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Driver surfaces ? Brass or NS ?
Long95209
Batter up group ! There's been a LOT of discussion about whether or not there is a great deal of difference in materials , BTW Bowser had both surfaces [?] the majority of my collection is brass . Does it make a big difference ? I don't know for sure , but if the surfaces arean't clean ? Trouble ! Please jump in group ! Henry H.
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开云体育Well I can’t say much about brass vs NS but I can speak from experience about the difference between sintered metal and NS. By actual comparison NS has comparatively poor adhesion on NS track. ? My “Athearn” Baldwin S-12 with an Cary built (lead-antimony) Cary Alco S-2 shell along with added lead, a Sagami 2032 motor w/brass flywheels and Ernst gears was able to easily switch a cut of 56 5 oz. 40 ft. freight cars, all with C.V. trucks on my friends (Cal) layout. After the switch to NWSL NS wheels it hard a hard time moving anything over 40 of the cars in the yard. That coincided with Cal’s change to Command Control but that really had nothing to do with it as the problem was wheel slip. ? Although not a direct comparison, my thoughts are that brass wheels would have similar traction to the sintered metal. Having started on HO around 1949 I have much experience with brass drive wheels. ? So far as cleanliness if one’s track is clean kept brass and sintered metal work just fine. So far as electrical pick-up all will work okay but I agree that NS gets a bit of the nod here. A more important consideration to me is having reasonable clean rail without being so clean and dry that arcing is promoted. ? John Hagen ? From: yardbirdtrains@... [mailto:yardbirdtrains@...] On Behalf Of Long95209
Sent: Sunday, January 06, 2013 10:55 AM To: yardbirdtrains@... Subject: [yardbirdtrains] Driver surfaces ? Brass or NS ? ? ? Batter up group ! There's been a LOT of discussion about whether or not there is a great deal of difference in materials , BTW Bowser had both surfaces [?] the majority of my collection is brass . Does it make a big difference ? I don't know for sure , but if the surfaces arean't clean ? Trouble ! Please jump in group ! Henry H. |
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John, one of the guys in my earlier posts responded with a product he recommends called Flitz, which I just order last night on Amazon. My drivers on my H9 are brass(probably worn down to the brass???). I have used Goo Gone to clean them. But, as he mentioned about his club, my club's rails can get quite dirty and maybe the Goo Gone isn't doing the trick anymore. So, I want to give that a try. The reason for the question was, my L1, that is set up the same way as my H9 is operating rather nicely and has the NS drivers. It's like some one put a resistor in line with the motor on the H9. This will be my last try to improve the conductivity before I add the pickups.
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Thanks again to everyone who has offered their helpful advice. Mark --- In yardbirdtrains@..., "John Hagen" wrote:
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lnnrr
I'll throw out some opinions and observations here, some of which may
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not be popular. I think brass wheels on steel rail get the best traction. I don't use either because of oxidation (AKA rust). Nickle silver gives less traction than brass but does not have as much oxidation problems. And I think looks more like prototype than brass. Brass tires that have been bright plated seem to be the most slippery. Let them spin long enough and the plating wears off. Better pulling, back to looking like brass. Can't speak about sintered metal because I've only seen that on non-steam. I know it is rather porous compared to solid turned materials. I know most folks think clean and dry is the only way to get good operation. A club I used to belong to cleaned weekly and sometimes during an operating session. My friend with the most dependable operating layout I've ever seen operates "wet". Twice a year or less he wipes the layout then adds a few drops of Automatic transmission fluid. There is a product in some hobby shops, a few dollars for a couple of ounces, that is supposed to be good for your track. My friend with the wet layout took some of that stuff to the lab at Chevron where he worked. It was ATF, automatic transmission fluid. Remember Loys Toys? Sold a lot of DCC stuff? Loy visited my friends layout and thought it was terrible when his fingers got dirty on the track. But there was never a hesitation or contact problem during the whole operating session. Opened his eyes. Warning. ATF is not oil. Not the same as 3 in 1 or what you put in the crankcase. But if you don't have good success with keeping your layout clean, you might want to try going the other way. Try running ATF. It may seem like "going to the dark side" but it works for some people. Chuck Peck --- In yardbirdtrains@..., "Long95209" wrote:
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Tom Knowles
开云体育Mark, It occurs to me you may have a
bad HH motor if the problem is not traction related. Do I
correctly understand its a traction problem? We may be able to
quantify your problem:
