BLI PRR-P5A In Now

[narrowminded]

I received my P5a yesterday.  It's beautiful!   Sound is good, weight is good, with the traction tires the pull is excellent, detail is nice, and it has the same damn pickup issue that all of you have been complaining about.   I think I have a fix figured but as others have said, it's pretty inexcusable to be fixing a new, expensive piece like this.  Especially when the fix will probably be something that would have cost $ZERO$ in production for a matter of recognizing that pickup with that wheel arrangement would require the truck pickups to be effective.  As it is, there's virtually zero weight on them and even though they are hard wired and have a light spring pressing them down, the arm that locates the trucks just flexes up, doesn't even compress the very light spring that's supposed to apply weight to the trucks.  The best that rig can hope for is to keep the trucks from derailing at will.  As a result there's frequent dropouts and  stalls at any speed step below about 30.  And even though there are three larger wheels, the center set doesn't engage the track, the one end is insulated by the traction tires, so that leaves one axle to pickup the power...  unless the trucks at each end worked reliably.  Then it would probably be a pretty decent runner.  It's got everything else for me!  So I guess we can wait and see if BLI comes up with a retrofit part or just start to fix it myself.

[bbussey]

I'm glad yours is running reasonably well.

I just noticed on the exploded parts diagram, the decoder appears to have the six keep-alive capacitors.  In the drawing, it looks exactly like the board in the Mikado photo above.  So maybe all the problems will be solved by increasing the conductivity.

I've been going back and forth with BLI the past two days trying to pry two rear wheelsets out of them.  They claim spare parts are still a few days away.  I'm going to stay on them daily until I get the parts.

[bbussey]

I took part of my lunch break to review the unit. Definitely traction tires on the front grooved wheels. I removed the pilot trucks and stretched the steel springs so their at-rest state is twice as long as they were. I also tightened the screws on the pilot truck pivot arms to just before they are immobilized, so that there is no up/down movement at the screw. Those adjustments increased the pilot truck downward pressure significantly. I was able to get the unit to perform at notch 5 on the throttle. It originally was notch 30 out of the box.

It still needs at least the center driver conducting, and I’ll sacrifice pulling power for conductivity and swap out the lead driver also.  Here’s a test run after the pilot truck adjustments. Much much better, but still not good enough.

[nstars]

I received my P5a yesterday.  It's beautiful!   Sound is good, weight is good, with the traction tires the pull is excellent, detail is nice, and it has the same damn pickup issue that all of you have been complaining about.   I think I have a fix figured but as others have said, it's pretty inexcusable to be fixing a new, expensive piece like this.  Especially when the fix will probably be something that would have cost $ZERO$ in production for a matter of recognizing that pickup with that wheel arrangement would require the truck pickups to be effective.  As it is, there's virtually zero weight on them and even though they are hard wired and have a light spring pressing them down, the arm that locates the trucks just flexes up, doesn't even compress the very light spring that's supposed to apply weight to the trucks.  The best that rig can hope for is to keep the trucks from derailing at will.  As a result there's frequent dropouts and  stalls at any speed step below about 30.  And even though there are three larger wheels, the center set doesn't engage the track, the one end is insulated by the traction tires, so that leaves one axle to pickup the power...  unless the trucks at each end worked reliably.  Then it would probably be a pretty decent runner.  It's got everything else for me!  So I guess we can wait and see if BLI comes up with a retrofit part or just start to fix it myself.

I think your approach is the best. Given the length of the loco and the short wheelbase of the drivers, the last thing you want is load on the center driver as this could result in loco which runs like a duck over the track. I haven’t seen a P5 in reality yet, but better pickup from the trucks should be essential and this requires does indeed require weight. BTW also make sure the blackening is removed from the wheels including from the truck. This is a common issue of BLI. You should have seen my P3 Mikado on its first run, that was terrible, now she runs great.

Marc

[Mike C]

Is there a way to shim the middle driver down with some conductive material?

[Cajonpassfan]

Out of idle curiosity, how much does this loco weigh?
Thanks, Otto K.

