Multi-part Tracks - Avoiding Poor Results

[inkpen]

I've recently taken to building AFV kits in various scales having been a largely military aircraft builder for some years.  Aside from older kits or the newer ones such as the Airfix Sherman Firefly and Tiger (which feature a choice between 'one piece' running gear and multi-part 'wheels and track', many kits feature tracks which are multi-part assembles featuring tracks broken down by individual 'links' or a mixture of individual links and track 'sections'. 

I must admit to having difficulty with achieving a satisfactory result using these multi-part tracks, specifically in joining these assembles so as to achieve the look of continuous track.  I find it difficult to avoid poor fit especially between individual links around the drive sprocket and tensioner wheels and from there to the generally horizontal upper/lower track lengths.

My approach to fitting the running gear as a whole has been developing over time and while improvements have been made results are still barely acceptable.  My current approach may be summarised as;

• to pay careful attention to teeth alignment or similar when assembling drive sprockets and tensioners - teeth or similar being aligned across the sprocket/tensioner
• to attach individual links to these assemblies before-attachment to the vehicle taking care to establish and maintain correct alignment of these parts in accordance with the previously aligned teeth or similar
• to dry fit the sprocket and tensioner enabling the 'multi-tracked' parts provided for [eg] the bottom/top of the track run, generally on a bottom to top sequence and once fit is established and necessary adjustment made then using liquid adhesive to affix the whole assembly

However careful I try to be, I find it difficult to achieve a good result especially between the upper/lower track and the track on the drive sprockets/tensioners.  

I have not formulated an approach to tracks featuring individual links yet, but I have a few kits where an injection moulded 'straight edge' is provided to help ensure the track links are correctly aligned but it appears to me that fitting the assembled track, or more likely parts of the assembly, would need to happen before the liquid adhesive drys which presents the danger of the track falling to bits on fitment and/or unintended sagging or breakage occurring following placement.

I'm sure there are 'tricks of the trade' which enable better results to be achieved and I wonder if any Airfix Club Members would care to share their approach - I'm certain there must be many!

[Tour de Airfix]

I’m just about to attempt this for the first time in years on my Airfix Churchill tank … will keep you posted! 😳

[peebeep]

Link and length is here to stay, I believe and in my view it gives you the opportunity to create a far more realistic looking track than rubber bands can ever achieve. It just requires a level of patience to get it to work. First off you need a tool to deliver a very precise amount of cement to fix the tracks together and I find the Pin Flow applicator by Deluxe materials is perfect for the job.

I use the wheels, sprocket and return roller as a jig. If you use cement to fix a few of the single pieces together, let it set for a bit, but before it hardens completely mould the links around the wheels or sprocket. 

You can actually cement the links in-situ with the Pin Flow, but because it delivers a tiny amount of cement  in exactly the right place the track won't stick to the wheels or sprocket, you can remove it and assemble it as a separate entity. 

With a little manipulation the tracks can be worked over the running gear after painting. Granted it worked on this Tiger model, but it may not work over different types or layout of running gear.

Link and length is pretty much de rigueur for new Braille Scale kits and a lot of the larger scale kits have them rather than complete sets of separate links. Having done one kit that required 198 links that each required several moulding gates to be cleaned up, personally I'm in favour of link and length! Also, it's the case that manufacturers are moulding upper lengths with built in sag.

 

 

[Ratch]

13 hours ago, Tour de Airfix said:

I’m just about to attempt this for the first time in years on my Airfix Churchill tank … will keep you posted! 😳

I think you'll find that's a Cromwell 🙃

Link and length are a great improvement on the old rubber bands.

[Tour de Airfix]

9 hours ago, Ratch said:

I think you'll find that's a Cromwell 🙃

Link and length are a great improvement on the old rubber bands.

Agreed .. my error 🤦‍♂️

[Tour de Airfix]

This afternoon I got to fit those circa 70 pieces of track to my CROMWELL tank. This is how I went about it:

1. Using a standard liquid cement, I glued the top and bottom pieces, including in this case, the string of 13 and 15 single tracks which I fixed to the top piece of track.

2. I left both pieces of track for about 30 minutes for the glue to take hold but not to let it harden solid.

 

3. I fitted the bottom track first, using the weight of the model to keep it in place and using the residual glue from the links to lightly bond this in place. With the tank sitting on the lower piece of track, II fitted the upper length, moulding the connected single links around the idler and sprocket wheels. I was then able to invert the model to apply glue to the two ends and secure them in place to complete the circle of track.

 

4. Once it looked OK from below, I flipped it back over and depressed the flexible upper track to sit nicely against the wheels.

5. I then repeated this process for the other side, such that by the time I had to return to the model the first track was sufficiently glued in place that it did not move as I flipped it over and around.

I will now leave them to dry and harden off over night and can then touch up and add further weathering as required. I hope this helps ... 😊

 

Edited April 28 by Tour de Airfix
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