Stripped Down IM SD40-2 with ESU Loksound

[carlso]

I want to preface this thread by saying that in no way am I attempting to throw flames at IM. I think they did a good job with the Ferromex version that I got. Looks great, sounds good, needs some tweaking for sound and drive train. It runs slower than any Atlas or IM scale speed motor that I have seen or had. I decided to go inside to see what I could find. There are 14 jpeg's that I will most likely have to put in 2 or 3 posts. I just want to share the facts with anyone interested, so here goes :

Shell off of chasis


Naked as the day she was born




Here is the anti short device that is under the decoder


I was attempting to show the large amount of grease or oil on the plastic as well as on the top of chassis


Speaker contacts on left, motor tab contacts on the right


Here is an image that is sort of telling a story. You can see dirt and grease in the gear tower area as well as some shiny spots that would indicate something from the drive shafts may be rubbing


After posting the last photo, I studied it and the two frame 1/2's. You can see, on each end of frame a circle that must be something from the mold, assuming these are poured and not milled. At any rate I checked the drive shafts and found that indeed they both had rubbed at the u-joint just in front of inside worm bearing. Not too bad as I have not run it much.

More to some.

Carl

[carlso]

 Now comes the nastier part.

This pic is not bad. You are looking at how the mechanism sits in the right side frame as well as the speaker sitting in fuel tank area


Trying to show the grease around the flywheel and drive shaft connection. Why there ? ?


Totally uncalled for


As info, here is the speaker set up. First is the bottom of the enclosure showing a few holes venting up into the frame as well as the 2 speaker contacts


Here is the speaker, it fires up through the frame via the back side of speaker. The bottom of speaker is not open


The next two are both of the top side of motor and cage. Keep in mind left side contacts are speaker and right are motor tabs. Actually the top side or right side of motor tab is skewed a bit




Everything considered, I feel that this IM production is quite nice and look forward to putting it back together. Then I can fine tune the sound volumes and all and also the motor control.

I hope there is some value for you and thanks for looking.

Carl

[peteski]

Nice evaluation Carl!
The motor and mechanism looks very similar to typical Atlas/Kato/FVM/etc. construction.  I think that the ESU decoder is the reason for that excellent slow speed. They have excellent motor control.  I have a feeling that if you took the decoder out and and compared it to a DC-only Kato or Atlas loco of similar construction, they would all have similar low-speed performance.  I think these locos even use Atlas trucks (I know other IM locos shared parts with Atlas).

I'm also surprised that there are several milled out areas in the chassis. Usually the molds are designed without need to mill out anything. Seems that someone messed up the design and they have to mill every frame to get it to the correct dimensions.  The extra steps likely add to the cost of the model (unless the factory messed up and is eating the extra cost of machining). I know that this does not affect the model's performance, I just found it surprising so I commented on it. 

[u18b]

Hi Carl.
Thanks for posting.

I think you are mistaken about the shaft possibly rubbing a spot on the frame.

If you look at this photo-- notice the marks are circular.


What you are looking at are the casting marks on the frame.  What you were thinking is a problem (shiny spots) is actually the IM factory people doing a good job of smoothing the burrs down after casting the frame pieces.

Assuming of course all is flat.   Are you thinking that there are projections of metal?

Or were you just noticing that it was shiny in that spot?

What I find MORE curious is the gear tower opening.
One side is normal (looks unmodified- unless I'm mistaken and grease is covering the shiny-ness), the right side in your photo is shiny.

[carlso]

Thanks Ron for your input. I very much appreciate your skills.

In regards to the shiny spots that I think indicated something rubbing I will have to disagree with your assessment. The round spots are the casting marks and were relatively deep, so deep in fact that when rubbing with my finger had I applied a little pressure they would have scratched the skin. There was what looked like flashing, albeit small, around the circle. Also after examining the drive shaft u-joint I found very small bits of delrin that may have been flashing as well and possibly that is what rubbed. I see no evidence of anybody attempting to smooth them out. So, I have done so. Here are a couple more images :

Both frame 1/2's, you can see the rough edges around the casting marks. You will also note that after cleaning with 91% alky the frames look alike particularly in the gear tower area. The opening of the gear towers obviously have been milled most likely to remove flashing .


