Notes on building an EM Finetrax 1:7 double slip.

[John CutlerParticipant]

Let me say that I am not an expert track builder. I have built a dozen turnouts using C&L parts but not terribly well.  One B5(Y) is in its 3rd (still unsuccessful; not flat enough!) reincarnation and will be partly replaced by this 1:7 double slip (hopefully with fewer complaints from the Maunsell N). I judge building a double slip from C&L components as being beyond my skills, hence the acquisition of the Finetrax kit.

 

This is not a kit for the first-time point-work builder. If that is you, first make one of Finetrax’s simple turnout kits.

 

Unless you are a skilled track builder, I recommend having some C&L chairs to hand for repairs. These need to be cut down to shape against the Finetrax web; I suggest both C&L slide and ordinary chairs and gluing with superglue. My kit arrived with 2 stock rail chairs missing (in different locations). I was prepared for this but you may want to inspect carefully on receipt for possible return to the seller. The Finetrax chairs are brittle.

 

The paper instructions supplied with the EMGS product refer to the diamond crossing rather than a double slip and are potentially misleading; hopefully this only applies to the first product batch. The instructions have now been updated and are much clearer; download the pdf file from the Finetrax website. Make sure you have the Finetrax template as a guide (print off the pdf file if you did not get a paper copy from the EMGS). My suggested sequence of assembly differs slightly:

 

1.       Work out the electrical connections and isolating gaps as shown in the downloaded Finetrax instructions. This helps you understand why and where to leave isolating gaps and when to test for electrical continuity. You also need to plan routes for the wiring leading away from the slip. If you are going to differ from the suggested scheme you need to plan how it will all work -Good Luck with that!

2.       Unless you propose to leave it in a horrible dark colour, lightly spray the sleeper web with grey primer. It is so much easier to paint over a light colour than dark. I then painted the sleepers with a dilute wash of my desired acrylic paint colour. I do not bother overpainting the sleeper ends; the grey primer is OK for those bits sticking out from under the ballast. I caution against over-painting the chairs at this stage as it could make threading rail through them difficult and cause damage; the chairs are much more delicate than C&L’s.

3.       Insert the central V rails (K crossings). I decided to lengthen these rails compared to the template so that the isolating gap is hidden inside the next chair. I hate unsupported gaps in mid-air, engineering-wise and visually. It also invites vertical steps in the rails. This means you must measure and cut the rails to length carefully.

4.       Now make up the tie bars with pins and lay them onto the webbing. If you leave this to later like me, you have to force the pins under the closure rails (or the switch rails) and will probably damage chairs. It is wise to tin the end of these pins with solder now for use later.

5.       I do not think it a good idea to assemble the switch blades now. Avoid possible distortion to them by assembling the awkward closure rails first. Measure up the closure rails from the K-rail gap to the knuckle and cut. You need to be careful and try to get this right first time; do not rush! The closure rail needs to end halfway through the knuckle chair. Because the wing rail will meet it there later, try to put a corresponding angle on that end of the rail so they will butt snugly. The instructions tell you that insertion of these is awkward as you have to gently bend the web down so the rail clears the top of the frog. Remember after cutting to prepare the rail so it inserts easily and to have the tie bar in place before inserting. I had to reinsert 2 of the closure rails and on both occasions damaged chairs; they are delicate! After assembly, the whole structure is still floppy and a bit delicate; keep it flat.

6.       Now insert the crossing V-rails followed by the wing rails. Be careful that the wing rail does not force the closure rail to close the isolating gap with the K-rail. I checked for lack of electric continuity and dripped super-glue into the chairs at each end of the closure rail to try and stop the rails moving.

7.       At this stage the web is still quite fragile; try not to bend it. After preparing the stock rails to length, bend them slightly until they roughly adopt the curvature of the template; we want to minimise stress on those delicate chairs. Once the stock rails are inserted, the web feels a lot more robust.

8.       Now the switch blades can be cut to length and inserted. Double-check the length before cutting; it is easy to get this wrong. Note the ends meet inside a chair. The outer ones can butt up against each other but the inner switch blades need to be isolated from each other. After testing for lack of electrical continuity if appropriate, fix the ends with a spot of superglue before any soldering.

