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getting back into it after 45 years..need some advice

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  • getting back into it after 45 years..need some advice

    I have just returned to the hobby after a very long time. My local 1/32 club runs the "older" trans am class which is pre 72. It seems like the Scalextric is the brand with the most variety, but then the cars are heavily modified using Slot It parts. I can't even locate a picture of the Scalextric chassis in a 69-70 mustang, but I think they are changing out the motor "pod" to another brand. Is that possible? and if so, what is the common recommendation?
    Along these lines of conversation, I notice that the anglewinder motor configuration does not allow for any gear changes since the mounts appear fixed in the chassis, do you have to replace both the pinion and ring gear to make changes in order to make up the slack between the 2? or is there some other adjustment mechanism?
    Do any of the scalextric bodies interchange with other chassis?
    I've wondered through the shapeways website and find that it is about as confusing as trying to find specs on the Scalextric chassis, I'm sure those in the sport are familiar with it all, but it is a far cry from the brass chassied 1/32 and 1/24 cars that I grew up on.
    I think, for the most part, I've settled on the Slot It brand since a lot of cars use this chassis or parts from it, I've tested a few of these against other bands and they seem to work very well, but as with many, the body choices are limited.
    Any advise would be appreciated.

  • #2
    Black-sheep. we could suggest till we go blue in the face, and still get the answers wrong, because different clubs do things differently - both the rules and what works on those tracks.
    You need to be getting this particular advice From your club.
    If the guys are worth racing with, they will gladly open up their cars for you to take some photographs, explain what parts they use, and the rules they race under.
    Maybe they allow 3D chassis swap out so you can use say Slot.it mechanics with ease,
    maybe they don't and do a lot of engineering to cobble good quality parts into a Scalextric chassis.
    maybe they allow lightened interiors/glass etc, maybe they don't
    What tyres work on their surface, whether you are allowed to treat them - and with what,
    minimum track clearance.

    All stuff you are better getting from the people you race with.
    If they don't care to share that kind of help, - shake the dust off your feet as you leave the room.

    ps, My club don't allow chassis swap, but we engineer the heck out of replacing parts, moving the motor 1mm or the rear axle, so we can use 17.5/18mm spur gears, and we lower, we weight, we lighten interiors and use lexan replacements for the "glass", we fit 25k to 30k motors, we use wood guides and so on.
    For us, the easiest car to get set up is a 1970 - not 69, 1970 Camaro s is it a little wider - and lower when finished.

    Comment


    • #3
      I can't even locate a picture of the Scalextric chassis in a 69-70 mustang, but I think they are changing out the motor "pod" to another brand. Is that possible?
      I don't know about that, but you may find the answer in their Service Sheets. It could also be worth asking about Scalextric product in their forum, here.

      Along these lines of conversation, I notice that the anglewinder motor configuration does not allow for any gear changes since the mounts appear fixed in the chassis, do you have to replace both the pinion and ring gear to make changes in order to make up the slack between the 2? or is there some other adjustment mechanism?
      I think it's common for some manufacturers to provide pairs of pinion/spur gears that work together, but others here will be more expert. Why do you want to do an anglewinder setup? The only advantage (just my opinion) is the potential for magnetic motor downforce to the rails on a plastic or magnabraid track.

      I think, for the most part, I've settled on the Slot It brand since a lot of cars use this chassis or parts from it, I've tested a few of these against other bands and they seem to work very well, but as with many, the body choices are limited.
      For many slot racers, once you've experimented with Slot.it there's no looking back. And of course, their HRS/2 chassis is designed to accommodate a variety of other slot car bodies. Their range of replacement pods and gears and every other darn tune-up item to make things go quicker is remarkable.

      Comment


      • #4
        If you have gears that conform to standard pitches -- typically 48 pitch or 64 pitch -- there is a simple way to spec replacement gears. For every tooth you add to the pinion gear your subtract one from the spur gear, and vice-versa. The spacing motor-to-axle does not change.

