Click on the link below for an article which should help you:

http://members.shaw.ca/sask.rail/dcc/tmaster/tmaster.html

I suspect Hunt is correct about the decoder being a non-silent one.  Most decoders today pulse the locomotive's motor at a rate too high for humans to hear.  These are generally referred to as silent or ultrasonic decoders.  However,  Bachmann's decoders use a lower pulse frequency, one that can be heard by most human ears.  I suspect this is to maintain compatiblity with their radio frequency interference rejection filters that cause problems with silent decoders but meet international regulations for RFI.  Whatever the reason, I suspect this is the root cause of your problem.  If so, switching to a silent decoder should solve the problem.

There can, however, be other sources of the problem.  I think we can eliminate any problems with your Zephyr as you do not mention this happening with any other locomotives.  And we can eliminate gear problems as the pitch of the hum does not change with speed.  But your comment about sounding like a bad ballast in a fluorescent light fixture suggests that something may be vibrating mechanically in sympathy with the motor pulses.  This could be anything from the shell of the locomotive to a scrap of iron held on or in the motor by the motors magnets and being vibrated by the pulses that operatre the motor.  If it is sympathic vibrations in the shell, these will usually stop when you touch the shell with a finger.  Internal problems may require disassembly of the locomotive.  In that case, you may prefer to return it to Bachmann for servicing.

Quote from: msowsun on May 03, 2007, 10:12:53 AM
Is it possible that  Bachmann N scale EZ Track turnouts are "Route Selective" but don't require special wiring considerations because they are wired like Peco Insulfrog? (which are also route selective)

I wondered about that too.  But reading about Vinny's problem strongly suggests that Bachmann N scale EZ Track turnouts are non-insulated route selective ones and are at the root of his problem.

This solution is not much different than msowsun's.  It eliminates a few unnecessary gaps and adds some closer to the turnouts that require them.  The advantage is that when you stall at a turnout, you will know it is that turnout that is set the wrong way.  But if you stall between turnouts, as with msowsun's solution, it is not intuitively obvious which turnout is set wrong.  I have Shinohara route selective turnouts all over my H0 layout and went through the same problems until I learned Lynn Wescott's rules for gapping route selective turnouts.  The gaps are shown in white.  The feeds from one power pack are shown in red and those from the other power pack are in green.  Note that all these gaps and feeders are also required for DCC operation with route selective turnouts.

Quote from: Ten Wheeler on May 02, 2007, 03:29:42 AM
... makes a terrible humming noise when I turn on power on my Digitrax Zephyr... The noise ... starts at a "crawl speed" thru faster speeds.

I am confused about when the humming noise starts.  Does it
(a) start when you power up your Zephyr or
(b) start when you turn on track power on your Zephyr or
(c) start at a crawl speed or
(d) start at faster speeds

If you would tell us what Zephyr power you are turning on and at what speeds the humming starts, I think we would have a better chance of figuring out what is happening.

Mounting the control switches on a piece of board may help, even if all you use is double sided tape.  But a better alternative, IMHO, is to use miniature push buttons mounted in a control panel that shows a track plan of your layout.  I have used two push buttons per turnout, one on each side of each turnout's symbol on the control panel.  The one on the left of the symbol throws the turnout to the left.  The one on the right throws the turnout to the right.  This type of setup makes it much easier to figure out which button to push for which turnout.  This becomes increasingly important as the number of turnouts increases.

Atlas slide and push control switches will also work with Bachmann turnouts, but require a bit more work to wire them up.

I believe SteamGene was confusing switches with turnouts when he posted his otherwise excellent advice.

Chuck, you do not mention whether these two Shays are your only locomotives and whether you want to operate them together (double headed) or alternately (only one running at any one time) or both at the same time but independently controlled.  If it is the latter, then DCC or radio control make sense.  If one at a time or double headed, then staying with dc is more cost effective, even if you have to buy more expensive sound cards.

Just to give you some ideas, a friend has two of the original Shays that he runs at home on dc but wanted to run with a group on DCC.  He also wanted sound.  The most effective solution was to fit one of the locomotives with a Digitrax decoder and a Sierra sound card.  This allows him to run that one Shay on DCC with all the bells and whistles.  At home, he can run that one Shay on dc with all the bells and whistles or he can double head both Shays, still with all the bells and whistles.  Two sound cards would have been over kill in this case.  The intent is to eventually switch the decoder and sound system to the second Shay if/when the first one shows signs of aging.

What will work best for you will depend on just what you want to do with these locomotives.

