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Flat blade screwdrivers

Discussion in 'd.i.y.' started by Tony L, Feb 1, 2019.

  1. Vinny

    Vinny pfm Member

    I am 99% sure that there is no specific name for thin blade drivers, but more expensive ones SEEM to have thinner and better, squarer ground tips, and to be a far better compromise on hardness/softness/brittleness.
    There is no point in my measuring the blades of my Kennedy drivers as they are 10++++ years old, so an obsolete type, but they are thin and extremely well/precisely ground. If you can get to somewhere selling good quality (expensive) drivers, 99.99% of them will allow you to give anything a close look-see if it isn't already on display and open to having a try - just take a problem setscrew with you.

    As suggested, I think you are just looking for expensive drivers, not a particular type or brand.
  2. 337alant

    337alant Negatively Biased

    Good thread Tony, I agree that flat head screws can be a pain.
    I like the look of those Grace gunsmith screw drivers that Tim linked too and I would say that you should be able to find what you need from there

  3. timH

    timH Senior Moment Member

    Just multiply the inch figure by 25.4 to get millimetres. So .038” = 1mm (as near as damn it)
  4. Tony L

    Tony L Administrator

    Bizarrely I found I do actually have a screwdriver that fitted the smaller slot I illustrated well, a Wera, so this particular job is now done - scope completely disassembled, cleaned, relubed, rebuilt and I think working as it should! 50+ year old grease really is remarkably nasty sticky stuff! Thankfully the screws were not tight (I’d left it sitting on the radiator for a good while which may have helped). Didn’t chip the paint at all so a good result.

    Still very tempted by a set of the Grace screwdrivers, they look like nice things and I suspect are what I’m after (I know nothing about guns, but many date from the era I am thinking of). I’m just deciding which set to go for.
  5. timH

    timH Senior Moment Member

    I’d suggest a .22 rather than a 457 magnum - oh you meant screwdrivers.
  6. westsea

    westsea Retirement present

    Still very tempted by a set of the Grace screwdrivers, they look like nice things and I suspect are what I’m after (I know nothing about guns, but many date from the era I am thinking of). I’m just deciding which set to go for.[/QUOTE]

    Tony, try googling specifications for slotted screws or screwdrivers, it throws up many variations. I think the critical measurement is the width of the slot, a set of feeler guages will help you measure this, available in metric or imperial, although period equipment is likley to be imperial. Length of the slot is easier to measure, a six inch steel rule from Axminster tool will probably good enough. The simple approach is the one you suggest, buy two or three Grace scredrivers around the size you guess needed and work from there; the specification is good. The parallel tip is important to avoid cam out. You have probably got there already
  7. Kraus

    Kraus Member

    It might be worth checking a gunsmith - I recall their turnscrews as emphasising the required characteristics for this, precise, usage.

    They may be made in small enough sizes.
  8. Tony L

    Tony L Administrator

    I have another related terminology question:


    If you look at the concentric focus knobs on the microscope you will notice a grey painted cap with two holes on it. What is this, or more specifically the tool to remove it, called? I have managed perfectly in this case with a pair of appropriately-sized circlip pliers, but I have a few examples of this type of screw knocking around on various things so would quite like to know what they are called and what the correct tool to deal with them is. The correct tool may even be circlip pliers for all I know, but without having a clue what the threaded disc thing is called I can’t google it!

    PS Realising that I liked my larger set of Wera screwdrivers I bought this set of Kraftform Micro. They landed earlier today and look very good indeed, really nice quality, thin blades and a good range of sizes/types. Much nicer than my existing set of (Chinese I think) precision drivers and surprisingly good value at under £30. I still fancy trying a set of wood handle gun screwdrivers and I also want to find a nice used example of the GPO screwdriver at some point. I have no issue with buying multiple tools!

  9. timH

    timH Senior Moment Member

    That looks similar to the thing on an angle grinder and also circular saw. Might be called a collet spanner
  10. Barrymagrec

    Barrymagrec pfm Member

    Pin spanner.
    gavreid likes this.
  11. Tony L

    Tony L Administrator

    I can see that is the sort of thing, but they seem to be massive and for bike bottom brackets, angle-grinders etc. I’ve not been able to find any little ones. I suspect there must be another term for the sort I want. They are very widely used on cameras too, e.g. holding the film-winder, self-timer etc on.
  12. mmckernie

    mmckernie pfm Member

  13. wow&flutter

    wow&flutter pfm Member

    Pin spanner / face spanner I think. Did Avondale not use those sort of fixings on the facia of their amps/ power supplies at some point? Can’t find a pic at present.
  14. Tony L

    Tony L Administrator

    Despite well over half an hour googling, eBay & Amazon searching etc I’m not seeing anything that isn’t huge and designed for angle-griners, car engines etc. I’m beginning to think the circlip pliers I have are actually the right tool!
  15. Rug Doc

    Rug Doc pfm Member

    Tony, those are called snake eyes. :)
  16. demotivated

    demotivated pfm Member

    If you had some pointed tweezers, such as a watch repairer has, the 2 points will often fit in these holes and then held with pliers it would turn. Only works for low torque parts. Bike parts are usually loosened with a narrow tool in one hole and a regular tapping with a hammer. Obviously this is a bit destructive.
  17. timH

    timH Senior Moment Member

    You can get circlip pliers for external circlips that have the prongs at 90 degrees. They usually open outwards when the handles are compressed but some are reversible. Some come with a selection of different diameter prong heads
  18. Tony L

    Tony L Administrator

    The circlip pliers I have, a decent quality German made pair with nice round pins, are a good fit with this particular part, certainly better than other the options I’ve seen so far (e.g. ‘snake eye’ drivers look to have square prongs that would chew up the pin holes). My question was curiosity as much as anything as a really nicely purpose designed tool just doesn’t seem to exist. I found a thread on a camera forum yesterday with folk trying to make a tool from the smooth back end of tiny drill bits and epoxy, so I’m clearly not the only one looking! Another tool that maybe has potential is a lens spanner - I could do with getting one of these for its intended use anyway. Someone really needs to design a tiny little adjustable spanner with a series of installable pins of different diameters. There is clearly a demand!
  19. cooky1257

    cooky1257 pfm Member

  20. Tony L

    Tony L Administrator

    The minimum distance is too large for so many of this type of fitting. As an example check out the self-timer knob on my ‘67 Nikkormat:


    This type of fitting is common on classic cameras, which is why I’m so stunned there doesn’t seem to be a specific purpose-designed tool available today. It obviously needs to be an absolutely perfect fit or one would risk irreparable damage.

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