Scania airport fire truck

[egronvold]

Thumbs up! Nice weather for painting these days

[Wombii]

The weather has really been perfect for painting this week, except for the pollen and other stuff in the air.


Very happy with how the RM60 roof monitor turned out in yellow.

[Wombii]

I've tried to make as much as possible in separate parts so I don't have to do a lot of precision masking.

[Wombii]

The chassis looks good in black.
Motip etch primer + Motip high gloss black.

[Wombii]

I couldn't take it anymore. A bit of sanding, gray primer + the rest of a decade old can of Tamiya flat black, then white primer and resprayed the whole thing with yellow. No more light bleed, but I added so much paint that I need to shave down the rolling shutter door panels to make them fit again.

Two observations: I'm now out of primer again, and ten+ year old paint cans can technically work, but it's more like whipped cream than a precision instrument.





It's bothering me a bit that the cab is a slightly more saturated yellow than the rest, but I'm working hard on talking myself out of repainting that too.

[egronvold]

You aim for perfection, that’s for sure

[Wombii]

Doing my best. Fortunately, most of the flaws don't show up well in the photos


Hit a roablock for a few days. I had so much lovely articulation in the rear, but never thought to check with the rear dog bone. Turns out that doesn't like articulation at all, so it kept falling out or binding. I found out that I also couldn't easily replace it with a proper drive shaft, because it's so tight and the 45-55mm type that would fit would end up stretching too far and disconnect. The only way I could find was to limit the travel enough by mounting the stock shocks. They prevent the wheel from dropping too far, but there will be a lot of force trying to pull them apart.





Started wiring everything up and final assembly (hopefully).
Didn't double check the switches when I soldered the last time, so they got mounted upside-down. Got a chance to turn them around after painting, so now USB power is selected by flipping them down towards the USB port.













Floor for the cab interior.

[skeeter]

Sorry to hear that you had to limit the travel. The amount of wiring in this project................it looks difficult to keep it all sorted.

[egronvold]

Originally Posted by skeeter

Sorry to hear that you had to limit the travel. The amount of wiring in this project................it looks difficult to keep it all sorted.

I think the wiresalesman sent him a Christmas card last Christmas

[Wombii]

Rainbow colored ribbon cables help with keeping it under control, but sometimes it's just easier to change the Arduino program to match the connections . I'll post the full wiring diagrams when they're done. I'm glad I've documented everything since the beginning now that I've taken everything apart and started rebuilding it.

I put a cheap 5$ servo in as the gear servo, but apparently never actually tested it. Today I've spent most of the day troubleshooting and ended up swapping it out, because it's got full right deflection as the internal center position. No way to trim that out. Never seen that before. Again, the lesson (still not) learned is to test everything properly before building a truck around it.

[frizzen]

I dunno what they're going on about, it could still use more wires. Looks pretty empty to me. Then you can start tying them into harnesses or raceways so its pretty.

[Wombii]

I should have laid out all the wiring before installing it for some photos


The cab is now a slightly different shade of yellow, even though everyone told me not to risk ruining it with another coat from the newer paint can. Fortunately very happy with the results.



Accelerometer for roll over alarm connected to an Arduino that acts emulates a bunch of telemetry sensors, transmitting voltages, water tank level and accelerometer value to transmitter.



Middle distribution board mostly populated



Main board in the back with most of the wiring done. Missing the wires for the light mast and sound module.


Fully wired tail end. It looks a bit messy because I make sure to leave enough slack in case of future repairs or modifications.





Detailing the shutter doors




Ceiling:
Glued in some LEDs above the ceiling panel and soldered them up. Looks a bit messy, but it works.


Yellow dome lights when it's parked:


Red map reading lights:


Painted the roof platform TS-17 gloss aluminum:





Simple but very effective mod for the cheap chinese light buckets. Styrene tube painted with Molotow liquid chrome helps with the rotating beacon illusion.



Made one more piece for the side steps and got them painted. The hanging front steps are fastened with a small bit of paperclip so they can easily be popped off.

[egronvold]

Wiring is insane...

[Wombii]

Originally Posted by egronvold

Wiring is insane...

I forgot to take a picture of the mess behind the battery switch panel, and I'm afraid of opening it up again.



Shutter doors painted with TS-30 Silver leaf. Looks much more like aluminum than TS-17 gloss aluminum. White and navy blue stripes on the cab is Model Technics trimline tape. Painting the Scania letters on the front with a Molotow liquid chrome pen was a lot easier than cutting and applying the letter decals. (Do that after the final clear coat and don't touch it).






When I made the rear doors I didn't consider the curve of the windows. I may have posted an image earlier of me boiling an extra set to straighten them. While that technically worked, it also left them with some stress damage. To try and fix that I sanded away a lot of material on both sides with 180 sandpaper, then 600, 1200 and 2000, leaving an evenly frosted surface. Acrylic polish is expensive, but somewhere online recommended whitening toothpaste, and that worked extremely well. (If it's still too scratched up after polishing, go back a step or two). I spent two days on this because this is my first time trying to fix clear parts, and the result is absolutely not perfect, but I've now got a pair of rear windows I can use. Unfortunately the right one had a stress mark too deep to fix and it also doesn't completely fit in the frame so I had to cut the top off. It will be cold in the winter, but I'm sure the tiny people inside will appreciate it in the summer.

Forgot the before photo. This is after 600:


Left: 2000, Right: toothpaste.


Rear windows on the left, original front window on the right.

[Wombii]

Trust nothing, test everything, and even if you tested it, something will ruin your day anyway. A pen I used to draw up the door panel lines is now bleeding into the final coat of glossy clear. Even the red Tamiya paint is bleeding a bit because I went way too heavy on the clear trying to get a smooth finish.


To be clear for the accident report: The pen lines are bleeding because I didn't test it with the clear coat. The red is bleeding because I significantly overdosed it with solvents from the clear coat.

[Wombii]

Looks like the ink floated to the top of the clear coat, so most of it could be removed with light sanding. The red paint is deeper, so I might have to live with that small flaw.

Mirror mounted reverse lights (?)
Warm white 3528 LED glued to transparent plastic inserted into a 6.3mm outside width square styrene tube. Inside filled with more glue and a 2mm thick piece of styrene glued to the back. Mounted to the mirror with a piece of a paper clip. The wires are harvested from a broken HDMI cable. They're very thin, feels like about half the size of the 28awg wire I've used for the other lights, and I'm not sure if I'll be able to crimp connectors to them.

[egronvold]

The level of detail and patience...

[Wombii]

My patience got tested today when I had wired everything up and mounted the cab and then realized I had to disassemble everything again because I crossed the connectors for the cab dome lights

Milestone: All cab lights wired up for the first time.

Connections for cab dome lights and visor lights.




Sure, I could cut the wires shorter, but then I wouldn't actually be able to get my hand in under the cab to connect them.


It works! Does it look okay with the rear side window rolled down a bit? Should I cut it down lower?

[egronvold]

Looking good! Wait with the cut until you have place the «people» inside. Then you can better decide.

[Wombii]

You're right. If I find or make some good looking people, I might want one of them to lean an elbow on the window, so I could cut it a bit more then.

Minor update.
Did a very rough trimming of the inner rear rims and painted them black so they look more like brake drums.