The future of 1/12 scale
10-16-2008, 08:07 PM
#16
I know of something cheaper to experiement with.... Take a 4-cell NIMH pack and solder off one cell to make a 3-Cell NiMH pack. Most old-school 1:12racers have rx packs but if you don't have one RC4Less.com has them for $10
10-16-2008, 08:14 PM
#17
If a lower voltage change happens for 1:12 or pan oval, you can bet $100 that by the start of following carpet season that high end ESC's will have DC-DC convertors instead of 5V regulators. And will a RX pack be a bad thing till the ESC's catch up? Nitro guys have been running them for many years.
10-16-2008, 08:29 PM
#18
I have first hand experience with a small 2 cell lipo and a small 380 BL motor mounted in a 12th scale on a medium bite carpet track similar in size to what is run at most big carpet races. I didn't try every motor out there, but I tried to find the least powerful ones I could. It was WAY WAY to fast. It provides a good speed for mod. I would be curious to know what motors would provide a slower than our current stock equivalent when paired with a 2 cell lipo. I even tried a 21.5 540 bl motor and it was also WAY WAY to fast for anyone but experienced seasoned veterans. I understand the prospect of a receiver pack is unpleasant to some. I think a bigger problem would be a 12th scale without a slow enough power package to allow newcomers to control the cars. Good racing is not about speed. The best racing I have ever enjoyed was running mabuchis.
We were talking about this last night at the track.
10-16-2008, 09:34 PM
#21
If a lower voltage change happens for 1:12 or pan oval, you can bet $100 that by the start of following carpet season that high end ESC's will have DC-DC convertors instead of 5V regulators. And will a RX pack be a bad thing till the ESC's catch up? Nitro guys have been running them for many years.
And that's not even considering the change in balance layout a 3 cell NiMh pack would require for the saddle pack guys who hadn't yet converted over to LiPo.
10-16-2008, 10:05 PM
#22
Let me just start by saying: go for it! Just don't buy the 8kv Mamba, it blows over! 
I estimated that it should be capable of 57mph indoors... it tried to get there!
I have this set up on a old pos link car that I scratched 10+years ago. It weighs a scant 14.5ou ready to roll. I bought a $9 mini-micro servo that steers just fine. A 1550mah 2c pack from Max Amps for roughly $25. The Mamba esc and motor pack for $125. Yep, doesn't cost that much. All the testing I did was on one set of worn out tires. They don't wear. I beat this thing senseless. Into the wall, drivers stand, pipes, other cars.... I never broke it. I then tested the 5400 which was still faster then a 3.5 with 4 cell. Then I went to a 3600 which slowed down significantly, about a slow 27t. The 4200 should be perfect, but I haven't bought one yet.
Here's the flaws in the grand plan: if it doesn't hook up on asphalt, you cut about 1/2 the 1/12th scale people out of the loop. Manufacturers will not get on board to design a car that will go out to half the people. Game over.
Yes, it will work on carpet. Yes, you will save a lot of money. And yes, it can go faster then you can handle.
Racers are stubborn, they don't want to invest in new products that have not been tried & trued and we have a fear of the unknown.
That still doesn't mean that it's a great idea. If we knew that a year from now, that was the description the future 12th scale..... we'd do it.
I will say this, that little car was more intense then my 8th scale car! It made me grin the entire time.
Brian
I estimated that it should be capable of 57mph indoors... it tried to get there! I have this set up on a old pos link car that I scratched 10+years ago. It weighs a scant 14.5ou ready to roll. I bought a $9 mini-micro servo that steers just fine. A 1550mah 2c pack from Max Amps for roughly $25. The Mamba esc and motor pack for $125. Yep, doesn't cost that much. All the testing I did was on one set of worn out tires. They don't wear. I beat this thing senseless. Into the wall, drivers stand, pipes, other cars.... I never broke it. I then tested the 5400 which was still faster then a 3.5 with 4 cell. Then I went to a 3600 which slowed down significantly, about a slow 27t. The 4200 should be perfect, but I haven't bought one yet.
Here's the flaws in the grand plan: if it doesn't hook up on asphalt, you cut about 1/2 the 1/12th scale people out of the loop. Manufacturers will not get on board to design a car that will go out to half the people. Game over.
Yes, it will work on carpet. Yes, you will save a lot of money. And yes, it can go faster then you can handle.
Racers are stubborn, they don't want to invest in new products that have not been tried & trued and we have a fear of the unknown.
That still doesn't mean that it's a great idea. If we knew that a year from now, that was the description the future 12th scale..... we'd do it.
I will say this, that little car was more intense then my 8th scale car! It made me grin the entire time.
