Got more than one junk Arnold S2?

[LV LOU]

Just messing around,trying to make a mold for Arnold S2 gears to try to fix a pair I have.I have probably a half dozen nice,custom painted ones with NWSL wheelsets,but these are just too rough to spend any kind of money on..I just noticed,the truck idler gears are the same as the axle gears!! So,if you have more than one scrapper,you can fix one with the idler gears from the other..One suggestion,though,ream the holes out a little,they're REALLY tight,if you put them on as is,you'll crack them,too..I'm gonna see exactly what drill size is perfect for it..

[mmagliaro]

Sorry Lou, no can do.  My only two S2's have upgraded gears and wheels, and the gears I pulled out are
all bad.  I had a good run there, when seemingly none of my gears cracked, and then they all went.
So I don't have any junker S2's.

[LV LOU]

Hi Max!  Not really looking for gears,just sharing..I had extra trucks,so I used the gears to fix the two I had.Now I just need to make cabs.I have RS1 and V0-1000 cabs,just gonna kitbash them together.
  I used a #64 bit to punch out the new gears so they won't crack.I also cut down the flanges.They run great.Gonna paint them EL.
  These things were just designed terribly.You look at the trucks,the quality of the stuff looks great,but they goofed up on the shafts.The pins for the idler gears are .033,the axles are .0385.The difference is just too great for it to work using the same gear on both shafts..

[u18b]

Just messing around,trying to make a mold for Arnold S2 gears to try to fix a pair I have.I have probably a half dozen nice,custom painted ones with NWSL wheelsets,but these are just too rough to spend any kind of money on..I just noticed,the truck idler gears are the same as the axle gears!! So,if you have more than one scrapper,you can fix one with the idler gears from the other..One suggestion,though,ream the holes out a little,they're REALLY tight,if you put them on as is,you'll crack them,too..I'm gonna see exactly what drill size is perfect for it..

Yep... I suggested that years ago in an article.

By the way.... if you are going to make castings..... fix the weak spot!

The whole reason these things crack is a design flaw.  There is a dimple for the injection sight for the spru when they are made.  These gears ALWAYS crack at that dimple.

Soooo.......  if you are making castings, then body putty your dimple on the master so that your castings do not have the SAME flaw.

[u18b]

Here you go....

Use the link:  http://www.trainboard.com/railimages/data/500/s2_gears.png

Since the pic is so large.

This was the chart where I placed the cracked gear (repaired) as an idler gear and place a new fresh idler gear as an axle gear.

Not the best solution,  but the diagrams fit the current discussion.

[LV LOU]

Yep... I suggested that years ago in an article.

By the way.... if you are going to make castings..... fix the weak spot!

The whole reason these things crack is a design flaw.  There is a dimple for the injection sight for the spru when they are made.  These gears ALWAYS crack at that dimple.

Soooo.......  if you are making castings, then body putty your dimple on the master so that your castings do not have the SAME flaw.

Ron,I'm already doing that.May make them available if they're not too horrible to cast.Best idea would probably be to use my gears as the replacements for the idlers,and the idlers as the axle gears.Unless,of course,my gears are tougher.Metal filled resin may be the ticket,the stock gears are really weak..

[mmagliaro]

Ron,
Are you saying that because the idler shaft is a little smaller in diameter, a glued/repaired axle gear will actually
hold together on it and not pop open again?    I don't know if I'd ever trust ACC to not just crack off
that slippery gear after a while.  Perhaps heat-melting over the crack with the point of a soldering iron after
 you glue it? 

This is interesting.  Identical gears, but two different axle bores.  Ewwww.

[LV LOU]

Ron,
Are you saying that because the idler shaft is a little smaller in diameter, a glued/repaired axle gear will actually
hold together on it and not pop open again?    I don't know if I'd ever trust ACC to not just crack off
that slippery gear after a while.  Perhaps heat-melting over the crack with the point of a soldering iron after
 you glue it? 

This is interesting.  Identical gears, but two different axle bores.  Ewwww.

You know Max,just sealing it with an iron may be the way to go.A good,temp controlled iron with a tiny tip and a little added plastic would be the way to go.
  Yep,it's actually the .005 interference fit on the driven axle that causes the huge split.It closes up quit a bit when you pull the axle.

[BCR751]

Lou,

If you do manage to create good castings of these gears, I would definitely be in for some.  I have two S2's that I tried the fix on but they still don't run very well.  Please keep me in mind.

Doug

[u18b]

Ron,
Are you saying that because the idler shaft is a little smaller in diameter, a glued/repaired axle gear will actually
hold together on it and not pop open again?    I don't know if I'd ever trust ACC to not just crack off
that slippery gear after a while.  Perhaps heat-melting over the crack with the point of a soldering iron after
 you glue it? 

This is interesting.  Identical gears, but two different axle bores.  Ewwww.

Max,

I never measured the axles..... I just observed:
Gears appear to be identical.
Idler gears spin
Axle gears are tight.

So yes, the shaft must be smaller.

My reasoning at the time was:
1.  You can't get replacement parts.
2.  This is not the BEST solution, but it is at least an improvement.

Of course, now with so many dead S-2, you can find a source for stealing them to acquire undamaged gears.

So, the gluing method is still going to leave the teeth wrongly spaced by a few microns, but my experience was that on a free spinning shaft, the glue held.

[drgw0579]

Even though the Atlas S2 will be arriving soon, I plan to keep my Arnold S2s on the roster for the foreseeable future.  I am looking for a junker for a source of parts, if anyone has one they want to sell for $10-$15, send me a private message.  Must have the electrical contacts intact. 

It's amazing that there's ebay sellers who still want $60 or more for these.

Bill Kepner

[LV LOU]

Max,the idler shafts are .0345,the axles are .038..I used a .037 drillbit to ream the idler gear out,it works great...

[peteski]

Max,the idler shafts are .0345,the axles are .038..I used a .037 drillbit to ream the idler gear out,it works great...

That is unusual.  This is a German-made model.  From my experience, European models are made using metric measurements. Shafts are usually 0.5, 1.0 or 1.5mm diameter.

But the ones you measured in this model are real oddballs: 0.88 and 0.95mm.  Those are really oddball metric sizes. Weird. I'm not doubting your measurements, I just find those shaft sizes odd.

[LV LOU]

That is unusual.  This is a German-made model.  From my experience, European models are made using metric measurements. Shafts are usually 0.5, 1.0 or 1.5mm diameter.

But the ones you measured in this model are real oddballs: 0.88 and 0.95mm.  Those are really oddball metric sizes. Weird. I'm not doubting your measurements, I just find those shaft sizes odd.

At least one has to be an oddball size,since one shaft is only a few thousandths smaller than the other.