Suitable replacement for a Jig Borer?

[DeanDK]

Hello,

I'm from Australia, where quality used machines aren't easy to come by, and jig borer's that can fit in my man-cave are even harder to come by.

I need to drill small holes ط0.5mm - ط2.0mm in brass in very precise locations.

I had a thought (I have my flame suit on).

Would say using a Cameron Micro Drill Press (high speed, low runout spindle) with a high precision xy linear slide (Zaber brand) produce good results? The travel distance I would need would be 60mm in either direction.

Anyone care to provide insight why this would be a half decent/bad idea?

[darryl]

I don't know that drill press, but high precision spindle, quality xy slides- it seems the parameters that would be required are low runout, tight quill and smooth quill motion, zero play in the slides. If it can achieve that, I'd have to say you're good to go.

[oldtiffie]

You will need to see that the end of the drill bit does not "wander away" and thus create a positional error that may not be constant in all holes.

[BCRider]

So you would be fabricating your own jig borer. If it's done well I don't see why that would not work.

For small drills like that the usual machines often do not turn at the sort of speeds needed by that small a drill. So I think you have a decent enough plan. The success and usability will depend on your locating the drill head and supporting it accurately over top of the X-Y table.

If you're doing enough of this sort of work and you're making money off it I'd also think that fitting the X-Y table with a DRO would make your life much easier.

Old Tiffie may have a point and you may find you need to do one run with a spotting drill or make good size marks with something like an engraving bit for the drill bits to avoid wandering. Of course that means two passes over the work so consistency would be important. Or have you done this sort of work and found that just pecking with the drills was enough?

[DeanDK]

Thank you everyone for your replies.

Yes Oldtiffie has a good point about drill wander, I usually spot them with small centre drill, I usually do these holes in a watchmakers lathe. With the hole pattern stuck on a piece of brass, and use a centering microscope in the tailstock. This is a very tedious task.

Im planning on getting a motorised xy linear stage, fine pitch thread .. Sine each of my plates that I drill have a centre hole, I was thinking of drilling that hole first and then use that as an origin point to co ordinate the other holes from.

[boslab]

Titex make a good drill that if run at the right speed doesn't wander, it's a hell of a speed too!
Think 20k or more, a table with dro would help but if repetitive consistent plates needed a guide plate with drill bushes set at the right centres, I used one with a sliding table and the X and y were set with a pack of slip guages, you soon figured making packs with the least slips, unless you have 2 sets!
Mark

[MrSleepy]

No idea what your working on...

but I use my cnc router to drill accurate holes in pcbs in the 0.6->3mm range. I use Gerhard Burgers "Excellon to G-code" program to convert Easy-PCs drill plot,then run the G Code in Mach for drilling, before photo developing and etching.

If I needed to drill lots of precision holes on a brass sheet I'd just make a circuit board design with only pads , then cnc route it.

[Jaakko Fagerlund]

No idea what your working on...

but I use my cnc router to drill accurate holes in pcbs in the 0.6->3mm range. I use Gerhard Burgers "Excellon to G-code" program to convert Easy-PCs drill plot,then run the G Code in Mach for drilling, before photo developing and etching.

If I needed to drill lots of precision holes on a brass sheet I'd just make a circuit board design with only pads , then cnc route it.

That way gets you only maybe good enoug holes, but the locations are not exact as a CNC routers XY motions are not calibrated usually to anything.

[David Powell]

We have such an outfit.

Hello,

I'm from Australia, where quality used machines aren't easy to come by, and jig borer's that can fit in my man-cave are even harder to come by.

I need to drill small holes ط0.5mm - ط2.0mm in brass in very precise locations.

I had a thought (I have my flame suit on).

Would say using a Cameron Micro Drill Press (high speed, low runout spindle) with a high precision xy linear slide (Zaber brand) produce good results? The travel distance I would need would be 60mm in either direction.

Anyone care to provide insight why this would be a half decent/bad idea?

We have a Cameron drill press which is equipped with a small XY table, make unknown, Anodised Aluminium construction., about 50 mm travel each way . Judy uses it for precision miniature woodwork, using tiny burrs at full speed, it will produce neat clean slots or ornamental edges etc if needed( Imagine a chest of drawers about 2" tall.looking like real furniture and you have an idea of what she makes) Used as intended she can place holes #60 and less exactly where she wants them, but that is by sight not by precision measurement so far.If I were needing to drill holes EXACTLY where needed I would equip it with two dial gauges, one for each axis. ( Or just put the job on my Emco mill, but that only runs up to 2500 RPM or so). I hope this is encouraging David Powell.

[Mcgyver]

What's precision?

How many holes?

How many pieces?

[J Tiers]

So turn it into a jig borer. Put a plate at 90deg to the column, with a hole for bushings. Hardened bushing in the hole that fits the drill, and no issues with wander. Was done a hundred years ago, should still work now.

You can make and harden the bushings, care taken there pays off with the holes.

[garyhlucas]

Isn't the important word here 'borer'? Drilling is not considered a precision operation. If you need precision you ussually drill then bore. That gives precise location, diameter and roundness. So at the least you'd need a boring head to do it right.

[old mart]

You need stub drills of the minimum length to clear in the workpiece, and lots of speed. At these diameters, boring is not really on. Perhaps solid carbide would work because of the stiffness.

[oldtiffie]

First of all, there are varying grades of DRO each with its own accuracy - and that means that each and every hole will need to be approached from the same direction (X and Y) else you will or may get "bitten" by the "back-lash" due to the DRO accuracy limitations.

Check these (very good) "Easson" DRO's which have accuracies of 1um (micron) - for grinders - and 5um (micron) for "other" set-ups (lathes, mills etc).

Note that 1 um (micron) = 0.001mm = 0.000039 inches - note that 0.000039"is near enough to 0.00004"= 0.4 "tenth"

Easson scales (DRO) are here.

https://www.machineryhouse.com.au/Digital-Readouts-Easson

[Toolguy]

Note that 1 um (micron) = 0.001mm = 0.000039 inches - note that 0.000039"is near enough to 0.00004"= 0.4 "tenth"

That is 40 millionths. Less than half a tenth. I doubt if the average HSM would have any problems by missing the mark that much.