Brian
10-16-2008, 10:31 PM
#23
2S Mabuchis in F1 average about 16 secs per lap vs 15secs per lap on 23Turn brushed / 13.5 BL stock TC in my club's track (smooth indoor asphalt) . I would estimate 2S Mabuchi powered 1/12 to match or even go slightly faster than the 13.5BL powered TCs.
Brian: Do the 380BLs mount straight onto the motor mount or did you need a different mount? Thanks.
10-16-2008, 10:43 PM
#24
Tech Fanatic
Balanced view, Slapmaster, thanks.
A piece of advice from a dedicated 12th racer (30 years) to those who want to change it - change your rhetoric. If you want people like me on board (dedicated 12th racer, fast-follower in most things new, early adopter in others, disposable income) then you have to stop telling me that there is something wrong with me for not immediately jumping on your bandwagon.
Words like stubborn, lost in the past, hating change, etc. just make me get on here and flame you. My Company works in a rapidly changing market, my role involves creating change, and the World around me is changing daily. My hobby, on the other hand, is relatively stable. I don't think I am unusual.
The big attraction of 12th is that it doesn't change. I don't have to be at all the big meetings making sure I know what the latest thing is, I don't have to worry about finding out what the latest thing does to my set-ups, etc. etc. My hobby is for fun, not for more hard work. If you want to make changes, for me, they are going to have to a lot easier than ripping everything out and replacing it all in one go.
And, it isn't that we don't promote and adopt change. Look here at what cars used to be like and tell me 12th hasn't changed. But look carefully and you find that each change came along slowly, and it didn't alienate half the drivers in one stroke. That's how 12th works, and has survived so long.
Big chunks of change don't suit everyone, and telling them they have some character flaw if they don't adopt some (badly thought through, in this case, as Slapmaster points out) radical change isn't your best marketing ploy. Sell to me by all means, but name-calling will make me hang up on you - and hundreds of others will do the same.
A piece of advice from a dedicated 12th racer (30 years) to those who want to change it - change your rhetoric. If you want people like me on board (dedicated 12th racer, fast-follower in most things new, early adopter in others, disposable income) then you have to stop telling me that there is something wrong with me for not immediately jumping on your bandwagon.
Words like stubborn, lost in the past, hating change, etc. just make me get on here and flame you. My Company works in a rapidly changing market, my role involves creating change, and the World around me is changing daily. My hobby, on the other hand, is relatively stable. I don't think I am unusual.
The big attraction of 12th is that it doesn't change. I don't have to be at all the big meetings making sure I know what the latest thing is, I don't have to worry about finding out what the latest thing does to my set-ups, etc. etc. My hobby is for fun, not for more hard work. If you want to make changes, for me, they are going to have to a lot easier than ripping everything out and replacing it all in one go.
And, it isn't that we don't promote and adopt change. Look here at what cars used to be like and tell me 12th hasn't changed. But look carefully and you find that each change came along slowly, and it didn't alienate half the drivers in one stroke. That's how 12th works, and has survived so long.
Big chunks of change don't suit everyone, and telling them they have some character flaw if they don't adopt some (badly thought through, in this case, as Slapmaster points out) radical change isn't your best marketing ploy. Sell to me by all means, but name-calling will make me hang up on you - and hundreds of others will do the same.
10-17-2008, 12:10 AM
#25
I've done a LOT of thinking and research on this and plan to put together a similar test hack. I will test 2s LiPo but will install a, comparatively, VERY slow motor. I found a company that makes a full line of 380 size brushless motors down to 34T. Unfortunately no one in the states carries them. I believe I finally located a source overseas that can get me a couple of these to play around with.
It's been a couple months since I was seriously looking at this...it got put on the back burner because there are a couple things about the idea(s) that I wanted to run past Bob Stormer who usually has some neat ideas about what's what. As luck has it he plans to be down to race with us this weekend so I dug out my info and look forward to sorting this out so I can get the motors ordered up.
The motor I'm looking at as a 4-cell/17.5 equivalent is a 380 size motor with a 48mm long can. This will JUST fit into a current motor pod with the requisite adapter to pick up the smaller mounting screw circle. Oh yeah, it also has a .125 shaft diameter which makes it work with our pinions rather than the ones for the micro cars.
According to Novak's published specs their SS17.5 Pro is a 2.2kv motor (THIS is why the 5.4-8.0kv motors commonly available for minis are too powerful). 2.2kv gives 10,560 rpm at 4.8 volts (the nominal 1/12 voltage). Divide that 10,560 rpm by 7.4v (nominal 2s LiPo voltage) and you get 1,427 rpm/volt (1.427kv if you prefer) as the desireable RPM that would give the same top speed potential. Sure enough, the 27T bl motor I'm looking at is listed as 1462 rpm/volt (1.462kv) and the 28T is 1410. Neatly bracketed.
