I'm planning on building a 1:8 scale tank from scratch.
Approximately what sort of rpm for the drive sprocket should I be aiming for?
Thanks.
Also,
BT series tanks don't actually have a toothed drive sprocket. What's the correct term. A drive wheel?
RPM
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If your question is electronics related please post it in one of the relevant boards here: viewforum.php?f=31
- HERMAN BIX
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Re: RPM
The BT 7 had a top speed off road of 50 Kph so that divided by 16 gives you a scale max marker of 3.125kph
If you count the rotations of your drive wheel (mark it with a suitable visual line like white paint pen) over 15 seconds then multiply that by 4 to get the rpm in real time/per minute, then calculate that into the 3.125 kph you can adjust your gear ratio as required.
I reckon a bloke that can use a dividing head to great effect can easily work the maths on that
You may need to use an idler gear to slow down or speed up , really depends on what your gearbox is at the moment
If you count the rotations of your drive wheel (mark it with a suitable visual line like white paint pen) over 15 seconds then multiply that by 4 to get the rpm in real time/per minute, then calculate that into the 3.125 kph you can adjust your gear ratio as required.
I reckon a bloke that can use a dividing head to great effect can easily work the maths on that
You may need to use an idler gear to slow down or speed up , really depends on what your gearbox is at the moment
HL JAGDPANTHER,HL TIGER 1,HL PzIII MUNITIONSCHLEPPER, HL KT OCTOPUS,HL PANTHER ZU-FUSS,HL STuG III,HL T34/85 BEDSPRING,
HL PZIV MALTA,MATORRO JAGDTIGER,HL F05 TIGER,TAMIYA KT,HL PANTHERDOZER,HL EARLY PANTHER G,TAIGEN/RAMINATOR T34/76,
HL AN-BRI-RAM SU-85
HL PZIV MALTA,MATORRO JAGDTIGER,HL F05 TIGER,TAMIYA KT,HL PANTHERDOZER,HL EARLY PANTHER G,TAIGEN/RAMINATOR T34/76,
HL AN-BRI-RAM SU-85
Re: RPM
Dead on!
Drive wheel is the best general term as there are some vehicles out there that have both a toothed drive wheel and a toothed idler wheel, Churchill for example.
Panther Ausf D (WIP)
Panther Ausf A mit Brückentafel (WIP)
Panther Ausf G (WIP)
Jagdpanther G2 (WIP)
Tiger II (WIP)
Pz.Kpfw. VIII Maus V2 (WIP)
Pz.Kpfw. II Ausf L (WIP)
Sd.Kfz. 234/2 (WIP)
Leopard 1A4/1A1A1 (WIP)
Turm III (WIP)
VK 45.01 (H) (WIP)
Panther Ausf A mit Brückentafel (WIP)
Panther Ausf G (WIP)
Jagdpanther G2 (WIP)
Tiger II (WIP)
Pz.Kpfw. VIII Maus V2 (WIP)
Pz.Kpfw. II Ausf L (WIP)
Sd.Kfz. 234/2 (WIP)
Leopard 1A4/1A1A1 (WIP)
Turm III (WIP)
VK 45.01 (H) (WIP)
Re: RPM
Ok thanks,
I didn't know that about working out scale speed.
So. To achieve an actual speed of 3.125 kph ,
I will have a drive wheel 80mm diameter, that will be laying down track at a rate of 0.251 mtr per revolution
So to cover 3.125 km it needs to revolve 12450 times (in one hour).
Divide by 60 mins gives 207.5 rpm.
I think.
I didn't know that about working out scale speed.
So. To achieve an actual speed of 3.125 kph ,
I will have a drive wheel 80mm diameter, that will be laying down track at a rate of 0.251 mtr per revolution
So to cover 3.125 km it needs to revolve 12450 times (in one hour).
Divide by 60 mins gives 207.5 rpm.
I think.
- HERMAN BIX
- Brigadier
- Posts: 10385
- Joined: Sun Jan 12, 2014 12:15 am
- Location: Gold Coast,Australia
Re: RPM
If your math's is right , and Im sure it is, thats for the maximum top speed off road .
Depending on your gearbox set up, you may need to allow a different ratio so you get the best drivability at realistic control levels with the overall weight of your creation taken into account.
You can always drive it slower if required!!............
Depending on your gearbox set up, you may need to allow a different ratio so you get the best drivability at realistic control levels with the overall weight of your creation taken into account.
You can always drive it slower if required!!............
HL JAGDPANTHER,HL TIGER 1,HL PzIII MUNITIONSCHLEPPER, HL KT OCTOPUS,HL PANTHER ZU-FUSS,HL STuG III,HL T34/85 BEDSPRING,
HL PZIV MALTA,MATORRO JAGDTIGER,HL F05 TIGER,TAMIYA KT,HL PANTHERDOZER,HL EARLY PANTHER G,TAIGEN/RAMINATOR T34/76,
HL AN-BRI-RAM SU-85
HL PZIV MALTA,MATORRO JAGDTIGER,HL F05 TIGER,TAMIYA KT,HL PANTHERDOZER,HL EARLY PANTHER G,TAIGEN/RAMINATOR T34/76,
HL AN-BRI-RAM SU-85
- Herr Dr. Professor
- Lieutenant
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- Location: Southern Wisconsin USA
Re: RPM
"ome vehicles...have both a toothed drive wheel and a toothed idler wheel, Churchill for example." Why the toothed idler? Does it help keep tracks on more securely?