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Scouseget

Screwdriver Sharpening

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Hi. 

When I first started in this hobby, I decided not to go cheap on the tools so bought really good quality tweezers and screwdrivers, etc. This leads me to my question on screwdrivers which is that as  the screwdriver set I bought (there are 9 of them in a rotating holder) and came with multiple replacement blades for each size, I assumed then that when a blade chipped, I just junked it and put in a replacement blade, however due to my inexperience I found I was replacing them really often, and in fact soon had to order more of the smaller sizes so:

1). Is this the right approach, i.e., just junk any damaged blades and replace them with new ones and if not, why not considering how cheap the blades are?

2). If I should be sharpening them, can I use a diamond stone as I already have a set of these that i use in my furniture making hobby? I also have water stones - would these be better?

3). I watched a YouTube video yesterday from the AWCI, which stated that not only should a screwdriver be just the right width for the screw slot, it should never bottom out in the slot but rather sit just above it so that the screwdriver actually jams up against the slot walls, which will prevent it slipping out and damaging the screw and/or screw hole. Is this correct because I assumed that the screwdrivers, especially given how expensive they were, would be inherently designed like this? Does this mean that even replacement blades should be adjusted on a stone to assure that they do not bottom out, and what if some screws have shallower slots than others for a given width, should I then customize the screwdrivers to ensure the correct fit?

I should mention that, although I'm getting better at it, I still have screwdrivers slipping out of the screw slots and wreaking havoc, well at least on my ego, if not the movement itself.

Should you have any other advise regarding the maintenance of screwdrivers, I'd love to hear it.

Thanks from sunny Edmonton, which is now being subjected to a plague of mosquitoes thanks to recent heavy rains. And we thought we were going to escape that pleasure this year!

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I regularly repair my blades with a stone and oil. I use a small device to hold the blade at the correct angle - widely available on ebay and other places for a few bucks. Not sure if a water stone would give same results.... I find #3 interesting. It makes perfect sense that you would not want your blade to bottom out - but I've never thought about it like that. Don't know how practical that is, but I'm going to pay attention to that detail from now on. I always seem to run into some nice blued screws with a particularly wide slot - and those things are quite slippery!!!

shapren.jpg

 

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screw driver sharpening is a art.   you want 100% contact between the blade and the screw slot - otherwise you wil bugger up the screw head " look up tool and knife sharpening"  it takes  practice.   basicly,  the  tip is hollow ground,  on a grinder then  flattened to size on the wetstones (  3 grades available).it takes time to do a good job. a video would be nice.   vinn

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For sharpening the blades I always used an arkansas stone with a little 3 in 1 oil with the same tool that sstakoff has posted. It takes a lot of practise to get it right. If you're like me when I first tried I messed up many. Make sure you have the correct size blade for the screw again its practise, first make sure you hold the screwdriver dead upright and not leaning to a side, master that and your screwdriver won't slip out of the screw slot.

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Like others on here I don't restrict myself to just one set of screw drivers. I have one set ground to a thinner profile, and another set ground to a slightly fatter profile. I also have numerous screw drivers ground to extra thin and extra fat.

As a rule I find that Swiss screw slots are thinner than Japanese, Quartz movements tend to have a few have extra fat slots, very old pocket watches seem to have extra thin slots.

This sounds like an expensive investment in screw drivers but I have probably spent less on my multiple sets than many others have on just one as I have picked them up second hand and in job lots from all over the place. They are good quality, vintage, French or Swiss. They don't necessarily have the silkiest smooth ball bearing tops to them but they are perfectly functional.

If you generally work on the same type of movements (pocket watch, or Japanese, or Russian for instance) then one set of screw drivers tailored to that specific family of watch movements is all you need.

As for throwing away old blades it does seem a bit of a shame. Generally speaking all that is needed to bring a chipped blade back into trim is 5 minutes on a stone (or decent quality wet & dry paper on a sheet of glass, or your diamond stones).

If you find that you are regularly suffering from chipped blades then it might well be worth exploring the possibility of adjusting the temper of the blades. If you get it right you not only get more resiliant blades which are less likely to scratch movement plates, but you also gain an understanding of heat treatments for steel on a macro or even micro scale. Useful stuff.

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the reason you should "hollow grind" just a bit : is the screw driver point will be  "wedge shaped" and will not give 100% contact in the screw slot, but that's why some buy new  blades.

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All I mean is to make sure the tip is perfectly flat. You don't want to sharpen the angles of the blade like a knife blade, to an edge. When you break a tip, you are getting into thicker metal the further up the blade you go. When you sharpen them, you need to do both sides of the blade at the angle which will thin it back out and then sharpen the very tip at a 90 degree angle, as flat as possible with a very fine stone, to get the width you need to match the screw head openings. That's all I mean when I use the term "blunt".

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On 6/21/2016 at 1:57 PM, Marc said:

 

If you find that you are regularly suffering from chipped blades then it might well be worth exploring the possibility of adjusting the temper of the blades. If you get it right you not only get more resiliant blades which are less likely to scratch movement plates, but you also gain an understanding of heat treatments for steel on a macro or even micro scale. Useful stuff.

This makes perfect sense, however I have a couple of questions regarding this:

Why on earth don't they come correctly hardened and tempered, given that this was a very expensive set of screwdrivers?

How should we go about doing this, i.e., what type of torch should be used, what color should we heat the steel up to for each step, what is the quenching medium, etc? 

Regarding the sharpening of the screwdrivers, it seems to be agreed that the tip of the blade shouldn't touch the bottom of the screw slot, thereby ensuring that the blade jams against the side of the screw slot thus helping to prevent it slipping out - am I right in this or is this some fanciful notion that idealists propose whereas the real practitioners don't actually do this but rather have sufficient dexterity to ensure it doesn't slip out even when the blade bottoms out?

If we really should ensure that it doesn't bottom out, then can I assume that, providing the blade has been properly sharpened and sloped, then all we need to do is grind the bottom back sufficiently until it clears the bottom of the screw, and should we do this each and every time we encounter as screw with an extra wide slot? 

There's a lot to this hobby isn't there? Who would have thought we would be learning metallurgy, sharpening, heat treatment,  etc., and that's just for the screws, then there's the movement itself - yikes! Or at least crikey as Steve used to say!

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27 minutes ago, Scouseget said:

This makes perfect sense, however I have a couple of questions regarding this:

Why on earth don't they come correctly hardened and tempered, given that this was a very expensive set of screwdrivers?

Good question. If you notice, "haute holologierie" at some point is an exercise in rationality twisting, or futility. A perfect 1st world timekiller / moneymaker.

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If the screwdriver blade isn't supposed to bottom out in the screw head, that is one rule I break with regularity. Every screw I've driven in my life has had the driver blade bottom out. I'll continue that way. I don't have a problem with the blade coming out while turning.

Sent from my XT1585 using Tapatalk

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I spent the day literally watching paint dry. I was using black lacquer to fill in the engraving on a pocket watch case to make it stand out. I will send pictures when it is finished.

In the mean time I was looking for screwdriver sharpening stone holders on the net. The sticker shock was amazing.

So i said to myself, "Self" your only watching paint dry, make your own, you have a sharpening stone and some wood. So I made this from scrap wood while watching paint dry. I'm happy with it & it cost nothing. It is perhaps not as pretty as Bergeon but they have enough money. 20161012_110004 (Small).jpg

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very nice tool ! it is a good way the make the  flat sides paralel.  a usefull tool to find [ or invent] would be one that hollow ground the tip before honing.   part of the concept of "100% contact in the slot"  vinn

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