Build Tips for Sakura Zero S

Transcription

1 Build Tips for Sakura Zero S Revision Control Revision Revision Notes Report By Reviewed By Rev0 First Draft Marc Baynham

2 Introduction The way in which a competition electric radio controlled car such as the Sakura Zero S is built will have a huge impact on how well the car runs, and therefore a direct impact on how competitive the car will be. This guide has been produced primarily to help anyone who has bought a Sakura Zero S as part of the SDRCC SPEC class kit package. The hints and tips in this guide will help first time builders of R/C cars to build the car without too much outside assistance. During the build of the car featured, the instruction manual was followed closely. It is recommend that you read through your instruction manual from start to finish before starting the build. The build tips have been grouped together by step, so these will correspond to the steps in the manual. The kit comes in bags of parts, these are clearly marked and in the top right of each page, the manual indicates which bags are used in each step.

3 Preparation During a build it is always best to work in a comfortable, well lit environment. Keep your workspace free from clutter. If you are not building the car in one sitting utilise plastic sealable boxes to keep parts in should you have to pack the kit away part way through the build, as below. Recommended tools and items for the build. Small Phillips and Slot head screw drivers. Needle Nose Pliers Side cutters Hobby knife 1.5mm, 2mm and 2.5mm allen keys (2mm Allen driver recommended). 7mm nut driver/socket for wheel nuts. Dremel/Junior hack saw to perform a slight modification. Glue Set of 4mm Nyloc wheel nuts (to replace the existing wheel nuts). Two or Three cable ties Emery cloth Grease to lubricate screw threads (Candle wax or soap could be used). The kit supplied turnbuckle tool can be replaced with a 4mm turnbuckle tool (optional).

4 Step 1 I had a little problem lining up the large gear with the pin. Mark on the tooth side of the gear with a marker pen where the slot in the back of the gear is, this will help you to line it up. When putting the o-ring onto the gear diff housing, push the o-ring as far as you can.

5 When you put the 3 shims on top of the o-ring, use a nut driver and push down the shims. This will seat the o-ring. Ensure the rubber diff seal is flat, thread the screws through the seal carefully. This does not seat easily, ensure the seal is seated before tightening or the diff will not go together correctly. Use a little grease on the screw threads on the gear diff housing. I pre-threaded the screw holes..

6 Be careful not to over fill the diff with oil. Follow the instructions. Ensure the diff action is smooth by twisting by hand. Step 2 Take care not to over tighten the 4 screws in the pulley. Step 3 Sand round the sides of the chassis and coat with clear nail polish or superglue. This will help to stop the chassis splitting in a heavy impact. Use some grease on the threads of the suspension mounts. Take care to ensure the suspension mounts locate correctly. There are small pins on the mounts which locate into the chassis. I prethreaded the mounts off the car, then fitted them.

7 Step 4 The build starts to get a little more tricky now, as we have the first major on chassis assembly. Use grease on the threads of the screws into the plastic centre pulley mounts. You can prethread these off the car as I did but take care to ensure the screws are going in straight.

8 Assemble the motor mount and Left-hand pulley mount off the car. Do not tighten up this assembly fully. Next, fit to the car, again not fully tightening all the screws. Gradually tighten up all the screws until each screw in the assembly is tight. This will help the parts locate correctly. Take care when fitting the centre gear adapter that the 2 small shims either side locate correctly. Step 5 Take care to pre-thread all the screws or at least use a small amount of grease on the threads to help keep the threads cool and lubricated.

9 There are small locating pegs on the bulkheads, ensure they locate into the chassis correctly. Do not fully tighten one screw in the bottom of the bulkhead before fitting the other. It is best to screw in the first screw part way, then screw in the second screw part way, and then tighten them equally a little at a time. Steps 6 & 7 Ensure the bearings are pushed all the way in on the diffs before installing to ensure they can be fitted correctly. I recommend installing the rear gear diff first, then installing the rear bulkhead covers before installing the front diff and bulkhead covers. This will stop the bearing holders moving while installing the other diff. The front shock tower locates onto the front bulkhead covers. When you install the bulkhead covers, don t fully tighten the screws. Install the shock tower loosely, then tighten the screws on the shock tower and the screws on the bulkhead covers together, a turn or so at a time. A dot of white nail polish or tip-ex in the positioning mark in the bearing holders will make later setting of the positions a lot clearer. I used a tiny drop of white nail polish on a pinhead to fill the hole.

10 Step 8 Use grease to pre-thread the plastic parts as per picture below; Ensure the Steering saver rotates freely when fitted. As per the manual, use a little thread lock on the M3x8 screw which holds the steering post in place. Step 9 When locating the steering system, tighten both screws equally, don t tighten one screw fully before starting the other. Step 10 Fit the top deck to the chassis, if you have to force it in place, file the ends of the top deck until it located freely. This will ensure the car can flex correctly, which will generate grip.

11 Tighten up the top deck screws equally. Put the car on a flat surface, and place some force on the shock towers or to the chassis to keep the car flat.

