Project: Team Associated TC9
12-19-2011, 02:31 PM
#77
If anyone knows wither or not Losi belts (Jrx-s ,xxx-s,or xxx-4) are S3M that would be great!
The associated belts have a 3mm pitch..which is the same as pretty much all the other belts from other companies.. but they use STD (Super Torque Drive) tooth profiles.
wtcc your car looks great! Keep it up. I bet if you were to make a thread on it people would be very interested in it.
Thanks for the tips on the belt. I'm hoping the Team Losi belt I ordered is S3M and the right length.
Ouch, you did take quiet the hit on those out drives but they look awesome.
I agree touring cars with the motor mounted in the traditional matter are very well balanced... the this is.. the motor is the second heaviest component on the car. Having it so far from the center line..makes little sense to me.
Cars with an electronics layout such as the Xray T1 007's are well designed but like as you said many don't like them because they feel like the layshaft is too high. Also..when comparing the position of the saddle batteries to the position of a centralized battery the saddle packs are quiet far out on the chassis.
I understand what your saying with the energy loss of a single belt design..unfortunately, I don't have anyway of calculating that. I do know that the every pulley adds friction and rotating mass to the system.
The TC6 belts I have say that they are S3M and not 3mr. I presume a 3mr belt would work.. but I looked at their catalog and they only have 6mm wide belts?
After looking at the Schumacher Mission I notice it uses two belts. One from the layshaft to the rear diff pulley and one from the rear diff pulley to the front diff pulley. With how I centered the motor this certainly is an option if the one-belt system proves to not be the best...but I plan on only using one belt..and only added a second diff pulley to center the belt... my reason for centering the belt will be reveiled later.
I'm happy to hear that you haven't noticed performance issues with mixing tooth profiles. I'm still hoping the Team Losi uses STD profiles on their belts though. I tried looking thru many pictures of the Jrx-s, and xxx-s belts to see if I could see any markings indicating they use S3M.. unfortunately, none of the markings I could see showed this information.. so I suppose I will just have to wait for my belt to come.
I agree with you that it is unwise to cripple certain design aspects of the car for efficiency/centralized motor and battery. The Jrx-s for example...it is a great car.. but the engineers had to mount the a-arms very far out on the chassis thus, shortening the a-arms to accommodate the centralized motor and battery.
With the one-belt design I'm working with..I think the only things I will have to compromise are the rear chassis flex (should be an easy fix), a slightly higher lay-shaft (allows for larger spur gears though) , and run-time (Would only be a factor with modified motors and I will only be using 17.5). All of that will become clearer as I share my progress with everyone.
Chris, I think that your computer is just messing with you because the pictures are showing up great for me.
What is the difference in pitch? They use S3M pitch. There are different sources for these belts in different length. For my TC6 based project I use one DS3M belt. These are much harder to get, but not impossible. Only thing is the price: I paid 50€ for three in 3mm width. They also cut them in the wide I wanted:
Eds24, just search a little and there is a very good chance that you get what you need. Just be sure about the belt length
By the way: Nice idea with the diff! Very clever and much cheaper than my version = 220€ (this was a special price, official it is around 400 - 600€):
Keep coming with clever solutions, but be aware of the costs as they sum up fast!
Eds24, just search a little and there is a very good chance that you get what you need. Just be sure about the belt length
By the way: Nice idea with the diff! Very clever and much cheaper than my version = 220€ (this was a special price, official it is around 400 - 600€):
Keep coming with clever solutions, but be aware of the costs as they sum up fast!
Thanks for the tips on the belt. I'm hoping the Team Losi belt I ordered is S3M and the right length.
Ouch, you did take quiet the hit on those out drives but they look awesome.
I have two Kawada Sigma 2 cars (one V1 and one V1.1) and can assure everybody there is no problem with the motor being where it is. The car can be perfectly balanced the way it is. I have contemplated myself at length various options of centralising the motor on it, but never found the perfect/ideal solution. One thing is for sure, you need to redesign the bottom chassis at least, hence my idea of going back to the 007 which already has the symmetrical layout inbuilt in the design.
One other comment re the comparison with the Kyosho car, the Sigma2 is a very modern car with all the adjustments you find on offerings from all other top shelf companies and quality to match.