If you have a good table saw and know how to use it, you can cut your own wood.  You can rip as fine as 1/16" the traditional way (between the blade and the fence) if you keep the wood from disappearing down the throat with a  tight fitting throat plate or a false plate made by clamping a piece of plywood to the table top and raising the blade through it.  Cutting 1/32" and even 1/64" strips is possible by cutting them off on the outside of the blade and moving the fence the width of the blade + 1/32" or + 1/64 inch between cuts.  ** see note below

For safety reasons, it is unwise to rip pieces of wood less than about two feet long.  It is easier to rip scale size boards to width first and then to thickness.  That way, you are always ripping from a substantial piece.  And expect lots of waster, even with a thin kerf blade.

I like to build with cedar for large scale outdoor applications.  For H0, cedar is too soft.  Spruce, pine and fir seem to find their way to my door step, so I use quite a bit of them.  I have also been known to rip the surface layer off plywood as a source of poplar, birch, walnut, and occasionally other exotic hardwood plywoods.  If I have to buy wood (which is very rare, I normally use scraps) then I buy birch.  Bass is available here but is much more expensive that birch and very little different in working.  I do not normally use oak where it will be seen as its pores are huge in H0.  But I do occasionally use mahogany, the Philippine kind, where I want to model old, abused wood.  I have also used bamboo, particularly kabob skewers for posts and pilings.

For glue, my favourite is Weldbond applied full strength.  To get the tiny little dots of glue required in H0, I fill a 10 cc syringe with the Weldbond, add a blunted 16 gauge needle, and use that.  To keep the needle from drying out and clogging, I keep it in a glass of water.  When making lots of joints, I keep a piece of paper towel next to the glass to quickly wipe the needle every time I use it.

Has anyone else tried tea, iron wool and vinegar to age their wood projects?  This is the next thing that I am experimenting with.

** Note:  table saws are a great way of separating fingers from their owners.  Unless you are thoroughly familiar with the safe and proper use of table saws, do not attempt fine ripping.  In spite of its small size, or maybe because of it, ripping fine material is harder than ripping fence boards and other large material.  Ripping fine material is NOT the way to learn to use a table saw.

Quote from: SteamGene on April 13, 2007, 07:19:11 AM
...  it seems the only difference between a district and a sub-district is that one is powered directly by a booster and the other goes through a power manager. 
Gene

Close, maybe half a cigar for this one.  A district is all the trackage that is powered by a booster.  A sub district is one of several divisions of a district.  Each sub district has its own power management.  It is unnecessary to divide a district into one sub district as each booster has its own power management built in.  So no, they are not equivalent except for a power manager.

The reasons behind districts and sub districts are quite different than the reasons for blocks on a dc railroad.  With DCC, the concern is providing enough power for all the trains without providing enough power at any one point to weld the locomotives to the rails in case of a problem.  Independent control of locomotives is inherent in the system.  With dc, the concern is keeping all the locomotives powered separately so that you can control them independently.  Power distribution is inherent in the blocking.  From an operational strand point, the major difference is where speed and directional control take place.  Imagine 10 men operating a DCC layout.  Each controls the power in his own locomotive (and only in his own locomotive) using speed and direction controls.  Imagine the same 10 men operating a dc layout.  Each controls the power in his own locomotive (and only in his own locomotive) by disconnecting the block of track on which his locomotive is running from all the other blocks of track and connecting that block of track to his own power pack (and only his own power pack.)  In the DCC case, all he has to worry about is speed and direction.  In the dc case, he has to worry about speed, direction, which block of track he is on, which block of track he will be on next, and whether someone else is already using his next bock.  Thus the expression - DCC is controlling your trains.  dc is controlling your tracks.

Question - a blind man walks into the middle of a model railroad operating session.  Without asking anyone, how can he tell in the first 30 seconds whether the layout is operated by DCC or by dc??

Answer - He just listens.  If he hears "look out, we're going to crash" he knows it is DCC.  But if he hears "who's got my block??" he knows its dc.

Moulds are very expensive to make.  If I were a manufacturer, I would want to get as much use out of my expensive moulds as possible.

I did not look up prices, but if forced to make a wild guess, I would guess that the background models cost 2/3 to 3/4 as much as the full model.  To reduce costs, you can often buy the full model and assemble it as two background half-models, using a blank piece of styrene as the back of each half-model.  As a bonus, it looks like the full models you have shown come with all the neat things on the roof but the background models do not.

I have even gone so far as to take completed models and cut them in half on a band saw. 

The ampacity of wire varies depending on insulation and application.  For example, #22 wire used in a transformer winding is rated at low as 1 amp but in a cable with other wires, can carry 5 amps.  In open air, it can carry 8 amps at normal temperatures.  My advice is to avoid burying it in the styrofoam if that is what you use on your layout.