For grins here is the chassis, shows milling on left side above the flywheel hole as well as the square for the notor cradle, with contacts, to protrude. Some milling between the lugs on top side. Also on the right,front end, of them have been milled some.


My smoothing of the cast marks, also shows the speaker hole, in fuel tank area, was cast as opposed to milled out.


As I have said this is a good model and would purchase another IM with ESU sound. My only concern is that I will not be able to make this consist and run well together with my FVM Gevo's in Ferromex paint because I replaced the FVM motors with KATO motors when first received. Oh well, I'll try.

Thanks for looking and the comments,
Carl

[Mark5]

My only concern is that I will not be able to make this consist and run well together with my FVM Gevo's in Ferromex paint because I replaced the FVM motors with KATO motors when first received. Oh well, I'll try.

Thanks for looking and the comments,
Carl

Why did you do that? Kato motors run on the fast side - were you hoping to run them in DC with other Katos?

Mark

[peteski]

Carl, could you post a photo of the frame half with an arrow or some other mark pointing where the universal coupling cup rubs against the frame?  I have hard time seeing any marks, and the other photo which shows the frame half with the worm and shaft installed seems to show plenty of clearance around the coupling cup.

As far as the speed matching goes, with ESU and with DCC in general, matching different speed locos should not be very difficult.  Assuming that you don't expect perfection (which is IMO pretty much an impossible task, even with identical models).

[carlso]

Mark,

I did that because I had 2 FVM's and 10-12 Kato's. Much less expensive to change 2 vs. several. Since then I have DCC and I hope I can fine tune this new slow motor to run with the FVM Ferromex units that I have put KATO motors into. BTW, KATO only runs fast if the throttle is opened too much. Not necessary to do that at all.

carl

[u18b]

Thanks Ron for your input. I very much appreciate your skills.

In regards to the shiny spots that I think indicated something rubbing I will have to disagree with your assessment. The round spots are the casting marks and were relatively deep, so deep in fact that when rubbing with my finger had I applied a little pressure they would have scratched the skin. There was what looked like flashing, albeit small, around the circle. Also after examining the drive shaft u-joint I found very small bits of delrin that may have been flashing as well and possibly that is what rubbed. I see no evidence of anybody attempting to smooth them out. So, I have done so. Here are a couple more images :


Thanks for looking and the comments,
Carl

Sorry.   I mis-understood.  If there are black particles from rubbing, then that is not good.

Thanks.

[carlso]

Pete,

Here is the image that indicates rubbing. I am not sure what was making the marks but something sure did. The cast mark on the left had enough of a ridge (flashing ?) that you can see at the 1st quadrant of the circle, plus a bit of shadow at approx 10 on the left side. The shiny marks are very noticeable on the right side. I do not know what was rubbing but I did find some small bits of delrin that may have been flashing on the universal cup. BTW, the area marked and the shadow areas were very jagged with flashing. At any rate I smoothed out the cast marks on both frame 1/2's and cleaned everything with 91% alcohol and cleaned the wheel treads by running over 1,000 grit wet/dry paper to remove any and hopefully all of the blackening applied by factory. I reassembled and have test run on my bench. It appears to run smoother and more responsive. I will test on layout next Wednesday.



I was able to re-map the sounds and tweak volumes and am pleased with the results. The unit is a real nice looking, detailed, and very well painted, so I am happy with it. IM/ESU collaborated well on this project and hopefully on subsequent releases as well.

