RE: solder won't stick...
[quote]ORIGINAL: michaelob78 well yeah if you are using plumbing flux.... i was talking about electronic flux [/quote] Right...except for some highly specialized applications, any electronic flux will be a rosin flux and shouldn't be corrosive. But if you're using a rosin-core solder you don't need any more flux added.
Posted on: 10/2/2005 4:28 PM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=3415032

RE: solder won't stick...
[quote]ORIGINAL: michaelob78 [quote]ORIGINAL: Graystar NEVER use a separate flux with rosin core solder! First, other types of flux will corrode your joints. [/quote] I solder all the time and never heard that one, the flux in the solder is the same stuff. Applying a little to start gives solder a clean spot to grab.[/quote] It's not the same stuff. Rosin-core solder for electrical joints
Posted on: 10/2/2005 1:52 PM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=3414691

RE: solder won't stick...
"it was all shiny to start with" So then you didn’t clean it... NEVER use a separate flux with rosin core solder! First, other types of flux will corrode your joints. Second, other types of flux are generally made for higher temperatures and won’t work properly unless you are overheating the parts. Soldering is all about heat transfer. The transfer has to be large but quick. Batteries are a good place to practice because they can absorb a lot of heat without damage. First, insure the operation of the iron. Remove the tip and sand two areas. Sand the actual tip of the iron with sandpaper. Also sand the area that gets screwed down in the iron. Next step is to heat up the iron and tin the tip. Let the iron get hot then put rosin core solder all over the tip. Then wipe the tip off on a wet sponge. At this point you’re ready to solder. Have a wet sponge nearby when soldering to repeat this procedure periodically. After wiping, wait at least 5 seconds to let the tip get back up to temperature. With battery and bar in place, press down on the bar with the soldering iron, making sure that some part of the hot tip is on or close to an edge of the bar. Then touch the solder to the hot tip and let about 3/4“ to 1� of solder flow onto the tip. The solder will flow onto the tip, down onto the bar, then down onto the battery. Here’s the important part...hold the iron in place and count 5 Mississippis. This is very important. You must allow time to heat the surface of the cell if you want the solder to stick. After a 5 count remove the iron and wait 30 seconds before doing the other side. That will give it time to cool enough to not be affected by soldering the other side. You know your soldered joints are good when intersection between two parts looks like a something you glued and ran your finger along it to smooth the glue line. This is referred to as a concave fillet and is the sign of a good joint. good luck!
Posted on: 10/2/2005 8:46 AM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=3414062

RE: New Radio!
According to the link, Tower has discontinued carrying the radio.
Posted on: 6/5/2005 10:05 PM by Author "Graystar" in the forum "RC Car Radio Equipment"
http://www.rcuniverse.com/forum/fb.asp?m=3045436

RE: digital or analog servos
[quote]ORIGINAL: o.s 21vspec could somone please shed some light on what or if there are any advantages on using digital servos,do they hold there posistion better under pressure?[/quote] To answer the original question... Yes, digital servos are better than analog because they have a much quicker reaction time. This allows them to hold their position better and to react faster to signal inputs. An analog servo feeds off of the input signal. That signal acts as the director for all action in the servo. A digital servo, however, has a computer that directs the servo activity. The signal is simply an input into the computer. The computer then decides what to do. So the computer will send adjustments to the servo motor at a greater rate than the analog signal. This lets the servo hold it's position better.
Posted on: 5/31/2005 9:14 PM by Author "Graystar" in the forum "RC Car Radio Equipment"
http://www.rcuniverse.com/forum/fb.asp?m=3030350

RE: cell count for racing.. what is allowed
Many many years ago, stock racing was 6 cell and modified was 7 cell. But the rules were changed at some point, and now I believe all car racing is 6 cell. Any good track will run their races according to ROAR rules. That's why battery packs from Trinity and other car-oriented companies are 6 cell. In fact, two of the best esc made, the Novak GT7 and GTX are only rated for 4-6 cell use. However, the majority of esc out there will work with 7 cells, and usually more. That's because boats usually take 7 cells, and other types of events use different cell counts.
Posted on: 5/21/2005 12:37 PM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2996678

