Check rails loose jaws option on COT track

[Vistisen]

Hi Martin I can see that when printing COT turnouts you have already created an option for loose outer jaws on the Vee crossing, this is an excellent feature. Would it be possible to do the same think with the jaws on the angled checkrails? This would enable people to avoid having to thread them thought the chairs. The outer storck rails are not a problem. I have tried to show what I mean here:

 

[Martin Wynne]

Hi Martin I can see that when printing COT turnouts you have already created an option for loose outer jaws on the Vee crossing, this is an excellent feature. Would it be possible to do the same think with the jaws on the angled checkrails? This would enable people to avoid having to thread them thought the chairs. The outer storck rails are not a problem. I have tried to show what I mean here:

View attachment 13626

@Vistisen

Hi Tim,

All this is known about and under development, see my post:

https://85a.uk/templot/club/index.php?posts/16186

When it's fully ready you will be able to set the outer stub jaws option which you want for any chair, in the chair heaving dialog.

In the meantime we have:

But we are not there yet -- I can only go so fast. It's a constant battle of wits to avoid folks jumping ahead of me and confusing beginners with what is and isn't part of plug track.

p.s. one of the flared check end chairs will be solid-jaw. This aids construction by holding the rail in place while you glue on the remaining jaws. 2-part epoxy recommended. Use bent paper-clips as rail clamps in the usual way while the epoxy sets. This is the same as the one or two solid-jaw chairs at the wing rail front rail joint.

cheers,

Martin.

 

[Vistisen]

I can see that all the things I have asked for are already in your plans. I am quite happy to wait.

 

[Martin Wynne]

p.s. one of the flared check end chairs will be solid-jaw. This aids construction by holding the rail in place while you glue on the remaining jaws.

@Vistisen

Hi Tim,

After further testing I have changed my mind on the above. It requires the check-rail end to be pre-bent to exactly the correct angle, otherwise it prevents the rail sitting snugly in place while the glue sets. It is easier to test-fit the bent check rail with none of the jaws in place.

So all the check rail jaws will be stubs. They go outboard of the rails on the existing timber webs:

Note that the left and right angled stub jaws are not interchangeable with the parallel CC stub jaws. The jaw rib is angled to fit between the chair screws.

What I can't make up my mind about is whether this option should be on by default for the check rails? Anyone?

Many builders find the FDM chairs are sufficiently flexible to allow threading of pre-bent check rails (for the REA flare angle at least). This option would then be required only for pre-grouping check rails with sharper flares. Maybe also if anyone is resin printing COT track.

cheers,

Martin.

 

[Hayfield]

Certainly in 7mm scale pre-bent rail slides through the check rail chairs without any breakages.

I think both the build and design process will probably differ between scales with COT track. As it seems the larger you go in scale the strength or the chairs increases

For instance in 4mm scale you need to use clips to hold the track bricks in place, however in 7mm scale due to the strength of both rail and chairs I have found there is no need for the clips. Like wise as I said the strength of 7mm chairs allows a bit of elastically of the chair parts

Martin, I must say you have pulled out all the stops again with a wonderful bit of code and printer settings. As usual words escape me, thank you on behalf of all railway modelers

John

 

[Martin Wynne]

So all the check rail jaws will be stubs. They go outboard of the rails on the existing timber webs:

p.s. Just to add that if you want to use the dropper-wire retainers on these timbers, you will need the on tab option in the shove timbers, to clear the stub jaws:

The stubs get snipped off during construction of course, to clear the ballast.

• The above shows the THIN timbers option. You can see that the retainers won't hide below the ballast with the THIN timbers -- they are sensible only with the MEDIUM and THICK timbers options. In fact ballasting the THIN timbers option will be tricky, needing fine ash ballast as found in yards, goods loops, etc.

Martin.

 

[Vistisen]

@Vistisen

Hi Tim,

After further testing I have changed my mind on the above. It requires the check-rail end to be pre-bent to exactly the correct angle, otherwise it prevents the rail sitting snugly in place while the glue sets. It is easier to test-fit the bent check rail with none of the jaws in place.

So all the check rail jaws will be stubs. They go outboard of the rails on the existing timber webs:


View attachment 13645


Note that the left and right angled stub jaws are not interchangeable with the parallel CC stub jaws. The jaw rib is angled to fit between the chair screws.

What I can't make up my mind about is whether this option should be on by default for the check rails? Anyone?

Many builders find the FDM chairs are sufficiently flexible to allow threading of pre-bent check rails (for the REA flare angle at least). This option would then be required only for pre-grouping check rails with sharper flares. Maybe also if anyone is resin printing COT track.

cheers,

Martin.

I think that sounds like the right way to go about it. My latest test on COT in 4mm shows that the chairs are quite robust. But whether they could put up with having angled rails pushed through them (possibly several times if there is need for adjustment) has yet to be tested by me. Though I can quickly give it a try on my test track by bending a few rails to suitable angles, it that helps.

By having the solid half of the chairs on what I Imagine to be the critical side in terms of clearances, It will be easy to test fil pre bent rails.