A single belt centralised design is possible along the lines of the old cars, but I think the best layout to start with is still that of the old Xray T1 007 models and using saddlepacks. The CG height problem I think is just academic.
And one last comment about efficiency of one belt vs two/three belt. I think you need to actually calculate the energy loss before you can conclude your design is more efficient. It may look that inherently is more efficient, but I don't think it's so clear cut when you factor in the losses incurred in having to route the belt around the motor. The Kyosho model mentioned above is an ingenious solution, but it lends itself more readily to moulded rather than CF chassies.
One other comment re the comparison with the Kyosho car, the Sigma2 is a very modern car with all the adjustments you find on offerings from all other top shelf companies and quality to match.
A single belt centralised design is possible along the lines of the old cars, but I think the best layout to start with is still that of the old Xray T1 007 models and using saddlepacks. The CG height problem I think is just academic.
And one last comment about efficiency of one belt vs two/three belt. I think you need to actually calculate the energy loss before you can conclude your design is more efficient. It may look that inherently is more efficient, but I don't think it's so clear cut when you factor in the losses incurred in having to route the belt around the motor. The Kyosho model mentioned above is an ingenious solution, but it lends itself more readily to moulded rather than CF chassies.
Cars with an electronics layout such as the Xray T1 007's are well designed but like as you said many don't like them because they feel like the layshaft is too high. Also..when comparing the position of the saddle batteries to the position of a centralized battery the saddle packs are quiet far out on the chassis.
I understand what your saying with the energy loss of a single belt design..unfortunately, I don't have anyway of calculating that. I do know that the every pulley adds friction and rotating mass to the system.
very nice. unless i'm misreading your intention, it appears you've taken a liking to the schumacher mission tranny layout as well.
for what it's worth, efficiency related to belt tooth mesh isn't really worth prioritizing in my opinion. having run multiple pulleys/belts over the years (in stock no less) i have never noticed any negative result to mixing/matching profiles (within reason). the worst mesh i had was experienced when using a fennerdrives (fht-3 profile) belt on a tamiya pulley (htd profile, i believe). it even wore the pulley teeth down some, but never was there any perceived loss of power on the track whether going by sight or by lap times. it may be measureable on an instrument, but it's just unimportant in terms of getting the car around the track quickly. i'm not looking for an argument, but to point out that crippling another element of the functionality simply for drive efficiency could be regrettable.
wtcc - pure sex right there.
for what it's worth, efficiency related to belt tooth mesh isn't really worth prioritizing in my opinion. having run multiple pulleys/belts over the years (in stock no less) i have never noticed any negative result to mixing/matching profiles (within reason). the worst mesh i had was experienced when using a fennerdrives (fht-3 profile) belt on a tamiya pulley (htd profile, i believe). it even wore the pulley teeth down some, but never was there any perceived loss of power on the track whether going by sight or by lap times. it may be measureable on an instrument, but it's just unimportant in terms of getting the car around the track quickly. i'm not looking for an argument, but to point out that crippling another element of the functionality simply for drive efficiency could be regrettable.
eg - corally once fantasized about how great the effects of a direct drive tranmission would be (see the 'assassin'), but shortly after its release all the team drivers were using the twin belt conversion because the car handled tons better w/o the motor sitting on the left rear tire. similarly, it was thought that the tc3 revolutionized lap times because of the shaft drive tranny. only later (after failed attempts by other mfrs and a failed revision) did most realize that the car had very good suspension geometry, weight bias, and flex characteristics.
keep up the good work and enjoy the holidays. wtcc - pure sex right there.
I'm happy to hear that you haven't noticed performance issues with mixing tooth profiles. I'm still hoping the Team Losi uses STD profiles on their belts though. I tried looking thru many pictures of the Jrx-s, and xxx-s belts to see if I could see any markings indicating they use S3M.. unfortunately, none of the markings I could see showed this information.. so I suppose I will just have to wait for my belt to come.
I agree with you that it is unwise to cripple certain design aspects of the car for efficiency/centralized motor and battery. The Jrx-s for example...it is a great car.. but the engineers had to mount the a-arms very far out on the chassis thus, shortening the a-arms to accommodate the centralized motor and battery.
With the one-belt design I'm working with..I think the only things I will have to compromise are the rear chassis flex (should be an easy fix), a slightly higher lay-shaft (allows for larger spur gears though) , and run-time (Would only be a factor with modified motors and I will only be using 17.5). All of that will become clearer as I share my progress with everyone.
