Mine by far was a used Kato/Atlas n scale GP7.
It took a lot of milling to get a dz125 decoder in it but it dosent seem to have lost much of its pulling power.
Let everyone know what is by far the most difficult to install.
For me, it was putting a Tsunami into a Proto GP9. The decoder itself was too thick for the space above the motor where I'd had the original DH123, and then there was the matter of the speaker.
I slowly cut away chunks of metal, both for the decoder on top and the speaker in the crew compartment gap. I ended up fabricating my own baffle box out of styrene to reduce the amount of weight I had to cut away. I worked slowly, a bit each day for a couple of weeks.
Of course, when I did this, I figured I might as well weather the engine while I had the shell off, so I had to pull the truck sides and weather them, too. One thing leads to another, so I had to weather the other non-sound Geep that this one will be MU'd with. But, after the whole project was complete and both engines were back in service, I was a happy camper.
The easiest? A Proto S1. I'd put a DH123 in myself, but I wanted sound, and I couldn't imagine putting it in. So, I brought it to my LHS and said, "Make it so."
It takes an iron man to play with a toy iron horse.
Mine would have to be a sound install in the tender of a Kato N scale Mikado. Owing to the size of the sound decoder (Soundtraxx DSD-90, medium steam), I had to remove the clip that held in the power collection wires, which in turn meant that the tender trucks had to be hard-wired to the decoder, which involved modifying the shell to clear the wires. Also needed to modify the shell to accommodate the speaker.
Then there was the wiring done within the actual loco boiler, routing the wires so they wouldn't foul the trailing truck, etc. But it was a fun challenge, in a way.
The Location: Forests of the Pacific Northwest, OregonThe Year: 1948The Scale: On30The Blog: http://bvlcorr.tumblr.com
I've done a few so far...let's see...a Con-Cor Veranda Turbine(traction+LED headlamp),a Rivarrossi 4-6-6-4 Challenger(traction+LED headlamp) and a Spectrum DD40AX(traction only),all in N scale.While the Veranda was fairly easy,the Challenger needed some milling of the frame for wire passages.The toughest was the Centennial as heavier milling has been necessary to allow for the extra wiring for the twin motors and special care was required to be sure they'd be properly isolated from the frame.
Atlas N scale Shay
That is tough, but is would have to be one of the following:
Back in 1985 the smallest decoder available was 1" x 2.5" x 5/16" thick. Some decoders today are smaller than the power transistors were back then. Anyway, I put one into the new Atlas HO scale RS-3 without removing any of the weights. I had to cut the decoder into three parts, put jumper wires where the traces had been cut. There were three IC chips on the board and I stuck one under each cab window and the third glued to the roof. I hung the 4 power transistors off the stock plastic board over the motor. They were carefully placed next to the drive shafts coming off the motor. I often thought it would be way cool to replace one of the fly wheels with a fan to cool them, but never got back to that idea. The driving transistors were put on the top of the plastic board replacing the original light and fiber optics. I replaced the fiber optics with PFM 1.5mm microbulbs (which were also fairly new technology at the time). It took me about 20 hours to do that job.
The second choice could be a brass HOn3 2-8-0 C-16. I was dealing with a slightly larger of decoder than above because it also had sound. It was about 1.5" x 3.5" x 5/16". Even though I had a tender to work with (a bit larger than an N-scale 50' box car) the speaker consumed most of that space. Also note that back then there were no nice 1/2", 3/4", or even 1" speakers. The smallest speaker I could find was 2" so I had to cut the brass speaker frame and cone to fit. When cutting the decoder up into pieces there were many more traces that had to be jumped. There were also the cam wires used to synchronize the exhaust sound. I think I had 5 wires running from engine to tender. The worst part though had to be the "hot"-to-rail brass body and making certain nothing touched it. No headlight or marker lamps, I wimped out and used jewels.
Everything since 1994 has been a walk in the park by comparison. Truly modern stuff (decoders that replace the original circuit boards) almost isn't worth calling an "installation".
You guys that do N-scale have my utmost respect.
