Schumacher CAT XLS Build Part 7 - Electronics Installation and Important Under Tray Modifications

Catxls Build Part 7 - Electronics Installation.

(Very important lower body shell modifications)

Thank you for joining me in Part 7. 

I will be installing all the parts I described in Part 6.

Here we go, again......

I now need to go back to the Schumacher build manual Step 49 on page 42.

In Step 49, I am instructed to fit the steering servo, following the instructions. However, DO NOT fit the servo yet. The ball joint that I will fit to the steering assembly will foul the under body shell, as can be seen in  the picture below.

As you can see in the above picture, I have used a pencil to mark out the area the offending material needed to be removed. Again, this is something never mentioned in the Schumacher build manual. 
Right, it's time to get the rotary tool out, again.

The picture above shows the clearance needed.

Also in Step 49, I am instructed to fit the other ball joint to the servo saver. At this point I am instructed to drill out the hole for the ball joint on the servo saver with a 3 mm drill. Do this before fitting to the servo and be careful, I almost ruined mine, as can be seen in the picture below.

Now I can fit the ball joint and fit to the servo following the instruction in step 49.

I am instructed to ensure the tie rod gap is set to 11 mm as shown below.

With the correct distance set, fit the steering servo in accordance with the Schumacher build manual as shown below. Servo fully fitted.

At this point the radio gear was connected to test the correct operation of the steering servo and assemblies. All good, happy days.

In Step 50, the manual provides information of fitting the motor. After fitting the motor and pinion, set the motor exactly described in the manual. I use a different method using a strip of simple printer paper but 75 gsm is the best. I roll it between the spur gear and pinion, then tighten. If you are uncomfortable using this method, please refer to the build manual instructions.

The pictures above and below show the paper method I use to set the spur and pinion gap.

The picture below shows the steering assemblies with the top body shell in position.

In the picture below are the double sided pads I will be using.

And then added to the speed controller and receiver as shown below.

I will now follow the manual on page 43 (Step 50) and place the electronics in the advised positions. As shown below. Also note below, the battery is not secured. Oh dear!!

As you can see from the picture above, it was a calculated squeeze to get everything in. This is mostly due to excess cables from all of the electronic components. If I was going to race this buggy, I would certainly make them to measure and shave off the excess grams. If you look at the belt cover, you can see a small hole. This is advised in the manual. This is to check the main belt tension. However, no deflection figures are in the manual.  I have not yet set up the receiver antenna as I don't want to drill the shell, after all, it will be on a shelf soon.

The picture above shows the Cat with all the components needed to run. As you can see, that 410 gram  payload has dropped the buggy quite considerably. Maybe a perfect racing height. I'll let it settle for a couple of days after a test drive, in about five minutes.

 At about 4 pm this afternoon, I lifted the rug in the front room and revealed the laminate floor. I then switched on the handset first (a major rule with any RC vehicle), I then switched on the car. I knew the electronic speed controller was set, with brake and reverse that I had previously set up for the Optima. The only thing I had to do was trim the steering true, ensure forward and brake were still programmed. I then fitted the upper body shell. With all the specifications identical in each buggy, it was time to test.

Ok, your just going to have to take my word for this.

Within seconds of driving the buggy, I was in awe. And within this brief moment, I realised why the buggy had been so competitive back in the day. The acceleration for a 27 turn motor is impressive. The turning circle of the buggy is awesome.  My only regret is using the Altura servo. Again, if I were racing, I would use a lot faster servo. Over looking that, what a buggy. Way faster, leaner and more agile than an Optima, but I expected that. We were beaten weekend after weekend by CAT XLS'. The CAT is quick to go, quick to stop and fierce in turning. I was doing doughnuts left to right on command, on a 27 turn motor with a standard Nimh battery. I am very impressed with this buggy on the first and maybe the last run. See below....doh!!

As you can see from the picture above, I was having too much fun and broke it. Without a doubt this was my fault. Testing this in this house was very stupid. I am pretty lucky that was all that was damaged, including the furniture.

I have ordered the parts. Parts number U7210. They come in a pack of four. I have to admit that the centre pages of the manual are ideal for identifying parts and part numbers when you damage something. So, whilst I was buying U7210, I accidentally ordered a new high speed servo (Alturn AAS 752MG) and a Hobby-Wing Quicrun 1060 electronic speed controller. With this esc, I can run a 2S lipo battery with a 17.5 turn motor. Oh dear,. I see further spares needed in the not so distant future.

Thanks for reading. 2020