Chris, I think that your computer is just messing with you because the pictures are showing up great for me.
Last edited by eds24; 12-19-2011 at 07:21 PM.
12-19-2011, 03:36 PM
#78
*nice thread*
I just would like to say that I am enjoying this thread, the ideas and thoughts of making these custom cars is really nice. I have a old jrx-s that I have customized to use the jrxs-r belts, (rear and front) and moved the motor to the rear of the car. It still handles just the same, maybe a little better to me. 
keep up the good work.
keep up the good work.
12-20-2011, 07:57 AM
#79
Finding out the belt size you need is easy, mock everything up then use a piece of string around the pulleys, pull it tight, mark it, measure the length and divide by 3
I would recommend the Schumacher Mi1/2 diff and pulleys, smoothest and longest lasting diff I've ever built but more importantly the single pulleys are sided so you can offset it and move the pulley closer to the middle. Or use the rear double with pulley and with some belt guides on the pulley and your sorted.
I have to mention the other inline car everyone has forgotten, the Tigermoth. I picked one up a few months ago but haven't had the chance to finish the rebuild yet.
12-20-2011, 08:05 PM
#80
I just would like to say that I am enjoying this thread, the ideas and thoughts of making these custom cars is really nice. I have a old jrx-s that I have customized to use the jrxs-r belts, (rear and front) and moved the motor to the rear of the car. It still handles just the same, maybe a little better to me. keep up the good work.
keep up the good work.That is the conclusion Jason from BMI came to when they made their first WGT car, they had a 1S lipo sitting ahead of the esc and motor to make their square.
Finding out the belt size you need is easy, mock everything up then use a piece of string around the pulleys, pull it tight, mark it, measure the length and divide by 3
I would recommend the Schumacher Mi1/2 diff and pulleys, smoothest and longest lasting diff I've ever built but more importantly the single pulleys are sided so you can offset it and move the pulley closer to the middle. Or use the rear double with pulley and with some belt guides on the pulley and your sorted.
I have to mention the other inline car everyone has forgotten, the Tigermoth. I picked one up a few months ago but haven't had the chance to finish the rebuild yet.
Finding out the belt size you need is easy, mock everything up then use a piece of string around the pulleys, pull it tight, mark it, measure the length and divide by 3
I would recommend the Schumacher Mi1/2 diff and pulleys, smoothest and longest lasting diff I've ever built but more importantly the single pulleys are sided so you can offset it and move the pulley closer to the middle. Or use the rear double with pulley and with some belt guides on the pulley and your sorted.
I have to mention the other inline car everyone has forgotten, the Tigermoth. I picked one up a few months ago but haven't had the chance to finish the rebuild yet.
I looked into Schumacher Mi1/2 diffs and the outdrives are the right diameter..but I'm not sure the outdrives would be long enough or two long..or if they would work with the Associated CVA's. I think I might need 40t diff pulley like on the TC6 compared to 36t on the Schumacher in order for the belt to go above and below the motor. That's a good idea though!
Oh yea the Tigermoth is an awesome design! I wish it wasn't so expensive..or discontinued now..and if I wasn't planning on trying to get a job at Team Associated in a few years I would probably be driving one of those.
12-21-2011, 05:43 AM
#81
Tech Fanatic
iTrader: (1)
Hi!
Kev, I wonder how long belt last?
How many tooths will be connected? 2-3?
I look to your car, again and again and only one weak point is in my head.
pinion + belt ...
I wish you good luck in this place
I have hope that this place will last long time.
And suspension, crazy
Kev, I wonder how long belt last?
How many tooths will be connected? 2-3?
I look to your car, again and again and only one weak point is in my head.
pinion + belt ...
I wish you good luck in this place
I have hope that this place will last long time.
And suspension, crazy
12-21-2011, 06:54 AM
#82
I agree touring cars with the motor mounted in the traditional matter are very well balanced... the this is.. the motor is the second heaviest component on the car. Having it so far from the center line..makes little sense to me.
Cars with an electronics layout such as the Xray T1 007's are well designed but like as you said many don't like them because they feel like the layshaft is too high. Also..when comparing the position of the saddle batteries to the position of a centralized battery the saddle packs are quiet far out on the chassis.
