Adventures in prototypical True-Scale coupler pockets.

[tom mann]

Aren't you supposed to wear black socks with sandals like that?

[C855B]

Aren't you supposed to wear black socks with sandals like that?

Dad sandals? Eww!

[sirenwerks]

What's wrong with the German tourist look?

[Lemosteam]

So I think the next revision is ready to print.  I went and placed it into my NP flat car file to see what it looks like.




Hopefully this will be the final version and I can start making different conversions for various cars.

Jason

I am thinking of doing some similar designs and some I already have that experienced serious warpage.  Would you mind sharing a before and after Bestine picture of this design?

[wcfn100]

I am thinking of doing some similar designs and some I already have that experienced serious warpage.  Would you mind sharing a before and after Bestine picture of this design?

Interesting you should mention that.  I've been wondering the last couple days if I should make a channel for a weight that could also be glued in to help with any potential warping.  I'll have to look at the drawing and see if some sort of metal stock would fit.


Jason

[wazzou]

Interesting you should mention that.  I've been wondering the last couple days if I should make a channel for a weight that could also be glued in to help with any potential warping.  I'll have to look at the drawing and see if some sort of metal stock would fit.


Jason

I have seen others using Shapeways to design a printed metal weight to be used in conjunction with the FUD/FXD.
In this case, the fish belly component could be designed in metal to be snapped into place?

[C855B]

I have seen others using Shapeways to design a printed metal weight to be used in conjunction with the FUD/FXD.
In this case, the fish belly component could be designed in metal to be snapped into place?

Or, in this case, loco chassis extenders: http://www.shapeways.com/product/W5G3GLDWD/alco-c-855-n-scale-chassis-extenders-x2?optionId=59290061

They worked pretty well. Expensive, tho'.

[Lemosteam]

Interesting you should mention that.  I've been wondering the last couple days if I should make a channel for a weight that could also be glued in to help with any potential warping.  I'll have to look at the drawing and see if some sort of metal stock would fit.


Jason

Warp is easy, I had thought of solid square brass rod that would be shove into the length down the sides and down the middle.  Twist on the other hand, without making a full rectangle, soldered or folded on the corners, well...

Or if it snapped into a metal deck.

I'm just nervous about a few things WRT to this phenomena. I once printed a fairly long U channel, with high flanges on the sides about 6X the thickness of the floor and it was warped to heck and bowed across the floor and twisted.  Needless to say that idea was scrapped quickly.  then @chicken45 's PRR F22 flats well, I have stayed away from those sorts of designs till I can solve the structural issues that plague the prints.  Some folks are framing their parts with open wire boxes, but I don't know what benefits were observed.

Then there is the length calibration issue I have been dealing with.

I might take some pics of those designs tonight...

[chessie system fan]

Aren't you supposed to wear black socks with sandals like that?

You know, years ago I did wear white socks and sandals once.  It was for a Halloween party costume.  I had on my sombrero, a tie-dyed T shirt and a kilt.  I went as my inner self.   


Jason, I think narrowing the bottom coupler support on the outside and having that lip become part of the top was a good idea. 

[wcfn100]

So here's the picture from the weekend update again.



I was hoping to have some more, but I've been at the work bench trying to get an idea of what I've got here, and i think I have a good sense of it now.

First, the good news - it works and looks great.  I even have a new method for fusing the coupler that allows for much easier opening.  I put together some Kato Unitrack curves alternating left and right and there's enough coupler swing so far - haven't gotten to 90' cars yet - that there are no issues.  The couplers can be too far off center to not couple the first time without lining them up a bit, but to have enough swing, that's just going to be life for now.

The bad news - I don't think I can get around needed flat head screws.     I didn't want to have to use them primarily for cost as it adds about .50 cents per install.  I'm still in the testing phase, but it looks like the screw is always going to hover around the outer axle on most freight cars.  Passenger cars and freight cars with longer couplers won't have this issue.  I've been tightening the coupler down and grinding the head until it clears the axle, but that's not a good long term solution.

If anyone really wants to try these out, I'm comfortable making them public for purchase, just let me know.

Hopefully some more pictures tomorrow (I have some parts soaking now), and maybe even a video.

Rev. 3 looks like a slight change for a flat head screw, and I may possibly look at making the the hole for the screw into a slot which would give a lot more freedom when trying to install, especially when there's already holes from the factory in the same area.

Jason

[tom mann]

That looks great. I would like to try but I'll wait for Rev. 3.

BTW - what track is that?

[C855B]

Looks good to me as well. Since you have the pocket down I might impose upon you for a version that adds a plate for a glue-in option for Atlas ore cars. I need like 120 pairs.    (They'd sell like hotcakes, I suspect.)

... BTW - what track is that?

My edu-guess is M.E. weathered rail on Central Valley tie strips.

[wcfn100]

Looks good to me as well. Since you have the pocket down I might impose upon you for a version that adds a plate for a glue-in option for Atlas ore cars. I need like 120 pairs.    (They'd sell like hotcakes, I suspect.)

Once I get a couple critical dimensions figured out (see below), I'm  up for any conversion people want.  Are you thinking of a full width shim, or just a spacer the width of the coupler pocket?

I'll get the screws on order today and I need to build coupler height jig not only for the coupler but to determine the right floor height.  I have to wait on the redesign until I get the screws so I'll probably just experiment until then and hopefully have some more pictures.

Jason

[C855B]

An insert shim to fill the cutaway where the truck-mounted coupler box swings. Without measuring (calipers not handy), it appears the shim would be flush with the bottom of the end sill to get the correct height.



Don't do anything yet (obviously), this is still in the idea stage. I may do something that simply fills the cutaway with a pin that is a snap fit for the stock short MTL box.

[wcfn100]

Don't do anything yet (obviously), this is still in the idea stage. I may do something that simply fills the cutaway with a pin that is a snap fit for the stock short MTL box.

Just let me know, an adaptor for the ore car would be a breeze to do.  Here's a piece of .050" styrene (poorly) fitted in the gap.
 




Please excuse 40 years of dust. 

On a side note, if anyone is hoping these pockets will work with passenger cars on 12.5" radius, you can stop, they won't. 


Jason