Scania airport fire truck

[Wombii]

Some clips from the first test of the roof monitor and pump mounted on the truck. Seems to be sucking air somewhere, possibly the filter on the supply side. Nozzle also needs some work.
The pump is currently drinking about 2.5 liters per minute.
https://www.youtube.com/watch?v=fGMQzeoWdYY

edit: if you're as easily entertained by flashing lights as I am, here's a minute of flashing blue lights:
https://www.youtube.com/watch?v=q4rnpqTKm18

[egronvold]

Happy to see you’re ready for the last part of the fire season

[skeeter]

Hopefully it's an easy fix getting the air leak repaired, & we can see some RC fire fighting action videos soon.

[Wombii]

Working on the water tank. It's made from 1mm styrene and comfortably holds about a half gallon / 2 liters of water. The bottom is sloped to help the last bits of water find its way to the pump.



I want a large opening for maintenance access. Using a 2mm plate for the lid. I hope I'll be able to make it somewhat water tight.



The water level sensor drops down through a hole in the top. 5 wires connected directly to an arduino with its pins configured as INPUT_PULLUP. When the water reaches a powered sense wire a connection is made to ground and the arduino does whatever it needs to do.





Here it is in the truck. The plan is to add another tube to the top that will let air in and out, and a tube somewhere for the fill/drain pump.



Video of sensor, tank level lights and telemetry:
https://www.youtube.com/watch?v=VphOW5oXx9A

[Wombii]

Got the red stripe painted and have started test printing some decals.

[kaptain Jack]

How do you print decals?
Tnx

[Wombii]

Sorry, I should have been more precise. I've just printed them on normal paper after making and scaling them with photoshop and illustrator. When I'm happy with them my plan is to either use printable water slide decal paper at home or have someone cut them out of vinyl for me. I have two local companies that does signs and car graphics, so I can check with them how small they can make the details.

[skeeter]

Originally Posted by kaptain Jack

How do you print decals?
Tnx

I as well would LOVE to learn how to do this!

[Wombii]

The quote I got for making the decals was about 100$ more than I expected, so there's a chance I might have a go at making them myself.

Meanwhile:
Chest for the roof. Started by making a small table out of 2mm styrene, then wrapped it in Plastruct styrene tread plate. It doesn't open, but it's hollow so it can slide over the water tubing sticking out of the roof.




Started making the ladder. I was going to use precut strips for the sides and rod for the steps until I realised the total length of just the steps are more than 6 feet. Now I'm cutting strips out of 1mm styrene instead. The sides are 1x4x300mm + 2 pieces 1x2x300mm. Steps are 2 pieces of 1x3mm in 30, 36, 41, 36 mm lengths. Ladder itself is 3 elements and it rests on another element that is mounted to the roof and slides+tilts down to ground level.

[skeeter]

$100.oo for decals, OUCH!

100ft of plastic is a LOT too!

[Wombii]

Originally Posted by skeeter

$100.oo for decals, OUCH!

No, I said $100 *more*. It was actually close to $200 for a decal sheet around A4/letter size (large elements cut from black vinyl and small printed on clear vinyl).

I've just ordered 3 sheets of 20x25 cm size filled with text and logos printed on clear vinyl for $30 from stickerapp.com . I'll have to cut them out myself and I don't know how thick or invisible the clear vinyl is, but I'll make sure to update when I get them. Another alternative is printable waterslide decals, but I feel those need another layer of clear coat to protect them, and I don't want to risk messing up anything else right now.

[agriRC]

Skills here are incredible. Matching bodywork and curves like this is amazing!

[Wombii]

Thank you!

Ladder progress. I'm not sure how the pulley system works on the real one, so I don't know if I'll make it functional or just glue everything together.





I think I finally found the perfect water tubing for the monitor. 3mm ID, 5mm OD, 1mm wall thickness black silicone tubing. I tried 0.5mm wall thickness too, but that was way too thin and would kink at almost any bend radius. This one doesn't kink but is still very flexible and won't stress the servos.

[frizzen]

Glad to hear it works right, and the black monitor tubing looks good on there. What use was it originally intended to have?

It's come this far, got to make the extension ladder work...
I'm assuming ground ladders? Is that like a single 3-fly ladder with a support base, or a pair of 1-fly ladders?

