Best Of Notes on body-mount couplers (work-in-progress)

[GaryHinshaw]

A follow-up message from Will:


Thanks, N Scalers,
     I'm just trying to get an idea of how many Tess should assemble and that Bowser should send to me.  I will get back to you with payment particulars, etc. when they become ready!  Thanks, again!
Faithfully,
Will
 
PS:  Be sure to tell others that are interested to contact me and send me their E-mail addresses.

[wazzou]

Maybe I've missed it but what would 5-10 pair units run $$$ wise?

[GaryHinshaw]

Maybe I've missed it but what would 5-10 pair units run $$$ wise?

The cost per pair will be approx. $3.50.  Depends on how we package them for you.  We'll do it as cheaply as possible!

Not cheap, but cheaper than before.

[daniel_leavitt2000]

I'm on board for twenty sets to start. If all works well I'll get another 50 in the next six months.

[pfs]

I got back to Will with my number as well.

[GaryHinshaw]

Progress on the Full Throttle "naked Talgo" front.  Will has received the initial shipment from Bowser and is ready to take definite orders from folks.  He should have already sent email to those who responded earlier, but in case you didn't and are still interested, you can probably still get some.  Here is the note he sent out:

Dear N Scale Modelers,
     Please excuse the generic nature of this E-mail, as I'm trying to reach all of you that have shown interest in these Z Scale Naked Talgos.  Well, finally, I have received my first shipment of this beast!  Ha, ha!  What is not funny is that Bowser sent me 500 pieces instead of 500 pair!  However, I contacted Lee immediately and he is putting Tess right on it!  Hence, I should have the remainder next week, and I can finally take your orders and payments.  Yes, let's firm this up!
     Please get back to me with a confirmation of your initial orders, and I will make up an invoice for you, which I will send Eposte-Haste!  I will then expect payment.  Of course, PayPal is easiest for me, but you may also send a personal check if you wish.
 
     When using PayPal, send payment to:  dewaa128@aol.com
 
     When sending a check, make it out to William Dean Wright and send to:
[omitted by gfh - contact him by email at the address above for the postal address]
 
     I'm sorry it has taken this long to get back to you all, but such is the nature of "special orders."  Now that the Holiday Season has past us, it should be easier and quicker to make this sort of thing happen.  I hope!  Nonetheless, It is time for me to take your actual orders and get to sending out these wheel-less talgos with the long trip pins.  I'm ready if you are!  Thanks for your patience and understanding, and I really hope these work out for you!  Keep me informed!
Faithfully,
Will

I encourage you to give these a try.

-Gary

[daniel_leavitt2000]

Just an update, my 20 sets are on the way.

[Guilford Guy]

My 12 sets arrived today, so hopefully I can get those installed this weekend.

[bbussey]

... Changing the wheelbase is straightforward: remove the underframe weight and cut the bolsters off just inside the truck pad and glue them to the floor in line with the last post in the centerbeam (and the little tow loops)...

Gary,

I understand that the wheelbase was incorrect for the model.  But aren't those the bolster ends sticking out on the sides?  Don't they have to be moved outward (or removed and reconstructed) as well?

[GaryHinshaw]

Gary,

I understand that the wheelbase was incorrect for the model.  But aren't those the bolster ends sticking out on the sides?  Don't they have to be moved outward (or removed and reconstructed) as well?

Absolutely!  Good eye Bryan.  This is a good example of my Do No Harm policy: since I doubted I could shave those off neatly enough - in a finite amount of time - nor add new ones under the ratchet that looked good, I punted.  Same with the end ribbing on the bulkhead and the framing along the top of the centerbeam, neither of which are correct for this car.  The wheelbase error, the ride height, and squaring off the bulkhead top were easier to fix without leaving visible scars.  And they really enhance the overall silhouette of the model.

Cheers,
Gary

[ednadolski]

Hi Everyone, I just thought I'd take a crack at what a photo-etched brass coupler pocket for an N-scale body-mounted coupler might look like, and I'd like to ask for your thoughts and feedback.   Here is a crude sketch:



I haven't settled on any specific dimensions, or even which couplers this might support:  Accumate, McHenry, and/or Full Throttle.   The FTs might be the closest to scale size.  I wanted to keep it simple, so this is not much more than a slightly refined version of the good old 3/32" x 3/16" rectangular brass bar, with dimensions to be optimized for a specific coupler, plus a few cosmetic details.

Anyways my thought is that the black areas represent 0.010" half-hard brass, the red is a half-etch, and the white areas are fully etched through.  Assembling the coupler pocket starts by forming the two sides of the main body into a C-Channel shape.  The bottom and top pieces are then attached, perhaps using CA or perhaps soldered if extra strength is needed.  The front screw is used to hold the coupler in the pocket, and the rear screw holds the pocket to the carbody.   The pocket could also be epoxied to car body in cases where a screw might not be practical (e.g. a tank car or hopper).

