Against all good advice - bought a junker Jamco

[nickelplate759]

51" in N scale is darned close to 28" in HO.  You might repurpose some HO wheels - maybe from NWSL?

[nkalanaga]

Somebody a while back used HOn3 wheels under an old Arnold/Rapido diesel, and they worked fine for N, so I'll second George's suggestion.

[nickelplate759]

Somebody a while back used HOn3 wheels under an old Arnold/Rapido diesel, and they worked fine for N, so I'll second George's suggestion.

3

That was me 

[nkalanaga]

Then you don't need a second, do you?  You KNOW it will work!

[randgust]

Working backwards into issues, what I really want to do is get the tender attached for testing, to do that I need to redo the drawbar, and to redo the drawbar I've go to know the right distances as you really want that tender as close to the cab as humanly possible.  That's always the dumbest and ugliest thing about N steam is that chasm between the two.   But that also means I have to know exactly where the cab ends up, and I already found out the brass cab is a foot too long and at least in my opinion, doesn't look right.

So I got the Shapeways cab, which looked pretty good in the design, but arrived with huge printing flaws.  The sides of the cab were so vertically striated that it looked exactly like wood siding with slots inbetween.   That's not in the design, there's not even lines there.   I discussed it with the designer just to make sure, not his fault.  His design shows the right rivet lines, too, but they didn't show up in the print resolution.

So....I decided to file the cab sides flat below the windows and re-sheath the sides with .005 styrene and have a do-over.    I held the styrene on with ACC so it didn't warp, filed the edges flush, and then added the cab armrests and the 'right' rivet lines by looking at photos (Archer rivets).

The sides of that cab should look dead smooth, but you can still see the rivet lines in almost every photo.   Which makes me realize I'm closer to being an actual N scale rivet counter than I ever confess to be.

So here's what I ended up with:



That Shapeways cab has front windows and detail, too, where the Jamco is a solid sheet of brass.  It may not be perfect, but it's darn close

That's propped up with the old brass cab wrapper that I successfully removed from the boiler for comparison.  And I have to modify the rear mounting bracket for the boiler to take it up a foot shorter, as planned.    That work resulted in the smokebox front completely falling off the boiler, with the handrails, just as well because I wanted to add a headlight and also get rid of those chunky looking handrail wires.   And with those out of the way, and the cab out of the way...well, it looks rather practical to grind off a lot of the cast-on piping.   Looking at photos, this thing is just COVERED with piping detail, only a matter of how much you want to add here.  The boiler is actually cast brass, and hard.  Not easy to drill, we'll see.

I'm looking forward to having to figure out the drawbar here, as it wants to be a visual block between the cab/firebox bottom and the trailing truck, on the 3400's you certainly can't see any daylight in there, the frame extends behind the trailing truck frames up to under the cab.  It's a mass of frame, piping and detail, none of which is on the Jamco.   

I did get this book, and highly recommend it to anybody attempting this at home.  Each individual loco is supplied, and nice clear B&W images showing both sides and all the variations in the classes on wheels, tenders, rebuilds, etc.:
https://images-na.ssl-images-amazon.com/images/I/41yw%2BiPpzzL._SY284_BO1,204,203,200_.jpg
When you really study the locomotive, you realize the similarity between this class of heavy 4-6-2 and the 3700-class 4-8-4's.  The book says they could even share siderods, so my observation that the Bachmann Northern crosshead guide assembly seemed to be nearly identical to this in dimensions was no accident.   These are a HEAVY Pacific by any definition.

By the time I'm done here, the frame/chassis and the basic boiler casting may be the only original parts!

[superchief]

Great job Randy,
     I have one of these as well, but it will always be a shelf queen, history of N scale. I like what you are doing with the engine, good luck and I will keep watching.
                                                                                                              Gordon Bliss

[mmagliaro]

I think the cab looks terrific.  I'm really enjoying this project.

About drilling that hard brass boiler for piping details... what brand of wire drills are you using?
If you are able to hunt down some new-old-stock American-made ones from "Precision Twist Drill", "Cleveland" or one of those other old grand brands from decades gone by, you will find that they drill through metals far easier than
any of the "hobby" bits we get these days.  (You can also buy new Precision Twist brand, but they are really expensive).
The old-stock ones can sometimes be had for $1 per bit, so figure $12 for 12 #80's (they break, so of course, we always hoard #80's)

When I discovered how much better these bits were, I abandoned buying wire drills in the hobby stores forever.

[randgust]

Well, Max, we'll see.   I've learned that for the smaller drills (.020 and smaller) that putting them in a pin vise is an invitation to failure and snapping a seized bit off in the hole.  I'm much more consistent putting them in the Dremel on the lowest speed it will still turn without stalling, center punching the hole, liberally lubricating the bit with #108, and literally putting my finger lightly on the drill shaft as I'm working it in at such low RPM to stabilize it and pull it back if it starts to overheat.   Pull chips often, don't push your luck.  Cross fingers.  And I'll still snap a bit now and then.   Oh, and always, always, always have eye protection.   I've had a number of tiny bits shatter, pulled a shard out of my ample forehead once....

But I'll still test drill this boiler casting in a couple of places that doesn't show first just to see how it goes.  And before I grind off the other piping.....

[mmagliaro]

Well, Max, we'll see.   I've learned that for the smaller drills (.020 and smaller) that putting them in a pin vise is an invitation to failure and snapping a seized bit off in the hole.  I'm much more consistent putting them in the Dremel on the lowest speed it will still turn without stalling, center punching the hole, liberally lubricating the bit with #108, and literally putting my finger lightly on the drill shaft as I'm working it in at such low RPM to stabilize it and pull it back if it starts to overheat.   Pull chips often, don't push your luck.  Cross fingers.  And I'll still snap a bit now and then.   Oh, and always, always, always have eye protection.   I've had a number of tiny bits shatter, pulled a shard out of my ample forehead once....