RE: speeding
[quote]ORIGINAL: S.A.E.W.O.T. yea but them 17t's pull not even 30,000 rpms... a 7 will pull easy 55,000+ rpms [/quote] But it's not as simple as comparing rpms. Each revolution of the 55k rpm motor has less torque than each revolution of the 30k rpm motor. That is why you have to reduce the pinion size as motor rpms increase. Overall, the increase in rpms is greater than the drop in torque, and that gives you more power. But it's the complex relationship between rpm and torque that makes choosing a motor as important as choosing pinion size or tires.
Posted on: 5/21/2005 12:25 PM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2996666

RE: speeding
[quote]ORIGINAL: S.A.E.W.O.T. only 50% more power?....wow man that sux... them 17ts imo r crap [/quote] It's all relative. Personally I think 50% is a great accomplishment.
Posted on: 5/21/2005 12:20 PM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2996655

RE: speeding
You can go faster with a top quality expensive modified motor, but it probably won’t be the big increase you’re looking for. Speed is a function of available power vs. resistance. You go faster by increasing power or by lowering resistance. On-road cars have very low resistance... 1/12 scale cars can hit 65 mph with off-the-shelf components. Off-road cars have a lot more resistance and top out at 35 mph. According to Trinity’s spec chart, their 7 Turn motor has about 50% more power than their 17 Turn motor. However, that will NOT make you go 50% faster. Resistance is a funny thing...for example, wind resistance is a cube function…so to go twice as fast requires nine times the power! In the same way, buggy/truck tires and other factors make it impossible to get increases in speed that are proportional to increases in power. To get an off-road car up in the 30s, not only do you need the best car, but it needs to be assembled by a pro to insure the least possible amount of resistance. If you’re not racing, I think adding cells to the battery pack is the best way to increase speed. Just make a 7-10 cell pack if your esc can handle it. That will probably do a lot more than a better motor, and will probably last longer. What you DON’T want to do is increase the pinion size. There is no way a larger pinion can get more power out of motor. There’s a point where a motor is simply giving you all it has, and there’s nothing more to do about it. A larger pinion just burns it out.
Posted on: 5/21/2005 12:13 PM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2996640

RE: Problem With Team Associated B3
We need more information in order to help you. Never say never, but I think it’s highly unlikely that either the esc or motor is causing the problem. What you’re describing is a radio problem. But you said nothing about the radio. Did the B3 come with a radio? Did you swap the radio? Did you drive the B3 before taking it apart? If you are using the radio that came with the B3, and you didn’t check it before taking it apart, then this problem could have been there all along. Try swapping the radio and see if you still have the problem. What we need to know to help you... Did the B3 come with a radio? What kind? FM or AM? What channel? What kind of radio is in the tl01? FM or AM? What channel? How is the receiver antenna routed in the B3? Does the 11 turn motor have capacitors mounted? What kind of connectors are you using? Bad connectors can cause radio problems.
Posted on: 5/21/2005 10:46 AM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2996484

RE: tips for soldering.....
Just get Deans Racing Solder with ProFlux. Then you'll know you have the best solder for this application.
Posted on: 5/13/2005 6:20 AM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2970654

RE: Mystery Solved! How to select the proper gearing for your electric RC!
[quote]ORIGINAL: ronnerwin The problem I had is that a scalar value (tire circumference measured exclusively in inches) is subtracted with a constant (final drive ratio) to yield another constant (the tire/gear ratio). ... Normally, you can’t do this kind of math because the units cannot cancel out to produce a non-scalar result; that is why the “ratio� calculation doesn’t apply to metric units without first converting to imperial. However, just because the math doesn't make sense, doesn’t mean the method doesn’t either. [/quote] Exactly. But more importantly, it means that the process isn’t understood. And if you don’t understand something then it can be misapplied, as in the case of touring cars and larger, heavier monster trucks. [quote]ORIGINAL: ronnerwin As mentioned in the original post, 1 to 1 (rollout value of 1 inch/rev or 25.4 mm/rev) is ideal. [/quote] Why do you say this? Where is this written (other than in this thread?) This assumption is the primary problem with this method. The assumption is only true for stadium trucks with mild modified motors. For buggies and trucks with stock motors, it under-gears the car. For 9 or 7 turn motors, it over-gears the car...possibly to the point of damaging the motor. For a monster truck used for backyard bashing...fine for stock motors but definitely over-gears with modified motors. Basically that means that there’s nothing ideal about the 1-to-1 relationship. I know that everyone wants a simple formula for gearing but the situation is simply too complex for that. We have different cars of different weights designed for different types of roads running with different motors...there’s simply no way a single formula will account for all these factors. We shouldn’t let our desire to have one formula blind us to the point of accepting something without understanding its limitations. The formula is just fine for stadium trucks, and won't hurt your buggy. It won't hurt your touring car either, but everyone else will be lapping you. It's fine for a monster truck with stock or mild modified motors. If you understand these limitations, and adjust accordingly, then the formula can serve you well. But if a person doesn't understand the limitations then they're rolling the dice on their motor...expecially expensive low-turn motors.
Posted on: 4/28/2005 9:55 AM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2922476

