Hey guys,

Scratchbuilding was definitely one of the things that drew me to modeling armor, and when I noticed that nobody makes a 1/48 scale M22 Locust, it gave me an idea to try it out. I've read a number of tutorials, and I have my references and most of the model planned out, except for the suspension which I need a little help on.

First off, the treads. The M22 used T78 tracks, which I have not seen any other tanks use. What is the best method for making tank tracks? I've read that they are the trickiest faze of scratchbuilding, but have not seen anyone actually mention how to make them.

My second question is about the drive sprocket. For the drive sprocket it seems as though I should create each one in three pieces (like the real one) and cast them individually, but I'm not sure how to go about carving out each tooth. Any advice?

My third and final question (for now!) is regarding the center part of the drive sprocket, the road wheels and the track idler, how should I go about those? The challenge for me would be getting a shape that's round and thick, while maintaining the spokes and other detail.

Pardon me if these sound foolish, but any help would be greatly appreciated. If this little project of mine ends up working out, I'll post the progress here. Thanks!

-Nik

Hi Nikalsen. I hope your M22 goes well, and I am definitely interested in seeing progress photographs. The tracks should be manageable once you make a good section which can then be cast repetitively. Mold rubber and casting resin would help tremendously.

The drive sprocket seems awful tricky especially for such a small scale. Here is another piece of material that would help: a fine drill with variable speed, so you can be slow and easy about the precise center of each sprocket curve. The outer sprocket ring would be drawn out on sheet plastic first. Keep replacing your knife blades so the sharpest edge will be ready to carve out those retangular inner hollows.

For the inner sprocket, and idlers, I would start by acquiring a variety of Evergreen styrene tube stock, and see which diameters might be most suitable--they can be cross-sawn and sanded to any kind of sliver. Also think about a compass…the circles might be slowly scribed out of thin sheet styrene, whether by needle pointed compass or by knife pointed compass. Lay up the slivers and cross cut cores.

A head-band magnifier glass would help keep the detail sharp for such a small scale.

You may already possess all the mentioned material. Scratch-builders often have a shop well stocked with years of accoutrements, so necessary to the craft.

Photos of my scratch-built Panther are accessible on the photo menu below my Armorama Avatar. I usually have to make everything twice. Do not be in a hurry, and always be willing to scrap the efforts that are less than suitable, to begin the better and more refined second piece.

Not surprising. The suspension is always the most difficult part of any scratchbuild.

As far as I know, they were unique to the M22.

Take a small caiber pistol, place it gently against your temple & pull the trigger. It'll save time later.

Scratchbuilding track is for crazy people or people who want to end up crazy. I know, I did it myself!



For something like the T78 track, the easiest is to find another tank with similar track (like one of the Japanese light tanks, perhaps) and just use them if at all suitable.

Actually scratchbuilding them in 1/48 would be brutally difficult. Seriously, nearly impossible. You need to have excellent measuring tools (like micrometers & digital calipers) and really good drawings. Make a base outline of the track & plan out the centre to centre distances of the track pin holes to ensure the pitch is correct. You can't be too precise with this. Remember, if you are even 0.001" out on the pitch after 125 tracks, you are out 1/8" in the track length and with this track pitch you'll need 2-3 links to make it up.

Produce a thin piece of plastic shaped like the base track platform (which is different on every track). Place small sections of rod on the base track platform to represent the places where the hinge points will be and ensure that everthing is square & parallel. After that has dried add the webs & surfaces that represent the treads and guide horns of the track out of thin sheet plastic. Once it's all good and dry, use Mr. Surface 500 to create the fillets & fill the seams in the link to represent a single piece casting.

Make a 2-piece mould & cast a few links. String them together & see if they a) fit, b) lay flat & straight and c) have the correct pitch. If not, fix what's wrong and make another mould & try another small string. Once it's right, make several moulds and then cast up all the track links you need. You can make a length of links and then cast that, but I have found that to be hard to assemble correctly, but it's up to you.



Get a drawing program for your computer (google sketchup in a pinch) and use it to create a drawing of the shape exactly as it should be. This is just about the only way to get the tooth pattern and pitch even unless your a pro draughtsman. I am and I still use the computer. Print 2 copies of the sprocket drawing in the correct size for 1/48 and stick them to a sheet of plastic the correct thickness. Use knives, files & other instruments of destruction to carve away anything that doesn't look like the sprocket. Create the central hub from an appropriate dowel. Cast all three pieces & assemble. Take special care that the teeth line up correctly otherwise you'll never get the tracks to sit even on the sprocket.

[quote]My third and final question (for now!) is regarding the center part of the drive sprocket, the road wheels and the track idler, how should I go about those? The challenge for me would be getting a shape that's round and thick, while maintaining the spokes and other detail. [quote]
Use a lathe. Barring that, find rod & tube of the right diameter & add a disc in the centre with a central hub added to the disc. Note that it will be a pure b!tch to get everthing centred & perpendicular. If things are not square the wheels will not sit properly in the suspension arms. The lathe works best by far.


The questions are not foolish, but if this is your first scratchbuilding project, you might be biting off more than you can chew with this suspension. The M22 idler is enough to make a grown man cry in 1/35 much less 1/48. Have you any idea how small those track links are? Itty Bitty don't come even close. The tracks are far an away the most difficult part of this.

Try to find tracks on an existing light tank kit that are acceptable then you might even be able to steal the drive sprocket. Even if you can't use it completely, you might be able to salvage the teeth & place them on a new diameter disc to get a new sprocket. The rest of the suspension is possible, even if really difficult in 1/48.

HTH

Paul