Thanks for all the input,
Carl

[peteski]

Pete,

Here is the image that indicates rubbing. I am not sure what was making the marks but something sure did. The cast mark on the left had enough of a ridge (flashing ?) that you can see at the 1st quadrant of the circle, plus a bit of shadow at approx 10 on the left side. The shiny marks are very noticeable on the right side. I do not know what was rubbing but I did find some small bits of delrin that may have been flashing on the universal cup. BTW, the area marked and the shadow areas were very jagged with flashing. At any rate I smoothed out the cast marks on both frame 1/2's and cleaned everything with 91% alcohol and cleaned the wheel treads by running over 1,000 grit wet/dry paper to remove any and hopefully all of the blackening applied by factory. I reassembled and have test run on my bench. It appears to run smoother and more responsive. I will test on layout next Wednesday.



I was able to re-map the sounds and tweak volumes and am pleased with the results. The unit is a real nice looking, detailed, and very well painted, so I am happy with it. IM/ESU collaborated well on this project and hopefully on subsequent releases as well.

Thanks for all the input,
Carl

Thanks Carl.  That photo is a bit small and fuzzy.  You also posted earlier photo showing the drivetrain parts in that frame half.  Did you observe that the clearance between the drivetrain ports and the shiny areas was very tight? Tight enough to have those parts rubbing the frame?  The photos seem to show that there is ample clearance in that  area unless the warm bearings have *LOTS* of side-to-side play when the model is assembled.  Another thing that puzzles me is how soft plastic rubbing against metal would cause such visible shiny marks.  I would expect much less obvious markings.  Then of course is the additional noise which should be audible when the rubbing occurs. 

I guess I would have to have the model in-hand for a super-close view to be able to evaluate what those marks are.  I'm not trying to prove you wrong - I would just like to figure out exactly what is going on.  To me those marks look like they could have been made by a small sanding drum in a rotary tool used by worker removing flash from the ejector-pin areas.  But they simply "kissed" those areas without doing really good job smoothing out the sharp edge of the ejector-pin mark. These are done on an assembly line and the person is doing hundreds of them, so I can see them not doing a really through job. Or maybe they just had a bad day.

Basically, I'm agreeing with Ron's opinion.

[carlso]

Thanks Pete.

Carl

[Steveruger45]

Hello Carl
I am a little late reading this thread but I have two IM deuces and worked on four others and had all six apart to install capacitors. I too noticed the casting marks you mention.  They are, I think, actually the remains of removed casting risers which are used in molds to allow additional molten metal to be poured in and to be sure the pour gets to all the nooks and crannies of the mold by maintaining a slight head and to allow for metal shrinkage on cooling.  Of course I have no idea how they make these exactly as they could also be die-cast and these marks are from that process when removed from the dies.  Basically I’m agreeing with Ron and Pete.
Anyhow, I too Noted the mechanical like polishing marks that I too assumed was the factory dressing up the Remaining flash or spruce at these locations.  One was not done as well as the other five and indeed did slightly touch the drive train. I too spent some time polishing these a bit better than the factory did.  BTW you might also want to consider taking the trucks apart and polish up the dimpled wheel contact strips as well. I found these covered in some black or silver colored coating. Also the decoders, in about 50% of the ones I looked at, were loose in the frame slots, causing intermittent contact.  After cleaning all the goop/grease out, polishing the frame in way of casting risers or die eject marks, polishing the trucks dimpled contact strips and tightening up the slots for the decoder contact with the frame they all run flawlessly.

BTW does anyone know if the dc only versions of these locos has the speaker installed?
Thanks

[bman]

BTW does anyone know if the dc only versions of these locos has the speaker installed?
Thanks

My DC and and DCC only(no sound) versions do not have speakers. The area to mount the speaker in the frame in the fuel tank area is present though.

[Steveruger45]

My DC and and DCC only(no sound) versions do not have speakers. The area to mount the speaker in the frame in the fuel tank area is present though.

Appreciate the reply.  So upgrading to sound is not just a simple swap out of the decoder.