RE: Problem
Part number 55802, available from Tower Hobbies for $1.10. http://www2.towerhobbies.com/cgi-bin/WTI0095P?FVSEARCH=55802&FVPROFIL=++
Posted on: 4/24/2005 11:20 AM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2907741

RE: Mystery Solved! How to select the proper gearing for your electric RC!
[quote]ORIGINAL: SkrapIron The rationale behind the formula is this...[/quote] Well I guess that says it all.
Posted on: 4/12/2005 10:56 AM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2869021

RE: Mystery Solved! How to select the proper gearing for your electric RC!
[quote]You can see that in his change from the first post ( It can't work) to now ( It MIGHT work for trucks and buggies ).[/quote] Ah, now I see the problem here. You're not fully reading my posts. In my first post I simply questioned the rational behind the formula. I never said it can’t work. In my second post I said that it works only for stadium trucks, which I still believe. It will under-gear a buggy, but that shouldn't damage anything. And it doesn’t matter how long you’ve been in RC...wrong information is wrong information, and those statements you made were wrong. Bad information only increases confusion. [quote]What I find comical is now he's suggesting that someone take a ruler, and pace off the roll out of the tire, to essentially duplicate the formula. [/quote] So you're just dismissing it without trying it? Interesting...
Posted on: 4/11/2005 8:19 PM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2867062

RE: Mystery Solved! How to select the proper gearing for your electric RC!
(Moved here in the interest of maintaining context and not hijacking a thread) [quote]ORIGINAL: SkrapIron [quote]ORIGINAL: Graystar Don’t you have the manual? Get it from Associated here: http://www.teamassociated.com/shusting/CatalogHub/cathub_offroad.htm The B4 manual says to use a 22T pinion..., Graystar. Most of these guys who ask these questions either: 1: Do not yet have the model
Posted on: 4/11/2005 1:56 PM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2865746

RE: a racers opinion on a rear one way?
A rear oneway would be the equivalent of a one-wheel drive while taking turns. I don't know if this is a good thing or a bad thing. On the one hand, when taking a turn centrifugal force is placing the majority of the load on the outside wheels. So one could argue that the inside drive wheel isn’t doing much anyways. Also, if the inside wheel starts to slip, you loose driving force on the outside. A one-way would avoid that problem. I guess the biggest question is how it would affect the stability of the car while cornering. I bet anything the car manufacturers have tried this because it simplifies the car’s design if it works. Why not send an email to Associated and Losi asking them if it’s been tried? They might have some good information.
Posted on: 4/11/2005 11:08 AM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2865267

RE: Team B4 With A Reedy 19T
Don’t you have the manual? Get it from Associated here: http://www.teamassociated.com/shusting/CatalogHub/cathub_offroad.htm The B4 manual says to use a 22T pinion on Spec 19 motors with the 81T spur. From the recommended size, you can add 1 tooth for more speed or subtract 1 tooth for more acceleration. If you add 2 or more teeth then you risk burning out the motor. Also, you probably won’t go any faster because motors are limited by the torque they can ultimately supply. A motor has its limit...and no amount of teeth can overcome that. Associated says that the top speed of the B4 will be from mid-20 to mid-30 mph. A Spec motor is on the slower end, so I’m guessing that you’re probably looking at the high 20s. If speed is your only concern then get something like a 10 turn modified motor and add 1 tooth to the recommended pinion, which would be 19 +1 = 20. That would be fast. Your acceleration would be so so, but you’d be fast. If you add 2 teeth then you’d be getting into that area where you’re not going any faster...you’re just creating more heat.
Posted on: 4/9/2005 4:21 AM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2858940

RE: Mystery Solved! How to select the proper gearing for your electric RC!
[quote]Yours requires a knowledge of the target final drive ratio[/quote] Take another look. All that is required is knowing the current spur and pinion, and the diameters of the old and new tires.
Posted on: 4/8/2005 6:15 PM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2857606

