up. I've done it at high speeds before and it is not fun. Jon Stone One of the really neat things about the Multiplex web page is the calculator that will help predict the right sized calculator for an application. check out: http://www.multiplexrc.com/calcservo.htm OK, given that it is an approximation at best, I still get some really strange numbers. I'm probably using it wrong. Given your basic 125" sailplane. weighs say 70 oz, flaps are 2x25 inches, they deflect 90 degrees, the wing has a 10" chord and the plane is moving at say 75 mph. Yes, this is fast, but not unreasonable for a dive. For me the servo calculator gives a required servo of 112 in oz. This is a huge servo. Most of us would find a Hitec 225 MG with 55 in oz adequate. On the other hand, given an aileron on the same plane, again say 2"x25" that moves only 30 degrees then the required servo must carry only 37 in oz and an HS 85 at 42 in oz.is more than adequate. Am I doing this right? Whenever I try to come up with a value for flaps, it always seems about twice as high as folks use successfully. What am I missing? RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
Re: [RCSE] servo calculator
Possibly the calculator is haveing a problem with the extreme deflections of the flap function,(90 degrees). I also think that you are using some unresonable numbers as far as speed. 75mph is not an unresonable number as far as speed of some planes, but I know when I pull flaps on my TD ship I am not normally going anywhere near 75mph. I do sometimes dive down from altitude but do not come screaming in and drop the flaps at that speed. If I have time and have planned things right I may pull on flaps first and spiral down slowly. In this case the flaps come in with very little speed and then pull out and off the flaps. Also when making the landing approach it is not at the extreme speeds you are referring to. I am using Hitec HS-225MG servos, one on each flap and as you have said they are up to the task for a 65 - 70 oz. Unlimited plane. Try inputting some smaller value for speed and see where the torque values come in about 45 oz. RB Bill Johns wrote: Greetings! One of the really neat things about the Multiplex web page is the calculator that will help predict the right sized calculator for an application. check out: http://www.multiplexrc.com/calcservo.htm OK, given that it is an approximation at best, I still get some really strange numbers. I'm probably using it wrong. Given your basic 125" sailplane. weighs say 70 oz, flaps are 2x25 inches, they deflect 90 degrees, the wing has a 10" chord and the plane is moving at say 75 mph. Yes, this is fast, but not unreasonable for a dive. For me the servo calculator gives a required servo of 112 in oz. This is a huge servo. Most of us would find a Hitec 225 MG with 55 in oz adequate. On the other hand, given an aileron on the same plane, again say 2"x25" that moves only 30 degrees then the required servo must carry only 37 in oz and an HS 85 at 42 in oz.is more than adequate. Am I doing this right? Whenever I try to come up with a value for flaps, it always seems about twice as high as folks use successfully. What am I missing? Thanks, Bill RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
Re: [RCSE] servo calculator
Just did some quick calculations on the servo calc program and if you drop the speed value down to 50 - 55 mph you will come in around the 55oz torque value of the HS-225's. I still feel this is too high a speed to be pulling full flaps for normal TD flying. RB Bill Johns wrote: Greetings! One of the really neat things about the Multiplex web page is the calculator that will help predict the right sized calculator for an application. check out: http://www.multiplexrc.com/calcservo.htm OK, given that it is an approximation at best, I still get some really strange numbers. I'm probably using it wrong. Given your basic 125" sailplane. weighs say 70 oz, flaps are 2x25 inches, they deflect 90 degrees, the wing has a 10" chord and the plane is moving at say 75 mph. Yes, this is fast, but not unreasonable for a dive. For me the servo calculator gives a required servo of 112 in oz. This is a huge servo. Most of us would find a Hitec 225 MG with 55 in oz adequate. On the other hand, given an aileron on the same plane, again say 2"x25" that moves only 30 degrees then the required servo must carry only 37 in oz and an HS 85 at 42 in oz.is more than adequate. Am I doing this right? Whenever I try to come up with a value for flaps, it always seems about twice as high as folks use successfully. What am I missing? Thanks, Bill RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
Re: [RCSE] servo calculator http://www.multiplexrc.com/calcservo.htm
Do the same calculation with say 15 degrees at 75 MPH enough to START to slow you down. Then 30 at say 25 MPH http://www.multiplexrc.com/calcservo.htm The 90 at 10 MPH for landing. http://www.multiplexrc.com/calcservo.htm Your back in the MICRO servo hunt and more like real world flying. Smooth Sailing, Karlton Spindle http://www.MultiplexRC.com Team Multiplex World F3J Champions USA F3B Champion USA F3J Champion USA Open Class Champion USA 1:5 Scale R/C car Touring Champions USA 1:5 Scale R/C car GT Champions RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
[RCSE] servo calculator: part 2
At 08:57 PM 10/5/00 -0500, Jon Stone wrote: No disrespect intended, but what you're not doing right is pulling full flaps at 75 mph. Most full-house planes thermal around at 20-30 mph. Wow! about 5 response in 15 minutes. Why aren't you guys watching the political debates??? OK, I see my problem. No, I would never actually do that, i.e. drop flaps at full dive. We have one guy around here who does that every now and then at a contest. Amazing how far the sound of an exploding wing will carry. Amazing how much energy you can store in a foam/glass wing to make that much noise. ;-) My problem was that I was playing with a computer. With this kinda calculating power it is easy to play "what if" games and I was setting up a totally unreasonable, worst case scenario. I stand corrected and I am using the servo calculator correctly, just not using reasonable numbers. Thanks to all who responded and to Karlton for making such a neat program available. Bill RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
[RCSE] servo calculator: part 3
At 07:33 PM 10/5/00 -0700, Bill Johns wrote: My problem was that I was playing with a computer. With this kinda calculating power it is easy to play "what if" games and I was setting up a totally unreasonable, worst case scenario. Actually I know better. Whenever I fly commercial I prefer a seat over the wing section so I can watch all the bits and pieces move while the pilot is doing all the serious work. I remember fondly noting that once at the initial stages of a descent, the pilot had to bank and I watched the ailerons move perhaps a very small amount, an inch a the outside, to produce a very quick movement of the plane. This was at a high speed. Later, while on final, at a much lower speed, the ailerons were moving many inches to correct for turbulence, and the plane sorta responded in its own sweet time. Same sorta thing we are talking about here. Back to the regularly scheduled programming. Bill RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