An interesting generalization that may translate into understanding your problem, is on rating a full size steam engine. I think it can translate to model engines (without traction tires). It's "factor of adhesion", expressed as a percentage. If an engine has specified a factor of adhesion, it is usually on the order of 25%. So if the engine weighs 100,000 lbs, then expect no more than? 25,000 lbs of "drawbar pull" (sometimes called Tractive effort, or "TE") from it. This was measured by Dynamometer cars in the old days, with other computations complicating the use of the car and its results! ?I have experimented a bit with model TE, and found though the margin for error is greater since we're dealing with smaller numbers and less accurate systems to measure it, the numbers translate. If the engine weighs 16 0z, expect 4 oz TE. To measure this, I have used a postal scale, set on its side and zeroed for that position to verify this. Being a static measurement, its crude, but informative.? One could measure the voltage and current during the session, but until anything moves, HP cannot be computed. If the engine slips in the test, then TE will be lower at that point since sliding friction is less than stopped friction. Incidentally, that is partly why steam engines at low speed have difficulty starting/accelerating sometimes, the pulses of power from each stroke unevenly apply force to the adhesion, a momentary overcoming of the adhesion will cause the wheel to slip. Electric power is smooother, and the high current required by as motor at stall translates to "force". This is an excellent situation for getting started and should be the case with electric driven model steamers. Try making a test track, set level, and employ some sort of measuring system to compare both your L's and the H and see what happens.....can you do this in DC and measure the voltage and current? Another way may be to simply raise one end of the test track and see what grade the engines will pull before slipping. If the H9 slips early, then I think you're still looking at traction problems. I would love to have a working dynamometer car that could radio out the results of all the parameters of a dynamic test in scale, but have lost too many brain cells to carry out that project at this age.. It may already be available in DCC if we knew how to read out the motor's back emf and load from the decoders that have this feature. Anyway, I think you are in the right forum to figure this out, bear with us! Tom Knowles NOTE NEW ADDRESS: tomk@...On 1/6/2013 12:44 PM, twilight022765 wrote: ? |
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Goo Gone cleans and leaves an insulating layer behind. I've used it and seen the layout go dead as a result the following morning.
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Do try any kind of tuner cleaner on those wheels. Or go to one of the good hardware stores, auto parts supply stores, or marine supply stores and get a can of the electronic cleaner and conditioner you find there. Most of the time its a CRC product Advanced Auto Parts has " CRC QD? Electronic Cleaner" for a bit over $7 in a large spray can. Wet a Q-tip with it and wipe the driver tires and other electrical surfaces with it. You can do the same with your rails [wipe about 6-inches every several feet apart then drive around the layout] and you'll see a marked operating improvement in a matter of seconds. Do the complete electrical path on the loco's and your track switch points and you'll feel like you have gold plated electrical contacts on everything. That includes even old zamak slabs that are part of the electrical path on old models, treat contact points and any screws that are part of the electrical paths. Case in point, it makes an ancient Athearn 0-4-2t Little Monster that is largely a zamak electrical path and has sat for 20 years, run like a new Kato after that treatment.... that and a wisp of fresh oil and axle lube in the right places. This is my personal experience with the stuff and that model as well as many others. Models that simply never were known to run decently in the first place. Don't overlook places like the body pads under the tender trucks and the place where the washer like connector wire goes between the locomotive and the tender. Back off such screws and wipe both the threads and the contact area under the screw heads and the connector 'washer', then snug down to working positions. I'm certain you will be amazed at how much better the model operates when you have conditioned the electrical points that have become oxidized and thus somewhat insulated over time........ with just a certain fluid. Best to ya... Mike Bauers Milwaukee, Wi, USA On Jan 6, 2013, at 12:44 PM, twilight022765 <twilight022765@...> wrote:
John, one of the guys in my earlier posts responded with a product he recommends called Flitz, which I just order last night on Amazon. My drivers on my H9 are brass(probably worn down to the brass???). I have used Goo Gone to clean them. But, as he mentioned about his club, my club's rails can get quite dirty and maybe the Goo Gone isn't doing the trick anymore. So, I want to give that a try. The reason for the question was, my L1, that is set up the same way as my H9 is operating rather nicely and has the NS drivers. It's like some one put a resistor in line with the motor on the H9. This will be my last try to improve the conductivity before I add the pickups. |
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开云体育Plain brass will oxidize fairly quickly, whether operated or not.?