Further, the Novak SS17.5 Pro is described as a 130 watt motor. Both the 27T and 28T motors on my short list are rated at 15 amps. 15 amps times 7.4 volts gives 111 watts which is not quite 15% less. This, it turns out, should be just ducky because my projected weight savings is approximately 25%. I think these would accelerate pretty much the same and have a similar top speed to the SS17.5 Pro.
Weights? The Novak motor is spec'd at 6.61oz (approx 187 grams). The motor I'm looking at weighs 136 grams. A bare Ener-G 4600 cell from SMC weighs 68.8 grams, four cells would be about 275 grams PLUS five battery bars and some solder. Figure 280g minimum? A MaxAmps 2000mah LiPo weighs in at 120g (add more once a hard case is added). That's a savings of about 211 grams, or approximately a 25% weight savings over my DB12R at race weight. I could add a bit of weight as necessary and STILL have a 15-20% lighter car.
Just some stuff in my head until I pull the trigger on the motors. I'll probably end up having to buy a few. We're not going to be going to 13.5 in SuperStock until our 2009-2010 season so if I want to compare with what we're running SuperStock this coming season I need a 10.5 equivalent which puts us in the 14-15T range for this mystery motor and yields approx. 207 watts compared with the SS10.5 Pro at 235watts.
The truly challenging part in this is that none of the current larger capacity LiPos will fit the space allowed--they're all just a hint too long for either my BMI or CRC chassied cars. Then again my Slider runs about forever on a 1550mah LiPo with an 8.0KV motor so I'm pretty sure the car I'm proposing would run just fine for 8 minutes (or more) on 2000 mah.
My biggest concern is the low speed/accelerating from rest performance from such a high wind motor in a sensorless application. I will probably use one of my Tekin Mini-Rage esc's for these experiments. I would DEFINITELY prefer something like the Mongoose but, again, the lowest spec motor is still WAY too much for what we're talking about here.
Anybody see obvious flaws in my reasoning? I'd sure like to find any that might be lurking here before I commit a couple-three hundred bucks to the idea.
Scottrik
It's been a couple months since I was seriously looking at this...it got put on the back burner because there are a couple things about the idea(s) that I wanted to run past Bob Stormer who usually has some neat ideas about what's what. As luck has it he plans to be down to race with us this weekend so I dug out my info and look forward to sorting this out so I can get the motors ordered up.
The motor I'm looking at as a 4-cell/17.5 equivalent is a 380 size motor with a 48mm long can. This will JUST fit into a current motor pod with the requisite adapter to pick up the smaller mounting screw circle. Oh yeah, it also has a .125 shaft diameter which makes it work with our pinions rather than the ones for the micro cars.
According to Novak's published specs their SS17.5 Pro is a 2.2kv motor (THIS is why the 5.4-8.0kv motors commonly available for minis are too powerful). 2.2kv gives 10,560 rpm at 4.8 volts (the nominal 1/12 voltage). Divide that 10,560 rpm by 7.4v (nominal 2s LiPo voltage) and you get 1,427 rpm/volt (1.427kv if you prefer) as the desireable RPM that would give the same top speed potential. Sure enough, the 27T bl motor I'm looking at is listed as 1462 rpm/volt (1.462kv) and the 28T is 1410. Neatly bracketed.
Further, the Novak SS17.5 Pro is described as a 130 watt motor. Both the 27T and 28T motors on my short list are rated at 15 amps. 15 amps times 7.4 volts gives 111 watts which is not quite 15% less. This, it turns out, should be just ducky because my projected weight savings is approximately 25%. I think these would accelerate pretty much the same and have a similar top speed to the SS17.5 Pro.
Weights? The Novak motor is spec'd at 6.61oz (approx 187 grams). The motor I'm looking at weighs 136 grams. A bare Ener-G 4600 cell from SMC weighs 68.8 grams, four cells would be about 275 grams PLUS five battery bars and some solder. Figure 280g minimum? A MaxAmps 2000mah LiPo weighs in at 120g (add more once a hard case is added). That's a savings of about 211 grams, or approximately a 25% weight savings over my DB12R at race weight. I could add a bit of weight as necessary and STILL have a 15-20% lighter car.
Just some stuff in my head until I pull the trigger on the motors. I'll probably end up having to buy a few. We're not going to be going to 13.5 in SuperStock until our 2009-2010 season so if I want to compare with what we're running SuperStock this coming season I need a 10.5 equivalent which puts us in the 14-15T range for this mystery motor and yields approx. 207 watts compared with the SS10.5 Pro at 235watts.
