N scale turnout build with proto:87 parts

[ednadolski]

Thanks Gary that looks like a way more robust approach than a butt joint.  Just to be clear: you solder both point rails to that pulling throwbar in this manner, is that correct?   But doesn't that render the primary throwbar redundant (except for the linkage to the switch machine)?

Soldering both point rails to the same throwbar would create a rigid structure, but that seems OK since you have the P87 heel block joiners which permit movement.

BTW - that primary throwbar is delrin (or some other plastic) and not PCB?

(Neolube... I'll have to try that)

Thanks!
Ed

[GaryHinshaw]

Thanks Gary that looks like a way more robust approach than a butt joint.  Just to be clear: you solder both point rails to that pulling throwbar in this manner, is that correct?   But doesn't that render the primary throwbar redundant (except for the linkage to the switch machine)?

Yes - that is correct.  And yes, the primary throwbar is then somewhat redundant, but the etched clips serve nicely to push the thrown point firmly against the stock rail.

Soldering both point rails to the same throwbar would create a rigid structure, but that seems OK since you have the P87 heel block joiners which permit movement.

That's correct.  If you use hingeless point/closure rail assemblies, this rigidity may be an issue, but in that case you might not need to solder the point rail to the pin/throwbar.  I had to with my hinged points because the points would not remain vertical without doing so (the heel block is pretty loose).  But you would then need some mechanism to keep the points from riding up too high on the stock rail - the etched clips on the primary throwbar could probably prevent this.  However, I suspect that a solderless approach would not be very reliable.

BTW - that primary throwbar is delrin (or some other plastic) and not PCB?

Black styrene.  I took some .040 sheet stock and cut strips, though I wish I could find some pre-cut strip stock in black, because it's kind of a pain to slice thin strips off the thick-ish sheet neatly.

-gfh

[ednadolski]

Thanks for the info Gary.   Good point about the clips to keep the point rail from riding up.   Seems that could be more of a concern with the P:87 CNC milled points, since with those the stock rail base may not be filed away.  However I have seen those ride up with filed points too  (also the P48 cast points, if not filed on the back side to fit against the stock rail).

Ed

[ednadolski]

Taking a closer gander at those last pics, it looks like you are now removing the base of the stock rails where the point rails meet.   Did you find this necessary even with the planed p:87 points?  (which are ostensibly supposed to avoid notching, but don't necessarily work out that way in practice - ymmv).

What do you think of the P:87 heel blocks?   I can't say that I am totally sold on those, they fit rather loose.

Ed

[GaryHinshaw]

Taking a closer gander at those last pics, it looks like you are now removing the base of the stock rails where the point rails meet.   Did you find this necessary even with the planed p:87 points?  (which are ostensibly supposed to avoid notching, but don't necessarily work out that way in practice - ymmv).

I do indeed notch the base of the stock rail now with a Fast Tracks stock rail thingy (and always did, in fact).  It's likely possible to make the P:87 points work without doing so, but I was never comfortable with the fit, and I saw no real disadvantage to notching.

What do you think of the P:87 heel blocks?   I can't say that I am totally sold on those, they fit rather loose.

Mezzo mezzo.  I like the way they fix the closure - stock rail spacing and create a pretty rigid structure between them.  The slots for the rail web could stand to be narrower, but they work fine for me.  Note that my throw-bar+2-point-rails assembly forms a rigid structure that simply slips into place in the heel blocks.  Here is a fuzzy picture of the previous version of that assembly:



The new version is similar, but with the pinned throw-bar.  (The longer throw-bar is detachable and is just resting in place in this shot.)   The main point here is that the point rails are rigidly vertical, and they just slip into the heel block and pivot freely.  Note that I use a stack of two heel block etches for code 55 rail, to minimize vertical play.

-gfh