Same with brass rail.? Back in the day we used a product called No-Ox,
which was one brand of electronic contact cleaner, and it made a big
difference.? I've heard of folks recently using ATF fluid.?
Annecdotally, the product Rail-Zip is ATF fluid in a small bottle marketed to us
train guys.? Assuming all surfaces are clean, there should be no detectable
difference in current transmission among any of the commonly-used metals -
brass, NS, copper, even steel.? As an earlier poster noted, there might be
an issue with the motor itself - maybe a short in the armature that's causing a
big draw??
?
?
DM |
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Tom, do you think this device will work?
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Kind of sounds like something your doing with your scale set on it's side. If it is something you think that will work I think we have one of these at my club. I might have to shake some trees to find it but I believe I recall having been told it is there. I can use it to compare drawbar strength between the two locomotives, the L1 and H9. Which I think are the same HH motors, the L1's motor has a flywheel on it though. Let me state another observation I've made with the H9. When I set it up to operate in DC mode I don't always get a response from the locomotive. But when I set it back to operate in DCC the locomotive responds. Could this be a sign of a bad motor? Maybe like a car starter when it hits a dead spot and you have to whack it with a hammer? BTW, when I had set up the loco to run DC through the decoder the H9 moved very swiftly and seemed strong. Mark --- In yardbirdtrains@..., Tom Knowles wrote:
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Tom Knowles
开云体育Well, it seems like your on the right
track...er excuse the pun.
Yes, that digital pull meter look s like the ticket. OOps another one.. This is nice looking item and a reasonable price. If it has a peak-hold feature, even better. I think if it were me, I would remove (unwire) the decoder and just wire the thing straight dc, and see how she does. .. Trouble-shooting 101: divide and conquer. BTW, since we're on the subject, yes I have used ATF on many layouts since about 2000 with excellent results. Like Brylcreme..a little dab'l doya Tom Knowles NOTE NEW ADDRESS: tomk@...On 1/6/2013 7:55 PM, twilight022765 wrote: ? |
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Mary Long
--- On Mon, 1/7/13, Tom Knowles wrote:
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lnnrr
I haven't seen one of the MicroMark digital pull meters but I would
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be concerned about accuracy of a hand held meter. Perhaps the instruction sheet details how to give it a fixed mount. I have a board about five foot long with track mounted on it. One end has a pulley on the centerline of the track. A bit of fishing monofiliment has a loop on one end to engage a coupler and a hook on the other end where I hang a small pan. Pouring shot into the pan gives me an adjustable load until the engine starts slipping. Then I weigh the shot for the tractive effort. Little "saddlebags" of shot are handy to add weight until I stop the slip or the amperage starts getting too high. Just leveling the board on the workbench with the weight hanging off the end gives me repeatability enough for model work. Other than the track, it was all just stuff I already had laying around. Low tech, low cost, works for me. Chuck Peck --- In yardbirdtrains@..., "twilight022765" wrote:
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rubbing alcohol works great for cleaning track. leaves no residue.
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emmet d --- In yardbirdtrains@..., Mike Bauers wrote:
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Tom Knowles
开云体育You are correct, Chuck. The data from
holding by hand is "near-field data" often used for quick and
dirty theory verification, but since there seems to be a
significant difference in the performance, accuracy would be the
second step! First answer: yes there is a difference. Second
answer, this is how much it is+ or-.
I believe your set-up is how us HE's ussta do it. This includes the magazines for their test drive reports. I don't know how they do it now, but bet its digital: The cost cries out "USE ME!!" Low tech for me was using an old plastic postal scale on its side! Tom KnowlesOn 1/6/2013 10:45 PM, lnnrr wrote: ? |
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Tom Knowles
开云体育Emmit, did you mean denatured alcohol?
