Best Of *Science* of solving N scale diesel mechanism drivetrain vibration noise?

[u18b]

I use two wires with alligator clips on both ends.

One end to the track rail, the other to the frame.

[atsf_arizona]

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Downloadable Excel spreadsheet cross-indexing some major Atlas diesel components!  
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One of our the major discussions has been:

• What are the correct replacement part numbers to use in these locomotives?
• What parts are swap-able between locomotives?
  (focusing on motors, motor saddles, worm/shaft assemblies, bearing blocks, trucks)
  

To answer that question, I collected the part number information from the Atlas and Intermountain parts websites, and created an downloadable Excel spreadsheet which has drop-down Sort menus allow you to find and correlate part numbers across almost all the N scale Atlas/Kato, Atlas, and Intermountain SD45-T2 / SD40-T2 locomotive types. 

This allows you to answer for yourself :

*By locomotive type,  what part number for  motor, motor saddle, trucks, etc?

What became apparent when building this spreadsheet, is there are some notable "exceptions" to what you would expect to be a compatible part. 

• Example:  according to the instruction sheets, the DCC-ready Atlas GP30/35, GP7 and GP9 use a different motor saddle than the commonly used p/n 480001.  I verified and found this to be true in a Atlas 48082 Santa Fe GP7 #2692 some time ago.  I swapped in a older fast-speed motor into that GP7 DCC-ready mech, to speed match the loco with my older fleet - and found that the standard motor saddle p/n 480001 plastic fingers are spaced *differently* than the GP7 DCC-ready mechanism motor saddle holes.  I had to "force fit bend the plastic fingers" to match the GP7 DCC-ready mechanism (at the time, I had no idea these particular newer DCC-ready mech's used a different motor saddle).

These exceptions are especially worth knowing to save time and effort, not to mention possibly being cause of a hard-to-shoot bug in a noisy locomotive mechanism.

Here's screen shots of the spreadsheet, sorted by locomotive.  (Downloadable link is at bottom of this post). 

The bolding and colored cells are some of these 'unexpected exceptions' to the part number you would expect to be compatible.

(P.S.  Updated the Google Drive spreadsheet copy on 12/22/19 to reflect new URL prefix that Atlas started using for the PDF parts diagrams, compared to the screenshot)







============================================================================


Very useful are the "Sort" drop-down headings at the top of the Excel spreadsheet, by sorting "A->Z", you can quickly find out:

* What parts are swappable between what locomotives? 

Example:  this shows the spreadsheet sorted by the truck number:



===========================================================


Here is the clickable link from Google Drive to download Excel spreadsheet, click on the link and download it for free - you are welcome to share it.

(2019 12 22 - updated the Google Drive link below as the old link didn't work any longer - this should allow you to download the Excel file)
(8:40PM EST 12/22/19 - uploaded additional new version that fixed the URLs to point to Atlas' new location of loco Parts diagrams)

https://drive.google.com/file/d/1A6VJR3uFGOLfr50-GreWia_oe4UCCxaL/view?usp=sharing

Instructions: 

You must "Open with Google Sheets", or download it to your Excel on your Windows PC or Mac and then "Enable Editing", in order to see the drop-down menus.

I trust that you'll like this resource. 

It's a best-effort, I believe it's as accurate as the info that I have.  With so many part numbers, I do find 'inconsistencies' such as the following:

• Motor saddle p/n 426001 is specified for both Atlas RS-11 Classic, and on the parts sheet for GP9 DCC-ready.  But "not found" on Atlas Online Parts website.  (neither p/n 9426001 nor p/n 426001 were found).
• No parts diagrams on Atlas Parts website for GP7/GP9 DCC-ready, or the VO-1000.

I documented this info off the PDFs on the Intermountain website at:   http://www.intermountain-railway.com/customerservice/dccwebpage/N-Scale-SD40T-2-SD45T-2-Insert.pdf  and the Atlas parts website at:  https://shop.atlasrr.com/t-partsdiagrams.aspx  I then then cross-checked the 'exceptions' at the Atlas Online Store at https://shop.atlasrr.com/c-1064-n-locomotive-spare-parts.aspx  .   Not all 'parts not found on Atlas website' or inconsistencies could be resolved, but thankfully, there's very few inconsistencies  (so congrats to Atlas for such a great Parts website). 

Regardless, this whole spreadsheet should help up-level our "parts" conversation significantly.