12 Step 11 & 12 Thread the M3x10mm screw which screws into the wishbone in and out 2 or 3 times to ensure that it is free. You will require to make fine adjustments to this screw later, so having to force it will not help. Use grease on the screws on any plastic parts to keep the screws cool while threading. Step 13 Thread the M3x6 set screw which screws into the rear upright, in then back out before pushing the outer pin through. This is to prevent any plastic getting caught. Use grease on any fittings which you have to screw into plastic. It is advised to thread the turnbuckles in and out 2 to 3 times to free them up before fitting. Ensure the ball caps are free and do not bind when fitted. Pay close attention to the red text on the bottom left of the page- cut the inserts from the foam bumper and place into the diff outdrives. Step 14 Thread the M3x6 set screw which screws into the front C-hub, in then back out before pushing the outer pin through. This is to prevent any plastic getting caught. Use grease on any fittings which you have to screw into plastic. It is advised to thread the turnbuckles in and out 2 to 3 times to free them up before fitting Ensure the ball caps are free and do not bind when fitted.

13 Step 15 As mentioned before, tighten each screw up equally. It is advised to screw in the first screw mounting the shock tower until the button head just touches the shock tower, then un do the screw 1 turn. Repeat with all screws, then tighten them up a turn at a time until all tight. Step 16 Pre-thread the bottom ball caps before fitting to the shock shafts using a screw and a little grease. Put the shock silicone cap and the shock o-rings onto a dish or piece of plastic/inside one of the parts bags, and put some shock oil over them. Soak this for 20 mins, to make the parts supple. Ensure there is a little shock oil on the o-ring and spacers before pushing through the shock shaft when fitting. Ensure the shock pistons do not have any small plastic flashes left from the manufacturing process. Follow the manual when it comes to putting the bottom caps on- see top right of page. Once the shocks are assembled, put them in a suitable stand. I used a plastic tub with 12mm holes drilled in the top (see photo). Fill with shock oil to the top and leave for at least 30 mins, preferably longer if possible to allow all the air out.

14 Once the top caps have been fitted, I would advise cleaning the shocks with brake cleaner or a similar solvent to remove excess shock oil from the body. Step 17 As per Manual Step 18 Servo Install the servo as per the manual. When mounting the servo to the chassis, use the outer pair of holes in the chassis and also note the orientation of the servo mounting posts. See photographs.

15 If you have a SDRCC Spec Class package, use the three items as shown, you ll be using the servo saver with the three largest holes, plus the item on page 20 of the instructions, top left of the parts list (a circle) and the item marked Futuba (Tamiya). Note that there will be some parts left over at this step. Motor For the Etronix ES028 servo included in the SDRCC package, don t use the M3x8 screw from the kit, instead use the screw supplied with the servo to screw on the servo saver. Once all the rest of the electronics are installed, power the car up. You may have to remove the servo saver (the assembly from step 18), and re-centre it on the servo. The bellcrank (assembled in step 8) should be in the centre of the chassis. Adjust the linkage or transmitter trim to get the bellcrank in the centre. If using the HPI 15T Firebolt motor, you will need to utilise a spacer plate available from SDRCC along with two M3x14mm screws. See Below picture;

16 To get the rear of the two motor screws in place you will have to feed it in diagonally past the outer edge of the white spur gear and into the hole in the pink motor mount the screw head will not fit through the holes in the spur. After putting the screw in position, pass the 2mm hex driver through a hole in the white spur gear to tighten the screw. See photo. Depending on the angle (impacted by pinion size), a ball-head hex driver might work better. If you can t mount the motor with the spur in place, roll the front drive belt off the front differential to create some slack then remove the spur gear assembly by removing the screws either side of the spur gear shaft and re-fit the spur afterwards. Receiver After threading the receiver antenna through the mount post, be very careful fitting the screw through the chassis to the antenna mount post. We almost trashed the antenna wire when the screw went into the hole with the wire in it by mistake. The two holes are 0.5mm apart so this can happen very easily when working under the top deck. See picture below for layout of the wiring;

17 Step 19 In order to allow the easy fitting and removal of the pinion gear without the removal of the motor, a small modification is required to the plastic battery mount next to the motor. Install the other battery mounts as per the kit, and cut the left rear one as per the pictures below. This can be done using either a dremel, or in the example above, a junior hacksaw. Take care when using cutting tools. Left Rear battery mount, prior to modification.

18 Modified left rear battery mount shown along side unmodified Right front battery mount. Modified battery mount shown fitted. This will allow easy removal/changing of the pinion gear. Remaining Steps As per manual. Use grease to thread any plastic parts. Missing Parts Occasionally, parts may be missing from the kit or package. It is difficult to check the kit before building, so should you encounter any missing parts, contact the person you bought the car from and they will supply the parts quickly. Setup The setup of a radio controlled racing car is very important. After some initial testing, I have found the kit setup to be pretty forgiving and easy to drive with no adjustments to the setup made so far. This will ensure the car is easy to drive for new drivers. For help with setting the ride height, camber, tow, etc, bring your car along to SDRCC and someone will help you. Specialist tools are required to setup an R/C racing car, and we don t expect new racers to have these tools or have the knowledge to set the car up, there is always help available.

19 Further Help use addresses on the site to get in contact with the club. scroll down for the Stonehaven section