Best Of Bachmann n 44 ton sound installation project

[robwill84]

Ok, this is an idea thats been on my mind for a while, finally going to try it out. Some things still remain to be seen, but I'm about 90% sure its going to work, so here it goes:

Here is where my thoughts on the project started. The Loksound Micro Select sound decoder measures exactly (according to the manufacturer info) 10.6mm wide. The hood of the 44 tonner is a fraction of a millimeter less than 11mm. Obviously there is no room for the decoder with the stock hood sides and top, due to the thickness of the plastic. However, carefully cut out those parts and you have:




A tight fit, yeah? The stock top of the hood will have to go. I'll form a new hood, using the original plastic piece as a form, from .002 shim brass. Next, the top 1/3 or so of the stock hood sides will have to be thinned down as thin as I can get them. Height is not an issue. If need be, I can grind out as much as a millimeter or more of material from the frame, at a downward sloping angle from the motor. Length is fine, the decoder goes about halfway into the cab, leaving plenty of room inside the cab and in the other hood for additional weight and probably a few tantalum capacitors.




The next issue is the speaker. Obviously the stock weight below the motor will have to go. In its place I can fit a 15mm speaker in an aluminum sound enclosure. Clearance between the speaker enclosure and the trucks can be measured in fractions of a millimeter, but will be sufficient. One possible issue will be that the clearances are so tight that the speaker magnet is just barely attracted to the bottom motor magnet itself. I doubt this will have any noticable impact on the sound, but I will have to test it out.



So, that's where I am at so far. The next step is a big one, actually ordering the Loksound decoder with the 44 ton sound file installed. If anyone has any thoughts or observations, please let me know!

[garethashenden]

Have you considered either of the "cube" speakers made by Zimo? They have a 15x11z9 mm speaker and a 8x12x8 speaker. I haven't used either myself, but I've heard good things.

[robwill84]

Hi, thanks for the info. I had heard of the sugarcube speakers, but didn't know what sizes they came in. I'll file those away for another project, they're a little too tall to fit in here. The aluminum sound enclosure for the 15mm speaker is only 7mm tall. I'm hoping for satisfactory sound. My last project used a 16mm speaker in a similar enclosure:



That's in a Model Power Vanderbilt tender, using the oil bunker as a baffle. I was pleasantly surprised at the quality of the sound I got out of that arrangement:

and I even managed to get it finished, after a year of putting it off!

[peteski]

Couple of things:
Those ZIMO cube speakers are very good (for their size). I have a Fleischmann steamer with factory installed ZIMO decoder and it used one of those speakers.  It sounds great.  I just recently bought couple of those speakers from M.B. Klein.

Removing all the metal from the frame to install the electronics and the speaker will make this model quite a bit lighter.  That will most likely result in poorer electrical pickup and decreased pulling ability.  The pulling ability is not all that important for an industrial switched but poor electric pickup is not desired for sound decoders.

[robwill84]

Hi Peteski, yeah those sugarcube speakers look like a really high quality product. I'm definitely getting a couple for future use.

As far as weight goes, right now in stock form it weighs 35 grams. My goal is to exceed that by at least 10 grams. I plan to fill the cab with tungsten putty, and also use it around the rounded edges of the speaker enclosure where it won't interfere with the trucks. Then there is the whole other end of the hood. With the decoder removed there is room for a little more putty and I want to use at least a couple tantalum capacitors, I'm thinking I'll need at least a couple 100uf ones wired together to avoid excessive sound interruption. Or, I might not need any at all, as the majority of the Loksound decoder installs I have seen haven't used one.

[Chris333]

Nothing to add about the decoder. But lead would be heavier than tungsten powder in the cab.

[robwill84]

That's probably true, but I don't have any lead at the moment. I'm thinking that the putty will have the advantage of getting into every small space available, where it would be hard to cut and fit lead pieces.

[Chris333]

You can cut sheet lead with scissors and stack it up. Lead is easy to form as it is soft (just wash your hands when done    )

Density is measured in grams per cubic centimeter.
PURE Tungsten 19.25 g/cc
Lead 11.34 g/cc
Tungsten powder 11.25 g/cc (someone packed it as much as they could and only got 10.42 g/cc, poured in loose it was only 8.45 g/cc!)
Bismuth (Walthers LoTemp) 9.8 g/cc

You could also get 1/16" tungsten cubes for pine derbys. I believe they are tungsten alloy so they wouldn't be 19.25 g/cc, but probably more than lead.

BTW I had 90% tungsten weights made for my 44T, it is now 66 grams:
https://picasaweb.google.com/ErieChris333/NScale#5353981070035805282
The cab is still wide open. I know my example doesn't help since you will be fitting all that equipment in the same space. But I wanted to let you know about the tungsten putty. It is easy and handy, but not the best way to add the most weight to small spaces. People hear the word "tungsten" in tungsten putty and think heavy, it is mis-leading.

Sweet 2-6-0 too! 

[robwill84]

Thanks for the tip on the lead sheet, I found some online and will order a couple ounces. Your 44 tonner is really impressive, I've watched your video of it hauling that long string of cars around many times. Clever to attach the rerail frogs to the trucks too. Are those the ones from Detail Associates?

[delamaize]

I'm not familiar with the sugar cube speaker dimensions, but could one fit in the cab rather than sacrificing frame metal?

[Chris333]

Thanks for the tip on the lead sheet, I found some online and will order a couple ounces. Your 44 tonner is really impressive, I've watched your video of it hauling that long string of cars around many times. Clever to attach the rerail frogs to the trucks too. Are those the ones from Detail Associates?

Pretty sure they are from Miniatures by Eric:
https://picasaweb.google.com/ErieChris333/ProtoPhotos#5921450853421570050
https://picasaweb.google.com/ErieChris333/NScale#5345968895331027266

[robwill84]

Pretty sure they are from Miniatures by Eric:
https://picasaweb.google.com/ErieChris333/ProtoPhotos#5921450853421570050
https://picasaweb.google.com/ErieChris333/NScale#5345968895331027266

Wow, I forgot all about Miniatures by Eric. I ordered some trolley poles from him many years ago. He has some great detail parts.

[robwill84]

I'm not familiar with the sugar cube speaker dimensions, but could one fit in the cab rather than sacrificing frame metal?

I considered that option, but the cab is seriously tiny. I have a 15 x 9.5 micro oval speaker and there's not even room for that. The bottom is really the only option, and will sound the best. A larger speaker will always sound better. (Provided you have a good baffle for it, of course).

[peteski]

Lead flashing should be easily obtainable from any hardware store or home improvement center (Home Depot, Lowe's).  It is about 0'050" thick and you can buy it by the foot (in couple different widths).  You can also buy it by the roll, but that is a bit much for what you need.  I bought some couple of years ago and it was so much cheaper than the specialty online sources.

You can cut it with scissors or by repeatedly scoring it with a hobby knife or a box cutter.  You can stack manyy thicknesses for a larger weight.  Or you can melt it and cast weights with it.

The ZIMO speaker:
http://www.modeltrainstuff.com/Zimo-Small-Speaker-Sound-Chamber-p/zmo-ls10x15.htm
http://www.modeltrainstuff.com/Zimo-Small-Speaker-Sound-Chamber-p/zmo-ls8x12.htm
Out of stock (I bought 2 of each last week). Hopefully they will restock someday (as MBK's prices are very good).

[robwill84]

I found some lead tire balancing weights I had stashed away. With a little trimming they fit in the cab nicely:



Brings the cab up from 1 gram to 13. I don't know how much the material I'm gonna cut off of the bottom weighs, but I bet its pretty darn close to 12 grams, so I'm already breaking even.