I understand what your saying with the energy loss of a single belt design..unfortunately, I don't have anyway of calculating that. I do know that the every pulley adds friction and rotating mass to the system.
It can be worked out very easily what the efficiency losses are. The main inherent problem a single belt design has is the convoluted routing of the belt to make sure there is enough grip on it so it doesn't jump off the layshaft pulley.
On the Kawada cars, the belt literally does an about turn (180 degrees). That means the traction force applied by the belt to the pulley is pulling the pulley to one side. There is also an idler which has the belt wrapped around it again at 180 degrees. Again, the idler shaft is effectively taking the entire stress put in the belt. These two factors are reducing the efficiency a fair bit and you only need high school physics to work out by how much. Imagine you wrap a piece of string around a pole and pull on both ends. That's what that belt is doing.
Now in your design the belt doesn't wrap around the pulley 180degrees, but still more than it does in a normal two belt layout. That is where you need to work out what the efficiency is and compare with other designs. My hint here is that efficiency will end up being a function of the angle of wrapping around the pulley.
Another way to make sure the belt doesn't skip on the drive pulley I thought of is to have one roller that presses the belt firmly in the dirve pulley teeth as the belt goes past the drive pulley (or versions of this idea, including two pulleys that just tension the belt down on the drive pulley with the associated pitfalls). All these ideas introduce losses that need to be worked out before a decision is made as to which is the most efficient.
My personal feeling is that you get some and you give some and in the end the benefit is minor, but it might create advantages elsewhere (as in allow a more centralised distribution of components for instance, if this is of major importance to you).
Anyway, an interesting exercise that has eaten many of my nights away.
12-21-2011, 08:22 AM
#83
Another way to make sure the belt doesn't skip on the drive pulley I thought of is to have one roller that presses the belt firmly in the dirve pulley teeth as the belt goes past the drive pulley (or versions of this idea, including two pulleys that just tension the belt down on the drive pulley with the associated pitfalls). All these ideas introduce losses that need to be worked out before a decision is made as to which is the most efficient.
If you need any dimensions for the Schumacher diffs, just ask
As I said I haven't run the tigermoth yet (picked it up relatively cheap on here) but it does appear to have more weight in the back but given the layout of the car, making it mid motor with one half of a saddle pack either side should be a piece of piss to do and would offer a very compact heavy square in the middle of the car.
12-22-2011, 10:19 PM
#84
Today I was able to start modifying the chassis for the bottom half of the belt to pass under the motor.. I think I'm going to have to lengthen the slot about 7-10mm but its been too long without any pictures for you guys I also have to sand it.. to make it a tiny bit wider and nice and smooth and straight...you can get the idea though.. the bottom half of the belt will pass under the motor..and then come back up on top of the chassis via a belt guide to go under the battery. The top half of the belt will go through the pulley and an idler..and then over the top of motor and all the way to the front diff. One of the issues of having a large slot out of the middle of the chassis is the increased level of chassis flex.. I think that this can be resolved by either a stiffer upper chassis in the rear.. and/or connecting the lay shaft uprights together with an aluminum rod.
Now before you guys comment about how I'm going to have to raise the battery up too far for the belt to go under it thus, raising the COG terribly high.. just hang in there.. and I will show you how I plan for the belt to be on top of the chassis..and for the height of the battery to be the same.. or lower than the current cars.
Tomorrow the parts to complete the front slipper spool will be here so I will get that done. I will also have the pulley for the layshaft..so I can raise the layshaft to the correct height and get it mounted. Because of the Holidays.. not sure when my Losi xxx-4 belt/idler will get here.
For the manufacturers.. they want to make money..whatever makes them money.. they make..even if it means sacrificing performance. The two-belt system and layout found on the Tc5's, Tc6's, xrays, photons, etc is proven..and it is simple, thus it makes them money. I agree that this proven layout is excellent.. but it was designed with nimh batteries in mind and adapted for lipo batteries..and not only do we have lipo batteries now..but we now have short batteries. I would say I do think the current proven layouts are the best for full size nimh/lipo packs as even a layout like the JRX-S or E4 doesn't seem like it would increase performance substantially while sacrificing suspension geometry or efficiency.
