BLI PRR-P5A In Now

[bbussey]

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!  

That’s great news!  How about a pic at least before we deluge you with fulfillment requests? 

[bbussey]

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.

Also, unless they’ve deviated extensively from the exploded diagram, the bushings are separate parts. Swapping the rear driver wheels onto the center axle components as you state should solve the issue without ill effect.

[peteski]

Also, unless they’ve deviated extensively from the exploded diagram, the bushings are separate parts. Swapping the rear driver wheels onto the center axle components as you state should solve the issue without ill effect.

I revisited the photos you posted and have some questions.  Are the center-driver bushings part of the wheel assembly, or are they free floating washers (installed between the wheelback and the bearing)?

You mention free-wheeling on the outer drivers.  I'm confused.  Are you saying that when the outer drivers shift all the way to the left or right side, they disengage from the idler gear driving them and start free-wheeling?  The gear on the outer drivers seems too wide to allow it to disengage from the idler gear.

Is the offset of the gear on the middle axle required because the gear that meshes with it is a double gear that also meshes with the worm?

[bbussey]

BLI mentioned free-wheeling.  I think the driver assemblies consist of everything documented in the exploded diagram, other than the lack of notation on the center driver bushings.  I think all the parts are interchangeable, despite what I was told.  And if the diagram is wrong, and the bushings are integrated into the wheel ... it's still not a major problem as additional bushing would need to be added to the read driver wheel rather than the existing bushing being ground down.  It still should be possible to disassemble the driver parts and assemble a center driver with flanged wheels and the proper bushings.

[narrowminded]

BLI mentioned free-wheeling.  I think the driver assemblies consist of everything documented in the exploded diagram, other than the lack of notation on the center driver bushings.  I think all the parts are interchangeable, despite what I was told.  And if the diagram is wrong, and the bushings are integrated into the wheel ... it's still not a major problem as additional bushing would need to be added to the read driver wheel rather than the existing bushing being ground down.  It still should be possible to disassemble the driver parts and assemble a center driver with flanged wheels and the proper bushings.

I looked in there and all of the wheels are driven and all should be interchangeable.  The bearings aren't integral but are captured by the pressed on wheels.  I think that translates into them not being a separate part as they are a part of an assembly.  They are a separate part and it would require taking the wheel off the axle to replace them.  But it sounds like they won't have separate bearings.  I don't blame them for that as I doubt you could ever wear out the originals. 

[Cajonpassfan]

3.8oz.

Thanks.
Pretty hefty.
Should help with pickup (assuming all wheels have pressure on the rails, per previous discussion).

I have absolutely zero need for one of these odd electric ducks, but I always cheer on another BLI release, as they seem to be making an honest effort to make improvements with each new model or decoder design. The new P4 Mikes and Pacifics are terrific.  This one seems to be a step backwards...but maybe there are simple fixes (which should have been handled BEFORE the release, imho).
Otto K.

[bbussey]

I looked in there and all of the wheels are driven and all should be interchangeable.  The bearings aren't integral but are captured by the pressed on wheels.  I think that translates into them not being a separate part as they are a part of an assembly.  They are a separate part and it would require taking the wheel off the axle to replace them.  But it sounds like they won't have separate bearings.  I don't blame them for that as I doubt you could ever wear out the originals.

Guaranteed they will not have all the components of each driver assembly available separately.  What I meant was that they are separate components in the assembly, so it should take little effort to combine the necessary components from the rear driver assembly and center driver assembly to create a functioning center driver assembly with flanged wheels that conduct.

[narrowminded]

I am sure that any wheelset will fit any bearing slot, gears and all.  The flangeless wheel is accomplished by turning the flange off the wheel but also turning it undersized by about .010" and that's the biggest part of your objection to the wheel being visibly off the rail.  I don't have any major objection to that but my board doesn't have the rails right at eye level so it's not really noticeable.  If it were that high I'd probably object, too. 

