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Regulator screws
Hello people
Anyone know what the spec. is for regulator grub screws?
Ruby mark 2
Also are they the same for the lighting/ignition switch ?
PS screw dia. is 2.2mm
There’s some on eBay just now

Bill G
Based near the Scottish Border, 
Lucas tended to use brass grub screws with BA threads for terminals, if that's what you are after.
People then merrily overtightened them "just in case"
Even numbers are preferred, such as 2 BA and 4 BA, but you will need to measure one to be sure
If you are stuck, grubscrews can of course be fashioned from conventional brass BA screws chopped down and then slotted.
It looks like 2.2mm is 8 ba
I have 2BA grub screws in stock (BG115s).
(13-01-2019, 11:11 PM)David Cochrane Wrote: I have 2BA grub screws in stock (BG115s).

My problem is how to get one out of the A post on the fuse-box! I have tried soaking in penetrating fluid and all I have done is (almost!) destroy the slot! I worry in case the post starts to turn!
I am nervous about applying heat in case I melt something and don't want to try & "spring" the slot open to ease the pressure on the thread (I gave seen many of the posts opened up in the past!)
Any ideas other than carefully drilling the grub screw away?
I too have had problems with brass slotted grub screws !
Just starting a rewire so much interest in your difficulty.
I have missing grub screws hence my question on screw sizes.
By the way ignore my dimension (2.2mm) completely WRONG having a senior moment.
I think diameter is 1/4”

Also have found grub screws with Allen key socket these are very easy to remove/replace.
Trying to find a source for these.

Try GT 85 fluid to release your screws.
Also had some success with hot air gun gently applied.
Good luck
You can apply heat accurately and relatively delicately by cleaning the available surfaces and resting a soldering iron (with a blob of solder on it to transfer the heat) on the parts needing to be heated.

Usually the two sides of the terminal can be "sprung" can be a little, and closed up again afterwards, without lasting damage.

Original Lucas regulators are made of Bakelite which is fairly heat resistant.  Don't get out the oxy-acetylene, but 100 degrees C from a hot air gun should be OK. 

Otherwise it might be a case of some "Dremel Dentistry" until the screw is hollowed out enough to collapse inwards.

Or, this might be one of the few cases where a left-handed screw extractor actually works ?
I could imagine that a left handed screw extractor (which, I should make my position clear, are the work of the devil) would tend to expand a brass grub screw and push out the sides of the terminal. I don't think I would be tempted to try that route...

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