BUT, like I have said.. the new "shorty" battery packs open up many doors for the progression of the design of these cars which I do believe can have better..more centralized weight distrubtion. So many opportunities have been opened that even ROAR has acknowledged it..and is trying to stop the innovation.
Hmmm... my high school physics class must of sucked.. as that wasn't a concept that we covered haha if we did.. I must have forgotten how. Unfortunately, I'm not sure how to complete those calculations. Perhaps after I take a few more physics classes... right now I'm going off of what other opinions of the real world performance of each...
My understanding from what I have read is people comment that one-belt is best for Modified motors on asphalt or stock on asphalt... while two belts is better for stock racing on high traction surfaces. I'm looking at perhaps designing this option into my car.. the ability to switch between one-belt and two-belts..depending on what class is being run.
Thank you for the recomendation on the drive pulley set-ups.. unfortunately, to my knowledge I have to use a certain design in order to get the top of the belt to clear the top of the motor while not raising the height of the lay shaft too high.
I agree.. with r/c car designing.. you have to give and take.. I think I will be able to take the one belt or two belt option..and gain centralized motor and battery at the expense of run-time.
Thanks! I've tried to figure out how I could use the Schumacher diffs.. but I think they simple just aren't big enough it diameter. I'll certainly let you know if I need some measurements though.
Good luck with the Tigermoth.. I agree it shouldn't be too difficult to move the motor to the middle of the car and do the saddle layout you had described.
Now before you guys comment about how I'm going to have to raise the battery up too far for the belt to go under it thus, raising the COG terribly high.. just hang in there.. and I will show you how I plan for the belt to be on top of the chassis..and for the height of the battery to be the same.. or lower than the current cars.
Tomorrow the parts to complete the front slipper spool will be here so I will get that done. I will also have the pulley for the layshaft..so I can raise the layshaft to the correct height and get it mounted. Because of the Holidays.. not sure when my Losi xxx-4 belt/idler will get here.
Well, it seems to make sense to all the manufacturers who make a living out of what you are trying to do as a hobby. I would like to see the perfect car too, but I am afraid it's not possible the way we see perfection. Perhaps then we should just change our view of perfection.
It can be worked out very easily what the efficiency losses are. The main inherent problem a single belt design has is the convoluted routing of the belt to make sure there is enough grip on it so it doesn't jump off the layshaft pulley.
On the Kawada cars, the belt literally does an about turn (180 degrees). That means the traction force applied by the belt to the pulley is pulling the pulley to one side. There is also an idler which has the belt wrapped around it again at 180 degrees. Again, the idler shaft is effectively taking the entire stress put in the belt. These two factors are reducing the efficiency a fair bit and you only need high school physics to work out by how much. Imagine you wrap a piece of string around a pole and pull on both ends. That's what that belt is doing.
Now in your design the belt doesn't wrap around the pulley 180degrees, but still more than it does in a normal two belt layout. That is where you need to work out what the efficiency is and compare with other designs. My hint here is that efficiency will end up being a function of the angle of wrapping around the pulley.
Another way to make sure the belt doesn't skip on the drive pulley I thought of is to have one roller that presses the belt firmly in the dirve pulley teeth as the belt goes past the drive pulley (or versions of this idea, including two pulleys that just tension the belt down on the drive pulley with the associated pitfalls). All these ideas introduce losses that need to be worked out before a decision is made as to which is the most efficient.
My personal feeling is that you get some and you give some and in the end the benefit is minor, but it might create advantages elsewhere (as in allow a more centralised distribution of components for instance, if this is of major importance to you).
Anyway, an interesting exercise that has eaten many of my nights away.
It can be worked out very easily what the efficiency losses are. The main inherent problem a single belt design has is the convoluted routing of the belt to make sure there is enough grip on it so it doesn't jump off the layshaft pulley.
On the Kawada cars, the belt literally does an about turn (180 degrees). That means the traction force applied by the belt to the pulley is pulling the pulley to one side. There is also an idler which has the belt wrapped around it again at 180 degrees. Again, the idler shaft is effectively taking the entire stress put in the belt. These two factors are reducing the efficiency a fair bit and you only need high school physics to work out by how much. Imagine you wrap a piece of string around a pole and pull on both ends. That's what that belt is doing.
Now in your design the belt doesn't wrap around the pulley 180degrees, but still more than it does in a normal two belt layout. That is where you need to work out what the efficiency is and compare with other designs. My hint here is that efficiency will end up being a function of the angle of wrapping around the pulley.
