Ultra thin screwdriver

O.K. The words "width" and "thick" should have sufficed.

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Yes.

Adjust the rests down out of the way (or just temporarily remove them) and you can get at the curve on the top front of the wheels.

It is generally a lot tougher than mild steel at least. Heat and quench and it will be too brittle. And a good screwdriver is not seriously hardened for the same reason. Cheap ones can be either mild steel which will never harden, or carbon steel which may be too hardened and likely to break under serious use. (I've seen both.)

*Seriously* good screwdrivers are likely be forged steel, and ground to final dimensions.

But if you heat and quench, you will have something too brittle, and will have to re-heat to draw the temper back to something more reasonable.

Almost nothing is produced full hard -- tools need to be tough as well as hard.

From what I have heard, they are good -- but I have never seen ones which I knew to be Brownells.

But really -- try making something before you spend all that money shipping things across the big pond. You will probably discover that it isn't nearly as difficult as you appear to think it is. And each one you make will be that much easier than the previous one as you gain experience.

Good Luck, DoN.

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Yes -- about. Maybe down to 60 degrees or so. The shank is resting against the lip of the toolrest as he described it, with a slid-on collar resting against the toolrest to keep the extension of the screwdriver blade long enough.

Enjoy, DoN.

The feeler gage sets from the auto parts store have a nice hard feel to them. Maybe a bit of the 0.025" leaf cut and ground, held in an Exacto knife handle, would be just the thing, and renewable.

For that matter, I just checked an Exacto knife blade, and guess what:

0.025" thick!

Correction, properly named X-Acto here in the USA.

Brownells is THE standard for quality gunsmithing tools and supplies. I can't imagine buying anything from them that is not good quality, perhaps exceptional quality.

I think an X-Acto blade would be too brittle. They aren't made for torsional stress.

Find the closest size you can, and then make it smaller with a whetstone or a diamond hone.

This way you can hold the flat edge of the screwdriver against the stone and bring it to the proper thickness and width gently and are not likely to over shoot your target, nor overheat the steel.

If you do get it a little too thin, you can just dress the end back a bit and be in business.

I expect they are knife stock which is hardened and tempered, which is about what you want for a miniature screwdriver. I don't think "brittle" is the relevant material property.

Right. Got it. Richard said "drill stop just resting under the tool rest". It was the word "under" which confused me.

I don't have any drill stops, though. Are they a good investment? I use a depth scale on my bench drill, which works some of the time, but it is possible to overshoot when using it.

Best wishes,

Chris

I was just thinking that "length" and "width" could not be interpreted as being the same thing, whereas "width" and "thickness" could be. Never mind. It didn't work!

You don't think there's a chance that the screwdriver will end up in my chest, if the tip catches on the wheel?

I discovered this when I tried to turn and tap drill rod. It was rather difficult.

The best screwdrivers I have are a set made by Wera. Nick Mueller recommended them. They make the other screwdrivers I have look awful by comparison. The just fit the screw heads so precisely.

I am still thinking about the Brownells set. Having looked at the articles I want to work on, I figure that I need about six thin screwdrivers right now. If I buy six good screwdrivers to grind, it will cost a significant proportion of the cost of the Brownells set, I might mess them up when grinding, and I'll only have six. If I want to try making them from drill rod, I'll have to buy some rod (I only have one suitable size in stock), and I'm not sure how I'd make good handles.

I'm just thinking that making my own might cost a similar amount to the Brownells set, even though it is expensive.

Many thanks for the advice.

Chris

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Well ... it could be under or above -- just as long as it defines the extension of the drill rod while you are grinding it.

It depends on what you are doing. If you are doing a lot of drilling with a hand-held drill through things where there is something behind it which could be damaged, then a drill stop is important.

But -- you can *make* your own you know. Drill through the end of some round stock the size of the bit, turn the end smooth, drill into the side and tap for a setscrew to hold it onto the drill bit. No need to buy them in a bunch of sizes which you may never use. (I'm assuming that you have a lathe -- though you could do all of this with a drill press and a file if you had to.

