Instrument screwdrivers

[Justin Passing]

I need to take some microscopes apart. The screws are all slotted, but
a) have very fine slots and
b) are not tiny e.g. from 4 - 8 or 10mm

The screws are generally pretty soft, and chrome plated, so they damage easily. The blades have to go all the way into the slots. Most don't go in.

I think I'm going to have to grind larger screwdrivers down, unless anyone knows a supplier?

They need to be full screwdrivers, not replaceable insert type, because of access.

 

[Mottie]

I use these for removing/adjusting bracelets on my watches. Not cheap but very good.

Starrett S555z-7 Jewellers Screwdriver Set Of 7 from Woodford Tools

Starrett S555z-7 Jewellers Screwdriver Set Of 7 from Woodford Tools

www.woodfordtools.co.uk

 

[blup]

If you search portable mini screwdrivers on Amazon zon you will find a set for under £5

 

[jj4091]

Maybe

https://www.screwfix.com/p/magnusson-mixed-precision-screwdriver-set-6-pieces/8645V?gclsrc=aw.ds&gad_source=1&gad_campaignid=21550393591&gclid=CjwKCAjw-8vPBhBbEiwAoA39WiWE4rY04SHvXpiNj8et1F7TT584z8gGpIVOex1MNKC_B6zyNtEAUhoCPMIQAvD_BwE

 

[Justin Passing]

No that's not what I'm looking for - I meant thin slots, not small sizes.
I have Bergeon screwdrivers for watches which go from 0.4mm up in 0.2mm width increments but stop at under 3mm.
I want
"not tiny e.g. from 4 - 8 or 10mm"
The screws might be say 6mm wide, i.e. a very common size, but the slots are very narrow, less than 1mm.

Iirc BT used to have a spec for thin slots, but they may have done away with it.
I'm sure I've seen sets in half or one mm increments of width, but I've looked in horology suppliers etc.
One microscope I'm, working on must weigh 30kg. Not microscopic!

I found a spec, it appears I need Form C
chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://cdn.standards.iteh.ai/samples/35869/8172b254f966470ab774a4c0a99231a2/ISO-2380-1-2004.pdf#:~:text=This%20part%20of%20ISO%202380,operated%20screwdrivers%20for%20slotted%2Dhead%20screws.

those are flat at the tip not wedges, bur not particularly fine either
I found some screwdrivers listed at ESSKA which are of standard dimensions but you can at least check the blade thickness.
I'll have to start with a decent material screwdriver and grind it carefully...

PB Swiss and Wera seem to be the best quality out there

 

[denso13]

No that's not what I'm looking for - I meant thin slots, not small sizes.

Gunsmith screwdrivers? Normal widths but thin tips...

Narex Gunsmith Screwdrivers

These screwdrivers are perfect for making adjustments to planes or other tools fitted with slotted machine screws. They were originally designed and intended for the fine adjustment of firearms which required great control without the risk of damage....

www.axminstertools.com

 

[Justin Passing]

@denso13 Thanks, those are the best so far, I'll get a set, or maybe two sets, one for fiddling with!

I've been thinking how to "make" what I need.
If I can clamp a screwdriver down I should be able to use a Dremel cylindrical grinder. I've found with things like this in the past that it's very easy to get a taper on the workpiece that you don't want.
I thought about brazing a piece of "silver steel" into a slot on the end of a rod, but it's surprisingly difficult to get "silver steel" in flat form.
Silver steel; is just carbon steel, but it's strong and brazable. Stainless steel isn't , with fluxes I have.

Maybe I could use little bits of Stanley knife blade or scraper blade, cabinet scraper blade, hacksaw blade... evenJunior hacksaw blade for skinny ones.. Little bottles of chinese flux are cheap.