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Well after my mixup on my idler/jackshaft stump puller setup I re-grouped and built this chassis for a vintage Indy car body a Lotus 56 turbine. It will also fit other narrow F1/indy type bodies and can be made even much narrower and may even fit some 1/32nd scale bodies.

It is a combination inline drive to full sidewinder final drive. With careful alignment the gear set has very little extra friction that I can find and in trials last night it runs great. Handles great and has a more forward weight distribution to get some of the sidewinder or angle winder motor weight more centrally located. I think I will be building a few more of these for some vintage open wheel type cars. I may even try this with a front motor and drive shaft back to the inline crown gear

The motor gearing is easily changed and the indler gears are now a 1-1 ratio. With a very smooth mesh with the fibre reinforced plastic gears used. The body floats up and down about .032 with the two narrow side pans that float with front and rear U shaped wires in retainers to main chassis. The front wheels independantly rotate with a TSRF e-clip added to one side on the axle.









The body shown is a test pull of a mold I am making of the Indy Turbine car. The mold will be refined a bit more and this one was just mocked up quickly to check for fit.
 

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Graham Windle
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Great work as usual Larry ,But can you fill us in behind the reasoning for the set up ,Is it to remove the lateral force against the motor shaft under cornering ,if thats the case then I understand why ,but wont the frictional losses of all those gears outweigh any thing gained through the removal of these lateral forces ?
 

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Funny enough, but I've had a similar design in the back of my mind for 1/32 F1 chassis for ages (yeah, yeah, yeah... No, honest!). I thought an idler arrangement would do two things- allow me to put an S can further forward in the shell where there's a bit more room, and also make it possible to hide a series of smaller diameter gears with stepped increments under the dummy engine without having to carve big ****** out of the model gearbox. Also with a mini-can, you could get the CG right down with the motor on the bottom rail of the chassis and the idler gears stepping up to the back axle. I'm still looking for the right gears, but I'm thinking this is worth pursuing again now.
Thanks Larry! Great job! But... could you have fit the spur gears inside the motor bracket rather than outboard?
Lovely shell, too.
Brilliant bit of work. Who would think there's still new stuff to try after all this time?
 

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Nice work!
I remember a fellow BSCRA racer called Gary Fletcher who built a similar geared arrangment on his 1/32 F1 car, think it made the main F1 final at the Nat's in the late 80's.
[oneofwos]
 

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Graham Windle
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I too remember that car john , I think he built it like that because there was a wider range of ratios available by using spur gears at the time
 

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Al Schwartz
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QUOTE But... could you have fit the spur gears inside the motor bracket rather than outboard

It appears to me that this would work if the shape of the rear cranked "U" were altered to provide more clearance.

EM
 

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John or Grah- do you have any other details of that car? I'd love to see. I'm still puzzling over what sort of gears might make it work.
 

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Graham Windle
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I have a pic at home if i get time tonight to use teh computor (my wife is revising for the last exam in her degree) I will post it (unless john beats me to it ).
 

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Discussion Starter · #12 ·
Graham the friction caused by the two extra gears is very minimal. As the mesh has been set very carefully to allow a loose mesh and not too tight. It was designed to get rid of the wheels side loads on the inline drive and provide the torque advantage the anglewinder, sidewider provides. Gear changes can still happen easily with the pinion and crown gear instead of changing the sidewinder mesh and gearing dimensions. Ball bearings would also allow a much less friction setup if it comes to that point

It could have the gears mounted inside the frame with some more planning and the whole rear end could be built about as wide as the motor and should then fit in a 1/32nd scale open wheel body to get the sidewider drive advantage reputed to it.


Anyway it is a fun project that will go a bit farthur along in the next few months. I am sure, I am not the first to have built one or want to claim such, just have not seen any yet.

The 4 bushings used now are the Parma Flexi IV square, off set hole type, as they are easy to solder music wire to and to set ride height and wheelbase a bit different. These are the 3/32nd ones.
 

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No chance in John beating you as John still has no clue in how to post pictures!!

I think there might be something posted on Chris Frosts's site in the historic section, i do remember an article in the BSCRA mag last year or the before but don't have any copies to be able to check. I do have a spare spur gear he used on that project and i do remember bevel pinion being used to take the drive across the chassis but thats all i can remember.
Cheers

[oneofwos]
P.S: "I have some pictures from our 1/32 retro meeting of some of Chas Keelings original retro cars, anybody willing to post them on this forum for me? please Email me"
 

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My first ideas had two pinions on an inline layshaft built into the motor bracket with a couple of old motor bearings on an old motor shaft; One bearing fitted near the motor bearing itself, the other between the two pinions and mounted to the side arm of the bracket. The first pinion would mesh with the motor pinion, and provide the step-up from the motor centre line to the higher axle centre line, plus a slight drop in ratio. Then the second pinion would be a very fine pitch meshing with the smallest diameter crown gear I could find, on the axle itself. This was to have been with a hopped-up HO motor in my Lotus 43. This has now been replaced with a Beardog Mini.
Now I'm thinking that Larry's set-up looks a whole lot more efficient and easier to build, if I can find the right (small diameter) spur gears to fit under that 1/32 H16!
 

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Phil Smith
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"if I can find the right (small diameter) spur gears to fit under that 1/32 H16! "

Have you tried the Betta gears, these are the same fine pitch as the old Taylormade gears and go down to a 9 tooth pinion , the contrates go down to 34 teeth and at this size are only about 12mm dia.

Betta are available at 01704 229342 (no website)
 

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Graham Windle
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QUOTE Did you ever find that pic, Grah?

Howmet I know where it is but I ve been at slot tech all week end for the porsche chalenge ,failed miserably but set ftd

I'll try tonight
 
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