        Sadly, some slotcar manufacturers use gears with oddball pitches. I think SlotIt, and maybe other manufacturers sell replacement gears in sets -- a pinion matched to the spur for their particular chassis. I even seem to remember that those matched gears are colored the same, to make them easier to keep matched. Use third-party gears at your own risk.

        Ed Bianchi

        Comment


        • #5
          SlotzNZ, that is a pretty good response, to my somewhat vague question, I am posting a set of rules below..

          WestCoastRacer, I will dig through those, thank you

          HOracepro, thank you, I will also look into that.

          pardon the coffee stains...the classes with an asterisk are the ones that I'm considering

          Comment


          • #6
            Coffee stains are always good stains - unless you spilled too much.

            Those rules makes it pretty easy.
            Do look at which models are already popular on track - they are likely the easiest to set up fast. Ask what brand of 3D chassis they use, Oilifer, Amato and JS Chassis design are all good brands.

            For TransAm, since it is pre-1970, you may want to opt for a Scalex Mustang or a '69 Camaro. I THINK that '69 Camaro is still slightly wider than the mustang. If you could fit narrow rims with a sidewinder pod, that would be my personal preference on wood for handling, if not, use an inline. I would be avoiding a short can angle-winder, I think with those narrow chassis, it will have twisting torque forces out of corners.
            Slot.it and others make a nice deep wood guide with about 8mm depth. CH07 is the Slot.it code.

            As for gears - here is my suggestion for the pre 70 transam

            The "rule" HoRacePro gave on changing pinions and spurs seems illogical, and changes final ratio radically, as you are taking the ratio one direction or the other with both gears at the same time.
            You will need to experiment on ratios, but for sidewinder, try to use 11 or 12 tooth 6.5mm pinions, as they are the two in the middle of the sliding pitch/modulus range from Slot.it - you will probably end up with a chassis which has a Slot.it pod. So their tooth contact point is closest to 0.5 modulus (which is roughly 50 pitch - as Slot.it no longer describe their gear in pitch, but in modulus)
            Mate those with a spur to start which gives roughly 2.7:1 gear ratio (eg 31 to 33 tooth spur) and small O.D. wheels/tyres. A 32 or 33 tooth spur is closest to 0.5 modulus on that side of things.
            That is a decent point to start gear ratio tuning with that low power motor on a mid to larger circuit.
            Handy chart - sorry, a bit out of date.


            Slot.it do not make pinion/gear sets at all, but they make complete rear ends as swap out on Scalextric/Carrrera etc
            But as you will be using pods, so buying individual gears, axles and pinions is probably the way to go, unless you start with kit KK13b with a 0.5mm offset sidewinder pod.
            Avoid buying a KK12b as it has a 1mm offset pod and with the small wheels you need on a Trans-Am, you will be short on ground clearance.
            If you can't shoehorn a sidewinder pod into a 3D chassis under your chosen body, you will need to buy individual parts as Slot.it don't make any inline style motor pods as kits.

            If budget allows, buy loose parts and use the 6.5mm Ergal pinions rather than brass, they are quieter and smoother. eg codes 6511E and 6512E

            For CanAm - just go buy a Thunderslot McLaren Elva and tune it.....

            Group 5 - Buy a Sideways, they come with a flat 6 angle-winder, check with your club, if they don't allow those, just swap to a Baby King or a Sideways Baby Raptor which has identical motor spec (if they allow that)
            My overall experience is the the BMW M1 is the easiest one to tune to the max, but I have seen clever builders get any of them good.
            The Capri-Mustang is very popular, but personally my least favourite for tuning. - Have built over a dozen Sideways Group 5 up for club racing.
            But most of mine I convert to Sidewinder, which you cannot do under your rules.
            Last edited by SlotsNZ; 02-14-2020, 12:42 PM.

            Comment


            • #7
              SlotsNZ, you missed my point. You may need a refresher on how a set of spur gears work.

              In a simple spur gear setup the pinion gear and the spur gear are spaced so their pitch diameters 'roll' against each other. If you keep the centerline spacing fixed, a decrease in the pitch diameter of one must be matched by an increase in the pitch diameter of the other.