I thought the rubbing stuff had a lubricant in it...I did not know
this insulating property of Goo Gone either, which I sometimes
use. Since I always have lacquer thinner here and in small bottles
on the workbench, that's what I usually use to clean wheels and
track with excellent results.
A thought about traction differences in scintered wheels smooth or NS tires: My old Athearn units have either of these two driving wheel set-ups. 1) NWSL which I believe are machined and polished NS, seldom need cleaning and traction is within my limits. ? I have one engine with Jay-Bee wheelsets that is so-so. 2) polished scintered Athearn wheels. I never allow an Athearn to escape my shop without this step. See below: Athearn wheels, though porous and rough as we know (perhaps aiding traction a bit), get a shine that seems to help prevent dirt build-up and aids current pick up. I've noticed no reduction in TE, but I seldom work my engines to the limit. Since I always disassemble the trucks to clean and lubricate as well as check for the chronic cracked gear syndrome I remove all wheels when I build or repair an Athearn engine. I put the wheel/axle stub in a drill press, and polish the tread surface in three steps. Start with 400 emery and go to 600, then 800 or1000 grit autobody emery with the part spinning pretty fast. I have run the pair of F's at the museum two years now with no cleaning of wheels. Zero. These two dedicated Museum property Athearn F's are both powered "super power", pulling a string of 7 stainless redetailed Athearn cars. All but one car has wipers on the axles for interior lights, adding to the drag. There is one grade for them each time around of about 2% with a reverse curve. Using transistor throttles on a fixed setting, they prototypically slow down there. I've never detected a slip, but not loaded them to the max as in a long freight consist. I traded my BLI heavy Mike w/ DCC and sound (L&N 1776) to a fellow near here for a DC sound equipped version BLI light Mike. The new engine will become another NC&StL steamer, but for use at the museum on DC which is preferred for simplicity. Sound is a big hit with visitors. The DC with sound is interesting, and runs great. The sound is good, pretty-well synchronized and sharp cut-offs till it gets to above maybe 50MPH, then becomes a weird "shuffle". The engine I traded was DOA to the other guy, much to my embarrassment having never failed me. We met at the store where we did this swap to t-shoot(The Dixie Flyer, Wartrace Tennssee...trackside on the old NC&StL) and yes, the engine was dead. Shorted! Nothing getting hot except the power pack. I did a few things and did some disassembly and re-checks, never finding a thing wrong. Put the engine back together and lo-an-behold!, she works fine now. Not a clue as to what was wrong. When I was in Industrial Electronic repair,? I ran into this scenario most of the time. One particular motor controller kept coming back to us as non-functioning, and we never found a problem with it. We finally decided the unit just like the looks of the technician, so we took a picture of him and taped it inside the cover. It shipped back to the customer with evidently never another trouble. Electronics: BAHHH. Health-wise I am much better, but have no stamina. Working on that.... Tom KnowlesOn 1/7/2013 4:00 AM, emmettdene wrote: ? |
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Long95209
forget stamina for now ! Your wry sense of humor is ba''ak !
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Henry --- In yardbirdtrains@..., Tom Knowles wrote:
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lnnrr
Henry, Tom would have a lot more of that stamina stuff left if
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he drove something he didn't have to push up those Tennessee hills. I just figure he's been on that Cowan turn so long he thinks it's natural to push everything uphill just like the railroad did. Chuckles --- In yardbirdtrains@..., "Long95209" wrote:
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yep just plain old drug store rubbing alcohol.
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emmet d --- In yardbirdtrains@..., Tom Knowles wrote:
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--- In yardbirdtrains@..., "emmettdene" wrote:
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开云体育
Hi Emmet, Just to clarify what Tom was asking.? Plain ole drug store RUBBING alcohol is not plain ole.? It has oils in it to make it easier to rub into the skin.? (Not sure why you would want to rub it into skin?)? So, when you buy alcohol for modeling work, you should make sure it doesn't say RUBBING on the bottle.? Go for either 70% or preferably 97% plain alcohol with no rubbing oils in it.? The oils leave a deposit that eventually puts dirt on wheels and rails.? Also if you use it with india ink or other various modeling uses, it give strange and unpredictable results. Regards, Vic Bitleris Raleigh, NC To: yardbirdtrains@... From: emmettdene@... Date: Tue, 8 Jan 2013 10:39:16 +0000 Subject: [yardbirdtrains] Re: Driver surfaces ? Brass or NS ? ?