Isn't there a quill stop? for the ones which have a scale around the feed, there is usually a wing-topped setscrew to allow you to clamp it to the the feed shank and limit the travel of the quill.

Better is when there is a vertical threaded shaft connected to the quill with an adjustable depth stop there.

Of course -- for certain things, there are much better tools available. For countersinks, there is the Micro-Stop, which can be adjusted for depth in steps of 0.001". These are commonly used in aircraft production -- for riveted joints with flat-head rivets, but can also be used with countersunk screws, or even to put a very shallow bevel on a drilled hole. The micro-stop has a thrust bearing to firmly stop the drill or countersink and a cage which contacts the work surface. One of these is nice to have -- just in general. Find used ones on eBay, don't play new price games with them. :-)

Good Luck, DoN.

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When you use both words in the same description, it is logical to assume that they mean different dimensions.

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Not too likely. since you should not get the tip at an angle which makes that likely. And it is more likely to be driven down than towards your chest, given the presence of the guard at the top.

But that is why I suggested putting a good handle on it first so it is too blunt to penetrate your body.

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Therefore tough enough to be a good screwdriver.

Yes -- with the caveat that all that I have have the tip width and exposed blade length specified in metric units, which may mean that they are not a perfect fit for an old imperial screw. I note that the two in my belt pouch ("Wiha", not "Wera") don't specify the blade thickness. The

2.5x50 (width & length) measures at 0.59mm (probably target of 0.60mm), or about 0.021".

The older (and larger) ones were made in Germany by Belzer, and are respectively: (thickness x width x exposed shank length)

1.0x6x100 0.6x4.5x100 [ ... ]

You have a lathe? You have a knurling tool? Turn a handle from aluminum or brass, knurl it for a good grip, drill to fit the shank, drill for a setscrew, and mill (or file) a flat on the shank for the setscrew to bear upon. Do this *before* you grind the tip, so you have something to blunt the shank if it does happen to dig in -- though it shouldn't as long as you are holding the tip tangent to the wheel. And you really don't want to be pressing hard enough to encourage a dig-in even at a wrong angle. Keep the pressure light, so you don't overheat the workpiece.

It would be a good set to have -- but you really should be able to make your own, too. I made my first one back in about 1977 I think, using a Unimat SL-1000 for the grinding, and an old worn-out Atlas/Craftsman 6x18" lathe for the turning and knurling.

I used a fairly small mounted stone to keep the tip length short before it got thicker and stronger.

Good Luck, DoN.

I'd make my own. In fact, we all did that in high school shop. Forged some drill rod, filed to shape, hardened, tempered.

You could probably get 3/16 drill rod up to red heat with a larger propane torch, give it a few good whacks, then do the rest by filing.

Sure you could file it with no forging, but in theory forging will be stronger. Shouldn't take more than a few minutes to file it.

Then harden. And temper, so it doesn't shatter. And even then you might want safety glasses when using it.

I have trouble getting my father's lathe to drill a piece of work centrally. The tailstock can be moved from side to side using set screws, but not up and down. It seems to be out in the vertical direction. I think the problem is that there's a cap screw under the tailstock which is unoriginal and has a head which protrudes slightly, causing the tailstock to sit at the wrong level. But as it's my father's lathe I have been reluctant to try fixing it. I use

No there isn't. There's just a scale. It's a cheap drill press.

Sounds like a neat tool.

Best wishes,

Chris

I had a look at the grinder yesterday. I think it would be possible to get a screwdriver bit into the right position, and that it probably wouldn't stick in the wheel. But then I had a look for a screwdriver of the right size to grind, and could only find my light-up electrical screwdriver. I didn't want to modify that, so I'll have to wait until I'm in a tool shop to buy a suitable screwdriver.

I think perhaps part of my reluctance is because I'm a bit of a perfectionist. I like good, accurate tools and I'm not sure that I can make a screwdriver of that standard. Good screwdrivers are really nice to use. The way they snugly fit screw heads is satisfying.

Wera and Wiha are different brands. Wera screwdrivers have a distinctive multicoloured handle with the dimensions of the tip printed on it. I've been very impressed with them.