              Now the relationship between the number of teeth on a gear and its pitch diameter is linear. Adding a tooth increases the pitch diameter by the tooth pitch divided by pi. Subtracting a tooth decreases the pitch diameter by the same amount. This is independent of the total number of teeth on the gear! It comes back to the definition of pi. That is the circumference of a circle is equal to pi times its diameter. A linear relationship.

              If you can get your head around the fact that this works for ANY size gear -- and it is a bit counterintuitive, I admit -- you can see how you can change ratios without changing the centerlines. Add or subtract a tooth from the pinion, you subtract or add a tooth to the spur. It works.

              And of course, if you add or subtract multiple teeth, it still works.

              My apologies if you are not up to speed with gear pitches and pitch diameters. That's understandable. It is a strange fact that you can earn a mechanical engineering degree without ever learning about them! But if you want to take a trip down the rabbit hole of gear theory and design the internet is your friend.

              It is a VERY deep rabbit hole!

              Ed Bianchi

              Comment


              • #8
                I would add to the above that Slot-It (and others I think) use a "trick" to keep the (approximate) pitch diameter constant while changing tooth number. The trick involves changing the tooth profile to move the contact point, hence the effective pitch diameter in or our as needed. The result is that some gear sets work well while others - those involving the greatest distortion - are rough and noisy. For this reason I prefer to use conventional fixed DP gearing - 48, 64, 72 or 80 DP. A caveat: As the DP increases, the gear size for a given number of teeth decreases, allowing higher tooth numbers for the same motor to axle spacing for sidewinders or more compact set-ups for inline motors. As a general rule, more teeth = smoother operation but, as the DP increases (and, correspondingly tooth size shrinks) the the clearance setting becomes more critical.

                EM

                Comment


                • #9
                  It looks like your rules are similar to those of Shoreline Model Raceways. Take a look at this: https://drive.google.com/file/d/0BzL...ew?usp=sharing
                  1/32nd slot cars do not use standard pitch sidewinder or anglewinder spur gears, tricks are played with the pitch diameter so that gears of the same diameter may have different tooth counts and still mesh well. Usually you would want to use pinion and spur gears by the same maker, but often gears by different makers will work well.

                  Comment


                  • #10
                    Hi Ed

                    No idea about gear pitch or diameters so I may be wrong but from what I read you are saying if I have 27t/9t combo (3:1) if I change to a 10t pinion I should then change to a 26t spur. This then changes the ratio to 2.6:1 If I go the other way and drop the pinion to an 8t then I go a 28t gear or 3.5:1 ratio - how does that work? On sidewinders with say the common 11t/33t (3:1) if I put a 12t pinion on then I drop to 32t gear (2.66:1) they seem quite a change in ratio and will therefore change the performance of the car.

                    Just trying to learn a bit more and understand the dark arts

                    Comment


                    • #11
                      Originally posted by dangermouse View Post
                      Just trying to learn a bit more and understand the dark arts
                      Nothing dark about it :-)!

                      If you are using Slot.it, NSR, or any other modern 1/32 mfr's gears, they'ere almost exclusively 48 (nominal) pitch, and you can combine them in any ratio that will fit your car. NOTE WELL that for sidewinders, the trick is to maintain the same diameter pinion and the same diameter spur. Example: Slot.it sidewinders use a 6.5mm pinion and an 18mm spur. That totals 24.5mm. You can use any combination of 6.5mm pinions and 18mm spurs... OR... you can use a 7.5mm pinion in combination with a 17mm spur. Again, 24.5mm total. If you use an inline chassis, no problems with any combination so long as your chassis can accept the pinion's diameter (almost always smaller than sidewinder pinions). and you make your club's clearance spec.

                      As to the use of a Scalextric Mustang... to each his own, but you will be a a severe width handicap unless your club allows you to extend your wheels past the fenders (mine does not). I use a Scalextric Porsche chassis with an Amato 3D printed chassis and Slot.it mechanicals. I have also done the same deal with a Scalextric 71 Camaro (also wider than the Mustamg).