yep just plain old drug store rubbing alcohol.
emmet d --- In yardbirdtrains@..., Tom Knowles wrote: > > Emmit, did you mean denatured alcohol? I thought the rubbing stuff had a > lubricant in it...I did not know this insulating property of Goo Gone > either, which I sometimes use. Since I always have lacquer thinner here > and in small bottles on the workbench, that's what I usually use to > clean wheels and track with excellent results. > > A thought about traction differences in scintered wheels smooth or NS > tires: My old Athearn units have either of these two driving wheel set-ups. > 1) NWSL which I believe are machined and polished NS, seldom need > cleaning and traction is within my limits. I have one engine with > Jay-Bee wheelsets that is so-so. > 2) polished scintered Athearn wheels. I never allow an Athearn to escape > my shop without this step. See below: > > Athearn wheels, though porous and rough as we know (perhaps aiding > traction a bit), get a shine that seems to help prevent dirt build-up > and aids current pick up. I've noticed no reduction in TE, but I seldom > work my engines to the limit. Since I always disassemble the trucks to > clean and lubricate as well as check for the chronic cracked gear > syndrome I remove all wheels when I build or repair an Athearn engine. I > put the wheel/axle stub in a drill press, and polish the tread surface > in three steps. Start with 400 emery and go to 600, then 800 or1000 grit > autobody emery with the part spinning pretty fast. I have run the pair > of F's at the museum two years now with no cleaning of wheels. Zero. > These two dedicated Museum property Athearn F's are both powered "super > power", pulling a string of 7 stainless redetailed Athearn cars. All but > one car has wipers on the axles for interior lights, adding to the drag. > There is one grade for them each time around of about 2% with a reverse > curve. Using transistor throttles on a fixed setting, they > prototypically slow down there. I've never detected a slip, but not > loaded them to the max as in a long freight consist. > > I traded my BLI heavy Mike w/ DCC and sound (L&N 1776) to a fellow near > here for a DC sound equipped version BLI light Mike. The new engine will > become another NC&StL steamer, but for use at the museum on DC which is > preferred for simplicity. Sound is a big hit with visitors. The DC with > sound is interesting, and runs great. The sound is good, pretty-well > synchronized and sharp cut-offs till it gets to above maybe 50MPH, then > becomes a weird "shuffle". The engine I traded was DOA to the other guy, > much to my embarrassment having never failed me. We met at the store > where we did this swap to t-shoot(The Dixie Flyer, Wartrace > Tennssee...trackside on the old NC&StL) and yes, the engine was dead. > Shorted! Nothing getting hot except the power pack. I did a few things > and did some disassembly and re-checks, never finding a thing wrong. Put > the engine back together and lo-an-behold!, she works fine now. Not a > clue as to what was wrong. When I was in Industrial Electronic repair, > I ran into this scenario most of the time. One particular motor > controller kept coming back to us as non-functioning, and we never found > a problem with it. We finally decided the unit just like the looks of > the technician, so we took a picture of him and taped it inside the > cover. It shipped back to the customer with evidently never another > trouble. Electronics: BAHHH. > > Health-wise I am much better, but have no stamina. Working on that.... > > Tom Knowles > > On 1/7/2013 4:00 AM, emmettdene wrote: > > > > rubbing alcohol works great for cleaning track. leaves no residue. > > emmet d > > > > --- In yardbirdtrains@... > > , Mike Bauers wrote: > > > > > > Goo Gone cleans and leaves an insulating layer behind. I've used it > > and seen the layout go dead as a result the following morning. > > > > > > Do try any kind of tuner cleaner on those wheels. Or go to one of > > the good hardware stores, auto parts supply stores, or marine supply > > stores and get a can of the electronic cleaner and conditioner you > > find there. > > > > > > Most of the time its a CRC product > > > > > > Advanced Auto Parts has " CRC QD? Electronic Cleaner" for a bit over > > $7 in a large spray can. Wet a Q-tip with it and wipe the driver tires > > and other electrical surfaces with it. > > > > > > You can do the same with your rails [wipe about 6-inches every > > several feet apart then drive around the layout] and you'll see a > > marked operating improvement in a matter of seconds. > > > > > > Do the complete electrical path on the loco's and your track switch > > points and you'll feel like you have gold plated electrical contacts > > on everything. That includes even old zamak slabs that are part of the > > electrical path on old models, treat contact points and any screws > > that are part of the electrical paths. > > > > > > Case in point, it makes an ancient Athearn 0-4-2t Little Monster > > that is largely a zamak electrical path and has sat for 20 years, run > > like a new Kato after that treatment.... that and a wisp of fresh oil > > and axle lube in the right places. This is my personal experience with > > the stuff and that model as well as many others. Models that simply > > never were known to run decently in the first place. > > > > > > Don't overlook places like the body pads under the tender trucks and > > the place where the washer like connector wire goes between the > > locomotive and the tender. Back off such screws and wipe both the > > threads and the contact area under the screw heads and the connector > > 'washer', then snug down to working positions. > > > > > > I'm certain you will be amazed at how much better the model operates > > when you have conditioned the electrical points that have become > > oxidized and thus somewhat insulated over time........ with just a > > certain fluid. > > > > > > Best to ya... > > > Mike Bauers > > > Milwaukee, Wi, USA > > > > > > > > > > > > On Jan 6, 2013, at 12:44 PM, twilight022765 wrote: > > > > > > > John, one of the guys in my earlier posts responded with a product > > he recommends called Flitz, which I just order last night on Amazon. > > My drivers on my H9 are brass(probably worn down to the brass???). I > > have used Goo Gone to clean them. But, as he mentioned about his club, > > my club's rails can get quite dirty and maybe the Goo Gone isn't doing > > the trick anymore. So, I want to give that a try. The reason for the > > question was, my L1, that is set up the same way as my H9 is operating > > rather nicely and has the NS drivers. It's like some one put a > > resistor in line with the motor on the H9. This will be my last try to > > improve the conductivity before I add the pickups. > > > > > > > > Thanks again to everyone who has offered their helpful advice. > > > > > > > > Mark > > > > > > > > --- In yardbirdtrains@... > > , "John Hagen" wrote: > > > >> > > > >> Well I can't say much about brass vs NS but I can speak from > > experience > > > >> about the difference between sintered metal and NS. By actual > > comparison NS > > > >> has comparatively poor adhesion on NS track. > > > >> > > > >> > > > >> > > > >> My "Athearn" Baldwin S-12 with an Cary built (lead-antimony) Cary > > Alco S-2 > > > >> shell along with added lead, a Sagami 2032 motor w/brass > > flywheels and Ernst > > > >> gears was able to easily switch a cut of 56 5 oz. 40 ft. freight > > cars, all > > > >> with C.V. trucks on my friends (Cal) layout. After the switch to > > NWSL NS > > > >> wheels it hard a hard time moving anything over 40 of the cars in > > the yard. > > > >> That coincided with Cal's change to Command Control but that > > really had > > > >> nothing to do with it as the problem was wheel slip. > > > >> > > > >> > > > >> > > > >> Although not a direct comparison, my thoughts are that brass > > wheels would > > > >> have similar traction to the sintered metal. Having started on HO > > around > > > >> 1949 I have much experience with brass drive wheels. > > > >> > > > >> > > > >> > > > >> So far as cleanliness if one's track is clean kept brass and > > sintered metal > > > >> work just fine. So far as electrical pick-up all will work okay > > but I agree > > > >> that NS gets a bit of the nod here. A more important > > consideration to me is > > > >> having reasonable clean rail without being so clean and dry that > > arcing is > > > >> promoted. > > > >> > > > >> > > > > > > > > |
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开云体育Please trim your replies. ? John Hagen ? From: yardbirdtrains@... [mailto:yardbirdtrains@...] On Behalf Of emmettdene
Sent: Tuesday, January 08, 2013 4:42 AM To: yardbirdtrains@... Subject: [yardbirdtrains] Re: Driver surfaces ? Brass or NS ? ? ?
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