20mm hole 25mm gland

[Gavin John Hyde]

I am looking for some sensibly priced thread convertors so that I can screw my 25mm compression glands to the convertor/adaptor to then use the existing 20mm holes. On Andersen chargers there is a 20mm hole for cable entry and its a very tight squeeze to get a drill or cone drill bit in to enlarge without risking damage to the plastic core, its the sort of plastic that would under the right tension/force just crack

Was using a pile of Wiska ones but my suppliers are now saying out of stock or £2 ex vat each... which for a bit of plastic seems excessive

AM i missing something obvious - have thought about a metal fixing but not found somebody with stock.. suggestions and suppliers welcome

 

[MJPD29]

The same wiska one is about 80 or 90p online I believe if you can order it there. Think I got them from tlc