The Wera screwdrivers also have a hexagonal shaft. It occurred to me yesterday that this could be helpful when trying to modify one, as it would help to ensure that the two ground faces are parallel.

I've got access to my father's lathe, but not a knurling tool.

I think the Brownells set is likely out of the question because of their ludicrous shipping charges. I am going to call a few horological suppliers on Monday see if they know of a source. Surely someone must make suitable screwdrivers?

If I don't have any success, I will have to make one and see how neat it turns out.

Many thanks,

Chris

Somebody else (most likely several) mentioned it already, but try using small hex keys (Allen wrenches). They are relatively inexpensive, hard and tough. If you grind/cut the

90 degree turn out of them a nice Pin Vice will hold them as a handle. Being hex shaped they shouldn't slip in the Pin Vice.

Don't worry about perfection, make something that will work and get the job done. That will be satisfying enough :)

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Hmm ... I wonder whether that was an attempt to adjust for a tailstock which was too low? Ask him about it, including whether you, or the two of you together, can try to fix that problem. Why not take the screw out, determine the threads, get a spare of the same size, and turn off enough head length to prevent the contact. (This way, you can go back to the original screw if you need to.)

And if it then too *low* -- the proper fix is shim stock of the appropriate thickness between the base and the top casting which moves sideways. Same thickness shim stock both sides of the screw so the barrel remains level.

Hmm ... does the scale (or the pointer) rotate as you feed the quill? Mine was a cheap drill press back in about 1976 or so when I got it new. Taiwan made, floor standing, 16 speeds. Check for a hole in the part which contains the pointer or the scale. If you find one, check whether there is a setscrew in there -- perhaps installed to keep the scale constant. Remove this, replace it with a longer screw, and you could have an adjustable stop in that rotating collar.

As for drill stops -- you can make them simply by taking tubing of a reasonable diameter, turning to the right length, and then slipping it on over the drill bit until it touches the chuck jaws. You may have to hold it in place -- or stuff it with cotton or blu-tack to keep it from slipping down onto the workpiece.

Enjoy, DoN.

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I would really not want to modify a good screwdriver -- I would prefer to start from scratch. A cheap screwdriver I would (and have) modified -- for example when I needed a split blade to drive a nut which had a slot on either side of the screw -- but needed a gap in the blade for the screw to project into. (Hex head on the screw, so the nut

*must* rotate, and the nut fit into a recess in a connector.) So I just grabbed a cheap screwdriver (Stubby one of the kind provided in Army toolkits, since I was working for an Army R&D lab at the time, and this was truly a government project, so I could expend a screwdriver for the cause. I simply took a file to cut the needed notch.

Perhaps what you need to do is to get a screwdriver with interchangeable tips (here they have 1/4" hex shanks and a corresponding socket in the handle), where you can buy a large number of hex screwdriver bits of many sizes and styles, and simply grind the bit to fit a particular screw -- mark it, and keep it for the next time you need that size. Replacement bits are inexpensive, are good tool steel for the purpose, and it should be easy to make a fixture to hold the

1/4" hex shank while grinding it.

Good screwdrivers with replaceable bits sounds the way to go, then.

But a cheap screwdriver which has been reground to fit the screw in question is better than a perfect screwdriver with is either too thick or too thin.

That sounds like a description of the Wiha ones in my belt pouch. Handles are black with a red cap which pivots to allow you to hold it pressed into the screw slot with a single fingertip. The width and thickness are printed on the black part of the handle.

Hmm ... I've seen some screwdrivers (SnapOn among them) which have a hex forged just below the handle for allowing wrench to assist with a really tight screw. (And yes, the screwdriver was forged tough enough to handle that kind of abuse.)

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Then consider getting a knurling tool for it. Ideally a scissors style knurling tool, so you don't overstress the machine.

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Changeable tip screwdrivers, with lots of spare tips so you can grind them to fit different screws.

Good Luck, DoN.

When I have a soft, cheap one that I want to keep for some reason, I polish off any plating near the tip and give it two or three passes in case-hardening compound. This is one situation where you *do* want to temper after case-hardening, but I just do it with a torch, and temper by color.

-- Ed Huntress