Another way to make sure the belt doesn't skip on the drive pulley I thought of is to have one roller that presses the belt firmly in the dirve pulley teeth as the belt goes past the drive pulley (or versions of this idea, including two pulleys that just tension the belt down on the drive pulley with the associated pitfalls). All these ideas introduce losses that need to be worked out before a decision is made as to which is the most efficient.
My personal feeling is that you get some and you give some and in the end the benefit is minor, but it might create advantages elsewhere (as in allow a more centralised distribution of components for instance, if this is of major importance to you).
Anyway, an interesting exercise that has eaten many of my nights away.
BUT, like I have said.. the new "shorty" battery packs open up many doors for the progression of the design of these cars which I do believe can have better..more centralized weight distrubtion. So many opportunities have been opened that even ROAR has acknowledged it..and is trying to stop the innovation.
Hmmm... my high school physics class must of sucked.. as that wasn't a concept that we covered haha if we did.. I must have forgotten how. Unfortunately, I'm not sure how to complete those calculations. Perhaps after I take a few more physics classes... right now I'm going off of what other opinions of the real world performance of each...
My understanding from what I have read is people comment that one-belt is best for Modified motors on asphalt or stock on asphalt... while two belts is better for stock racing on high traction surfaces. I'm looking at perhaps designing this option into my car.. the ability to switch between one-belt and two-belts..depending on what class is being run.
Thank you for the recomendation on the drive pulley set-ups.. unfortunately, to my knowledge I have to use a certain design in order to get the top of the belt to clear the top of the motor while not raising the height of the lay shaft too high.
I agree.. with r/c car designing.. you have to give and take.. I think I will be able to take the one belt or two belt option..and gain centralized motor and battery at the expense of run-time.
Kind of similar to how big car manufacturers route the timing belts on engine's, the tensioner's are positioned to force the belt in to the pulley.
If you need any dimensions for the Schumacher diffs, just ask As I said I haven't run the tigermoth yet (picked it up relatively cheap on here) but it does appear to have more weight in the back but given the layout of the car, making it mid motor with one half of a saddle pack either side should be a piece of piss to do and would offer a very compact heavy square in the middle of the car.
If you need any dimensions for the Schumacher diffs, just ask
As I said I haven't run the tigermoth yet (picked it up relatively cheap on here) but it does appear to have more weight in the back but given the layout of the car, making it mid motor with one half of a saddle pack either side should be a piece of piss to do and would offer a very compact heavy square in the middle of the car.Good luck with the Tigermoth.. I agree it shouldn't be too difficult to move the motor to the middle of the car and do the saddle layout you had described.
12-23-2011, 01:32 AM
#85
Hi Eds, just wondering how much higher you have had to mount your motor to accomodate the belt underneath. A chassis is approx 2.5mm and a belt roughly the same - in order to give the belt enough room to tighten when in use it would have to sit at aorund 1.5 - 2mm above the chassis wouldn't it? Can you post a pic of the side view of the car when you have time?
Maybe i missed somewhere if you had found a solution to this - pullies are an option, but each one just saps alittle more efficency away from the drivetrain.
Again sorry if you have mentioned it before, but what class are you planning to race the car in?
Last point...have you checked out the Yokomo DRB before? It is a drift chassis so doesn't get too much press outside of Japan, but it has a very interesting belt layout - just another thing to look at and maybe gain some inspirtaion from
Good luck mate.
Chris
Maybe i missed somewhere if you had found a solution to this - pullies are an option, but each one just saps alittle more efficency away from the drivetrain.
Again sorry if you have mentioned it before, but what class are you planning to race the car in?
Last point...have you checked out the Yokomo DRB before? It is a drift chassis so doesn't get too much press outside of Japan, but it has a very interesting belt layout - just another thing to look at and maybe gain some inspirtaion from
Good luck mate.
Chris
12-23-2011, 06:30 AM
#86
awesome. i wouldn't worry about the flex. you can get a car to steer with a flexible rear end by changing any number of the 500 other variables on these things. and when you do, it may even be easier to drive ...
man, that's good stuff.
(looks as though you had a slight mishap along the way .. a little c/a and back at it?)
man, that's good stuff.
