I'm trying to change the door knobs on some interior doors, which I thought would be simple but apparently not! Our doors are slightly slimmer than modern doors (35mm) and they have old latches that take a 7mm Spindle so this has not been as straight forward as first anticipated!
I managed to find some door knobs that fit the slimmer door size (https://www.hiatt-hardware.com/boston-m ... air-411579) only to find that the spindle they came with does not fit the latch in the interior doors. The spindle provided is 8mm but the latch takes a 7mm. I ordered a 7mm split ended Spindle (see pic) which fits the latch but the problem I have now is that the screws provided with the knobs don't seem to screw into this spindle - the one they came with has a 23mm x 3.5mm hole in each end to allow the screws to enter. As the 'split end' spindles seem to be the only style available to buy (that I can find) I wonder if anyone could advise on which type of grub screw might work to secure the outer/main part of the knob to the spindle. The current screws I have which fit the handle are metal, flat bottomed, Philips head (6mm Diameter), 4mm width x 12mm length. These don't work at all, they are too long and don't screw in.
I would be sooooooo grateful for any advice on this!