brass Key Pennsy Q2 questions- solutions from Pennsy fans?

[u18b]

Here's to hoping someone here has a Q2 and can give me some help.

I'm working on a Pennsy Q2 class 4-4-6-4 for someone.

Wow, this is a stunningly gorgeous locomotive.   But this is looking like the stereo-typical shelf queen brass loco that looks drop-dead beautiful but just does not really run.

So I'm looking for help to hopefully get it to run well.

Now, Mark Spookshow's experience is REALLY confusing.
http://www.spookshow.net/loco/key4464.html

His ran on 15" curves almost flawlessly.

That has not been my experience at all.  I know mileage may vary- but yikes!   
Mine BARELY runs on 19" curves (Unitrack) and prefers the giant 28" Kato curves.

I asked Mark about it and he said this is one loco that he didn't buy.  Someone sent one to him to test for the encyclopedia.
Thus a part of me wonders if Mark's had already been modified.

Here are the problems I'm facing. 

1.  The tender trucks on that really long were too confined and caused derailments.  I determined the fancy delicate piping along the bottom edge of the tender wall was restricting the pivot of the trucks.  I gently bent the piping outward and that problem has now been corrected.  However, the problem can return since when you pick up the tender your fingers can pinch those pipes back inward.  Care is required in handling.




2.  The front wheel on the front pilot truck appears to short on the bottom of the air pump (paint is missing from the bottom air pump rivets- a common sign of shorting).   Looks like filing the bottom of the air pump is called for to give more clearance.



3.  The pony truck has all kinds of problems.  The first is shorting on the drawbar.   There is almost zero clearance between the center back brace of the pony truck and the drawbar screw- thus a short.   




Looks like I need to file the rivets off the top of the brace on the truck on order to give more clearance.  Pony truck rivet tops are missing paint indicating the rubbing and shorting.



4.  The pony truck also appears to practically drag on the rails.  The clearance over a turnout frog is practically zero.  The solution would seem to be to raise the pony truck frame a bit.

5.  But raising the truck frame a bit appears impossible.  There is piping detail along the bottom edge of the firebox on the boiler as you can see in this shot.   This piping interferes with the leading (left) top edge of the pony truck!  In fact, the pony truck appears to be designed to sit in-between that piping thus restricting the truck's pivot (potential derailment cause).   So how does the loco even run on curves then?   Because the wheels appear to be really loose.   It appears Key designed the pony truck to be slightly oversized and the wheels float and can thus make some big curves.



What I'm wondering is if anyone here on this board has also seen these problems and corrected them.

Anyone have a Q2?   
Run reliably?
What track do you run it on?

Here is a reason why I'm thinking someone made mods to the sample Mark used.  In the following Spookshow photo, there is white styrene on the back left side where the insulated drawbar screw goes.   That white styrene does not appear to be stock.    So I think his was modded.

Any help?

(John Sing  @atsf_arizona    .... was that your Q2 that you sent to Mark?)

[u18b]

I posted the photos in the text above.

[garethashenden]

Can you tighten the drawbar screw any further?

[u18b]

Can you tighten the drawbar screw any further?

No.   It's properly snug.

The screw did have some typical burrs from the screwdriver slipping out of the slot.  While only angstroms, these burrs did stick out a bit.   I gently filed the screw head smooth.

[atsf_arizona]

Hi, Ron,

I am the one of several,  that helped Mark and Spookshow with his review of the Key Pennsy Q2 4-4-6-4 brass duplex review.  ( http://www.spookshow.net/loco/key4464.html  )

I don't have this loco anymore (I bought my copy at N Scale Convention 2008 auction, then sold it back in 2010 for a nice price, but sure wish I'd held onto it now!)

Here's the Web-Archive version of website I did on my copy: https://web.archive.org/web/20151002184832/http://home.comcast.net/%7Eatsf_arizona/v20_Key_N_scale_PRR_Q-2_Duplex_4-4-6-4_6131.html ,
look at it and download what you want if you can reach it.  Note that if there's too many hits to this URL, the WayBack Machine Web Archive will probably cut off access to limit their daily bandwidth.
I have low-res copies of the photos I took, you can reach out to me and I'm happy to share them with you, if it helps.

That said, I do remember testing this loco extensively prior to selling it.  Bottom line, it ran really well, except for some intermittent electrical pickup "pausing" when trying to run on N Trak layout.

