Armour Dreams

[Jonathan Moore]

On the Tubes there is a little boss that locates in to a slot in main optics housing.
When the unit is assembled, if you turn the knurled boss, the split pins only there as a temporary measure, the vision tubes move closer together or further apart to suit the driver.

[Jonathan Moore]

As you can see the unit hasn't be set up properly yet.

[Jonathan Moore]

The next job is to get the sprocket flanges welded together and machined and as I do not have a lathe big enough, the machining will have to be done on a milling machine. I have a rotary table but I don't want to damage it, so I needed a rotary device that wasn't going to cost the earth and as usual my mind started to look at Land Rover components. I decided on a stub axle and hub from a Disc 1, it would need modifying but it would do the job.

[Jonathan Moore]

Rotation will be via my arm and a long 1/2" drive bar, a health and safety nightmare I know but I have used the method before and as long as a lot of caution is used, it works well. Bolt the whole assembly to a nice thick bit of plate, add some bolt down holes and all is ready. It also came in handy when I welded the plates together.
I then turned the bottom flange so that it runs true with the top plate just to make positioning it on the main plate easier before welding.
It's now all welded together ready for machining.

[Jonathan Moore]

The machining of the sprocket flanges went well but I forgot to take pictures when they were on the machine and by the time I thought about it, I had tack welded the sprockets on.
The sprockets should be and will be, bolted on to the flanges but first I have to machine a recess in both sides, so that the sprockets sit over the outside diameter of the flange. My cunning plan, is to drill the 60 lightening holes and 20 retaining holes in each sprocket but rather than drilling the retaining holes as clearance holes drill and tap them. Then by bolting from the rear of the flange I can utilize the retaining holes to hold the sprocket to the flange, then machine the recess in one side of the sprocket flip it over and machine the recess in the opposite side. Well that's the plan.

[Jonathan Moore]

I have been drilling flipping holes, I am even dreaming about the things. Next it's the fun job of machining the recesses.

[Jonathan Moore]

All the holes have now been drilled so it was on to the machining of the recess in either side of the sprockets. To start with I counter bored the flange and then tapped a number of the holes so that I could bolt the sprocket in place rather than just relying on my tack welds.
Again I used the modified Land Rover hub but by using a spring loaded stop I turned the whole assembly into a sort of ratchet. If you remember I am rotating the assembly by hand using a long bar, so if the cutter were to snatch, especially at the start of each cut, it would try to rotate the sprocket at the speed of the cutter (500 rpm) in the opposite direction to the one that I am trying to turn it, taking my arm with it and ending in a big bang. As you can see from the pictures, the stop rests against each tooth of the sprocket in turn, stopping it rotating in the wrong direction and as the sprocket is rotated the stop moves accordingly.