But I'll still test drill this boiler casting in a couple of places that doesn't show first just to see how it goes.  And before I grind off the other piping.....

Funny, I am just the opposite.  I cannot hold a spinning Dremel nearly steady enough to keep a #80 bit from wandering or breaking  off.  I like to twirl the point of a #11 Xacto blade right into the spot where I want the hole, so it makes a little guide dimple.  That does tend to wear down or break points off of #11 blades, but oh well.  Broken Xacto blades are just a cost of being a model railroader to me.  I buy them by the 100 pack for that reason. 

With the dimple,  the small bit doesn't wander.  I only let about 1/16" of the small bits protrude from the pin vise chuck so they don't break.  Like you, I do put a drop of oil on the bit and keep pulling it out to clear chips often.  If the hole has to go deeper, then once I get some of it drilled, I let more of the bit out of the chuck and continue on.

[strummer]

Funny, I am just the opposite.  I cannot hold a spinning Dremel nearly steady enough to keep a #80 bit from wandering or breaking  off.  I like to twirl the point of a #11 Xacto blade right into the spot where I want the hole, so it makes a little guide dimple.  That does tend to wear down or break points off of #11 blades, but oh well.  Broken Xacto blades are just a cost of being a model railroader to me.  I buy them by the 100 pack for that reason. 

With the dimple,  the small bit doesn't wander.  I only let about 1/16" of the small bits protrude from the pin vise chuck so they don't break.  Like you, I do put a drop of oil on the bit and keep pulling it out to clear chips often.  If the hole has to go deeper, then once I get some of it drilled, I let more of the bit out of the chuck and continue on.

Wow Max, that's what I do as well.

Knowing I use the same technique as the "Master Builder of N Scale" makes me feel better about myself... 

Mark (also) in Oregon

[johnb]

This is one of my favorite threads on here and I am constantly looking for updates

[randgust]

I'm having fun with this because it's pure frosting, not a strategic project, just something I always wanted.   And it's certainly evolving as I hit problems and opportunities.   I had no idea that new replacement tender would be that good.   And while I THINK I can put a lot more detail on that brass boiler casting, I have yet to actually try drilling or grinding old detail off of it.   I don't have the time to work on this one as much as I want.

I still have the Kato five-pole motor, flywheel, shaft and universal laid out, but was really surprised how good the stock motor worked.

I still want it as a runner though, not a contest model, so mechanism smoothness, pickup, and tractive effort matter for my 'display fleet' of bigger steam.   My GHQ L1 conversion fits that description, it's a great runner, pulls like a horse, and is absolutely dependable and not particularly fragile.   My internally-modified Hallmark 4-8-4 can just 'barely' squeak through my layout, it's just really too darn big and it's an adventure to have it pull a full train to see if it won't find some new area of track it now hates and end up on a heap on the floor.   My LL 2-8-4 is really kind of worthless although it looks great, to pull anything requires my powered express reefer paired with it.   I can have fun with N steam without being particularly dependent on it, that's where I'm at.   I learned a long time ago to develop a diesel roster that had a second-string in case something abruptly failed, pull it out, put in the second string, and keep running.

[randgust]

Had a 'Eureka!' moment with the drawbar.   I had three goals here:

1)  Change the 'pull' spot from high, under the motor, and leveraging back on the frame to a spot as close to the immediate back of the drive axles - and low - as possible.  I've done this on other steam, and the impact on tracking, pickup, and tractive effort was dramatic.
2)  Put as much 'mass' as possible on the drawbar; on the prototype it's packed solid as the frame extends back to the end of the cab
3)  Create a structure to add more detail to down the road.

And, the existing drawbar coupled the tender way too far back, the gap was awful.

The big discovery was that the mount for the trailing truck, and the gearbox cover, was a cylinder, and a 5/32 K&S brass tube would fit over it without interference.  That known, I could change that to the rotating pull point, secure it with the gearbox cover, and build out from that.

It took some real messing around with a square brass section, cutting stuff out of the way with an abrasive disk, but I think I got it.    I also put together the ATSFmodels tender floor and trucks to set the locomotive-to-tender distance precisely.  With a LONG drawbar, torqueing the cab around a curve does not pull the tender closer, distance remains constant.



From the bottom, you can also see that I pinned the connection, I'll trim this up later and put some thrust washers I there, but you can see how I held it on.



Note the cutout I had to make for the trailing truck axle.

After temporarily attaching the tender deck, I could finally run the darn thing around without a 'IV cord' wire, even as an overgrown 0-6-0 without a cab.  It runs pretty well, so far so good, the running gear is pretty much flawless.

The screw that held on the rear bracket to the frame had to go.   There just wasn't any vertical clearance for the new drawbar with that there.  I ended up soldering that bracket solid to the frame and relocating the screws under the cab as the position of those screws changed anyway when I lowered the entire back of the locomotive by a foot.

[mmagliaro]

Totally digging this!

And what a great observation.  The longer the drawbar is, the less the distance between the cab and the tender will change in a curve.  I had never thought of that, but of course!  The longer it is, the more it approximates a straight line even when the engine is on a curve, so the less it changes.  That's a great tip to put in the back of my brain for future loco projects.

[peteski]

Totally digging this!

And what a great observation.  The longer the drawbar is, the less the distance between the cab and the tender will change in a curve.  I had never thought of that, but of course!  The longer it is, the more it approximates a straight line even when the engine is on a curve, so the less it changes.  That's a great tip to put in the back of my brain for future loco projects.

Interesting.
Kato's GS-4, and FEF3  (and IIRC, Mikado) also have long drawbars attached to the loco low and behind the rear driver.