RE: Mystery Solved! How to select the proper gearing for your electric RC!
[quote]Actually, Graystar, your STOCK B3 tires ( Proline M2 Holeshot p/n 6825) are only 3.20" in diameter. That is a circumference of 10.053"[/quote] Yeah, one would think that from looking at the specs…wouldn’t one? Except that the car actually came with the tires that are pictured on the manual...Bowties. And Bowties have a diameter of 3.5â€�, which gives a circumference of 11â
Posted on: 4/8/2005 2:20 PM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2856964

RE: Mystery Solved! How to select the proper gearing for your electric RC!
[quote]Look at EVERY recommended setup. If you will pay close attention, you will see that the Final Drive Ratio for MOST manufacturer is selected based on the circumference of the stock tire.[/quote] Like I said before, that only seems to work for stadium trucks. The circumference of my stock B3 tires is 11 inches but my FDR is 8.83 [quote]They outfit their trucks and buggies with such poor performing motors, that they deliberately overgear the chassis, to compensate for the lack of performcance.[/quote] Oh so they intentionally risk burning out their customers electronics?? I don't think so. They use that gearing because that’s the gearing required for those motors. Stock motors are always geared higher than modified motors. [quote]So, by your own formula, You proved me right.[/quote] No, it only proves what I said before...this it only seems to work for stadium trucks. If I were to put those tires on my B3 then the FDR wouldn’t match. In fact I just found Novak recommended gearing for the T4 when using an SS4300. Using their recommended gearing as a basis, I would go with a 13T pinion.
Posted on: 4/8/2005 9:11 AM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2856060

RE: Mystery Solved! How to select the proper gearing for your electric RC!
[quote]with the assinine method of using the same number of teeth as the motor has turns, and then trying again when I couldn't find a 12t pinion for my 12t motor.[/quote] OMG! Who told you to do that?? That IS asinine! On any modern racing truck or buggy there's only a 5-6 tooth range between a stock motor and a 10 turn motor. How many motors could a person burn out trying to find the right pinion?? It shouldn't take more than 4!! (actually, it shouldn't take any because you should start with a small pinion and work your way up.) Doesn't your car manual have any gearing recommendations? If it does, did you try them? If it doesn't, how far away are you now from the stock pinion?
Posted on: 4/8/2005 8:35 AM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2855978

RE: Mystery Solved! How to select the proper gearing for your electric RC!
[quote]Manufacturer recommended final drive ratio's are based on 1 really BIG assumption. They assume that You are NOT going to change your spur gear or the size of your tires.[/quote] That’s all they *can* assume. [quote]With all of the aftermarket parts available, the variables are incalculable.[/quote] I think I just demonstrated that it’s pretty easy to calculate. [quote]Manufacturer recommendation says that you need to maintain an 12.30:1 final drive ratio ( Novak SS). Well, if I'm running Road hawg 1 tires ( 9.425" circumference) on my T4,...[/quote] Novak is making the same assumptions that the manufacturers are making with regards to gearing. They even say…[quote] We are currently working with the vehicle manufacturers to offer a Gearing Chart that will be more specific.[/quote] Their gearing ratios are base on manufacturers’ specs. Of course they’re going to be off when you install odd sized tires! [quote]As for the Stampede and Rustler and Evader, I mis Typed. They are OVERGEARED to compensate for their rather pathetic motors.[/quote] This is where you are wrong, and why I question the premise of your entire system. The gearing is appropriate for the type of motor typically used in those vehicles. And THAT is the point that I’m making. Different motors require different gearing. There is no “one fits all� gear. If you follow my formula you can properly scale the manufacturers’ recommended gearing for any motor to any size tire. With your method you’re making a gearing presumption that may or may not be correct. I think that in most cases your method under-gears the car. [quote]You cannot deny results![/quote] The only results I see so far is that you solved overheating problems by under-gearing. When your gearing systems starts winning races, then I’ll believe. Until then I’ll use my simple formula.
Posted on: 4/8/2005 1:50 AM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2855577