The truly challenging part in this is that none of the current larger capacity LiPos will fit the space allowed--they're all just a hint too long for either my BMI or CRC chassied cars. Then again my Slider runs about forever on a 1550mah LiPo with an 8.0KV motor so I'm pretty sure the car I'm proposing would run just fine for 8 minutes (or more) on 2000 mah.
My biggest concern is the low speed/accelerating from rest performance from such a high wind motor in a sensorless application. I will probably use one of my Tekin Mini-Rage esc's for these experiments. I would DEFINITELY prefer something like the Mongoose but, again, the lowest spec motor is still WAY too much for what we're talking about here.
Anybody see obvious flaws in my reasoning? I'd sure like to find any that might be lurking here before I commit a couple-three hundred bucks to the idea.
Scottrik
10-17-2008, 12:14 AM
#26
I am probably not the guy to ask on this topic, because I don't really want to see change in 1/12 scale, but if I were to pick, I'd choose the 2 cell/small motor concept over the single-cell and receiver pack option. I've tried receiver packs at various times over the years (and I've been actively racing 1/12 since 1979) and I';ve never had much of anything good to say about them.
I've seen Roland's car run, and I've driven it myself, and the concept works.
Just my own opinion here...
I've seen Roland's car run, and I've driven it myself, and the concept works.
Just my own opinion here...
10-17-2008, 12:31 AM
#27
Roland,
Thanks for bringing up a great topic. You have obviously given this much thought.
I once tried 1 cell lipo and it was too slow (for me) regardless of motor. Driving full wood all the time was boring.
I once tried 2 cell with 540 sized motors and it was too fast....silly fast. Unraceable.
Here's another thing to try. A123 makes a 18650 sized battery rated at 1100mAh that is only about 3 volts. It's super safe, has great current capability, and great cycle life. You can build a 2S2P pack for a total of 2200mAh at 6V or maybe try to fit in a 2s3p pack for 3300mAh at 6V.
It would be the same voltage as 4 cell NIMH. No changes to the motor or rear pod. The graphite chassis may eventually need mods, but that's minor since cutting graphite is not exactly a mass production operation.
Thanks for bringing up a great topic. You have obviously given this much thought.
I once tried 1 cell lipo and it was too slow (for me) regardless of motor. Driving full wood all the time was boring.
I once tried 2 cell with 540 sized motors and it was too fast....silly fast. Unraceable.
Here's another thing to try. A123 makes a 18650 sized battery rated at 1100mAh that is only about 3 volts. It's super safe, has great current capability, and great cycle life. You can build a 2S2P pack for a total of 2200mAh at 6V or maybe try to fit in a 2s3p pack for 3300mAh at 6V.
It would be the same voltage as 4 cell NIMH. No changes to the motor or rear pod. The graphite chassis may eventually need mods, but that's minor since cutting graphite is not exactly a mass production operation.
10-17-2008, 01:21 AM
#28
I really like the 2 cell and 380 size motor idea...when you think past the conversion to what it eventually would be come, a purpose built 2 cell 380 motor would have a pod at least 30% smaller if not more and definately lower, more chassis room to move electronics and batteries around to find their ultimate balance point. All on a chassis with a much lower profile which opens up more body design possibilities, hopefully ones that look much more scale to the car they are copying. Don't get me wrong I think the bodies we have now look good...just don't have the scale looks I'd love to see and run. When I first got into 1/10th pan that is one of the things I loved most about the cars were some of the beautiful bodies out there...the Bud Light Jag, the Andy's 962 and more that I just can't think of off-hand. Tamiya still manages to make some incredibly scale 1/10th pan car bodies for their chassis...I'd love to see that kind of detail come to 1/12th as well.
10-17-2008, 01:44 AM
#29
..... Don't get me wrong I think the bodies we have now look good...just don't have the scale looks I'd love to see and run. When I first got into 1/10th pan that is one of the things I loved most about the cars were some of the beautiful bodies out there...the Bud Light Jag, the Andy's 962 and more that I just can't think of off-hand. Tamiya still manages to make some incredibly scale 1/10th pan car bodies for their chassis...I'd love to see that kind of detail come to 1/12th as well.
10-17-2008, 04:05 AM
#30
Tech Adept
2S-Lipo with Brushless 380 sounds good. For Racers who don't like speed, there are also brushed mabuchi 380 motors available 
Hm, I saw a Lipo 380-Brushless 12th scaler on youtube, but don't remember its name. Does anyone know this vid?
If the cars need more weight. replace the graphite parts through glassfiber parts and the aluminium screws through steel screws. That will also keep the costs down.
Hm, I saw a Lipo 380-Brushless 12th scaler on youtube, but don't remember its name. Does anyone know this vid?
If the cars need more weight. replace the graphite parts through glassfiber parts and the aluminium screws through steel screws. That will also keep the costs down.