[Wombii]

It's apparently nitro fuel tubing, although I've never seen anyone use black fuel line in an rc car, and I've never seen these dimensions. https://www.ebay.com/itm/401073783505

As far as I can tell, it's one ladder with 3 sections. Some kind of pulley system mounted to the side, a pair of spiked feet that digs into the ground and a pair of long support legs that can fold out from the sides. A short section is mounted to the truck and can tilt up. The final section seems to be mounted to the tilting bit and can slide out and down towards the ground. I think the ladder is then just strapped to this sliding section.

I'm having trouble finding reference material of it in use, but here's one image.(Image of aftermath of house fire, noone physically harmed)https://www.folkebladet.no/nyheter/a...leks%20Olsborg

Better image of the truck mounted section extended, and a video that I just now discovered of that part being retracted by a firefighter: https://www.sa.no/varteig/nyhet/matt...n/s/5-46-50230

[Wombii]

Finally found the ladder. Wibe NOR-BAS. Here's a spare parts pdf with good drawings of the ladder and pulley system. Maybe there's hope of figuring it out now.
http://www.wibeladders.no/globalasse...parts-list.pdf

Edit: and here's even a video demonstrating how to use it. I love how you can look for something for months on the internet with no luck, and then suddenly you find that golden clue and everything turns up.
https://m.youtube.com/watch?v=LrFnRqdL4rU

[Wombii]

Got started on the pulley system. Still not sure if it will actually work, as there will probably be too much friction in those tiny pieces. And I'm 99% certain that the rope actually passes through one of the steps to go from the right to the left side at one point, so I might have to simplify that.
It's also one of those fun situations again where I can't paint it until it's finished, but I can't disassemble it to paint it after it's done because of interlocking pieces.

[Wombii]

A lot of friction, but it's working!
https://youtu.be/u6E1-i7fYuM

The people who designed this ladder are a lot smarter than me. The pulley system for the bottom/middle section has a 2:1 reduction ratio with no loose rope ends. It starts attached to the lower left of the middle section, then loops through a pulley on the upper end of the bottom section, goes down to a pulley on step 2 of the middle section, through the step to the right side, through a pulley there and up to a pulley on the top of the bottom section. Then down to a double pulley on step one of the bottom section, up to a pulley on step 2 of the middle section and back down to the double pulley on step 1 of the bottom section before it ends attached to the middle section right side. Simple, right?

[frizzen]

Now it's back to the "how did he do that" level of awesome! The ladder reeving sounds like a headache to set up. I used a razor perpendicular to the work to adjust some sticking points on the FWD extension ladder, but it's much simpler...

If you say the ladder were to have been powder coated aluminum, it wouldn't need painted.

[Wombii]

Got the ladder smoothed out a bit, so it's actually not too bad now. Currently working on the part that's mounted to the roof.

Got the stickers from Stickerapp. I expected it to be printed in the US, but I'm not actually sure where they're from. I ordered them from the Scandinavian version of the web store (stickerapp.no). I got a shipping notification from USPS with a tracking number after a few days, but the tracking info only shows that a shipping label was made. Turns out that the very same day they actually arrived at my local post office in what seems like a Norwegian cardboard envelope with a different tracking number.

Quality seems very good. They're printed as a single large sticker on clear vinyl like the Tamiya decals. Neither my vernier caliper nor my digital caliper can tell a difference in thickness (0.1mm), but the Tamiya decals are much more stretchy and somehow feels thinner. The clear vinyl in the Tamiya decals are maybe a very tiny bit more clear, but it's on the order of 97% vs 99% transparency. Print quality is very good. Blacks look about 5% lighter than the Tamiya ones. Colors look like I expected. Most importantly, the size is pretty much exactly as ordered.

What I did to make them: I measured the size of the decals on the truck and on photos. I used Illustrator and made the text and numbers with the type tool, imported logos found on the internet, traced them if they weren't in vector format and modified them if they were not accurate (like adding "austria" to the Rosenbauer logo). I made the artboard 20x25 cm and added a thin border around everything to help mark the exact size. When I was happy with everything I used the stickerapp web store, selected a custom 20x25 size, imported the illustrator file and resized it so the border matched the template.

For info, 3 identical sheets cost me about 30 USD shipped.



Quality example: The smaller of the computer thingy is 14mm wide. The smallest visible text near the knife "BRANNTEKNIKK AS" is 0.7mm tall and looks good.


The Rosenbauer logo is from stickerapp. The Tamiya logo on the right is from the Tamiya decal sheet.


Tried cutting away the clear vinyl around the text.


Used a weak masking tape as transfer tape. This is my first time trying this.




Applied to the truck on the second attempt (Had to scrape off 3 letters very carefully and reattach to the tape after I accidentally touched it to the surface. It's almost straight!


Air force bird logo.