(looks as though you had a slight mishap along the way .. a little c/a and back at it?)
12-23-2011, 10:10 PM
#87
Some parts did arrive today.. unfortunately, I will have to wait till tuesday or wednesday for my xxx-4 belt.. I had ordered a black hd belt.. then I got an email saying they were all out and were cancelling my order.. so I had to pick up a yellow xxx-4 belt.. it will be quiet the interesting color combination.
I was able to build the front slipper spool today. I raised the layshaft mounts..bringing the layshaft up to 27.5mm compared to the TC6's 23mm. I also built an idler and figured out to mount it and for it to double as a belt tensioner like the xxx-s.
Tomorrow.. I hope to get the layshaft finished..and also mount and finish the idler. More pictures coming tomorrow.
Hey Chris
I have raised the motor 1mm above the chassis.. the belt is right at 2mm thick, while , as you know the chassis is 2.5mm thick. This gives me about 1.5mm of clearance. I think this should be enough..if not.. I don't think it would hurt terrible if the belt skimmed the bottom of the motor here or there..since it is smooth metal. Also, the design I have in mind for the belt guide to route the belt on top of the chassis should reduce the up and down movement of the belt.. this all will just have to be tested. In total the motor is 2mm higher than the motor on the TC6. I will post a side shot once I get a few more parts.
I don't believe I have mentioned it before.. but, I will be racing this car on carpet in 17.5 open and also 17.5 blinky (depending on which track I am at).
Hmm.. I havent seen that Yokomo.. I just checked out some pictures.. and I agree.. it does have a very interesting belt layout. Very intriguing way at lowering the layshaft.
Thanks seaball for the advice about the flex.. that puts me at ease about it..one less thing I have to worry about.
Thanks... and I promise.. it only gets better.. I'm just getting started..
Ah yes.. a bit of an accident.. I actually didn't cut myself with the saw.. cardboard surround my workshop and I got a cardboard cut.
I was able to build the front slipper spool today. I raised the layshaft mounts..bringing the layshaft up to 27.5mm compared to the TC6's 23mm. I also built an idler and figured out to mount it and for it to double as a belt tensioner like the xxx-s.
Tomorrow.. I hope to get the layshaft finished..and also mount and finish the idler. More pictures coming tomorrow.
Hi Eds, just wondering how much higher you have had to mount your motor to accomodate the belt underneath. A chassis is approx 2.5mm and a belt roughly the same - in order to give the belt enough room to tighten when in use it would have to sit at aorund 1.5 - 2mm above the chassis wouldn't it? Can you post a pic of the side view of the car when you have time?
Maybe i missed somewhere if you had found a solution to this - pullies are an option, but each one just saps alittle more efficency away from the drivetrain.
Again sorry if you have mentioned it before, but what class are you planning to race the car in?
Last point...have you checked out the Yokomo DRB before? It is a drift chassis so doesn't get too much press outside of Japan, but it has a very interesting belt layout - just another thing to look at and maybe gain some inspirtaion from
Good luck mate.
Chris
Maybe i missed somewhere if you had found a solution to this - pullies are an option, but each one just saps alittle more efficency away from the drivetrain.
Again sorry if you have mentioned it before, but what class are you planning to race the car in?
Last point...have you checked out the Yokomo DRB before? It is a drift chassis so doesn't get too much press outside of Japan, but it has a very interesting belt layout - just another thing to look at and maybe gain some inspirtaion from
Good luck mate.
Chris
I have raised the motor 1mm above the chassis.. the belt is right at 2mm thick, while , as you know the chassis is 2.5mm thick. This gives me about 1.5mm of clearance. I think this should be enough..if not.. I don't think it would hurt terrible if the belt skimmed the bottom of the motor here or there..since it is smooth metal. Also, the design I have in mind for the belt guide to route the belt on top of the chassis should reduce the up and down movement of the belt.. this all will just have to be tested. In total the motor is 2mm higher than the motor on the TC6. I will post a side shot once I get a few more parts.
I don't believe I have mentioned it before.. but, I will be racing this car on carpet in 17.5 open and also 17.5 blinky (depending on which track I am at).
Hmm.. I havent seen that Yokomo.. I just checked out some pictures.. and I agree.. it does have a very interesting belt layout. Very intriguing way at lowering the layshaft.
awesome. i wouldn't worry about the flex. you can get a car to steer with a flexible rear end by changing any number of the 500 other variables on these things. and when you do, it may even be easier to drive ...
man, that's good stuff.
