Looking forward a bit I need to start thinking about casting the polyurethane tyres on the return rollers and the road wheels. This process is new to me so I have done a lot of research, talked to those who should know and I think that I have a plan that should work. I am going to start with the return rollers and have decided that a mould that forms the outside diameter and the front angled face to finished dimensions would give the best results and reduce the amount of post casting machining.
I don't have any material of the required size so being a skin flint I have welded four 8mm thick plates together two and two the turned the joints at 90 degrees to each other and puddle welded the plates together.
This is the kit of parts for the mould. The plates were then bored and turned so that they run true and the angle for the front face turned in. A centre shaft turned to locate and bolted in the base plate.
The hub is the placed over the centre shaft and a spacer sits on top of the hub. This spacer seals the top of the hub and forms an air gap. A top plate is placed on top of the spacer, this has pouring holes cut in it and is turned to the same diameter as the base plate, which is the finished diameter of the roller. A tin outer cover is then wrapped around the outside thus forming the finished outside diameter.
Jubilees clips, top and bottom of the mould hold the outer sheet in place and finally the whole assembly is bolted together.
The polyurethane, release agent and vacuum chamber are all currently in bound, all I have to do before commencing the casting is to shot blast the hubs and add some extra bands around the outside of the hubs to increase the surface area so that the tyres have a bigger area to bond to.
It would comforting if you posted a picture of something you’ve made that isn’t amazing just to assure the rest of us that you’re mortal. Always look forward to your updates.
Believe me Dave, I have made enough mistakes in life as it is but this dream is my world and I make the rules. What's not to like.
One of the members of HMVF thought that the steering box oil filler cap looked over engineered and toooooo modern, he suggested that I use the same design of cover as used to cover the radiator filler cap on a 251 half track. Is this more acceptable, I think so.
Looking forward a bit I need to start thinking about casting the polyurethane tyres on the return rollers and the road wheels. This process is new to me so I have done a lot of research, talked to those who should know and I think that I have a plan that should work. I am going to start with the return rollers and have decided that a mould that forms the outside diameter and the front angled face to finished dimensions would give the best results and reduce the amount of post casting machining.
I don't have any material of the required size so being a skin flint I have welded four 8mm thick plates together two and two the turned the joints at 90 degrees to each other and puddle welded the plates together.
Nice looking bead on that butt joint
Give a man an opinion and you feed him for a day,
teach a man to use the "search" function on the WAF and you feed him for a lifetime.
It needed to be strong as it would be rotating at 680 rpm with mw stood in front of it while I was machining it. I don't like the idea of large lumps of metal flying in my general direction.
The drivers escape hatch has always been a component that I have been looking forward to making, the locking mechanism seems overly complex but was an interesting assembly to construct.
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