9.       Ensure the switch blades lie flat; weigh them down or hold them down whilst soldering to the tie bars. Now using 145̊ solder, not 188C, solder the ends of the tie bar pins to the inside of the web of the switch rails. If you have not already done so, tin the ends of the pins before soldering them to the rails. This helps use a minimum of solder and minimises the time the iron is near plastic. You really need an iron with a very small tip for this job. The objective is for a minimal solder joint within the rail web. If you end up with solder anywhere on the rail top or upper inside, you need to clean it off to allow for uninterrupted running of both wheel treads and flanges; = much cussing from me and careful application of a fine flat file. For me this was the worst part of the job. Do not throw away the spacers used to ensure there is a running gap between the open switch blade and the stock rail; because the solder joint is minimal, there is a chance this will come adrift in service and you will need them for any repair (a certainty in my case!).

10.   Fix the check rails in position. Mine were fairly loose so a spot of superglue was applied to the middle chairs.

11.   Test for running with a Short-Wheel-Base 4-wheel wagon. Why is mine never smooth? I used a fine flat file to smooth out some slight vertical steps. Because I broke some chairs, I replaced them with cut-down C&L chairs. These mostly protruded above the rail height so had to be filed down level. A tiny piece of epoxy resin applied to the top of rail gaps can act as a filler to level the rail height and also help to maintain any isolation. File down level after hardening overnight.

12.   If the complete assembly does not lie completely flat, place on a level surface and leave under a pile of books overnight, making sure the bottom one is large enough to cover the whole thing.

13.   Turn the double slip over and solder electrical connections to the bottom of the appropriate rails. Note that the inner switch blades should not just rely on contact with the closure rails for electrical continuity; Finetrax’s wiring diagram is not clear on this. Install a wire to each frog from the pair of switch blades; a slack silicone wire is preferable so it does not interfere with the flexing of the switch blades. I filed a shallow channel under 3 sleepers to take a wire from the frog to the closure rails at the knuckle.

14.   Now is probably the best time to paint the chairs, rail sides and check-rails etc with a rusty colour, although some may prefer to paint in situ. If you use acrylics, they are easy to scrape off the rail surface before they harden; I also scrape paint off the inner top edge of the rail so wheels can pick up current from the flange radius as well as the tread. This painting takes a lot of time; over 3 days for me. Some people successfully spray or slosh paint over the whole thing and then scrape the top rails. I have seen superb examples of this but also a lot that look truly awful as if the track is covered in sludge. Why does no-one (the EMGS?) produce a rust-coloured conductive rail? Surely a brass/nickel/bronze alloy is feasible? Then the tops of chairs could be painted before assembly and conductive silver paint applied afterwards to the rail tops.

15.   Before laying in position, check and adjust the height of the neighbouring trackwork. The sleepers of this double slip are 1.8mm deep so are slightly thicker than EMGS standard thick ply sleepers (at 1.7mm actual v 1.5mm nominal). Remember that a vertical step of 0.1mm equals 1/3” on the real thing, which would probably be unacceptable on passenger lines (my double slip is in a yard so I have no problem with that!).

16.   Test again with rolling stock before finally fixing. Also check that electric continuity is where you want it and not where you do not want it! Problems will be much easier to solve now than after everything is fixed in position.

17.   After fixing, test under power. Locomotives seem able to find jolting vertical steps more readily than most rolling stock. Be prepared to flatten or file level.

 

I managed to break one of the tie bars trying to push it underneath closure rails that were already fixed in place (clumsiness and poor procedure). Fortunately Finetrax supplied a replacement (Thank you Wayne).

 

Apart from this, my casualties were 11 damaged chairs. Of those, 2 were missing on arrival, 4 were broken due to reinsertion of closure rails and 3 from trying to insert the tie bars. You can avoid the latter by following the suggested procedure above and laying the tie bars in place early. Intriguingly all my breakages were on the outside of the rail. Until I tried to join the slip with neighbouring track when I broke a 12th chair on the inside of the rail; I suggest fixing fishplates to the slip first.

 

I hope the above helps. I am not sure I would want to use this kit for a layout to be regularly exhibited. I am a bit concerned whether the chairs will survive regular passage of the heavy Bachmann N mogul which, against buffers, has propelled rails across the room in one fit of temper! Would the isolating gaps or plastic chairs survive large variations in room temperature or in transit? I am not qualified to judge. The biggest deficiency of the kit is how brittle the chairs are. No doubt technical advances in 3D printing materials will reduce this issue in the future. This should not deter the apprentice track builder. As long as you are careful and take your time, you should end up with a good result. After all, nobody can be as cack-handed as me!

 

Finally, the Finetrax kit, despite some drawbacks, is good value for money. Unlike some competitors, it faithfully replicates the prototype in its geometry. I suggest that even for expert track builders, these kits give a faster build, especially if there are a lot of turnouts to be made on a layout.

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