                      Take a look and see what the experienced fast guys are running.

                      Comment


                      • #12
                        Originally posted by HO RacePro View Post
                        SlotsNZ, you missed my point. You may need a refresher on how a set of spur gears work.

                        In a simple spur gear setup the pinion gear and the spur gear are spaced so their pitch diameters 'roll' against each other. If you keep the centerline spacing fixed, a decrease in the pitch diameter of one must be matched by an increase in the pitch diameter of the other.

                        Now the relationship between the number of teeth on a gear and its pitch diameter is linear. Adding a tooth increases the pitch diameter by the tooth pitch divided by pi. Subtracting a tooth decreases the pitch diameter by the same amount. This is independent of the total number of teeth on the gear! It comes back to the definition of pi. That is the circumference of a circle is equal to pi times its diameter. A linear relationship.

                        If you can get your head around the fact that this works for ANY size gear -- and it is a bit counterintuitive, I admit -- you can see how you can change ratios without changing the centerlines. Add or subtract a tooth from the pinion, you subtract or add a tooth to the spur. It works.

                        And of course, if you add or subtract multiple teeth, it still works.

                        My apologies if you are not up to speed with gear pitches and pitch diameters. That's understandable. It is a strange fact that you can earn a mechanical engineering degree without ever learning about them! But if you want to take a trip down the rabbit hole of gear theory and design the internet is your friend.

                        It is a VERY deep rabbit hole!

                        Ed Bianchi
                        No Ed. I did not miss your point at all. And I don't think I need a refresher on how spur gears work. I have been distributing them for several slot car brands since 2007 and written technical articles on involute gears which have been checked over by an engineer to make sure I had got it right.

                        What DM said in his reply, and I implied, was that you change the gear ratio so much at once by shifting the tooth numbers of spur and pinion in opposite directions, that you may shift much further than needed, and automatically miss out on some ratios which may be the sweet spot in between. And there is no need to swap out a pinion when you may just wish to conveniently swap a spur gear one tooth either direction to achieve the braking and acceleration you want.

                        I am intimately aware of the tooth angles of Slot.it spur gears and pinions of various tooth numbers, for both O.D. of spur, and 5.5 and 6.5mm pinions, and how the shifting pitch diameter contact point is created by the shape of the tooth angles for their various combinations of both pinion diameters and spur tooth numbers across the range, and how that ultimately affects actual mesh.

                        Slot.it and NSR tried to fill in that particular rabbit burrow with the way they have designed their gear sets.
                        The "dark art" as DM called it, has been made easy for the man in the street.

                        You are actually changing the centre line, that is the whole point of the design of these gears, and as much as possible, you are trying to use combinations where the ACTUAL modulus of both gears is similar.

                        But to do that, you need a combination of chart/database of effective pitch or modulus; - and experience - the chart at bottom only covers two brands, as it is quite dated, I haven't added in ScaleAuto, Thunderslot or Sideways (now that some of their gears appear to come from other than Slot.it)
                        It was partly compiled by someone else, and uses pitch rather than modulus; and I am suspicious of a couple of the numbers, especially given the particular number when you see the shape of that tooth, where it sits in the tooth range for diameter; and hear how it sounds when mated with a particular other half of the gear combo where it SHOULD be smooth and silent...
                        But the chart forms a good start point. I haven't come across a better one. If you have, I would be grateful if you shared it.

                        After a while you do know intimately by experience what is going to be the result when you swap a particular spur out by one tooth, while maintaining the same pinion.