RE: Mystery Solved! How to select the proper gearing for your electric RC!
[quote]I've got an Idea. Take a T4. with an 85t spur. Take off the stock M3 Hole shot tires. Put on, say some masher 2000's. You are running a Novak SS 4300 motor. What pinion will you use? Hmm? Nothing in this list is stock. What pinion do you use, wise guy? Come on, I want an answer, and an explaination of why......... [/quote] No prob... I would increase the spur/pinion ratio by the increase in tire size. from the tire specs... M3 diameter = 3.75" 2000 diameter = 4.9" Increase in tire diameter = 4.9/3.75 = 1.3067 or 30.67% From Novak specs: "the SS4300 Brushless Motor provides performance similar to a 27-turn racing stock brushed motor." So, from the T4 manual...stock motor = 87T spur/19T pinion ratio = 87/19 = 4.5789 just multiply by the increase... 4.5789 x 1.3067 = 5.98324863 That's my new spur/pinion ratio Finally, I divide 85 by 5.98324863 and get a pinion size of 14. The formula is: [Actual Spur] / (( [new tire dia.] / [stock tire dia.]) X ([sugg. spur] / [sugg. pinion])) = actual pinion needed
Posted on: 4/8/2005 1:25 AM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2855393

RE: Mystery Solved! How to select the proper gearing for your electric RC!
[quote]Look, It is NOT the final answer. Nobody ever said it was.[/quote] Hmmm...that’s not what the word “ideal� suggests... [quote]The DIAMETER of the pinion selected will determine it's output RPM.[/quote] If the diameter of the pinion is so important, then why isn’t it accounted for in the formula? Before relating the ratio to the tire circumference, the only thing you’ve worked with are tooth counts. The size of the pinion means nothing. It is the relationship of the tooth counts that matters. [quote]The Stampede/Rustler/Evader are deliberately UNDERGEARRED to compensate for ANEMIC motors.[/quote] Look again. The recommend ratios for the Stampede are *lower* than what you recommend. Tire is 14.92�, ratio is 12.69...using your formula, that’s a *positive* 2.23! That is, you get more than 1 inch of forward movement per revolution of the motor. Traxxas expects this level of car to be used with stock or mild motors, and that level of gearing is appropriate for those types of motor. [quote]I'm a 30 year old mechanical designer and the intricacies of this theory escape my mind too[/quote] That’s because there are no intricacies. The formula gets you somewhere near the manufacturer’s recommendations. Just save yourself a step and check the manufacturer’s recommendations! [quote]I have used it for a month now and i can say i now get the most out of motors and not have them dump in 4 minutes.[/quote] For buggies the formula under-gears the car. If you’re running a modified 10 turn motor then you’re probably right at Losi’s recommendation. Otherwise, you’re probably under-geared. That would explain your temps and longer runtimes. If you haven’t noticed a difference in top speed, then you were probably over-geared to begin with. Get out the manual and compare your current and past gearing with Losi’s recommendations. [quote]If you have a better Idea, let's hear it. [/quote] Follow the manufacturer's recommended gearing. They know more about their car than anyone.
Posted on: 4/7/2005 10:42 PM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2855109

RE: Mystery Solved! How to select the proper gearing for your electric RC!
[quote]The Ideal ratio is for the motor to turn X number of revolutions to move the tire 1 complete revolution. Whereas X is the diameter of the tire, in inches.[/quote] That’s *a* ratio...not the ideal ratio. Even Novak describes the 12.30 ratio they list as a “starting point�...not some ideal to reach for. The Associated T4 manual lists FDRs in the range of 11.31 to 12.57, depending on the motor...not on what tire you’re using. Obviously, Associated doesn’t share your “ideal� ratio theory. [quote]So your observation is correct. The motor will THEORETICALLY move the truck/buggy/car 1" for every revolution of the motor. But Why 1 revolution to 1 inch? The answer lies in the pinion's diameter. If you measure the diameter of your pinion gear, and multiply it by Pi, surprise! It has a cirumference of nearly 1". So, every revolution of your motor, the pinion travels more or less 1". It only makes sense to carry over that ratio to the tires[/quote]. If you used 32 pitch gears with the same number of teeth on the pinion and spur, the car would move the same distance per motor revolution even though the pinion is bigger. It has nothing to do with the size of the pinion…it has to do with the gear ratio only. [quote]As for heavier trucks, such as the E-Maxx, I've already addressed that.[/quote] But the E-Maxx has two motors. Obviously something is off if you need twice the power to maintain that “1 to 1� ratio. If you try it on a Stampede you’ll see that the stock gearing ratio is 12.69 while the tire diameter is nearly 15 inches (14.92) There are ratios in the 15 range on Traxxas’s chart, but they seem to be outside the range of normal. [quote]Ideally, the motor should turn 1 revolution for every inch of travel.[/quote] I don’t think there’s anything ideal about it. It’s just another ratio. By following your rule, you’ll simply stay within the range of the manufacturers’ recommended gearing...which is what you should have done in the first place! But if you try to keep a single gearing and apply it to all different motors, you may still end up burning out a few motors.
Posted on: 4/7/2005 9:14 PM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2854785

