5
\$\begingroup\$

I use a drill press like the first one in the linked answer at home for drilling my PCBs. If there was a way of sliding a PCB along a straight line left-to-right (or front-to-back) it would make drilling holes which are in a straight line much faster.

Do such slider systems exist without big costs? Or is there a design someone can share for making one? If there could be a system which also has ratchet-type stops every 0.1 inch, and which is equipped with a "latch" to switch between left-right and forward-back, that would really help.

\$\endgroup\$
3
\$\begingroup\$

A cross-slide will work for you as well. I have one on my christmas list. :-)

|improve this answer|||||
\$\endgroup\$
  • \$\begingroup\$ Oh awesome! Why did I not know such a device existed? Just found a local store selling these for around $20, picking mine up later today! Thank you, thank you! \$\endgroup\$ – ExcitingProjects Nov 30 '12 at 10:48
3
\$\begingroup\$

Look at the extrusion 3D printers for cheap linear shafting ideas, using either rollerblade bearings at right angles, sleeve bushings or even sleeve bearings.

However, you will then encounter a problem familiar to users of real machine tools, which is the need to align the row with the machine axis.

By the time you go for ratcheting you may just want an X-Y table, though exercise some care to get inch or metric screws with a lead-per-turn closely related to your spacing. If you don't do that, you'll likely want to add a digital readout or even servo/stepper drive. And then you need to learn about managing backlash.

There's a reason machine tools are expensive...

|improve this answer|||||
\$\endgroup\$
  • \$\begingroup\$ do you feel 2.5 mm pitch lead screw is close enough to 2.54 as long as I check each hole position carefully before drilling, or will that add too much variation over a typical 4 inch PCB length? I'm going to go google for small and light XYtables. \$\endgroup\$ – ExcitingProjects Nov 29 '12 at 16:08
  • \$\begingroup\$ No, it is not close enough. After an inch of travel you would be off by 16 mills, or half the diameter of a typical real PCB hole. After 2 inches you would be off by half the diameter of a 1/16" drill bit, which is pretty course even for a homemade PCB. \$\endgroup\$ – Chris Stratton Nov 29 '12 at 16:32
  • \$\begingroup\$ One thing that may help you get good results is to design your pads with a small hole in the center. This can help guide the drillbit when freehanding the positioning. \$\endgroup\$ – Chris Stratton Nov 29 '12 at 16:33
1
\$\begingroup\$

The first part of what you ask for is just called a "fence", and it can be as simple as a bit of wood with two slots in it. Use wingnuts or some other quick release clamps so you can move it to a new row position easily.

|improve this answer|||||
\$\endgroup\$
  • \$\begingroup\$ That's what I do now! Just without knowing the name "fence"! \$\endgroup\$ – ExcitingProjects Nov 29 '12 at 16:04
1
\$\begingroup\$

Late but I think still relevant. Centre punch the board by hand. Once the pads are (lightly) centre punched, the drill bit will find it's own position. Just use some delicacy and stay away from lump hammers or you'll crack the board. I find my go to hammer is a tack hammer, used surprisingly enough for knocking in tacks.

You could use a guide /fence, but if you have several packages to drill lines for, you'll spend for ever trying to line the thing up properly. Then there's all the clamping and bolting to the drill press. Heavy or very accurate drilling would be done on a x/y table or cross slide. They're expensive and you're back to all the lining up and clamping issues again. Unless you're press fitting a mechanical component into the pcb, you don't need more accuracy than what, 0.25mm? Very few components have absolutely rigid pins so they will tolerate some slack in the hole placement. You should easily achieve the required accuracy by hand.

|improve this answer|||||
\$\endgroup\$
  • \$\begingroup\$ Having a start hole is an aid to drilling, but it's even better to etch them than to punch them - especially on phenolic stock which is generally easy to work with but would easily spall if centerpunched. Especially if the drilling machine itself is cheap (ie, has runout) this self-positioning (with a wire drill) may work better than trying to pre-position the drill exactly and see it wander or cut oversize. \$\endgroup\$ – Chris Stratton Oct 21 '16 at 0:38

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.