Repowering a Doodlebug (Bachmann)

[up1950s]

Ever think about a Kato RDC as the bones of the build ?

[randgust]

Not really, when I already had a TM20 just lying around.   I'd bought one to see what I could do with the trucks for another project and it wouldn't work so it was an orphan anyway.

I think the RDC trucks are a completely different animal in terms of size, wheelbase and appearance even if the drive is very good.   And I doubt you could tweak the truck centers this easily.  This measures out on truck centers to 54' 6" and that front truck is way forward, all the way to the front wall of the motorman.  Budd is 59' 6".   If there's a plastic frame on the truck ends it might be shortened.
https://www.katousa.com/cgi-bin/dl/dl.pl?dl.mif,N-parts-rdc.pdf
I've never had one to tear apart so I'm not sure how well it would work, but the trucks also have an 8' 6" wheelbase.
Kicker for me is that the TM23 chassis (which looks identical to the TM20, 12mm trucks, inside wheel pickups) is only $25.

PS, if anybody wants the bones of the old Bachamann chassis - motor, trucks, wheels, raw frame, no steps, underbody detail, or truck sideframes - you might still have a usable gear in there or two - for postage only, PM me.  No reason for me to keep it.

[randgust]

OK, this shows the stretch of the driveshaft.  The Tomytec shaft fits in a K&S 3/32 brass tube.  The center extension is 1/16 K&S brass tube, which also fits inside the 3/32.   It's just all ACC'd together and is very solid.  I put it in place and slide the sleves, and just hit it with the ACC when I get the length right.  This works with all tweaks of the Tomytec drives, whether you are making them shorter or longer.  This plus the plastic frame is why they are so incredibly versatile for applications like this.





These shots also show that I managed to glue on the steps and the rear coupler from the Bachmann.  Tomytec has a couple 'fillers' provided for the end frames that were just the right thickness and just snap on, glue steps and couplers to that.  No photos yet, but all the glass is cut and refitted, and I'm working on putting a golden-white LED inside the headlight casting instead of the original big honking LED that Bachmann did.

[SandyEggoJake]

Loving this build. 
How does ride height compare?  Comparing to my Bmanns, looks about the same, which I always thought was high for the Santa Fe propotypes. 

EDIT: looking as some other prototypes, now realized how tall these actually were.   Seems my Santa Fe prototype includes a bit of a skirt- that extends to the middle rung on the ladder - that accounts for the different appearance. 

[up1950s]

You got me thinking easy chassis for a Sperry Fantasy Rail Car . I think decals are available . Very few now what each number looks like including me . Pick a number they didn't use a screw the critics .
Randy the seed sower is at it again . This hobby is about fun and Proto Perfect is too stressful for me .

[SandyEggoJake]

Agreed!  The long talked about Sperry self propelled track cleaner was exactly what I was thinking. 

Some time back I spoke to John Claudino about taking his Aztec cleaning concept and milling a chassis to fit the Bmann shell.  He was kind enough to even send me one of his chassis to better understand the geometry, but he passed on the project as he share with me his concerns with car centered roller issues on curves.   Of course, this solution would be just a 4 wheel drive Sperry.  But using Randy's solution, one might do great for an 8 powered wheel pad type track cleaner. 

(Never understood the stress some feel with "proto perfect".  We agree the hobby is about fun... I'm just one of those pin heads who enjoys the research and pushing the technical limits to progress the level of realism.  For me, more real = more fun.  But I get the toy side too.)

[randgust]

Finished photos shortly and I'll probably do a video for YouTube.   I'm happy with it.  I was finally satisfied when I pulled the traction tire wheels and substituted solid wheels, that made more of a pickup difference than I originally imagined.

I'm using that PRR diagram to decide if my ride height is valid, from the sills down I'm OK and I got the frame to inset into the body about 9" by removing the window inserts below the window glass.  If you think that is still too high you could cut down the plastic frame sill edges (which I was going to do until I put it all back together).  I decided I didn't need to do that.

If you wanted to make this into a track cleaner, there's a lot of room in there for a whole lot of lead.   If you left one traction tire axle on it it could be a stump puller, my powered boxcars full of lead do 25-30 cars by themselves with the traction tire on them.

I'm a real fan of these frames.  If you haven't ever messed with Tomytec frames, they've got about four truck designs over two revisions:

14mm truck axle centers, offset gear tower, end-axle pickups
14mm truck axle centers, centered gear tower, end-axle pickups ("R" versions)
12mm truck axle centers, inside axle pickups, offset gear tower (which is this one for the doodlebug)
12mm truck axle centers, centered gear tower (R versions)

Now take those four basic truck designs and put them in different length frames and give each one a different model #, which becomes way more complicated than it has to be.   Frames are all plastic, the only differences tend to be on pickups lengths and the truck sideframes packaged with each one.   The original versions pivoted the truck on the universal socket so they could turn around in their own length.   The "R" versions pivot the truck on the worm and the universal swings out, I'm not a big fan of that design.   That's pretty much how it works.   It's a very basic, and flexible design, yet has all the pickup and gearing features of some of the best.   The very short ones like the TM03 only have one powered truck, the longer ones have two powered trucks.   The entire design is hackable and you can change motors, frame lengths, etc. very easily.    I've made my own frames for the Whitcomb switcher and the powered boxcar kits and the only real tweaks are to splice the driveshaft length and pickup strip length like I did here.   And the truck/gear/pickup design quality is just excellent, right up there with Kato.  The motors appear to be the same as used by Bachmann in some of the bigger locomotives.    I've substituted Atlas motors in the powered boxcars if I needed a slower RPM.