But even if you buried it in the styrofoam, the chances of starting a fire are remote.  If the wire got hot enough to melt the styrofoam, or even its own insulation, that melting would extract heat from the wire, tending to cool it.  Eventually, you would end up with bare wire sitting inside a open "tunnel."  If you have ever used a hot wire styrofoam cutter, you have probably noticed how the wire cools when cutting and if you stop cutting with the wire still in the styrofoam, it slowly forms an open hole around itself without reaching the smoke point, let alone the ignition point.  Also from working with hot wire cutters, I seem to remember heating in the order of 1 to 4 watts per inch of cutting wire, depending on the type of foam being cut.  If we were to translate that to #22 wire, 1 watt per inch at a resistance of 16 ohms per 1000 feet (.0013 ohms per inch) would require a current of about 20 amps to produce 1/2 watt per inch in a single wire or 1 watt per inch in two wires side by side.  The 7 amps of so that a B-mann booster can put out would cause only 1/8 as much heating.  Bottom line, in open air, no problem.  Encased in styrofoam, no problem, but I wouldn't do it anyway.

A power manager like a Digitrax PM42 can be a good choice.  One of its neater tricks is allowing the full five amps of a five amp booster to be available to each and every subdistrict, but still not shut down the booster even if three of the four subdistricts is shorted.  At first, this seems impossible - three shorted sub districts each drawing 5 amps and a forth district still in operation with five amps available to it would appear to be 20 amps total.  And if you were using current limiting to each sub district, for example, by using incandescent lamps, it would be impossible.  A 5 amp booster cannot produce 20 amps.  It cannot produce even 10 amps, at least not continuously.  But it can produce 10 amps for a small fraction of a second.  And herein lies the secret.

When a sub district is shorted, the PM42 shuts off that district until the short is cleared.  How does it know if the short is cleared?  It applies power to that sub district for a very short time, just long enough to see if the short still exists.  If it does, it cuts the power to that sub district and tries again a little later.  If more than one sub district is shorted, then the PM42 shuts off all the shorted sub districts.  Every once in a while, it test the shorted sub districts to see if any of the shorts have cleared.  But it does not test them all at once.  It tests them one after another, so that there is never a moment in time that the booster is asked to deliver more than 10 amps.  And this 10 amps is never drawn for longer than a small fraction of a second.

So why doesn't the 5 amp booster shut down when asked to produce 10 amps?  It is all a matter of timing.  The PM42 must be faster than the booster.  It must shut down its sub districts before the booster can shut down.  This is why a PM42 will not work with, for example, an MRC Power Station 8.  The PS8 shuts down quicker than the PM42, so the PM42 cannot test a shorted sub district without shutting down the PS8.  If you plan to use a PM42 with other than a Digitrax booster, I strongly suggest finding out from the booster manufacturer either how fast his booster shuts down or whether it has ever been shown to work with a PM42.

I will leave the discussion of Tony's Power Shields to someone who has actually used them.  I have no idea how these devices test for shorts or the speeds that may be involved.   

Quote from: RAM on April 11, 2007, 10:39:57 PM
i would think that you would Block on any layout of any size even if you are the only operator.  It makes it easier to find shorts.

By all means.  But do not confuse multiple blocks with multiple power districts.  As an sole operator, you might divide your layout into a dozen blocks for fault finding but still have only one power district.

I have used a modified 20 pound propane cylinder as a carry air tank for many years.  It is fitted with a safety valve, a fill valve, a drain valve, a pressure gauge, and of course a pressure regulator to keep the air brush pressure constant as the tank pressure drops.  I find it much more convenient than trying to move the compressor from the workshop into the house and down the basement, where the H0 layout is.  I rarely have to make a second trip to the shop to refill the tank if I am only doing a small job like painting a locomotive.

Incidentally, propane tanks are rated for a higher pressure than most carry air tanks.  Think of the propane cylinder in the black cupboard under your barbeque or the spare cylinder in your garden shed on a hot, sunny day.  Its temperature can easily reach 55 degrees (or about 130 degrees Farenheit).  At that temperature, the pressure of the propane is around 260 or 270 psi. 

Quote from: Seasaltchap on April 11, 2007, 10:42:51 PM
Jim : It's Stewart.

My appologies to both you and Sheldon.

Many things will bond styrene.  Common lacquer thinner works well, particularly for large areas.  As an example, laminating multiple 4' x 4' sheets of thin styrene to make a thick, strong mockup of a full size locomotive boiler. 

You may use the word "vulcanization" any way you wish, but don't let Vulcan, the Roman god of fire and volcanos hear you using it in ways that do not include fire and brimstone (heat and sulphur if you prefer.)  You might also upset Charles Goodyear's ghost if you apply the term to anything but rubber.  Actually, Goodyear's serendipitous discovery of the process of vulcanization is an interesting story in itself.