I like working on distressed HO steam locos. I have acquired a few here and there which had smoke box cover (SBC) issues. Some of the issues include the following: 1) the SBC is missing (a common problem on Rivarossi steamers; 2) the SBC is the wrong size (that is, too large or too small); 3) the SBC is glued to boiler and prevents access to the light bulb, locomotive weight or the fastener which holds the chassis to the boiler, or 4) SBC is not attached in a suitable manner.
On Rivarossi steamers, it is a simple matter to use a piece of sewing thread to attach the handrail on SBC to the handrail on the boiler (that is, a piece of thread on each side). OK, it is not prototypical. However, a missing SBC is not prototypical either.
It is possible to use a piece of stiff cylindrical foam or a piece of cork (maybe from a wine bottle) and attach it to the inside of the SBC. If the diameter of the foam or cork is a bit larger than the internal diameter of the boiler, the SBC should stay put but can still be removed for maintenance. It is also possible to make a disk with 3 or 4 radial prongs bent at right angles to the disk. The disk may then be attached to the inside of the SBC. I have seen something like this made from brass on Akane SP cab forward steam locos.
There have been a variety of after-market SBCs (various materials) made for steam locomotives. Perhaps someone utilized an SBC from a junk box or maybe something from the wrong locomotive. I have a beef if someone utilizes a smoke box cover which is the wrong size. It ends up looking kind of silly. In some cases, the diameter of the SBC has been altered (maybe the rivet pattern near the perimeter of the SBC has been removed). In other cases, the SBC diameter is too small which leaves the internal weight inside the boiler partially exposed.
I have a big problem if an SBC is glued to the boiler. This prevents access for maintenance and repairs. Removing the SBC may damage it or the boiler.
Because most after-market SBCs never seem to fit what I am repairing, an SBC can be fabricated from brass sheet, tin can stock or paperboard. I have trouble trying to find SBCs for American Flyer 0-6-0s. In this case, I use a drawing template or a coin and mark out a disk with a razor blade or a sharp pencil. The disk may be cut out as needed with scissors if the stock is thin enough (approximately 0.005 to 0.010 inches thick). Then I cut out short strips of metal and glue them on to the SBC in a radial pattern to simulate the SBC dogs. I also attach a pair of horizontal strips on one side of the SBC to simulate the hinges. I have even fabricated simple pilot light enclosures.
Attaching the dogs and hinges to the disk can be tedious. This is because aligning the small strips of metal is not a simple matter (that is, teasing the strips into position with a modeling knife or a straight pin before the glue cures). In addition, it is a good idea to scrape the surfaces of the tin can stock with a razor blade or the glue may not hold.
Some SBCs are not flat but are dish-shaped (that is, convex). This is the case on UP Big Boys and some of the older steamers. The bottom of an aluminum beverage can may be cut out as needed to make a dish-shaped SBC.
I have a big problem if an SBC is glued to the boiler. This prevents access for maintenance and repairs. Removing the SBC may damage it or the boiler.
