20-02-2021, 12:39 PM
You will rarely remove the screwed in plugs in a block without drilling them out.
I have just removed the plugs from 3 blocks.
Drill or mill out the plugs to about 7/8" to 1" diameter then drill a series of holes in the remainder. Collapse the annulus with a hammer and chisel and retap M32 x 1.5 which has worked well. I can confirm the thread is 1 1/4" x 16 tpi however one of the blocks has a 1" thread
Its important to get all the rust out of the area of the plug thread and for this I use Citric Acid, 1kg of crystals to 8 litres of water and after a couple of days you are left with a lovely clean grey surface. If you want quicker action just keep the solution warm.
This is much nicer to use than molasses and Muriatic acid.
I haven't had the new plugs made yet but they'll be in SS and have two dowell holes rather than a screw driver slot and sealing will be by o ring.
If there was enough interest I may be able to supply some of these to third parties.
Jim Runciman
I have just removed the plugs from 3 blocks.
Drill or mill out the plugs to about 7/8" to 1" diameter then drill a series of holes in the remainder. Collapse the annulus with a hammer and chisel and retap M32 x 1.5 which has worked well. I can confirm the thread is 1 1/4" x 16 tpi however one of the blocks has a 1" thread
Its important to get all the rust out of the area of the plug thread and for this I use Citric Acid, 1kg of crystals to 8 litres of water and after a couple of days you are left with a lovely clean grey surface. If you want quicker action just keep the solution warm.
This is much nicer to use than molasses and Muriatic acid.
I haven't had the new plugs made yet but they'll be in SS and have two dowell holes rather than a screw driver slot and sealing will be by o ring.
If there was enough interest I may be able to supply some of these to third parties.
Jim Runciman