Hmm am getting different readings when I use that calculator myself, have to find others. You don't need to know track length, I only used it because I could see it in the video and it sort of made it easy, but this online calculator says different. Have to find another I think to cross reference.
What you where doing is correct, you have a 9 inch drive wheel, mine is 3.5 so guessing you need a rotion about 170ish rpm if you wanted the same speed. On 3/3/09 3:32 PM, "Tango71" <[email protected]> wrote: > > My drive wheel is going to be 9" in diameter. Don't know if that > helps. I'm not sure about the length of my track though. I'd like to > somehow figure out how fast my tank will be. > > I used this calculator but not sure if wheeled vehicles and tracked > vehicles share the same math. > > http://wahiduddin.net/calc/calc_speed_rpm.htm > > I put 100 as my RPM 1:1 for both gear ratios and 9" for tire. The > calculation was 5.4mph which is approx 8.6kph but once again this is a > tracked vehicle so I'm not sure if the same rule applies. > > On Mar 2, 7:48 pm, George Mastoras <[email protected]> wrote: >> Motor no load speed is 5500, gear ratio is 12:1. >> >> I was aiming at 400 rpm for regular use, based on the rule of fours a bit. >> >> The only other factor is the size of your drive wheel with the track on. >> If your drive wheel is twice as large then you would only need half the rpm. >> >> On 3/3/09 2:27 PM, "Tango71" <[email protected]> wrote: >> >> >> >>> So what is the shaft RPM of those motors then? and what is the >>> gearing. Reason I ask is that I would like to get a bit more speed out >>> of my Tiger but my wheelchair motors at 24v only give me about 110RPM >>> They are all torque though so I may be able to gear them up a bit. >> >>> On Mar 2, 5:58 pm, George Mastoras <[email protected]> wrote: >>>> The wheel rpm is about 400 - 450 in theory. >>>> I worked out the speed by counting the track rotations from the video. >> >>>> Here is the maths I used >> >>>> 1.5 meters track length >>>> 54 turns per minute >>>> 54 x 1.5 = 81 meters per minute >>>> 6o minutes p hour 81 x 60 = 4.860 KPH >> >>>> under load 51 turns 76.5 >>>> 76.5 x 60 = 4.59 KPH >> >>>> Trying to work out what speed it needs to run to look scale. >>>> 72kph at 1/10th scale is I think 7.2kph?? Maybe. If that's the case I am >>>> too >>>> slow but somethings out somewhere I think. >> >>>> George >> >>>> On 3/3/09 12:28 PM, "Tango71" <[email protected]> wrote: >> >>>>> Got a question. What is the total wheel RPM at full speed? That looked >>>>> a lot faster than 5kph. >> >>>>> On Mar 2, 8:07 am, George Mastoras <[email protected]> wrote: >>>>>> Finished the final 8 wheels yesterday. In the evening decided as a break >>>>>> from the extreme boredom of grinding down plastic wheels to give it a run >>>>>> for a few minutes with freshly charged batteries. At the last minute >>>>>> grabbed >>>>>> the video camera. >> >>>>>> I was only going to let it run but as I saw a nut fall off the wheel I >>>>>> decided to push down onto it and test other things as well. >>>>>> From doing this video have learnt that it will do 5KPH without slowing >>>>>> down >>>>>> much, probably over most terrain and angles. I was putting a bit of force >>>>>> on >>>>>> and only one side was being tested at a time. >> >>>>>> This was only going to be seen by me so a few bad habits being shown, >>>>>> sticking motor wires into battery connectors while holding onto a vehicle >>>>>> probably isn¹t a good practice. >> >>>>>> George >> >>>>>> http://www.youtube.com/watch?v=bksbHnxaARA&feature=channel_page >> >> > > > --~--~---------~--~----~------------~-------~--~----~ You are currently subscribed to the "R/C Tank Combat" group. To post a message, send email to [email protected] To unsubscribe, send email to [email protected] Visit the group at http://groups.google.com/group/rctankcombat -~----------~----~----~----~------~----~------~--~---