There are a few other notes:  there is a small hole in the bottom cover to allow for attaching the end of a cut lever.   Also, the two tabs on the side of the bottom cover are meant to be folded up, so that a BLMA air hose can be CA'd into place.

Thanks for looking, please let me know your thoughts.

Best,
Ed

[Philip H]

Ed,
I'll take a dozen to start, and I'd like to set up a regular purchase/shipping arrangement.

Oh wait, you need to etch it first.  Drat.

I'd say do three sizes - one for FT, one for MTL, and one that would fit everyone else.  That way I can get all my fleet converted with the couplers I have.

[GaryHinshaw]

Thank you for rebooting this topic Ed!  Your design is very close to what I have been thinking of; but I have failed to draw mine because of the learning curve required on the free CAD package I have...  Now you've prompted me to sketch it out in Power Point to keep the ball rolling.

Here is my sketch in the same color scheme as yours (plus blue, which is a half-etch on the back); also with no dimensions, just concepts:



The similarities:
* .010 etched brass
* fold-up sides
* bottom cover with screw hole and fixtures for cut lever & air hose
* multiple screw holes.

The differences:
* no top plate  (I'm not sure what function yours serves...?)
* half-etch fold-up lip
* tab & slot fixture for the bottom cover to provide longitudinal stability
* a top plate that extends further back than the sides to allow for mounting flexibility (including extended draft gear).  The red circles are half-etched dimples with the idea being that you would drill out the hole that best matched your car's mount point.  (There are probably way too many half-etch dimples and more cover material than needed, but this is just a sketch.)

A few other notes:
* The big hole in the bottom cover is 00-90 clearance size.  The white hole on top is a 00-90 tap size.  The idea is this: if the main mount point is this position, you would ream the hole to clearance size and simply screw a long 00-90 all the way through to hold the (FT) coupler and mount the box.  If this is not a suitable mount point (e.g. extended draft gear) you would tap 00-90 threads and use a short screw to hold the coupler and cover, then drill another clearance hole at the best-located red hole and mount the box.  Any extra top-cover material behind the mount point can be trimmed to suit.

Comments?  Let's get a test run going soon!

Thanks,
Gary

P.S. What is the function of the slots in your side panels?

[ednadolski]

Hi Gary, I like what you've put together!    Let's bat this about a bit more and see if we can come up with a drawing to send out to an etching house.

I've updated my sketch to incorporate your ideas  (again, please pardon the crudeness):



I’m still lacking dimensions, so we'll need to hash these out.   I'm traveling at the moment so it'll be a few days before I can get back and take some measurements.  One key question:  which coupler would be good to target for a first cut?   It’ probably a choice between the FT or the McHenry,  and it seems like the FT would be the one to pencil in, considering that it is closer to scale and seems to work well,  but I also have concerns about the availability.  I've got a few on order to try out but I was wondering -- do you think Will could maybe get just the bare coupler, without any truck?    What would we need in terms of quantity to make that happen?

One dimension that is affected by the coupler choice is the overall width.  This is an important one, since the width is what limits the truck swing and therefore the curve radius that a car could negotiate.  I don't think axle clearance is too much of a concern, since the overall vertical height ought to be less than any plastic coupler pocket.   The other thing to consider is the size and location of the coupler screw hole.   It should be sized such that no bushing is needed, and it should be located so as not to overtly restrict coupler swing, yet also not let the coupler stick out too far.   If we get the vertical size right, then I'm not too concerned about the coupler drooping or sticking up too far.

One thought that I had that doesn't show up on the sketch: it might be better to go with 0.015" brass stock over 0.010, as that would make the half-etch areas a bit more sturdy.    Also, I've drawn the pilot holes for the 00-90 body mount screws somewhat smaller, with the idea that they could be located closer together and thus a little easier to customize to the specific car.  However I'm wondering, how hard is it to hand-drill thru brass?    If it's tricky to do with small bits, then maybe we'll want to etch just a few 00-90 tap-sized holes in key places.

Cosmetically, one idea I've worked into the sketch is that the half-etch sides of the bottom cover will project past the vertical sides of the pocket, in order to get that sort of 'beam/flange' look that the prototype has:  http://www.mellowmike.com/Prototypes/2bay_axle.jpg.   Similarly, the thought behind the 'slots' was to emulate the look of the key/slot on the prototype (as in the .jpg).

Thoughts?

Ed

[ednadolski]

FT internal coupler pocket dimensions

W: 0.132 in.
L: 0.184 in.
H: 0.034 in.
« Last Edit: August 03, 2010, 09:22:38 PM by David K. Smith »

Aha, I found these dimensions from David in another thread.    So for the FT coupler we should use these as the inside dimensions of the pocket.

Ed