I'm sure that is done in part to assure that the thing doesn't wind up sitting on that center wheel over uneven track, acting like a teeter-totter, lifting the traction tire up and stalling the train.  But that may not happen if you stick a flanged wheel in the center slot because I think the traction tire is slightly over the normal wheel diameter and, if so, would not cause trouble other than an extreme rail bump.  I might want to try that too but as I said, it's not a real big issue for me. 

Right now, with the pickup on both trucks fixed and a good wheel cleanup of some waxy substance on a few of the wheels, eight wheels at work plus one drive axle, I find pickup is no longer an issue.  The performance really is pretty flawless.  The wheel flange and obvious rail clearance when looking right at eye level?  That would be nice if that wasn't so.

BTW, I made a video with my phone of the loco running but am having trouble uploading it.  When I get that figured out I'll post it.  They updated something to make my life easier when I could always upload them before and now can't.  Did I mention how much I HATE some of this "technology"?

[peteski]

I'm sure that is done in part to assure that the thing doesn't wind up sitting on that center wheel over uneven track, acting like a teeter-totter, lifting the traction tire up and stalling the train.  But that may not happen if you stick a flanged wheel in the center slot because I think the traction tire is slightly over the normal wheel diameter and, if so, would not cause trouble other than an extreme rail bump.  I might want to try that too but as I said, it's not a real big issue for me. 

Teeter-totter?  That seems like a bit of an exaggeration to me.  There are multiple models of European (and probably Japanese) prototype locos with 3 or 4 large diameter drivers mounted in a stiff frame, and none of those feature flangeless drivers, and no drivers hover above the rail.

What we have here is an oddball design. It seems that more and more offshore model designers are trying to reinvent the wheel. Even Arnold GG-1 has two 3-sxle trucks with large diameter drivers mounted in a rigid frames.  All have flanges and none are hovering.

Many steam locos also have 3 or 4 large diameter drivers mounted in a stiff frame, and all the drivers are designed to stay in contact with the rails. No hovering.  I really think this was an attempt for some designer to deal with a non existing problem. Flexing their innovating muscle.

This loco could also have been designed with its TT driver in the center, so any possible teetering would be on the TT.

[nkalanaga]

The NWSL "Puller" shouldn't have any problem removing and replacing the wheels, if you don't have an arbor press.

[bbussey]

I have the NWSL tool.  I don't anticipate any problems constructing the new driver assembly.  The difficult part is getting BLI to send the parts.

[narrowminded]

This loco could also have been designed with its TT driver in the center, so any possible teetering would be on the TT.

The point was that it's not a source for a major pickup repair for this reason nor for a big traction improvement as not all of the wheels will be engaged at all times.  If there's a problem with either of those it won't be reliably fixed with a third axle in a rigid frame mounting.  It might help until the next minor anomaly in the track's surface but then you're right back where you started.

[narrowminded]

Here's the performance video link.  Now that I got that updated so I could upload I'll make another showing the fix.  I still have to make that.

[peteski]

The point was that it's not a source for a major pickup repair for this reason nor for a big traction improvement as not all of the wheels will be engaged at all times.  If there's a problem with either of those it won't be reliably fixed with a third axle in a rigid frame mounting.  It might help until the next minor anomaly in the track's surface but then you're right back where you started.

My point was that over the years there were many models produced with rigid frames and 3 or more drivers, with all the drivers contacting the track, and none of those models had any serious pickup or traction problems.

Something was bugging me, I had to re-index my memory cells, and I finally realized that BLI pulled this "flangeless hoveing driver" stunt before, on the PRR T1 locos.
See https://www.therailwire.net/forum/index.php?topic=50606

[narrowminded]

Got the pickup fix video done.  It shows (the best I could with the phone) what the problem is, the two parts to fix it, and installation.  Enjoy!  

NOTE: The video originally posted here was replaced with this updated, final version of the installation instruction utilizing unmodified factory springs.