[greenwizard88]

Out of idle curiosity, how much does this loco weigh?
Thanks, Otto K.

3.8oz.

[bbussey]

Is there a way to shim the middle driver down with some conductive material?

I don’t understand the question. The tire on the center wheel is thinner, meaning the diameter of the wheel is smaller. Replacing the middle driver with a second rear driver is the only solution. I’ll take my chances with the three conducting wheelsets with fixed bearings on the rails (unlike floating wheelsets on Kato designs) and trust my track work is solid enough not to worry about wheels lifting. The four driver axles on the Mikado are fixed and that model runs fine. I don’t think it will be an issue.

[Point353]

It still needs at least the center driver conducting, and I’ll sacrifice pulling power for conductivity and swap out the lead driver also.

The solution to the pulling power problem is to run them triple-headed.

[peteski]

The solution to the pulling power problem is to run them triple-headed.

Hard-wiring 3 locos would also solve the electric pickup problem. 

[Cajonpassfan]

Ouch, that's an EXPENSIVE solution...
Otto K.

[bbussey]

I've been corresponding with BLI over the past few days.  They want me to send the engine in, I want them to send two rear gearsets.  We'll see how the negotiations go when they resume (I assume) on Monday.

The latest — they've reached the same conclusion (or most of it) regarding the pilot trucks.  They say to tighten the anchor screws of the pivot arms.  I told them the springs need to be stretched as well.

Regarding the drivers, the blind wheels have an extra bushing that they say keeps the gear in register.  They claim the rear driver wheel will not work.  I countered with the statement that bushing can be added if necessary to make the mounting of the rear driver match that of the blind driver.  I responded to their last email after business hours so that's why I suspect no further correspondence until Monday.  See the attached photos they supplied.

[nkalanaga]

Way off-topic, but looking at that picture, what was the standard wire height for the PRR?  It looks a lot higher than most models will reach.

MILW and GN used 24' 2", but I've always heard that the PRR was lower.

As for the model, they have three driving axles, the wheelsets for all three are different, and they're not interchangeable?  That sounds like very bad design, from an economic standpoint, for them, and almost certainly unprototypical.  I doubt the PRR would have done that!  With no rods, there's no reason all three couldn't have been identical, except for the traction tire wheels themselves.

[narrowminded]

I don't know what you guys are complaining about.  Mine's running great!  For the last hour or so I just let it run around the layout at speed step one.    Made two whole laps!  That's seven #5 Atlas turnouts per lap!

Yeah, I got a fix.  I'll send the parts to anyone who has one and needs them.  They're a total drop in piece.  Take out the one truck swing screw at each end, lift the truck out, drop the 3D printed piece into the cavity, reinstall the truck.  Done!   I'm still going to test a few more, moving the preload dimensions about .005" at a time but it allows the springs to preload the truck and compensate for irregularities as was the original intention, I'm sure.  That was before the flimsy plastic arm was made and it wasn't stiff enough to let the spring work.  The arm flexed the full travel distance available before the truck spring ever had a chance to load anything.  This piece fixes that so the spring can now do its thing as it was always supposed to.

I'm quitting now and it may be a few days depending on my duties.  Now that I know I'm onto it I'm going to make a couple more, moving .005" at a time, just to be sure it's optimized.  It'll be worth the effort to be sure it's the best it can be.  I really like this thing now!!!   

And BLI has a problem.   This might just be the simple fix that I'm sure they'll be looking for.  I'm sure it's every one of these.   

[peteski]

Regarding the drivers, the blind wheels have an extra bushing that they say keeps the gear in register.  They claim the rear driver wheel will not work.  I countered with the statement that bushing can be added if necessary to make the mounting of the rear driver match that of the blind driver.  I responded to their last email after hours so that's why I suspect no further correspondence until Monday.  See the attached photos they supplied.

Another solution would be to get a flanged driver then push the wheels off both axles, and press the flanged wheels onto the middle drive axle.  No quartering is needed.  Of course owning a mini arbor press makes this type of task easy.