Stearman trainers were delivered from the factory with a convex rearview mirror. Many of those original mirrors have been broken over the years and have been replaced with flat mirrors. The field of view in a flat mirror is very restricted… like looking through a soda straw. The convex mirror with its wide field of view is a vast improvement. Not only can you see your front seat passenger but you can admire you own dashing good looks too! In formation flying the convex mirror is particularly useful in that you can even see your wingman behind you in certain maneuvers when he would otherwise not be visible.
My ship had a flat mirror when I acquired her and I looked for a long time for a suitable convex one. On the rare occasions when I saw a stock one for sale the price was so high that it squelched my desire to change from flat to convex. After much searching I finally found a new-production truck mirror that was easily adaptable to the Stearman and with a slight modification of the rubber grommet it fit the stock rearview mirror housing perfectly. The mirror, Model #610146, is a 5” truck mirror made by Retrac Mirrors. I purchased mine for about $8 from a company called Fleet Pride, a truck parts supplier with 220 locations in 40 states. If they don’t have a store near you I’m sure you could order the mirror on the net.
Here’s how to prepare the Retrac mirror for installation in the Stearman: Start by removing the upper and lower halves of the mirror housing from the upper-wing center section of your aircraft. Next, take the new mirror and using a sharp razor blade carefully cut off on a 45º angle the lip of the rubber grommet that protrudes beyond the the metal housing around the mirror. Do not cut the front off the grommet or it will no longer hold the mirror.
Now, make several small hacksaw cuts about one inch apart through the outer periphery of the metal backing, starting from 9 o’clock then about every inch or so around to 4 o’clock. In other words, these cuts should include slightly more than half the circumference of the mirror. The purpose of these cuts is to allow you to bend up the “tabs” you’ve created and remove the mirror and its rubber grommet from the metal housing. The metal is quite thin so use a fine-tooth blade and be careful – it doesn’t take much to cut through it. In cutting the tabs you will probably find that you end up cutting into the rubber slightly. Try to keep the cuts in the rubber to a minimum by working from the back side of the mirror when cutting the metal, and don’t cut any deeper than you need to to penetrate all the way through the metal. In the end, if the cuts into the rubber grommet are not deep they‘re of little consequence and won’t show once the mirror is mounted in the aircraft.
Next, carefully insert the blade of a small flatblade screwdriver into each cut and successively pry up the metal until you can grasp it with pliers, then bend the tab up 90 degrees. Be careful not to put a load on the glass while prying or bending or you’ll crack it and have to start over with another mirror.
After bending up the tabs you’ve created around slightly more than ½ the mirror you will be able to remove the glass with its attached grommet and you can discard the metal backing. Next, check the fit of the mirror/grommet with both the upper and lower mirror housings. Chances are you’ll find that the mirror/grommet assembly is still slightly too large in diameter and slightly too thick to fit properly into the groove in the housing. This next step can be accomplished with the grommet on or off the mirror. Using a sharp razor blade, reduce the thickness (front-to back) of the grommet by approximately 1/16” (or however much you need so it will fit nicely inside the slot in the mirror housing). To do this cut lay the grommet down on the bench and use a sharp (new) razor blade to carefully trim the grommet thinner. The cut should be made on the back side of the grommet – the side that will be away from the “business” side of the mirror. This will leave the front (visible and finished) side of the grommet undisturbed.
To reduce the diameter of the grommet so it will fit the housing sand the outer periphery of it evenly and carefully down to the proper diameter. Test it periodically for proper diameter by placing the grommet back on the mirror and slipping the entire assembly into the mirror housing to see how it fits. If you’re careful you can leave the grommet on the mirror during sanding. It’s easier to sand the grommet while it’s on the mirror because that gives it some backing and support. I used a belt sander with 80 grit paper and it cut the rubber nicely. A disc sander would work equally well. Again, don’t stress the glass. You probably won’t have to take too much off the diameter of the grommet… perhaps 1/16”+/-.
Once the grommet is sized so that the mirror fits properly in the upper and lower housings combined, place it in the lower housing and run a generous bead of silicone calk along the enclosed side of the joint, bonding the mirror, grommet, and metal housing together. This will prevent the mirror from moving around in the housing.
Once the mirror is installed in the lower housing, check to see that the small drain hole in the bottom is open. If not (it may have gotten clogged up by the silicone), take a small drill and re-open it. Reinstall the upper half of the mirror housing in the wing and once in place reinstall the lower housing/ mirror assembly into it. Next time you fly I think you’ll be pleased with this mirror. It’s a vast improvement over a flat one… and it looks authentic.