Its been almost three months since I have been able to tackle the re casting of the lid due to my poor method of mixing the lid. I used a trowel and never really got any interchange between the Perlite and the fire cement. It was only after learning that the best methodology is to use your hands like a really big cake mix!
I used two pairs of disposable gloves (one on top of the other) when handling the mixture and had the bucket and lid at a comfortable working height. In the end I had just enough materials to cast the lid and also included a plug formed by an old Pot Noodle pot. Just need to have it set off now for a few days.
Suitably recharged I thought I should tackle the hinge for the lid. I decided to use a couple of scrap bits of steel from the scrap box. The outer tube is from a handle that was 'saved' from somewhere..... I thought I would mill a slot that would require the lid to be raised, before revolving the lid outward and then dropping into a holding slot slightly higher than the closed postion.
The inside bar then had a 6mm metric thread tapped into it so a grub screw could be inserted and act as the pin (see photo's below). The outside tube will be welded to the steel casing of the furnace. The lid part of the tube will be cut later and the bar then welded to the top part.
The lid can then be lowered into the base part welded to the main casing and the grub screw then inserted allowing the hinge to operate. We shall see......
The remaining tasks are now as follows.
1                 Weld the hinge to the lid and base.
2                 Make the fitting to attach the burner to the furnace
3                 Make a stand for the crucible to stand on inside the furnace.
4                 Make up the sand boxes to hold the casting sand.
Then fire up the furnace and see what happens! It shouldn't be too long before that happens and certainly within the next fortnight I would hope.