Friend of mine scratchbuilds N scale steamers, SMALL turn of the 20th century N scale steamers. ANd manages to fit a decoder AND the motor in a small tender - the boiler is too small for a motor. He uses the ultimate micro decoders for Z scale, with maybe 1/4" of wire - really don't know how he does it, but they work.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Us HO scalers have it easy. Even a totally non-dcc friendly loco can be done with relative ease. The most difficult that I have done recently was an older Bachmann split frame loco. It became the subject of a published installation on the TCS web site
http://www.tcsdcc.com/Customer_Content/Installation_Pictures/HO_Scale/Bachmann/Spectrum_Dash_8-40CW/Spectrum%20Dash%208-40CW.html
Other than that, I would have to say fitting a Tsunami into the tender of a Rivarossi Big Boy. The installation itself was not too bad, but getting the tender apart was a bear.
Simon Modelling CB&Q and Wabash See my slowly evolving layout on my picturetrail site http://www.picturetrail.com/simontrains and our videos at http://www.youtube.com/user/MrCrispybake?feature=mhum
For HO scale (I won't touch N) it had to be an original Bachmann standard line Southern Pacific 4-8-4 Northern with the split frame and smoke generator.
The motor was mounted between the frame halves. The side rods all had to be removed in order to get the frame apart. The frame had to be milled out to fit the decoder.
Since I didn't want to get blamed for breaking something, I had the owner perform all of the side rod removal and frame disassembly. I installed a motor-only decoder for him and reassembled the frame. I don't think he has attempted to reinstall the side rods, even though the decoder was installed over two years ago, because he lost some of the screws.
For me it was a brass CP Jubilee. I just wanted to throw it out the window. Tsunami & sound...... I couldn't get it to keep contact and it kept re-setting!
Ihc mother hubbard in ho scale. So tough that I haven't even been able to get the derned thing opened up yet.
alco's forever!!!!! Majoring in HO scale Minorig in O scale:)
These are N-scale.
I would say that the most challenging for me is a TCS CN-GP decoder in an old (1992) GP30. I had to file some of the frame down and solder in the motor contacts. It was not that difficult but originally I had pinched the motor wires between the frame halves causing problems. The fix was to cut a groove with a file ot motor tool. Once the decoder was in and the frames were screwed back together all I had to do was solder the three wires that connected the 2 piece decoder. Although a bit frastrating with the pinched motor wires I would recomend it.
Another one that I thought should have bean much easier is the decoders for my F3 InterMOuntain A & B units. They do not come with lights so I had to obtain the correct light(LED) insulate the area and solder it to the board for the A unit. In looking back it was not that big a deal, just unexpected.
John
N-scale is too small for me......I have a tough time in HO! but my toughest was a bachman 3 truck shay.
DANSGRANDPAPAN-scale is too small for me......I have a tough time in HO! but my toughest was a bachman 3 truck shay.
Ditto
The speaker that I got with the decoder was bigger than the tender. Had a heck of a time getting the baffle to seal so that I get sound to be audible. This is back before the Tsunami's came around. Turned out the problem was the hole that I had to drill for speaker wires. It worked really well once I sealed that with a little silicone caulk.
Colorado Front Range Railroad: http://www.coloradofrontrangerr.com/
Actually installing a TSU-750 in an already sound equipped Athearn N scale Challenger...Should be a piece of cake...get the tender open,remove the MRC printed board and then link the Tsunami to the existing wires.That easy it SHOULD be but behold...Granted,the room is sufficient but you have to remove the center pillar that used to hold the original decoder and the original weights(no big deal) to allow for the TSU.Then comes fabricating the speaker holder (for Soundtraxx 3/8 in.) that will also accomodate the decoder.The catch...the original wires to the MRC junk are so short that you need tweezers to twist them,good thing the TSU's wires are quite long though.The second catch is that the MRC decoder controlled the headlamp through only one wire,the other path being handled through a printed board (inside the loco)to the wheels so I'll probably have to run an(or two) extra wire(s) along the motor to the headlamp to bypass this circuit and have the TSU wired correctly.I haven't figured that part yet...It's not that difficult but in no mean as easy as one could expect.
for me it was the N gauge Tomix 'James' from the Thomas the Tank range.