Yes, it's taken a long time to put all this together.  It's best-efforts basis and not guaranteed to be 100% correct (or updated if a manufacturer updates and I don't know about it).  It'll be continuing work in progress and I enjoy doing it if time allows.  The spreadsheet is update-able.  When I have time, perhaps I can add the Kato parts, as well as other useful parts such as "universal joints" or "PC boards".   

But now that the 2016 Holidays are almost over...... those updates will wait for time availability.

Comments and suggested corrections welcome.

You are welcome to share it.... all I ask is that you give me credit as the original author.

[cjm413]

This thread deserves "Best Of" status

[BCR751]

Those are some vintage multimeters Doug!  Bakelite cases an all . . .  they probably have jeweled movements too! I love it. Those are even older than the old Simpson multimeter I used in my first job as an electronic technician.

Well, if you want the best you gotta dig deep  .  I've had these things for a lot of years.  Just could never get rid of them and now I'm glad I didn't.  The old US Navy meter on the left is a bit ungainly and weighs a ton but it does just about everything, including very high voltage measurements with the multiplier kit on top.  It requires 11 "D" cells for resistance measurements.  Definitely not for the faint of heart  but it sure does look cool

I like Jagged Ben's idea.  Much better protection for the board, decoder etc.

Doug

[cjm413]

---------------------------------------------------------------------------------------------------------
Downloadable Excel spreadsheet cross-indexing some major Atlas diesel components!  
---------------------------------------------------------------------------------------------------------

One of our the major discussions has been:

• What are the correct replacement part numbers to use in these locomotives?
• What parts are swap-able between locomotives?
  (focusing on motors, motor saddles, worm/shaft assemblies, bearing blocks, trucks)
  

To answer that question, I collected the part number information from the Atlas and Intermountain parts websites, and created an downloadable Excel spreadsheet which has drop-down Sort menus allow you to find and correlate part numbers across almost all the N scale Atlas/Kato, Atlas, and Intermountain SD45-T2 / SD40-T2 locomotive types. 

This allows you to answer for yourself :

*By locomotive type,  what part number for  motor, motor saddle, trucks, etc?

What became apparent when building this spreadsheet, is there are some notable "exceptions" to what you would expect to be a compatible part. 

• Example:  according to the instruction sheets, the DCC-ready Atlas GP30/35, GP7 and GP9 use a different motor saddle than the commonly used p/n 480001.  I verified and found this to be true in a Atlas 48082 Santa Fe GP7 #2692 some time ago.  I swapped in a older fast-speed motor into that GP7 DCC-ready mech, to speed match the loco with my older fleet - and found that the standard motor saddle p/n 480001 plastic fingers are spaced *differently* than the GP7 DCC-ready mechanism motor saddle holes.  I had to "force fit bend the plastic fingers" to match the GP7 DCC-ready mechanism (at the time, I had no idea these particular newer DCC-ready mech's used a different motor saddle).

These exceptions are especially worth knowing to save time and effort, not to mention possibly being cause of a hard-to-shoot bug in a noisy locomotive mechanism.

Here's screen shots of the spreadsheet, sorted by locomotive.  (Downloadable link is at bottom of this post). 

The bolding and colored cells are some of these 'unexpected exceptions' to the part number you would expect to be compatible.







============================================================================


Very useful are the "Sort" drop-down headings at the top of the Excel spreadsheet, by sorting "A->Z", you can quickly find out:

* What parts are swappable between what locomotives? 

Example:  this shows the spreadsheet sorted by the truck number:



===========================================================


Here is the clickable link from Google Drive to download Excel spreadsheet, click on the link and download it for free - you are welcome to share it.

https://drive.google.com/open?id=0B5CoS45LdyoKVWVuMWFjaHN0NDQ

Instructions: 

You must "Open with Google Sheets", or download it to your Excel on your Windows PC or Mac and then "Enable Editing", in order to see the drop-down menus.

I trust that you'll like this resource.  It's a best-effort, I believe it's as accurate as the info that I have.  I documented this info off the PDFs on the Atlas parts website at:  http://www.atlasrr.com/nparts.htm   and then cross-checked the 'exceptions' at the Atlas Online Store at:   http://shop.atlasrr.com/c-1064-n-locomotive-spare-parts.aspx

Comments and suggested corrections welcome.

You are welcome to share it.... all I ask is that you give me credit as the original author.

Another column to consider adding could list compatible parts from other locomotive models, e.g. the previously-referenced Kato wheelsets for the Atlas and IMRC HT-C trucks, Kato's SD40/45 Flexicoil truck sideframes that fit Atlas SD35 trucks and vice versa (for the purpose of matching a specific prototype rather than to address any performance issues with either mechanism), etc.

