Carisma Blog - Part 2
RC guru Dez Chand continues his indepth review of the Carisma F14 1/14th scale Formula 1 car.
Having trimmed and painted the gorgeous little body shell last time, we turn our attention to the mechanical aspects of the smallest F1 car that is topping everyone’s wish list this Christmas!
The Carisma F14 comes factory assembled so you can literally just wire it up and hit the track, but take the time to give it a good once over and you'll benefit from the knowledge of the adjustments and settings available on this race spec chassis.
Unlike most pan cars, I noticed the rear ‘T’ bar on the F14 is indeed a bit special, more like an ‘H’ than a ‘T’ bar, being retained at both front corners, and pivoting on a central bump stop at the rear with side springs whose pre-tension can be altered via simple grub screws to affect chassis tweak! All you need is a 1.5mm hex driver and you can easily balance the chassis to sit flat on the track with even pressure on both rear wheels.
The rear motor pod is controlled by an oil filled damper and spring for which preload spacers are provided, and the roll damping is regulated by a double sided slipper plate whose twin spring arrangement keeps them acting on the extended motor pod upper deck.
Top Tip - Keep these plates well greased to avoid grip rolling during quick direction changes. Likewise the 'O' rings within each slipper plate need lubricating to maintain a smooth action as they move very slightly up and down the central anchor post when corning.
The rear axle sits in bearings housed in eccentrics to adjust ground clearance in the usual way, while the front suspension sits on spacer discs which can be added to drop the chassis really low, or swapped for thinner spacers (or even removed) to jack the car right up.
The front suspension uses regular fixed lower arms with a top control link incorporating a turnbuckle that alters camber, with spacers on the top arm pivot to adjust castor. Simple effective and easy to keep symmetrical across the car for even handling.
Top Tip - just remember to turn the camber turnbuckles back a little after any adjustments, to centre the top ball joint and avoid binding the steering on the king pins.
The Ackerman is set by the link positions on the servo saver, but the front wheel alignment can be adjusted by flicking off the steering links rods to adjust their length and affect Toe-In or Toe-Out. The fixed axles carry ball bearings within each wheel, and the live king pin slides through the bottom ball joint, controlled by the small spring below. The whole suspension package feels smooth, balanced, can be simply tuned for optimum handling and is easily maintained. It may look small and fragile but in over a dozen race meetings I’ve yet to see a front end failure, they really are tougher than you might expect! Now, I don’t crash much, but I know a few people who do and even they can’t find the F14’s Achilles Heel!
The wheel nuts can be tightened up sufficiently to bind the front wheel bearings, so do them up carefully to the point the wheels stop spinning freely, then back them off gradually until you achieve minimum free play and a free rolling axle for maximum efficiency. If fitted nyloc end first where the nuts tops are narrower they only press against the inner bearing race, plus there is a lot further for them to turn before they can get off the nyloc and make a bid for freedom!
Likewise the left rear axle nut can be over tightened to bind on the bearings, while the right rear wheel nut affects the action of the geared diff, so they need careful adjustment. A tighter left wheel nut will produce a solid axle, while a loose setting gives a free diff action that will happily ‘diff out’ when accelerating hard out of corners. With fine adjustments you can achieve a good diff action but the ultimate solution is the optional ball diff for the F14, so we’ll try that once we’ve given the standard kit a fair crack of the whip.
Join us next time when we'll look at battery, motor, gear ratios, tyre choices, options and special modifications based on real track time and race testing.
ADDITION - Check out the Carisma F14 in action below filmed and contributed by Jordan Norwood.