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Messages - Rocket_Scientist

#1
Greg,
I do electronic power systems (on spacecraft) for a living and that includes the Solar arrays and battery charging systems and the associated battery packs. The chemistry of those batteries has evolved over the last 30 years from NiCads, Nickle Hydrogen, NiMh to finally LiION.  No offense but I've seen postings like yours over the years about stuff like this with NO technical justification as to why "you can't do it", so time to put some of those myths to rest.

The Sierra system doesn't "expect" anything as far as the battery is concerned. It puts out a charging voltage (just a bit higher than the battery's rated voltage) once track voltage exceeds 6 volts (actually about 8 Volts) at a fixed charging current. Since the original Sierra battery was rated 6V @ 500mAh the Sierra system has a pretty low max charging current (typically <50mA....I've measured it) which is why you'd have to charge on track voltage for almost 10 hours with the original battery. Those Gel Cell Batteries were not very tolerant of high charging currents and the Sountraxx charging circuit is pretty basic.

The NiMh battery packs I've installed in all 7 of my locos with Sountraxx systems are all 6 Volts (perfect match with the Gel Cell) with current ratings from 1700mAh to 2500mAh (well above the capacity of the original). Once a NiHm battery is "full" the Sierra system could only provide at MOST a slight trickle charging current IF I was constantly running at full throttle which I don't. Also of note is the fact that the Sierras output voltage to the battery really isn't regulated to any certain voltage but since the current is limited, once that current limit is reached, the input voltage to the battery drops to just above the batteries rated voltage. Also keep in mind the the current rating of the battery pack only tells you how much current the pack can SUPPLY over a given time frame, NOT how much current is actually being drawn by the load. There is NO WAY POSSIBLE that the Sierra board could damage a NiMH battery or vice versa.....ever. The high capacity batteries that I use will run that sound board all day long, and if you run at high volume, the discharge current from the battery will exceed the charging current from the Sierra board by a fair margin...IE: battery isn't charging. I have the optional charging jack and use a couple of battery chargers with selectable 100mA or 300mA charge rates. I never run my batteries to depletion but at the higher charging rate it'll still take 5 to 6 hours for a full charge on my biggest batteries. At MOST the Sierra system will only trickle charge a high capacity NiMh battery pack.

Many people have used NiMh batteries as replacement for that Gel Cell with zero issues. There's still an ebay seller that sells a replacement "quick charge" NiCad battery pack though NiCads are are terrible substitute because of their memory effect. The one exception to all this are LiION batteries. Those packs require "balanced" charging circuits.....the individual cells are charged and monitored to prevent reverse current flow through any individual cell......they tend tend to blow up if that happens. My oldest NiMh batteries are now 15 years old and have not exhibited any appreciable reduction in capacity since I keep them in a good state of charge. I don't run my stuff all year but I do put them on the charger at least once every 60 days when not in use. Now due to the limited space inside the Climax coal bunker I have just enough room to mount the Sierra board on top of the DCC "jumper board" but not enough room for a 5 cell AA NiMh battery pack under the coal load so i'm going with a 6V 300mA "stick" battery under the coal load which solves my clearance issue. I would have liked more capacity from the battery but again i'd have to run at very high volume for an extended amount of time for it to be an issue.
#2
Large / Re: Climax listed on Trainworld as "New Release"
December 25, 2019, 08:14:40 PM
My Climax arrived just in time yesterday from Trainworld to run around the Christmas layout. Opened for inspection but not yet run, but this is one impressive locomotive. That bunker is chock full of electronics. Since I run DC only, I guess the train gods were smiling on me Monday when I won a NIB Soundtraxx Sierra sound system FOR THE CLIMAX. Looks like the only issue that may come up for the install is making room for the battery pack (5 cell NiMh 6V battery pack to replace what I know is a completely dried out lead acid gel cell still packed with the Sierra sound system). I think if I cut off the mounting bosses for the cooling fan on top of the coal bunker it just may fit but won't know until the sierra board and battery pack get here later this week.
#3
N / Re: N Scale Christmas Train Lights
December 25, 2019, 08:02:33 PM
What train set are you running? If this is the Spirit of Christmas train set then you aren't remembering correctly as this set uses the "Old Timer" passenger coaches which in their entire history have never been lit. Bachmanns' newest 72' and 85' passenger coaches are lit as are the old 60' passenger cars  from their "Plus"line (no longer in production). The newest lit coaches use LED lighting and the old Plus line uses regular incandescent bulbs. Even the Pennsylvania Broadway Limited set which uses a reincarnation of the 60' coaches are not lit.

