# Drilling tiny holes



## Bustedbricks (Jul 30, 2012)

I need gas jets in quantity but have not had any luck finding a wholesale source. Making them myself is an option but drilling a 0.2mm hole is an obstacle. For low volume I can turn down to a thin wall and pierce with a sewing needle. It does the job but is a bit hit and miss, not to mention time consuming. Anyone have any suggestions how to go about making a lot of 0.2mm holes in brass in an efficient way?


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## Herbiev (Jul 30, 2012)

Busted bricks. Just a thought but have you thought of making a cheap basic EDM. and using 0.2mm wire. Lots of simple EDM designs floating around


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## Bustedbricks (Jul 30, 2012)

I have thought of EDM but I'm not sure I can get the precision needed. Then of course there is the issue of cost to build the EDM.


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## Bluecat (Jul 30, 2012)

Here's how I would approach the problem.
You want to make several identical pieces. Therefore, the only way to go (besides EDM) is to make a suitable drill bit. I'd have a go of tinkering around with a hard abrasive stone and some fine needles (or possibly string wire) until I got a working tool bit. I'd then turn a shank for it and to avoid heat damaging, instead of brazing use a grub screw to fix the bit in place. So I'd have a 0.2mm bit with a, let's say, 4mm shank.
Just my two cents worth. Bear in mind though, I've no experience in this. Also, I don't know whether this would suit your accuracy needs. I suggest you look at watchmakers' drill bits, those could be of help to you perhaps.


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## Dan Rowe (Jul 30, 2012)

I did a srarch for "micro drill" this was on the first page.

http://www.bigkaiser.com/micro-drills.php

Dan


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## kvom (Jul 30, 2012)

How about using a fine screen rather than a plate with holes.  EDM is slow, and you need a hole already to thread the wire.  Perhaps a row of the needles held in an array and used as a punch.


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## Bustedbricks (Jul 30, 2012)

kvom said:


> How about using a fine screen rather than a plate with holes.  EDM is slow, and you need a hole already to thread the wire.  Perhaps a row of the needles held in an array and used as a punch.



A gas jet has just one hole. I think you are thinking of the burner. Those I make with ceramic material.


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## Bustedbricks (Jul 30, 2012)

Getting drills is not a problem. Not breaking them is. They are extremely fragile at this size.


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## Gedeon Spilett (Jul 30, 2012)

for such a small size you need a perfect concentricityin your lathe setup, a good light, and a magnifier.
I did it exactly for the same aim, butane burner jets, so it's possible.

0.2 mm drills can be found in the trade but pretty expensive and do not expect to drill more than a length of 0.5 mm. 0.3 mm are easy to find, much cheaper, and can be reduced as follows.

the drill must not be hold directly in the drill chuck or collet but in a home made collet : a small piece of brass is turned to 3 mm dia for a max of  15 mm, then drilled concentrically half-way 1.5 mm dia then 1 mm for half of the remaining length and drilled through with the 0.3 mm drill, and finally cut. This is your collet, you may either slit it longitudinally or simply use loctite to hold the drill. insert the drill in the collet leaving only a minute amount of it, no more than 1.0 mm. 
You can use it as such or with your dremel and a small grinding wheel (dressed with a diamond stone) in a toolholder you can carefully reduce the drill diameter to suit your need. 

*Drill break occurs when the workpiece is not dead flat or the drill is not properly centered on the workpiece, so do not use a center drill, but make one : a small sharp coned D-bit will do it. *
when your are at it with the dremel on the tool post, try to make your own tiny flat drill with the tail of a broken drill or 2.3 mm dental burr : grind a cone about 90°, then reduce the dia to the wanted size for a 1 mm length, and with the lathe stopped the awkward part is to mill 2 flats 180° leaving some thickness between. these drills work very well, but are very fragile, and break easily on storage.


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## Don1966 (Jul 30, 2012)

Why not go to time savers and order a clock jewel pivot for you orfice. They make plenty of different sizes.

Just my 2C Don


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## Bustedbricks (Jul 30, 2012)

Don1966 said:


> Why not go to time savers and order a clock jewel pivot for you orfice. They make plenty of different sizes.
> 
> Just my 2C Don



Time savers? Don't think we have those in the UK.


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## Bustedbricks (Jul 30, 2012)

Zephyrin, many thanks for the tips. I may give that a try but a friend has offered to help me make an EDM machine. It may be possible to make it work without a feedback loop. It would use a simple "2 steps forward, 1 step back" code to drive a stepper. I have all the parts needed for that.


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## Dan Rowe (Jul 30, 2012)

Bustedbricks said:


> Anyone have any suggestions how to go about making a lot of 0.2mm holes in brass in an efficient way?



The smallest drill I have is a #80 which is a tad larger than what you are drilling.

I used a 1/16" carbide spot drill and a cheep #80 drill to drill K & S square brass tube which is .014" wall I believe. I had no problem using my micro drill press which is a Servo.

http://servoproductsco.com/html/servo_drill_presses.html

It is rated for .1mm drills and I think that I would have no trouble with that size drill.

Dan


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## keith5700 (Jul 30, 2012)

Busted, I would get a pack of 10 solid carbide circuit board drills and just have a go with them before doing anything exotic.
I bought 10 x 0.25mm drills for a fuel injector and these went straight thro silver steel plate to about 2.5m depth, and that was only about 1000 rpm. Deeper than that was a problem though.

I then used them in the miller to go through some copper tube for some oil spray pipes, and they blasted through that easily.

They have a 1/8" shank so are easy to hold, and I think they were about £12 for 10 off ebay. I thought they were going to be really rough for the price but under the microscope they look absolutely spot on.

I don't know how deep you want to drill but a couple of mm should be do-able.
Take your time with the feed and, as someone said earlier, get some magnification on the job.


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## Bustedbricks (Jul 30, 2012)

I'll give the drills a try. I only need to go through about 0.5mm brass. If that does not work I might try and make jets with a drilled disc insert. I have some 0.1 sheet and would drill the hole then punch out a disc.


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