(looks as though you had a slight mishap along the way .. a little c/a and back at it?)
man, that's good stuff.
(looks as though you had a slight mishap along the way .. a little c/a and back at it?)
Thanks... and I promise.. it only gets better.. I'm just getting started..
Ah yes.. a bit of an accident.. I actually didn't cut myself with the saw.. cardboard surround my workshop and I got a cardboard cut.
12-24-2011, 07:21 AM
#88
Tech Fanatic
If anyone knows wither or not Losi belts (Jrx-s ,xxx-s,or xxx-4) are S3M that would be great!
The associated belts have a 3mm pitch..which is the same as pretty much all the other belts from other companies.. but they use STD (Super Torque Drive) tooth profiles.
The TC6 belts I have say that they are S3M and not 3mr. I presume a 3mr belt would work.. but I looked at their catalog and they only have 6mm wide belts?
The associated belts have a 3mm pitch..which is the same as pretty much all the other belts from other companies.. but they use STD (Super Torque Drive) tooth profiles.
The TC6 belts I have say that they are S3M and not 3mr. I presume a 3mr belt would work.. but I looked at their catalog and they only have 6mm wide belts?
http://www.rctech.net/forum/electric...ious-cars.html
12-24-2011, 11:34 AM
#89
that drb car looks pretty sweet all told, shoud i dont know if you would want a belt system like that in a race car. looks like it would create a lot of drag.
very innovative just the same though. kinda makes me wonder if front motor TC could come back with the shorter batteries.
very innovative just the same though. kinda makes me wonder if front motor TC could come back with the shorter batteries.
12-24-2011, 04:54 PM
#90
Work continued on the TC9 today..
I was able to complete the idler system and get it mounted.. it also doubles as a belt tensioner.. I slot the chassis.. so that it can move back and forth. Many variables can also be changed on it as well.. such as the height and bearing sizes.
I had to trim down the side walls on the 4-tec 20t pulley so that the motor can slide back all the way. Once I had that finished I completed the lay shaft and mounted that. As you can see.. I still need to raise the layshaft up a couple more millimeters.. to allow for the belt to clear the motor.
I also started working on a upper deck design..the car will have the same exact steering geometry and bell crank as the stock TC6.. and no joke.. I will be using part of the upper TC6 chassis for my upper chassis.
Here is the car as it stands..
Next up.. its time to finish the rear of the car, finish the steering, order batteries, and design and build the upper chassis. I'm patiently waiting for the xxx-4 yellow belt..so I can see if it fits or not.. my guess is that it will be too long :/
Happy holidays to all!
Thanks.. I have looked at that thread many a time.. unfortunatly it doesn't include the xxx-s and also doesn't tell what tooth profile the belts have.
Yea I agree the belt system looks pretty inefficient. Idk.. I think with the short lipo's and a front mounted motor the weight bias would be way too far forward.. who knows though.
I was able to complete the idler system and get it mounted.. it also doubles as a belt tensioner.. I slot the chassis.. so that it can move back and forth. Many variables can also be changed on it as well.. such as the height and bearing sizes.
I had to trim down the side walls on the 4-tec 20t pulley so that the motor can slide back all the way. Once I had that finished I completed the lay shaft and mounted that. As you can see.. I still need to raise the layshaft up a couple more millimeters.. to allow for the belt to clear the motor.
I also started working on a upper deck design..the car will have the same exact steering geometry and bell crank as the stock TC6.. and no joke.. I will be using part of the upper TC6 chassis for my upper chassis.
Here is the car as it stands..
Next up.. its time to finish the rear of the car, finish the steering, order batteries, and design and build the upper chassis. I'm patiently waiting for the xxx-4 yellow belt..so I can see if it fits or not.. my guess is that it will be too long :/
Happy holidays to all!
that drb car looks pretty sweet all told, shoud i dont know if you would want a belt system like that in a race car. looks like it would create a lot of drag.
very innovative just the same though. kinda makes me wonder if front motor TC could come back with the shorter batteries.
very innovative just the same though. kinda makes me wonder if front motor TC could come back with the shorter batteries.
Last edited by eds24; 12-24-2011 at 07:47 PM.