[atsf_arizona]

Another column to consider adding could list compatible parts from other locomotive models, e.g. the previously-referenced Kato wheelsets for the Atlas and IMRC HT-C trucks, Kato's SD40/45 Flexicoil truck sideframes that fit Atlas SD35 trucks and vice versa (for the purpose of matching a specific prototype rather than to address any performance issues with either mechanism), etc.

Thx, cjm413, agreed.

This spreadsheet will continue (always?!) be a work in progress.  I don't mind doing it - when I have time, perhaps in addition to your suggestions, I can add other Kato parts, as well as other useful parts such as "universal joints" or "PC boards".   

The downloadable Excel spreadsheet is updateable.  If anyone cares to add and populate a column and wants to send me your updated copy, I'm happy to integrate that new info back into the spreadsheet that is sitting at the Google Drive URL,  as my time allows.  (No guarantee on when).

But now that the 2016 Holidays are almost over...... those updates will have wait for time availability.... time to get back to work.

Comments and suggested corrections continue to be welcomed.  I hope you find the spreadsheet as useful as I have.

2019 12 22:  Updated Google Drive link to this spreadsheet:
https://drive.google.com/file/d/1A6VJR3uFGOLfr50-GreWia_oe4UCCxaL/view?usp=sharing

[Big Train]

Great work, atsf_arizona!

Can I suggest the addition of frame numbers for each model? Might be useful when working on Atlas GP7/9, early Atlas RS and RSD, early Kato.

When the manufacturers started producing the DCC Friendly frames I'm sure there would be multiple frame part numbers for each model. For example, I know the first run Atlas SD7/9 shells won't fit the newer SD7/9 DCC Friendly frames.

Just an idea....

Cheers!

[cjm413]

Thx, cjm413, agreed.

This spreadsheet will continue (always?!) be a work in progress.  I don't mind doing it - when I have time, perhaps in addition to your suggestions, I can add other Kato parts, as well as other useful parts such as "universal joints" or "PC boards".   

The downloadable Excel spreadsheet is updateable.  If anyone cares to add and populate a column and wants to send me your updated copy, I'm happy to integrate that new info back into the spreadsheet that is sitting at the Google Drive URL,  as my time allows.  (No guarantee on when).

But now that the 2016 Holidays are almost over...... those updates will have wait for time availability.... time to get back to work.

Comments and suggested corrections continue to be welcomed.  I hope you find the spreadsheet as useful as I have.

A similar list would also be useful for diesel shells - for example, I saw a reference to an Atlas Dash-2 cab (don't recall which one) as a replacement for an Intermountain SD45-2 cab on a different thread.   On that note, there are parts that aren't as compatible as one would expect such as the Atlas GP38-2 cab and Atlas GP40-2 cab.

[atsf_arizona]

Great work, atsf_arizona!

Can I suggest the addition of frame numbers for each model? Might be useful when working on Atlas GP7/9, early Atlas RS and RSD, early Kato.

When the manufacturers started producing the DCC Friendly frames I'm sure there would be multiple frame part numbers for each model. For example, I know the first run Atlas SD7/9 shells won't fit the newer SD7/9 DCC Friendly frames.

Just an idea....

Cheers!

Good suggestion, agreed, would be good to add.   

[u18b]

For those of you who may have never read my article on how to remove the inner bearing block to make many locos very very quiet...

Here it is:

http://southernmodeler.info/Bearingblock.pdf

You may want to bookmark this.  It is a new address.
Thanks to Jerry Laboda for hosting this file for probably about 10 years (I've always been curious how many times it had been accessed).

The same file is on my U18B.com website, but unfortunately I have bandwidth issues sometimes.
That's why Jerry's site is a good back up.

If you have never ever tried this procedure, I cannot recommend it enough.

EDIT:  the link above does not work in 2020.
Here is the direct link to my website:
http://u18b.com/wp-content/uploads/2019/10/Bearingblock09.pdf

[atsf_arizona]

For those of you who may have never read my article on how to remove the inner bearing block to make many locos very very quiet... here it is:

http://southernmodeler.info/Bearingblock.pdf

If you have never ever tried this procedure, I cannot recommend it enough.

Ron Bearden,

Thank you not only for your 4-axle loco bearing block technique above, but also your expertise in pointing out in replies #74 and #102, that the gear teeth "bottoming out" against the worm gear is also a significant source of noise.