Feel free to ping me if you want to discuss further, here's some thoughts/experiences:

• My particular N scale Key Q2 brass model ran very nicely and smoothly on my dining room table Kato Unitrack test loop, on anything down to 15" Kato Unitrack curves. 
• On curves sharper than that, the drivers would bind on the curve
• I did not experience any of the electrical shorting problems that you describe, on my loco.  As far as I could tell, my loco was stock and un-modified.
• I remember that the electrical pickup was a bit finicky, i.e.  if the track was perfectly smooth i.e. the dining room table Unitrack test loop, the stock drawbar electrical arrangement worked well and the beautiful loco ran smoothly
• But on "bumpy" NTrak convention layouts, it definitely would stutter at times due to the track not being perfectly level  (that was the reason I sold the loco... sure wish I'd kept it now!)
• I remember talking with Hans and Marc Starmans at that 2008 N Scale convention where I bought the loco, and they told me their Key Q2 had the same issues.  Hans ended up doing some of his magic worksmanship to rewire the electrical pickup on his Q2.   If you reach out to the Starman's, I'm sure they would be happy to share, I'm sure they know everything there is to know about this loco.

Bottom line:  my copy of this loco ran smoothly and well.  It just required bigger curves than my 4x4 layout had, and at the time I wasn't collecting N scale "Pennsy odd-ball motive power" like I am now.....


Great to see this thread, Ron, and looking forward to seeing what your version of magic on this magnificent, beautiful Key Q2 Pennsy Duplex 4-4-6-4, will look like here.   Certainly, the beauty of this model is stunning, and if you can get it to run well, that will complete the picture wonderfully for your client who gave you the loco to fix.   Let me know if you end up collaborating with Hans Starmans on this one - he seemed to know a whole lot about this loco, I recall.

Ron, I still remember fondly our National Train Show visit and post-show dinner from Saturday at NMRA Orlando 2017 with you and your son and me.  It was one of the memorable days of my life.  Hope to see you again sometime!

All the best for 2025 and beyond!

[wm3798]

I did a decoder install on one a long time ago, I believe it was for Eric White, who was building a "what if" transcontinental PRR layout at the time.



From the date on the picture, I did it after I took down my layout, so I only ever ran it back and forth on a test track.
Maybe you can check in with him about his experiences running it.  @eric220

Lee

[u18b]

Yes  John.  I fondly remember that visit too.  It was a great trip.
I hope some day to be able to meet more guys on this board.

[u18b]

Well, I have made some progress.

I concluded the frame was bent.
Right behind the rear driver (essentially the motor area.).
The frame being compressed in the area under the cab allowed the shell to sit too low on the rear pony truck.

Here is the one I'm working on. (before photo).

Notice that pipe obstructs the edge of the truck.



Now look at Lee's photo.  Red arrow.
The pony truck appears to be clearing that pipe and riding under it,  ie- the pipe is riding higher.



So Straightening the frame has solved the derailing problem from the pony truck.

But I'm still having problems with the pilot wheel shorting on the frame (blue arrow).

I'm currently working on a solution.  I've added a leaf spring to the frame behind the coupler to press down the pilot truck.
I made improvement in running, but I think it still needs tweaking.

At least I see that it can now run on 19" curves (which is also equal to a Kato #6 turnout).   So that is progress.    I still have my doubts this one will run on 15" curves.   But the customer is designing a layout with wide curves so he can run locos like this.    He sent this to me to install sound.   But I have to correct all these problems first.

[wm3798]

Good thing I posted one of my rare photos where all the wheels are on the track!

Lee

[eric220]

I've got two of these beasties.  The one that Lee decoderized for me runs basically flawlessly.  I had 15" minimums, and it could do laps with no problem.  My other one has some gremlins, but I bought it late in the life of my basement monster, so I haven't had much of a chance to mess with it.  Something to remember is that Key made several variations of the Q2.  6131 is labeled "as built," while 6175 doesn't have subtext.  I've got the models right here next to me, so if any other photos would be useful, feel free to ask.

The photo in my signature is from the trip when I brought my T1 and Q2 out to Colorado do visit Dr. Hotballz, and we figured out that they won't do the curves on the JD.

[wm3798]

But they sure look good in still pictures!

[eric220]

True 'dat!