2ème partie: Préparer sa Xray NT1
Categories : Trucs et astuces
For those who have already followed the first part of the preparation of your XRAY NT1, you will find here the next step with: shock absorbers and electronics. If not, start with the first article to have the first steps
In this topic, we will see step by step how to prepare the shock absorber in the best ways and scalable ways to maximize the handling of your car.
1st step :
Disassemble the damper, empty the oil and clean everything.
Note: If during the disassembling your oil is black, it is dirt that has become lodged at your O-ring place. In this case, remove the nut, remove the o-ring and clean everything.
2nde step :
Fill your shock absorbers with the oil viscosity of your choice up to 0.5mm below the limit of the shock absorber body.
I recommend the Hudy oil with which I never had problems of constancy: https://goo.gl/fdgbTi
I then use an automatic vacuum pump to remove all air bubbles present in the oil in order to get the most homogeneous damper possible.
This pump can also be used for differentials which is very convenient in view of much higher viscosities and whose bubbles are even harder to eliminate.
Available here : https://goo.gl/zwsHHK
4th step :
Once all bubbles are removed, it is now necessary to adjust the rebound that corresponds to the decompression of the damper. It is possible to adjust the output speed of the rod and its output percentage
In 90% of cases, I use an exit percentage of 10%. We will see how to get this value.
1) Take out the dampers from the vacuum pump
2) Put the membrane in place and press with a screwdriver to remove the excess oil (photo at bottom left)
3) Tuck the rod until you have 1mm between the joint and the nut. (Photo bottom right)
4) While blocking the rod in the position, take again the screwdriver and press on the membrane in order to evacuate the surplus of oil
5) Close the damper
Repeat this for the other three dampers to have exactly the same rebond and thus to have the same car handling to the right or left.
The receiver battery
Let's start with the receiver battery.
I use a LiPo 1500 mAh battery. The capacity is sufficient for the long finals.
The battery I use is extremely flat, only 11mm thick which allows you to use the tank in a lower position and therefore lower your center of gravity. Very useful when you know that with the full tank you have 75g more correspond to 5% of the total weight. To lower it by 4 or 5mm can only be beneficial.
As the battery is less thick, it is a little longer. It is therefore necessary to grind the left battery holder with a Dremel as in the picture below so that the cables can be perfectly free.
Put the battery in place and use a reinforced battery tape to secure the battery. With this tape you are sure that the battery will never be detached.
The radio plate
To have a clean electronic assembly and without risks of severed cables here how to do:
-Thread the steering servo and transponder cables between the radio deck and the steering servo bracket to make them stand out between the throttle servo and the steering servo.
-Plug your cables to your receiver
-Close the box
-Fix the power cable to the radio box using the HUDY body fix to secure the attachment.
Available here: https://goo.gl/RDMA3W
The throttle linkage et the steering rod
On the throttle linkage, I secure the gas stop with 2 stops. On the second I put a button head screw to open the carburetor when starting the engine without radio control.
Against the carburetor joint, I also mount a stop with a button head screw with a piece of fuel tube in order to position the carburetor elastic. The fuel tube will not attack the elastic on the threads of the screw.
Regarding the steering rod, in order to have the optimal adjustment so that the steering horn is at 90 ° when the wheels are neutral, I put 4mm between the two joint, where the two orange washers are