Using adhesives to assemble Parliamentary Trains kits.
As part of the Parliamentary Trains programme of continual improvement, we have conducted trials of a variety of adhesives. There are various types which may be used in the assembly of our kits, but we have come to the conclusion that our own favourite is one of the oldest. Fish glue, also sold as Seccotine, is a ready to use viscous liquid which can be applied with a brush at normal temperatures. It can become very thick in cold conditions. It becomes tacky after a minute or so, at which stage small parts such as buffer bases, axlebox layers, strapping and so on can be put in place. The application of finger pressure should then be sufficient to hold them as the glue dries. Larger parts or overlay layers should be clamped. The glue manufacturers recommend clamping for 12 hours, which is no doubt appropriate for heavy wooden structures, but for small models a much shorter period of an hour or even less is adequate. If the glue dries before the joint is made it can be reactivated by wetting, or applying more glue. Excess glue can be removed with a damp cloth or paper towel. This glue is water soluble so if it dries in the brush it will soften in water. With large areas it can be helpful to apply glue to both surfaces, letting it dry on one and bringing the parts together when the other is tacky. Fish glue is classified as nonhazardous.
We recommend priming our models after assembly and before painting with French Polish (shellac dissolved in alcohol) which is waterproof and will protect against dampness. Fish glue is suitable to use on a wide variety of materials, including metal parts such as bearings. Note that it does not stick well on painted surfaces, so if you need to fix painted sub-assemblies together it is best to scrape away paint from the mating faces before gluing.
We have also built our kits using a thin (runny) grade of cyanoacrylate (superglue), which is an alternative for rapid assembly of the main structures, but take care - these adhesives will rapidly stick your fingers together and should be kept away from children. An odourless grade is much less likely to cause problems of nasal irritation. This kind of adhesive is by no means ‘instant’, even with the help of a liquid cyano activator, which we prefer to apply with small cheap brush which makes it easier to control where the liquid goes. Where possible parts should be left clamped in place and the glue allowed to set solid. This adhesive is easy to used for fixing small metal parts as it will run through the joint with the parts in position. However, joints made with this type of glue can be somewhat brittle and might possibly pop apart if bent or subjected to a shock load.
For the attachment of some of the smaller parts and such items as strapping, a tacky white glue (PVA adhesive) is another possibility, applied with a small stiffish brush - don’t let the glue dry in the brush or it may spoil. Bear in mind though that PVA glue does not stick well to itself. Paper towels are useful to mop up inadvertent excess of either cyanoacrylate or PVA.
Most parts are retained in their sheets by tabs (usually one or two), which can be cut through with a robust craft knife. Any remaining traces of the tab can be tidied up with abrasive paper. To avoid loss, leave the parts in the sheet until needed.
A further warning when modelling generally - don’t solder near parts joined with superglue. The fumes are most unpleasantly acrid and doubtless poisonous!