Armed with that information, I realized by doing the vertical up/down test while the mechanism was running (powered by alligator clips), that the swapped-in C628 truck's *tower gear* was bottoming out on the Atlas B40-8 mechanism's *worm gears*.

I realized I needed to create further space to "lower the tower gear relative to the worm", thus I needed to grind out further the mounting notch:



And then super-glued shims on the bottom of the mounting pads (.005" on one and and .010" on the other were found to be sufficient).  This is the mounting pad just below the black arrow in the photo above (the photo doesn't show the super-glued-on shims.

Result:    the C628 truck tower gear no longer bottoms out on the worm gear, and this is the result - amazingly quiet:

/>
Compare this video with the extremely noisy mechanism that it used to be:  http://www.tubechop.com/watch/8728439   Huge difference!

So, in addition to the "4-axle loco remove inner bearing block technique", we need to add the Ron Bearden "make sure tower gear is *not* bottoming out on worm gear" is added to our list of problem determination techniques.

[peteski]

John,
I found a GREAT benefit to drilling a hole in the area over the worm gear so that I could SEE the gear mesh.

You can see that I was able to adjust the worm on my brass EP-2 so that just a little daylight is between the tips of the teeth and the bottom of the worm.

The same thing could help you since you are making mods that effect this interface.

Yes, this is an excellent idea: a viewing port for the worm gear!

What I found amusing is that not long after I read your post I was servicing some older Atlas/Kato chassis (SD45 or SD40?) for a friend and they have factory-made hole exactly in that spot - you can observe how the worm meshes with the worm gear.  There might be other chassis of similar vintage which also have that viewing port.  I also remembered that back when these were new and I took the apart I was wondering what that hole was for.  Now I know. 

[cjm413]

Ron Bearden,

Thank you not only for your 4-axle loco bearing block technique above, but also your expertise in pointing out in replies #74 and #102, that the gear teeth "bottoming out" against the worm gear is also a significant source of noise.

Armed with that information, I realized by doing the vertical up/down test while the mechanism was running (powered by alligator clips), that the swapped-in C628 truck's *tower gear* was bottoming out on the Atlas B40-8 mechanism's *worm gears*.

I realized I needed to create further space to "lower the tower gear relative to the worm", thus I needed to grind out further the mounting notch:



And then super-glued shims on the bottom of the mounting pads (.005" on one and and .010" on the other were found to be sufficient).  This is the mounting pad just below the black arrow in the photo above (the photo doesn't show the super-glued-on shims.

Result:    the C628 truck tower gear no longer bottoms out on the worm gear, and this is the result - amazingly quiet:

/>
Compare this video with the extremely noisy mechanism that it used to be:  http://www.tubechop.com/watch/8728439   Huge difference!

So, in addition to the "4-axle loco remove inner bearing block technique", we need to add the Ron Bearden "make sure tower gear is *not* bottoming out on worm gear" is added to our list of problem determination techniques.

"Alligator clips" do seem appropriate for a RSD-15

[atsf_arizona]

Yes, this is an excellent idea: a viewing port for the worm gear!

What I found amusing is that not long after I read your post I was servicing some older Atlas/Kato chassis (SD45 or SD40?) for a friend and they have factory-made hole exactly in that spot - you can observe how the worm meshes with the worm gear.  There might be other chassis of similar vintage which also have that viewing port.  I also remembered that back when these were new and I took the apart I was wondering what that hole was for.  Now I know. 

Interesting, peteski.   Could you post a picture of the mechanism's  "viewing port"?  I've never seen a Atlas / Kato chassis with such a port.

I'm wondering if someone had drilled the hole. 

Would be great to see exactly where on the chassis it is, to document for all of us where we'd need to add a "worm gear viewing port" if necessary.   

[peteski]

Interesting, peteski.   Could you post a picture of the mechanism's  "viewing port"?  I've never seen a Atlas / Kato chassis with such a port.

I'm wondering if someone had drilled the hole. 

Would be great to see exactly where on the chassis it is, to document for all of us where we'd need to add a "worm gear viewing port" if necessary.   

The model is an older Atlas/Kato SD7 and viewing port (hole) is exactly where the worm and work gear mesh (just like in Ron's model). It was not drilled by someone - it was molded in the chassis.  I seem to recall that other models had a similar hole molded in the chassis, but I don't recall which models. I wonder why they stopped doing that on later models. Here's a photo of the chassis and the insert shows the view through the hole.

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