Grub Screws

[allenlondon]

I have a couple of grub screws, hexag tops, in typically inaccessible places. I want to replace them with Philips-headed screws, easier to locate and turn.

How do I measure the grub screws? Or can I just buy an assortment of grub-screw type bolts with Philips heads?

Ta.

A

[Theland]

Tell your supplier what size Allen key, (hex), you use on the grub screw, they will be able to tell you the diameter from that.

[allenlondon]

Not sure Amazon offer that sort of old-fashioned service.

[Old_Geezer]

Any use https://www.google.co.uk/search?q=grub+screw+sizes&tbm=isch&source=iu&ictx=1&fir=F6qPHXGXBmLuQM%253A%252CTi1HuRpNdNNmCM%252C_&vet=1&usg=AI4_-kTz9pdtEE9w_aB_7dJMlD2m8Ptq8g&sa=X&ved=2ahUKEwj_sI-6kqTmAhW5TxUIHczBBTMQ9QEwAHoECAQQAw&cshid=1575742583002&;biw=1101&bih=1530#imgrc=F6qPHXGXBmLuQM:

[KARL]

You want to change to Philips ?? That is the one type on which the leverage is most easily "stripped" (you cannot turn the screw/bolt because there is no longer any purchase to be had). Presumably the grub screws need to be properly tightened - personally, I would avoid Philips like the plague as I much prefer Torx or (second) Allen and if really pushed even the simple slot would be better than Philips. When you say hexagonal tops do you mean classic hex-bolt or Allen as Theland has read ?

[KARL]

If you really want to go ahead then you simply measure the diameter and length, always assuming these are modern i.e. with standard metric thread.

[Hymie]

Theland’s suggestion is good; looking at this wiki-link (see table of spanner (wrench) sizes – last column for grub screws) by measuring the allen key you can read across yourself the metric thread size (first column).

https://en.wikipedia.org/wiki/ISO_metric_screw_thread

[allenlondon]

Thanks.

Hymie: yes, that chart might be handy.

They are old-fashioned allen-headed grubs, like these:
https://tinyurl.com/u4w95t9.

Bit more info. I can't see. I'm disabled. The screws I can't access are very close to the bathroom tiles. I can't get underneath to look up at them, I can only feel my way to them with my fingers. Screws, philips screws, might have disadvantages, but the big advantage is that you can guide a philips screwdriver to them, and (gently) turn them.

An allen key has to be SPOT ON - a nats the wrong way, and it won't go in; a nats not the right angle, and it won't go in. Hence the need for a little philips 'grub' screw.

Allen.