Arnold rapido 4-6-2 boiler

[draskouasshat]

So I'm looking at another Santa fe project. After lookng at the boiler profiles of this old model, I've decided that I need a few of them to chip up. Does anyone on here happen to have one in the parts bin they'd like to let go? If like 5 or 6 of the boilers.

Thank you

Adam Draskovich

[UP4-8-8-4]

You are aware that the Arnold Rapido 4-6-2 as well as their 4-6-4 are metal boilers ?

[SkipGear]

Very unfriendly to kitbash.

[draskouasshat]

Yes, I know this information but they have the right profile for what I need. The other Pacific boilers have a more gradual transitions between the sand and steam domes compared to this boiler.

[SkipGear]

If I remember, it is also quite long for a Pacific. I have a couple of them floating around someplace and they were very out of scale for any other mechanism I played around with. I might make a good heavy if you shortened it by a couple scale feet.

[draskouasshat]

If you have one, could you grab some diameter measurements for me? The plan if to shorten it to turn into this. Notice the short acute transition netted the steam and sand domes.

Adam Draskovich [ Guests cannot view attachments ]

[Cajonpassfan]

Sorry Adam, I dont mean to rain on your parade, but I think you will find the Rapido Pacific/Hudson boiler way too huge. I'm traveling now so I can't check the dimensions, but I do know the 1200/1300 class pre-WWI ATSF Pacifics were quite light. A while back I recall looking at a light USRA boiler as a starting point and it was a bit oversized...
Otto K.

[draskouasshat]

Sorry Adam, I dont mean to rain on your parade, but I think you will find the Rapido Pacific/Hudson boiler way too huge. I'm traveling now so I can't check the dimensions, but I do know the 1200/1300 class pre-WWI ATSF Pacifics were quite light. A while back I recall looking at a light USRA boiler as a starting point and it was a bit oversized...
Otto K.

Thank you Otto. I was figuring that would be the case but wanted to get my hands on one to see. I think the Bachmann light mountain might be small enough and possibly the old atlas light Pacific but they don't have that sharp conical transition that's distinctive to the boilers on them. Hmmmmmm. Where to look now?!?!?!

Adam Draskovich

[SkipGear]

Finally dug one up. The taper angle is exactly the same as the MP Pacific boiler, it's just the smoke box section is larger diameter so the taper is shorter. It is probably much too large for what you want to build.

Smoke box diameter: .515" (no lagging)
Course in front of taper: .537"
Boiler behind taper: .632"

Over all length (front of cab to front of smoke box}: 2.975"
Cab to taper: 1.384"
Taper: .490"

[draskouasshat]

Awesome info Tony! Thank you very much! I guess I'm back to the old atlas light Pacific boiler. Now who has a few of those they want to get rid of?

Adam Draskovich

[mmagliaro]

Awesome info Tony! Thank you very much! I guess I'm back to the old atlas light Pacific boiler. Now who has a few of those they want to get rid of?

Adam Draskovich

Send me a PM or email so I don't forget and I'll go hunt for them in my stash.

[randgust]

There is a point on such projects where you have to ask yourself two questions.....

1)  Is the departure from the ideal proportions sufficient to justify the effort and $$$ involved to hit it?   There's a lot of issues with that locomotive that make it look 'right', but boiler proportions don't necessarily hit my top 5 issues with it.   What I find objectionable on the MP 4-6-2 painted up that way is what happened to the skirts around the running boards.   THAT I think is a critical foobie, then on to the tender...trailing truck...on and on and on.

2)  If you do decide that it's worth it - grinding down any boiler (plastic or metal) and 'starting over' should be compared to just getting the dimensions and making it right - using K&S tubing as the base and making the transition section from automobile body putty.  At what point is is really easier just to start with raw brass tubing that you can get EXACTLY the dimensions you want?

I've made several smaller boilers from brass tube and have come to the conclusion that's the way to go - I'll still hack up other boilers, but it is to get the domes and other details I need.   I've also looked at a bunch of N scale 4-6-2's trying to do #1316 (Texas State Railroad 500, currently in pieces) and have the basic dimensions from "Iron Horses of the Santa Fe Trail", and I'll agree..... nothing out there is quite right.  Close, but no cigar.  I really like the structural rigidity and weight of brass tube, and how easy it is to work with it.

[Spades]

http://model-railroad-hobbyist.com/magazine/mrh-2012-06-jun/steam-loco-styrene_p1 always wanted to try this. 

[draskouasshat]

Max, I'll be emailing you shortly!

Randy, this might be the next step if I can achieve the correct boiler dimensions. I tried the brass tube ages ago but didn't have good results as my modeling wasn't quite there yet. After the turtle back out of mdf, I might venture down that road again.

Spades, very good article! Thank you for posting that!

[draskouasshat]

Thanks to max, I've got a couple more shells to play with. I have learned something new though, I need the old atlas light mikado boilers, not the pacific.  The mikado has the short transition between diameters unlike the pacific so if anyone had any of these they'd like to get rid of, I'd like to pick up a couple more.