RE: Mystery Solved! How to select the proper gearing for your electric RC!
[quote]The theory is, it works.[/quote] But the question is...works for what? I think it only works for stadium trucks. [quote]It is easily converted between measurement systems. Take your tire O.D. in MM, and divide by 25.4.. That gives you the O.D. in inches. If that is news to you, then you have no right to question the rest of Skrap's formula [/quote] You don’t understand what I’m talking about. In physics, equations can always be converted to other forms when there are direct relationships. For example, there are direct relationships between voltage, current, and resistance. Therefore you can express one using the other two. You can say 10 volts or you can say 5 amps divided by .5 ohms...it’s the same thing. As long as there are real relationships, the equations can be restated. In this particular formula, the equation cannot be restated in other terms. At least, not the way it’s given. What this formula essentially says is that the car should travel 1 inch for every revolution of the motor. NOW it can be restated as 25.4 mm of travel per revolution, because now we have a relationship. My initial query remains, however. Why exactly is the 1 rev:1 inch relationship ideal? Seeing that SkrapIron was referring to blown ESC, melted motors, and other such heat related issues, the primary goal behind the relationship would seem to be limit rolling mass vs. power consumption. A single revolution of the motor represents a certain amount of energy that is available to perform work. SkrapIron has figured out that moving a stadium truck 1 inch forward is about all you would want out of 1 revolution’s worth of energy. If you try to get more work out of that 1 revolution, you overheat the system. This is, in fact, true for stadium trucks, but not heavier trucks. Owners of larger trucks may over-gear their cars and cause damage.
Posted on: 4/7/2005 5:34 PM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2853959

RE: Mystery Solved! How to select the proper gearing for your electric RC!
I must be missing something, but this all sounds like pseudo-science to me. First question is – what is the rational behind the 1-to-1 ratio? This statement was made in the original post: [quote]What size spur gear should I run? Well……. When selecting the spur gear size, you need to keep in mind that the ratio between the tire circumference and the final drive ratio should be 1 to 1.[/quote] And it seems to have been accepted as fact throughout the discussion. But why exactly should this be? I also find it very hard to accept any “formula� that can’t be converted between systems of measurement. It seems like this systems only works for Imperial measure and nothing else. [quote]Now the magic part.[/quote] Magic is right! You’re subtracting a ratio from a distance measurement! I’d just like to know the theory behind it all.
Posted on: 4/7/2005 1:47 PM by Author "Graystar" in the forum "RC Electric Off-Road Trucks, Buggies, Truggies and more"
http://www.rcuniverse.com/forum/fb.asp?m=2853341

RE: Hitec servo question
In general, steering doesn’t require a lot of torque. A 50 oz servo is good enough. Servo speed makes a much bigger difference. The faster the servo, the faster the steering response. The difference between a 0.2 sec servo and a 0.1 sec servo is noticeable when racing. The car reacts quicker. But if you’re not racing then it doesn’t really matter much.
Posted on: 1/30/2005 8:42 PM by Author "Graystar" in the forum "RC Car Radio Equipment"
http://www.rcuniverse.com/forum/fb.asp?m=2602966

RE: Converting pistol grip car radio for PC?
As far as I know, the RealRace G2 controller is the same as the original RR controller, and requires some modification to work with Virtual RC. However, a couple of people on the Virtual RC forum said they didn’t have to do anything to their RR controller. You just have to try it and see. If you want to race with other people then Virtual RC is the only game in town. RealRace seems to have been abandoned. The RR forums are dead, an the RR server never has any races. It’s a shame because RR does off-road racing, whereas Virtual RC doesn’t.
Posted on: 12/28/2004 7:21 PM by Author "Graystar" in the forum "RC Car Radio Equipment"
http://www.rcuniverse.com/forum/fb.asp?m=2477395