Although BA fixings are making a come-back now I don't think you can (as yet) buy BA socket heads so you need to make or contrive…. The two methods I have used successfully are to use a non BA with enough diameter to turn down in the lathe and then recut in BA….this makes for ratehr large head which may not be what you want.

The other method is to turn up the blanks and using a simple jig, forge the socket head using an allen key, then thread BA…this sounds tricky and time consuming but I found this to work well in practice. The jig I used was part of plate from a scrapped machine which had recessed openings for the right sized bolt with sunken heads. You need to turn down the head when made to give a good finish.

Kevin

If the holes are not yet drilled/tapped my choice would be to go with M2.5 grub screws which are readily available in all end forms.

Emgee

If your holes are already drilled/tapped, I suggest you ignore them to drill and tap new ones that will fit the grub screws that are readily available. In the future you will appreciate the convenience of having a common item.

A spot of Locktite will make up for a compromised thread engagement.

Great thread – slotted grub screws are so troublesome that even Meccano has dropped them.

.

Are you sure that they haven’t simply switched over to M4, Mark ?

MichaelG.

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Answering my own question:

https://www.meccanoindex.co.uk/Drawings/Pimage.php?Nmbr=134&Co=&Pno=0

Edited By Michael Gilligan on 09/11/2021 17:01:04

Try ba-bolts.co.uk