                        For instance Slot.it 6.5mm Ergal 10 tooth is 46.89 pitch, the 18mm 35 tooth spur is 52.22 according to the chart. This combo SHOULD be loud and inefficient, but I have a stealth bomber of a Group 5 as sidewinder which has run this combo unchanged since a proxy series in 2015, and through 4 years of club racing. Hardly ever been beat on any track.
                        I wanted that low ratio as I used a Slot.it 29k, which only has 160g/cm torque and buckets of RPM, and it is weighted down to 88 grams for proxy racing stability.
                        I thought I was sacrificing efficiency and quietness to get the gear ratio desired.
                        But you just cannot hear it running, never have.... beggar me.... shouldn't work, does. - The chart isn't everything, but it is a good place to start unless you want to use a more complicated method of manually calculating pitch circle diameters for every instance of choosing gears.

                        I have probably built 250 plus competitive sidewinder cars with the Slot.it parts, and combined those gears with those of two other makers who have compatible pinion and spur tooth angle and modulus for Slot.it pod, and for upgrading fixed chassis Scalex models. I know which combinations are quiet, and which are noisy due to teeth sliding against each other - due to different modulus, which don't work so well. - That said, sometimes to get a gear ratio which works best for that car, we sacrifice somewhat and accept a bit of friction and noise.

                        Take a look at the shape of the teeth on these pinions

                        Quite clever our mr "Smith" of Italy and his cohort M. Gibertoni - but that is to be expected with a pair of ex Ferrari F1 engineers.

                        Slot.it did also change the tooth angle and effective pitch diameter between the old GS06 solid spur gear, and the current series GS1836 lightened gear.
                        Some people miss that and wonder why the same ratio sounds different when they use one series of the 36T spur versus the other with a particular pinion in common.



                        So no, I do not think I need a refresher on how spur gears work, and perhaps more importantly - how THESE spur gears and pinions work together.

                        Perhaps you could outline your experience in setting up these particular cars with these gear sets to share with us.
                        Last edited by SlotsNZ; 02-13-2020, 05:49 PM.

                        Comment


                        • #13
                          The problem with most 1/32nd scale cars is that the position of the motor is fixed. Since you can't easily change the position of the motor with standard pitch gears you would not be able to get a good mesh if you wanted to change gear ratios for an anglewinder or sidewinder car. Most sidewinders and anglewinders use a 6.5mm diameter pinion gear. Scalextric and Fly sidewinder cars use a 19mm diameter spur gear and just about everyone else uses an 18mm diameter spur gear.
                          Here is a gear chart that I did years ago for Slot.it gears.

                          Slot.it now has even more gears, I don't have a chart that includes all of those, however they all mesh well, except that the 13 tooth pinions are noisy. It is all well and good to understand the theory behind gears with a varying pitch diameter, but all you need to know is that they work. With anglewinder gears you can fine tune the gear mesh by moving the spur gear from side to side.

                          Comment


                          • #14
                            Dangermouse,

                            You do understand that business I explained earlier about spur gearing on fixed centerlines.

                            I admit that increasing or decreasing the tooth count on the pinion gear will have an outsized effect on the gear ratio. When it is possible you make fine adjustments to the gear ratio by adding or subtracting teeth from the spur gear only.

                            You can do that by shifting the centerline spacing, or by fudging the pitch diameters of the gears by altering the tooth shape. Ideally you change the centerline spacing so you can use standard gears. If you fudge the pitch diameters you should use matched pinion and spur gears, so their tooth shapes are compatible.

                            All of that said, there are strange and wonderful things that can be done with gearing if you abandon the standards. I remember a case where someone developed an elliptical gear for a bicycle, so the mechanical advantage could be maximized at the top and bottom of the stroke, and reduced at the middle of the stroke, when the rider can exert the most force.

                            Slot cars are very, very simple machines in principle. In practice they can be amazingly complex.

                            Rabbit holes abound.

                            Ed Bianchi

                            Comment


                            • #15
                              Originally posted by HO RacePro View Post
                              ...... or by fudging the pitch diameters of the gears by altering the tooth shape......

                              Ed Bianchi
                              That is all it has taken for the last 15 or more years Ed; as the 1:32 hobby makers, led at the beginning by Slot.it who I think were the first RTR maker to do it, long since filled in that rabbit burrow.

                              - And I think DM was asking with a bit of tongue in cheek. I know him from other forums, and he has been building cars for many years.

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