At the risk of again suggesting something that you have already thought of, (and I have tried to search the forum but not found any posts hinting at it this time!) what about a jig for the knuckle on the outer vee rails and the checkrails. I envisage the flat block of plastic with railed sized grooves that follow the profile of the rails for these components. So that one can test pre bent rails to see if they fit in the groove.

I also have a suggestion to try and save you time, effort and frustration, Martin. I think that a Status post pinned to the top of the plug track section that has a list of all the various bits that you have done (but not yet released), plus things you are working on, are planning to do at some point, plus things you have thought about but rejected. This would hopefully avoid you having to repeat yourself all the time in posts.

I suggest that it should be in the form of a table in that gets updated when relevant, it could contain a STATUS column and even a column where links to relevant topics in the forum. This would hopefully avoid us all pestering you

I am not up to date on the progress with the Wiki, but such a page might be best put there with links to the forum for more information.

 

[Martin Wynne]

At the risk of again suggesting something that you have already thought of, (and I have tried to search the forum but not found any posts hinting at it this time!) what about a jig for the knuckle on the outer vee rails and the checkrails.

@Vistisen

Hi Tim,

Already available for the knuckle bend (strictly a gauge, rather than a jig tool -- see below for Phil's bending jig):

The cut-out in the top surface shows the extent of the actual bend radius. The actual output also has the crossing angle marked on the gauge (not shown in this render).

Nothing specific for the check rail flares, but easily created as above by setting the control template crossing angle to 1:18.

Above can be resin or FDM printed.

Also a simplified version can be added to the crossing filing jigs (half rail-depth in each part). FDM only:

@Phil G has kindly posted a resource for an actual bending jig/tool:

Info at: https://85a.uk/templot/club/index.php?resources/knuckle-bending-jig-for-code-75-4mm-scale.23/

Thanks again Phil.

A status web page sounds a good idea, but only if it is kept fully up to date. Which means yet more work for yours truly -- all previous attempts at such things have failed because I simply forget to update them, or even that they exist, sometimes for years at a time.

I will see what I can do. Quite often I work on things which are complete failures, so announcing in advance that I'm working on them would cause a lot of confusion. I could add a note afterwards that I tried them and failed.

Thanks for your thoughts.

cheers,

Martin.

 

[Vistisen]

THanks again. I thought I had searched for it.. but not enough

 

[Vistisen]

I think I have reached the limit for what is possible for me with COT in 4mm. The loose jaws option gave me a fine print where all full chairs worked perfectly. It took literally a couple of minutes to assemble the stock rails, But the separate jaws did not work for me. The holes in the timbers were too small and not deep enough. I had difficulty clipping the loose chairs free. The cutters deformed the plastic enough for it to be impossible to fit them in the sockets.

What I would like to try, is to use COT for all the chairs which do seat angled rails, and Plugin sockets for resin printed chairs for those that do. I know that I am pushing forwards quicker that I should be. But I hope that my experiments can possibly save time later down the road for other people.

I am not sure whether it is possible to mix COT chairs and socket chairs on the same template?

When I have choose COT track, clicking on the control template chair settings button still brings up the experimental chairing menu. If options made here have no effect of COT track, then it might be better for the menu to be disabled when COT track is selected. If the experimental chairing menu DOES still have relevance, then it would be nice to have ‘create clip socket’ option for each chair type.

Another thing that might need fixing is that although the window size can be changed, the content including the scrollable list does not fill the window.

I can see that it is (OF COURSE) already possible.

I just needed to look... and wait for the next release Sorry to waste your time Martin

 

[Martin Wynne]

I think I have reached the limit for what is possible for me with COT in 4mm. The loose jaws option gave me a fine print where all full chairs worked perfectly. It took literally a couple of minutes to assemble the stock rails, But the separate jaws did not work for me. The holes in the timbers were too small and not deep enough. I had difficulty clipping the loose chairs free. The cutters deformed the plastic enough for it to be impossible to fit them in the sockets.

@Vistisen

Hi Tim,

You have completely lost me.

1. COT track for 4mm/ft scale has not yet been released. NONE of the settings are yet implemented to make it work properly. How you have got anywhere at all with it is a mystery to me?

2. The loose jaws option is intended ONLY for resin printing, plug-in chairs and thick timbers. It won't work with FDM printing below about Gauge 3 (13.5mm/ft scale).

3. In FDM prints there are NO holes for the jaws to fit in. The small holes in the chairs are recesses for the glue to be applied (2-part epoxy recommended) when fitting the stub jaws.

4. I don't understand how you can be distorting anything if using the sharp flush cutters which are supplied with most of the printers? Or with any other electronics type snips for that matter. What filament are you using? The intended filament for all Templot plug track, COT track and filing jigs is toughened PLA+ (PLA-Plus). I'm getting the best results with the Sunlu brand, rather than some of the lower-cost brands. Specifically this one (I have posted this link several times):

https://www.amazon.co.uk/gp/product/B07Y5K1TB5

This filament can be cut cleanly with the snips without any distortion.

5. The chair heaving function is not yet working properly. I have mentioned this several times. It is all still experimental and should be improved in the next update (556b) soon. Lots of other experimental stuff is also not yet fully working:

---

It's great that you are conducting your own experiments with 3D-printed track. But please don't reference it back to Templot because it just confuses everyone -- including me.

cheers,

Martin.