Cracked frame

[nstars]

When we were checking some engines for an upcoming event we found out that one of our Intermountain F3 units did make some noise, but wouldn't move at all. Removing the shell was quite a challenge as closer inspection showed that one of the frame halves had major cracks. It looks like the frame had zinc rot. Has anybody seen this before with an Intermountain engine?

Marc

[nkalanaga]

Into the early 70s it wasn't uncommon, but no, I've never had it happen to a loco of any brand.

[JSL]

I haven't seen that in an Intermountain loco, and I've put lots of decoders in there F units.

[alhoop]

I had a Central of Georgia F unit, one of IM's first,  to swell (see arrows) so that it wouldn't run and I had a hard time
getting the shell off. Not shown but from the top the frames were bent to the left almost like it had Peyronie's disease.
IM replaced it - no problems.


Al

[carlso]

that would not surprise me since you said an IM F-3.

Carl

[djconway]

Of the 12 I'm F`s I have, I discovered a F3 with a cracked frame.  A phone call to IM and a few $$s later and I was back in business.

[peteski]

That is weird to see this type of problem in the 21st Century. But then again, these things are made in a country where cutting corners and minimizing cost is the top priority.

[nstars]

That is weird to see this type of problem in the 21st Century. But then again, these things are made in a country where cutting corners and minimizing cost is the top priority.

I agree, but if you see the frame, than it's quite astonishing.

Marc

[loyalton]

Remember, it's still a casting, an ancient, imperfect process. An N loco frame is not going to be magnafluxed or otherwise pre-tested because its strength is not critical nor does anyone (read: most Americans) want to pay more for the process. It's cheap enough just to replace the few defective ones that pass through the building process. Peteski, Chinese manufacturing responds to its biggest customer, the US, which generally means making the cheapest product. All those Wal-Marts and Harbor Freights exist for a reason. And on the contrary, Atlas, for one, is made in China and I don't see any overall quality problems there.

I hear people moaning about US industry no longer able to recreate the one-piece cast frames used for big steam locomotives -- "lost technological ability". Well, who would want something like that nowadays with its high weight and limited flexibility? A cracked frame was not uncommon and they're still finding frame defects when steam locos are being restored. Modern welding fixes that. Now restoration generally means using original parts. But for practical purposes in operating steam locos today, it would be better, for example, to change to modern alloys for steam pipes and to replace friction bearings with roller bearings. So in N, I look forward to something better than the current split cast frames. But whatever it is, it will cost more than a split frame.

[peteski]

Remember, it's still a casting, an ancient, imperfect process. An N loco frame is not going to be magnafluxed or otherwise pre-tested because its strength is not critical nor does anyone (read: most Americans) want to pay more for the process. It's cheap enough just to replace the few defective ones that pass through the building process. Peteski, Chinese manufacturing responds to its biggest customer, the US, which generally means making the cheapest product. All those Wal-Marts and Harbor Freights exist for a reason. And on the contrary, Atlas, for one, is made in China and I don't see any overall quality problems there.

I hear people moaning about US industry no longer able to recreate the one-piece cast frames used for big steam locomotives -- "lost technological ability". Well, who would want something like that nowadays with its high weight and limited flexibility? A cracked frame was not uncommon and they're still finding frame defects when steam locos are being restored. Modern welding fixes that. Now restoration generally means using original parts. But for practical purposes in operating steam locos today, it would be better, for example, to change to modern alloys for steam pipes and to replace friction bearings with roller bearings. So in N, I look forward to something better than the current split cast frames. But whatever it is, it will cost more than a split frame.

Um, couple of comments:

1. I don't know if you would call what they do "casting"  The molten metal is injection molded under pressure into a multi-piece mold (just like it is done in plastic injection-molding).  You can often see traces the gate where the metal was injected.

2.  Whatever you want to replace the split-frame in the N scale models would have to be as heavy or heavier than the current metal alloy being used. Maximizing weight is very important for N scale locomotives.   Last thing you want in your N scale locomotive is a lot of open space.

3. As far as who is to blame for poor quality products,  it is the consumer like you or me.  We aren't willing to pay top dollar for quality.  Plus I'm sure that the factory management does all they can to save a Yuan.

[victor miranda]

from all I have ever read, the plastic injections get called castings too.
Along with all metal moldings are called castings.

one of the things I am told makes Japanese motor bikes so great was
all the care put into the metallurgy of the castings.
There is a lot of discussion about trace elements and their effects.
In a LOT of metals trace amounts of lead make very little difference
this is not true with Zamac and its sort.
Zinc Pest is caused by trace lead levels.
the metals/alloy Biz sometimes forgets this and sweeps up other metals
headed to the Zamac process,  as an off hand guess I bet the contamination
got into the zamac from the Copper.

I suspect our toys would be done with Tin if it were less expensive.

... I also think he was trying to state he wants a different
design from vertical split frame. (something better...)

victor

[nscaler711]

As for this "not" happening with Atlas, some one on Trainboard has a Atlas SD35 that has zinc pest/rot whatever, and the frame halves are stamped ©2000 Atlas, his was so bad that it shattered the shell and walkway... So theres that.
I'd sure like to see Kato having these problems though... 

[djconway]

Well last night while trying to figure out why another of my F3's was slowing and binding going into curves.  I found another rotted frame, this makes 2 out of  12 with this problem.  IM this is'nt good.  N-Scale this is'nt good, with the buy it now or you may never see it again philosophy you have to buy it when you see it. Makes me wonder if I will buy any of the next release.

Has IM addressed the issue for the new release?

[peteski]

Has IM addressed the issue for the new release?

Is this really such a  wide-spread problem, and is IM even aware that it is?

[nstars]

It looks like I'm getting a new frame for my F3. The other F's are looking good (sofar)

Marc