So while there's other chassis that might work, you can pretty much figure that you can do whatever you need to with these in terms of truck centers, and you have a 'short' and 'long' wheelbase truck to work with.   I get all mine from Plaza Japan, but even Walthers finally caught on to them a year or so ago.     Plaza Japan has descriptions that include a drawing diagram of the models so you can figure out the truck design, wheelbase, frame length, etc. because Tomytec keeps adding and subtracting model numbers on a regular basis and the availability changes - even though what you really need is to just check out what trucks the darn thing has, never mind the frame length (too long better than too short, by the way).    I'd recommend going to the Plaza Japan ebay store, searching for "Tomytec chassis" and looking at the images - they have the frame diagram on every one of them so you can figure it out.

Tomytec has had no US distributors in the past, then Walthers, and the boxes are almost entirely Japanese.  I've even made an attempt to buy wholesale, and communication with them is near impossible, so I've resigned myself to the fact that the Japanese dealers do a pretty decent job of stocking them and prices are reasonable.   Only the ship time leaves you wondering.  I see that Walthers now shows 'out of stock' on almost everything but Plaza has most everything.

 

[mandealco]

Nice job Randy.  Far better than my repowering of a Con-Cor RDC many years ago (way too many to remember).  I used a Con-Cor U-50 chassis with the centre trucks removed.  Had some internal clearance problems to solve for memory, but it worked.  However, I would never do it again, have you seen how much U-50s sell for these days!
Cheers
Steve

[randgust]

OK, final build shots.   Yeah, I know, it's a PRR car arriving in Flagstaff, AZ, deal with it because the PRR modules are in storage.

But the point is that by the time I've done, you'd be hard pressed to tell I changed anything here under the hood, and I think it rides a bit lower.





There's more that I could do, but after what...eight years?...it finally got some attention and is actually runnable.

[Simon D.]

Possibly too late, and maybe not the right ones, but Dirk from ATSFscalemodels is doing ATSF doodlebug truck frames on Shapeways: https://www.shapeways.com/product/S2TEYBQ27/atsf-doodlebug-truck-sideframes-36-quot-2-33-quot-2?optionId=62535043

[randgust]

It's the right bug on the wrong layout.   I'm an ATSF fan of the '70's and a local (PA) steam fan of the 20's, which is where the bug fits in to my logging layouts connecting to PRR.   While the ATSF Belen-El Paso route had one, there weren't any in Arizona I'm aware of.

ATSF's doodlebugs did have that weird feature of the longer passenger car truck wheelbase on the back.   You could easily do that with Tomytec though, as the 12mm and 14mm truck wheelbases both have the same sized frame hole mount and the same universal shaft.

In the late 20's this PA-NY region was just thick with doodlebugs.  My local run (Oil City PA to Olean NY) only lasted one year and was replaced by a 4-4-0 up until discontinuance 10 years later.  But other local lines - NYC Dunkirk-Titusville, Erie Salamanca-Dunkirk, Erie local on the main line, PRR Olean-Rochester, PRR Olean-Bradford, were all doodlebug routes until the depression shut down many locals entirely.   The only two that stayed steam were mine, and the Jamestown-Buffalo Erie run, which was a K1 Pacific with 2-3 cars.   The only thing I can figure is that I know the Jamestown-Buffalo Erie one had a tough hill southbound at Gowanda, and my PRR run was a sustained uphill river grade the entire route.   I think, but don't know, that these early doodlebugs had some real issues with hills, or overheating, or keeping schedule speed, or something.   You never seem to see these in any area that had many grades to climb.  Which is also nearly everywhere in Arizona on ATSF  - longest sustained mainline grade of like 500 miles from Riordan to Needles.   Meanwhile, they were on a lot of the flatland Kansas locals.   But even the dinky branchline trains in Arizona (Williams-Grand Canyon and Williams-Phoenix) were a diesel and 1-2 cars to the end.    And trailers?  Other than ATSF dragging around a conventional streamline car, I think they were a lot rarer than you think.   I've never seen any local shots pulling anything.

[randgust]

Here's the video:

[up1950s]

Cool , you have plenty of room to add a flywheel of you want big time coast too .

[brokemoto]

And trailers?  Other than ATSF dragging around a conventional streamline car, I think they were a lot rarer than you think.   I've never seen any local shots pulling anything.

Crabgrass and Weeds, Louie, Ma and Pa all had doodlebugs' pulling trailer cars.  Usually, it was head end cars.  B&O ran into Springfield, Illinois and Frederick, Maryland with doodlebugs' pulling a baggage car.

The RDC was really the Ultimate Doodlebug, but if you pulled anything with it, you voided the warranty.  This did not stop the Louie.  The Louie ended up selling their two RDC-4s protobashed to carry passengers to the C&O.

The funniest looking photograph of this that I ever saw was one of a CRI&P RDC-1 in Kansas as it pulled a boat tailed observation that had been turned into a baggage/passenger combine.  Guess on which end the baggage door went.   Of course, it made sense to put the baggage door on that end, as there was the possibility of only one passenger door on a boat tailed observation.  For that reason, the baggage door could go only on the observation end.   

CRI&P had all sorts of basher's dream equipment and ran a number of modeller's dream trains.

[randgust]

Oh, I just had to look that one up because I couldn't imagine what that would look like.   Holy CRIP...

http://rrpicturearchives.net/showPicture.aspx?id=3227119

And yeah, they towed it around with an RDC.