Gloster Gladiator


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Maestro aeromodeller Doug McHard shared yet another one of his amazing creations in the July 1971 AM.

In spite of his didactic qualities I wonder how many of us ever succeeded in achieving his results – he rose the bar to unattainable heights.

At 1/36 scale the Gladiator is not quite “Peanut Scale” and I took the liberty of enlarging the PDF available on Outerzone to 13 inch span.

This will be my third attempt at building this model. The first one (1980) went over 18 grams, was not airworthy and accordingly scrapped. Number two (1992) was around 12 grams and made short flights in Belgium and Nottingham but something was dismally wrong. Doug himself commented “it should float around” but unfortunately the words were spoken in a bar and not in the flying hall where he might have been able to give the model a critical eye. Number two was given to a child in the UK. For some reason I never photograph unsuccessful projects – denial?

Below is an impression of the Aeromodeller article and building instructions.

So here we are in 2016, still trying to build a McHard Gladiator. First up are the molds for the laminated wingtips, fin and stabilizer.

Whether this construction method is really lighter than the alternatives is debatable. It certainly is not quicker, but the results can be neat and above all crash-resistant.

Once the laminated outlines are satisfactory, their internal structure can be inserted. In the meanwhile, the ribs cut from 1/32 inch sheet are pinned between their templates, uniformly sanded and slotted for the spar. There are 5 different rib sizes, and at stressed positions 1/16 inch thick balsa is deployed.

Below the lower wing is assembled, using the laminated wingtips and previously prepared ribs.

The picture below shows the upper wing with its tips propped up in order to obtain the required dihedral. Sanding the leading and trailing edges to shape is a painstaking task that takes longer than the assembly.

My scale could not measure the individual masses, and so the 2 tail parts are weighed together.

Doug McHard's original had separate port and starboard stabilizer halves individually fixed to the fuselage. Having followed his guidance twice I now take the liberty of simplifying matters by making a single unit.

A hard 1/16 inch square stick was used as a spar for the lower wing – the second picture of the upper wing reveals the penalty.

The picture below shows the two fuselage side frames being constructed one above the other. Creating identical parts that also follow the plan is quite a challenge at this scale – the relatively strong light over the dining room table is seldom sufficient and many a detail require revision.

Compared to the original plan the rear rubber mount was moved forward one bay and also raised a little. On the cutting mat the many bulkhead parts can bee seen: they will give the basic square fuselage structure its rounded shapes. In order to keep track of their identity their paper templates are pinned to them.

Struggling on, I wonder how I ever managed to do all this twice before.

The engine cowling is a tiny barrel built up from balsa discs, rings and about 40 1/16” sticks.

The painted cowling on the right was made back in 1980 and could have been used but I wanted a better one.

The Gladiator's narrow wheels need careful construction if they are to run true. Mine are bushed with thin brass tubing and have a dowel collar for additional support. The tube enables turning in a Dremel power tool. Once satisfied with the result, the excess tube is cut away. Adhesive is thin cyano that saturates the soft balsa immediately around the tube.

Hub caps are pressed out of thin plastic sheet. The original 1980 “special tools” still suffice.

Doug McHard specified “five thou” acetate for the cockpit canopy and other molded plastic parts. My 6 thou material is 20% out!

Fuselage and engine/cowl.

Getting all the shapes between the fuselage and the bottom wing right is perhaps the most difficult detail in this build. In the first 2 cases I recall fudging this with blue foam and soft block. This time the instructions were followed (1/64” sheet).

Here you can (perhaps) see how it fits together.

0,4 mm (1/64”) balsa sheeting ...

Cabane struts support the upper wing at the exact incidence required. The struts were set up in two steps, one side at a time. The wing was temporarily supported by the card template in the middle and a stooge on one side while I fiddled with the first two struts on the opposite side.

The card template idea comes from the ffscale.co.uk site and takes a lot of pain out of biplane wing alignment!

An all-time favorite step in my model plane construction is tissue-covering and especially the moment when the floppy paper goes tight. Below, the wings and tail are pinned down overnight to the fibre board while the diluted dope dries. The nitrate shrinking dope is thinned to a watery substance and a few drops of castor oil mixed in as a plasticizer. A fine, soft flat brush is used, of which only the tip is dipped into the mixture, carefully brushing lightly in all directions.

The cardboard template between the fuselage and the upper wing plays it's final role of assuring the wing's correct position and stance as the glue between the struts and the ribs dries. The two wingtip templates are less important but nice-to-have.

The cockpit canopy is basically a clear plastic bubble pressed out of heat-softened sheet using a plug carved from block balsa. My 0.15 mm sheet was sourced from A4 office transparency material. Thicker material will be too heavy!

The hole in the plank is just a few millemetres oversize all around. Note the rounded edges that permit the softened plastic to follow the mold as it passes through.

A (preferably old) toaster is an ideal heat source for small molding jobs like this one. Do not burn your fingers or drop drawing pins into the toaster and remember to heat the side that the plastic sheet was pinned to until the plastic goes floppy.

The first pass is generally a practice run to get the knack of things once again, but soon enough you will be rewarded with a good pressing. The most common error is insufficiently warmed plastic.



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