Atlas SD35

[rrjim1]

I don't see how this design added weight over the contact strip method. Also what is up with that large step down at the rear of the chassis? They could have added a LOT of weight there.

I don't believe anyone said it added weight over the original, if you look at the OP it states .1 oz less. If you consider the weight removed for the speaker than it helped bring the weight up closer to the original. 

[jdcolombo]

I don't see how this design added weight over the contact strip method. Also what is up with that large step down at the rear of the chassis? They could have added a LOT of weight there.

YES!  Although I like the fact that this is there for two reasons.  First, if I want to add weight, it's a perfect place for some tungsten, which probably would get you considerably more weight than using original chassis material - some bundled tungsten rod, for example.

OR . . .  if I get one of these and decide I could do better sound-wise with a speaker mounted up top, that "shelf" gives me a perfect place to do it.  And then I can fill in the speaker hole in the gas tank area with lead (have to be careful not to short the frame, but that shouldn't be too hard - wrap the lead in kapton tape).

John C.

[wmcbride]

I don't need an SD35, but I might get one anyway just to see how this was done.  Glad that the sound is good.  Does the speaker fire up into the chassis or down through the fuel tank toward the track? 

John C.

John,

You need a "NKP" SD35...

I was brave and pulled the tank off; very tight press fit. Here's what's underneath:

[peteski]

The reason Atlas removed the frame pickup strips and screws was to add weight to the frame and leave more room for the speaker. If Atlas used good flexible wire its sure looks like a better design, very little movement with a solid connection.  IMO job well done Atlas.

Regardless of how flexible the wires are, I'm of the same school as Victor Miranda, and generally not a fan of wires inside models. Especially when they are not a part of a static wire harness, but used to interconnect constantly moving parts (like trucks to the frames).  They also complicate and hinder easy model disassembly. Model designers usually try hard to eliminate wires and simplify model assembly/disassembly. It is sad to see us going back to using wires.  We don't need more Yugoslavian Mechanic models from the '70s. Yes, I know that these are better made than those Yugos, and use better wire, but my point still applies.  There should be no reason for truck pickup wires, especially in a model which could easily be produced using the conventional and proven wire-less design.

And as quoted above, you (unintentionally?) stated that wires were added "to add weight to the frame and leave more room for the speaker". Your won words.  But you failed to notice that there are there are areas of frame carved out for the wire - those reduce the frame's weight.   

[soo]

The next 64$ question,,,can these new frames with sound be used for the SD7/9?. Heck maybe the SD24/26?

Laters,
Y-it

[wmcbride]

I sanded off the nub in the "old" SD35 shell (left). The shell fits better on the new Loksound chassis but there is still something toward the front that is keeping the cab end high. I'll try to measure the height of the chassis / decoder assembly on each version.

[rrjim1]

Regardless of how flexible the wires are, I'm of the same school as Victor Miranda, and generally not a fan of wires inside models. Especially when they are not a part of a static wire harness, but used to interconnect constantly moving parts (like trucks to the frames).  They also complicate and hinder easy model disassembly. Model designers usually try hard to eliminate wires and simplify model assembly/disassembly. It is sad to see us going back to using wires.  We don't need more Yugoslavian Mechanic models from the '70s. Yes, I know that these are better made than those Yugos, and use better wire, but my point still applies.  There should be no reason for truck pickup wires, especially in a model which could easily be produced using the conventional and proven wire-less design.

And as quoted above, you (unintentionally?) stated that wires were added "to add weight to the frame and leave more room for the speaker". Your won words.  But you failed to notice that there are there are areas of frame carved out for the wire - those reduce the frame's weight.   

You failed to see why Atlas removed the frame strips, bigger speaker, better sound, very close to original weight. Even with the larger area cut out for that large speaker Atlas still kept the loco close to the original locos weight. I guess those small carved out areas didn't make much of a difference, kind of hard to install wire there with out them. I will gladly put up with the wires for a better sounding loco. IMO it a win for Atlas.   

[peteski]

You failed to see why Atlas removed the frame strips, bigger speaker, better sound, very close to original weight. Even with the larger area cut out for that large speaker Atlas still kept the loco close to the original locos weight. I guess those small carved out areas didn't make much of a difference, kind of hard to install wire there with out them. I will gladly put up with the wires for a better sounding loco. IMO it a win for Atlas.

As usual, I'm again sorry  to  fail to see things your way.    We are obviously like a Yin and Yang of model railroading. Happy modeling!

[wmcbride]

I've made some measurements, trying to be as accurate as I could be, with measurements #2 and #3 being less useful to fitting the old shell.

1. Height from chassis bottom (in way of cab-end truck) to top of highest circuit board component

New Loksound SD35:   18.46 mm
Old factory DCC SD35   18.12 mm

2. Height from bottom of ties of ME C55 flex to top of highest circuit board component

New Loksound SD35:   30.8 mm
Old factory DCC SD35   30.1 mm

3. Height from bottom of fuel tank to top of highest circuit board component

New Loksound SD35:   26.85 mm
Old factory DCC SD35   26.21 mm

[wmcbride]

... and you know what I'm going to do after all these measurements and photos? Just run them as they came from the factory and keep my old units intact. Ha!

[jdcolombo]

John,

You need a "NKP" SD35...

Yeah.  What the heck; if they'd lasted another couple of years, they probably would have had some.

It looks like Atlas did this right - bottom area is sealed off, with speaker firing upward into the shell, which will give a bit more reverb and "deepen" the sound.  Still suspect the actual enclosure isn't big enough, but if it sounds good, all is well.

John C.

[wmcbride]

Yeah.  What the heck; if they'd lasted another couple of years, they probably would have had some.

It looks like Atlas did this right - bottom area is sealed off, with speaker firing upward into the shell, which will give a bit more reverb and "deepen" the sound.  Still suspect the actual enclosure isn't big enough, but if it sounds good, all is well.

John C.

John,

A larger enclosure would have helped but at least the sounds are acceptable and good as is unlike the Scale Trains Tier 4.

You've shown what good sound can be in N scale and my installations inspired by your teachings have become my benchmark for what I want.

Maybe you should order your "NKP" SD35 today while MB Klein has free shipping. Given the factory upheaval in China who knows if we will ever see another SD35 shipment (or much else) for years...

[jagged ben]

Spookshow has a review up, with some additional pictures. According to him, the truck wires are connected to metal pins that just pull out of the chassis.  I actually just bought his review model on eBay (thanks Mark!), so just going off his info but there you go.

It appears to me that perhaps the reason we no longer have the traditional contact strips is that they would pass through part of the physical space that now contains the speaker.

[daniel_leavitt2000]

I still think they could have gone with pickup strips. If not full length contacts, smaller  contact strips located at the ends of the chassis (like the LL SW1200 but mounted to the chassis.

[jagged ben]

I still think they could have gone with pickup strips. If not full length contacts, smaller  contact strips located at the ends of the chassis (like the LL SW1200 but mounted to the chassis.

I agree.   Just pointing out that maybe it's not just because 'someone wanted to do things differently'.