I have numerous sets of the old Plus line that i'm converting to LED lighting myself as these coaches are always showing up on Ebay either individually or as 3 or 4 car sets. I'm using surface mount bridge rectifiers and caps with the LED mounted on my little custom circuit boards.
#4
N / Re: Parts Availability
April 18, 2018, 06:09:41 AM
And just as an update, I sent my Northern in for repair/replace (most likely to be replaced since it's of the 2004 - 2012 vintage).....6 to 8 week turnaround time. Now looks like i'll have to send another loco in, as apparently there are no spare parts listed for the ALCO 2-6-0 mogul. I run straight DC and the locomotive was just tooling along and suddenly slowed down and stopped. The LED headlight comes on dim for a moment and then goes out...either direction. Looks like the dual mode decoder gave up the ghost since all other locos run fine....clean track and a hefty Spectrum power supply. I wonder if it may be easier to just remove the decoder and hardwire everything in the tender along with a dropping resistor for the LED headlight. The wiring looks pretty straight forward since everything is labeled as to what goes where.
#5
N / Parts Availability
March 27, 2018, 12:34:25 AM
This post is mostly for the "Bachmann". I've been wondering how long it will be before a new parts shipment arrives. I've noticed a LOT of items that are "sold out".....not discontinued, just out of stock and have been for quite a while. Case in point, i'm trying to rebuild a northern 4-8-4 bottom end that has seen better days but hard to do that when both the wheelset AND the complete wheelset and valve gear assembly (which is what it really needs) are BOTH out of stock. Rapido conversion couplers, motors, even traction tires are impossible to order right now because they've been out of stock for months on end.

Also if I need a motor for a 4-6-0 Baldwin, how about offering just the motor and not the complete frame or chassis assembly. Shouldn't have to spend $36 if all you need is the motor. Just wondering if we could get an update for those of us that are having projects/refurbishments being held up due to lack of parts.

Thanks!
#6
N / Re: bachmann class j poor linkage
November 15, 2017, 11:51:36 AM
Something doesn't sound right here. The Class J does not show as discontinued and there are plenty of parts available on the parts department page for this model. Nothing indicates discontinued. This sounds like the older white box or "special edition" version which has been gone for some time. With the warranty there should have been no problem with a replacement if they didn't have the parts to fix. Hmmmmm
#7
N / 4-4-0 American drive shaft
January 03, 2017, 01:17:36 AM
Ok,

I have 3 of these 4-4-0 virtually new in the box that i've had for many years. These models are the generation where Bachmann went from the very large cup style driveshaft to the very small ball/pin style. I was running one (The B & O) to break in, and apparently there was very little lube in the sockets and after an hour or so of running, I had a lock-up that actually flipped the loco right off the track from the motor torque.

Lubed everything and ran the loco with a small power drill just to make sure no binding in the mechanism. The driveshaft itself had snapped in half. Ordered new ones and apparently this latest generation has a slightly longer drive shaft. I haven't pulled apart one of my undamaged 4-4-0's to actually measure the shaft so just asking if off hand anyone knows what the exact length the shaft should be. The latest version is 10mm. Looking at the pieces of the old shaft compared to the new version it looks like maybe somewhere between 1 to 1.5mm shorter. The longer shaft prevents the loco from sitting square on the track as the extra length causes the engine to bow up.

Since bachmann doesn't list this intermediate generation part, any idea where i can find the right sized shaft? Oh and the instruction/parts list that came with the loco actually listed the older hex cup style shaft, not the correct one that's actually in the loco itself. Maybe the "Bachhmann" can see if there's any NOS laying around? Thanks!
#8
N / Re: Trim a train instructions
December 21, 2010, 06:40:59 PM
Cody, it's highly doubtful that bachmann has any replacement parts for that set as they stopped making them quite a few years ago. I have a complete set that's still in use (on the tree right now) but basically there should be:
4 pieces comprising the green base that snap together

12 pieces of 11.25" radius track that screw onto the base with self tapping screws which should be provided...note that those little self tapping screws are required to not only hold the track down but also keep the track in contact with the track to pack connector screwed onto the bottom of one of the base sections

4 straight support arms that slide into the 4 seperate holes on the inside of the base sections

4 angled support arms with locking thumb screws that slide over the straight support arms. these arms are what is used to level the track.

The "walwart" power supply with switch that connects to the electrical terminal on the base.

I'm pretty sure I still have the instructions with the parts list. If you need that i'll see if i can dig it up
#9
N / Warranty question for the Bachman
January 03, 2009, 08:04:28 AM
Just want to see if I can get a clear answer on this before I stop at the philadelphia facility later on this week.

I keep seeing references to needing reciepts for warranty coverage and whatnot. Does that also apply to older locomotives with the "lifetime" warranty? My Northern 4-8-4 front left driver will no longer stay attached to the gearbox (i'm pretty sure the plastic gear inside has cracked where the axel goes in), as well as two sickly 4-4-0 americans, one heats up pretty badly after a few minutes of running and starts to stall,  and the other is pretty much dead.

Does Bachmann REALLY expect to have a reciept after 17 years? Still have original box and all paper work with the locomotive purchased in 1991. A reciept wouldn't last that long anyway..they fade away after a year or two. Same thing with my 4-4-0's . Had'em for years with very little run time, One purchased by itself, the other from a set.

I need some replacement parts anyway to revamp some of my oldest locomotives but in all the times i've been there over the years i've NEVER had to bring in a reciept.

Or am I reading this all wrong and the reciept is only required for the "free" replacement or repair VS the $10-$15 charge for locos after the first year?

Anyway, I've still enjoyed seeing the shop area when i've stopped by in the past. Last time I was there i was asked if i'd like a job in the repair department... ;D Wish I had had the extra time to take the position  :D