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I have a chipwood panel. I need to drill holes into it at specific locations. A small error is acceptable which means that I do not need to use a CNC machine for this.

Here is a diagram that shows something similar to what I will eventually be doing.

enter image description here

Questions:

  1. What tool do I need to use to measure and mark the exact locations? Using measuring tape is not proving easy. I can't use vernier calipre here too.

  2. Also, right now once I know location of the hole, I put a + screw driver on it and hit it with hammer. This helps to drill hole in that location later. Is there a better tool or method to mark drill hole location?

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    "A small error is acceptable" - what do you mean by "small" exactly? "Using measuring tape is not proving useful" - what is the issue with it? Commented Jan 28, 2023 at 13:09
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    Is it acceptable to oversize your hole by a tiny bit (say, 1/32 or even 1/16”)? If so, go back to the measuring tape and square — they’ll be acceptable. And using a 3” screw as a punch to mark the hole will be vastly better than a screwdriver. Commented Jan 28, 2023 at 14:26
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    You can use an awl to create the drill point starts (or even a nail)
    – Ashlar
    Commented Jan 28, 2023 at 15:34
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    I thought I addressed this in a previous Answer or Comment. Don't the hole positions not actually matter? They just need to be approximately in the corners so no measurement of any kind is needed; you could just eyeball this. The only thing that really matters is the matching holes in the other board, which is simple: mark through the holes you've already drilled. But if you do want them even for OCD reasons (just because) you can make one or two marking guides from small bits of card. Punch holes in them with a nail or screw, then align the edges and mark your holes through the holes. Done.
    – Graphus
    Commented Jan 28, 2023 at 16:52
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    If you ever figure out how to get to nm precision, TSMC would like to offer you a job in semiconductor production. There is a multi-billion (trillion?) dollar industry just centered around the problem of getting things to align on that level of precision ;)
    – Max
    Commented Feb 16, 2023 at 14:34

4 Answers 4

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High accuracy isn't needed here, so I think just eyeballing the hole positions could be perfectly fine.

A step up from this would be to 'finger gauge':

Finger gauging

If you do really want consistency then a simple marking guide made from card would work well:

Card Guide 1

Align the edges to the workpiece, mark through the hole, rinse and repeat.

For a step up, I present the 'deluxe' model, with Auto Edge Align™:

Card Guide 2

Even made from card a guide like this can survive in a workshop environment for a surprising amount of time, easily lasting through multiple projects that have the same marking requirements.

This is similar in principle to some drilling guides which are used to mark fixed hole locations for dowels, shelf pins etc. on repeat projects. Sometimes these are made from thin sheet metal, but more typically hardboard or thin ply/MDF is used in a woodworking context.

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  • Card guides can also be made by printing onto card - printers are really quite accurate these days. printing onto paper and sticking onto card also works, using glue sticks to avoid wetting and stretching the paper.
    – Chris H
    Commented Jan 31, 2023 at 16:04
  • @ChrisH, yes, and some printers can print directly on to card stock of the weight I used. But regardless this is a level of accuracy that is completely not needed here. As far as we're aware, the positions of the bolt holes for this project can be completely arbitrary.
    – Graphus
    Commented Feb 1, 2023 at 7:45
  • True. But if I wanted to screw at an arbitrary location in each corner, I'd want to measure enough that it looked even - i.e. the same arbitrary number for both offsets of all 4 corners. Of course I'd just use a square and a pencil for this job, but a card guide would do the job nicely
    – Chris H
    Commented Feb 1, 2023 at 9:01
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Tape measures are usually used by carpenters where 1/8" or 1/16" is more than accurate enough. Woodworkers often use precision rulers to get accuracy of 1/32" or 1/64" inch when needed but will frequently use a simple tape measure because 1/16" is more than accurate enough. If that's still not accurate enough for you, you can purchase a machinist's rule that will give you accuracy to a couple of mil (1 mil = 1/1000")[1].

To use the tape measure, you simply hook the end over the thing to be measured, pull until you get a few inches past the desired distance, make sure they tape is square to the edge (eyeball it is fine), then mark at the distance desired.[2]

If you need to measure 3" in from each edge to make a center point, measure 3" from one edge and use a square [3] to draw a line parallel to the edge you just measured from. Along that line, measure 3" from the perpendicular edge and make a mark. You now have a crosshair at 3" from each edge.

Now that you have a pencil mark at your desired drill location, it's recommended to use an awl, a nail, a screw, or other fine, pointed device to make a starting hole for your drill bit so that it goes right where you want it and doesn't wander off. You align the point where you want the hole and push until you've got a bit of a dimple. You then put the drill bit into the dimple and (slowly) start drilling until you've got your hole started, then you can speed up.

Personally, I've used one of a couple of different size awls over the years. I just recently got a spring loaded punch that works even better. I set the point of the punch where I want it and start pushing. Normally, that's all there is to it. With the spring loaded punch, when I push hard enough, the spring fires and an internal hammer hits the punch making a much deeper mark with far less effort than trying to do it by hand. Making a good mark in pine isn't difficult, making one in oak or maple is far more difficult.

To accurately drill through your two pieces of material and get your holes to line up, you can clamp them together so that one mark will get you through both pieces of material at the same time. If you don't want to do that, you can drill through one piece, then lay that one on the other piece and either put the bit directly into the existing hole and drill through from there, or using a fine point pencil or pen, mark the hole location onto the other piece and separately drill the other hole.

I believe you'll get the most accuracy by clamping the pieces and drilling both holes in one pass of the drill. If you should happen to not drill at exactly 90° to the surface of the first piece, you hole in the second piece will still be precisely lined up with the hole in the first and at the same angle. Either of the 2-step drilling processes can leave the holes at slightly different angles and, if you're drilling with tight tolerances, could make it difficult to get your hardware through the hole.


[1]Good luck trying to work with wood to that accuracy, but you're certainly welcome to give it a shot if you want. Wood is a natural product with a more-or-less random grain that is going to cause your measurement to the mil to end up wandering off. You can work metals to those kinds of tolerances, and you car's engine is thankful for it.

[2] You'll notice that the tab at the end of a tape measure is loose. It's that way on purpose. The looseness precisely correlates to the thickness of the tab. You hook it over the edge of something and pull and get an accurate measurement from the inside of the tab. You push the tab against the inside of something and get an accurate measurement from the outside of the tab.

[3]A Speed Square™, a tri-square, a framing square, a combination square - it doesn't really matter, they'll all work and they all have advantages & drawbacks.

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    If you;re thinking about buying tools, a metal metre rule with mm markings is a very useful tool (at least for those of us who work in metric). Mine is used for woodworking, sewing, general craft with my daughter, and many other things, and its ends can be used to give a right angle with acceptable precision. My try square is also marked in mm on all edges of the blade.
    – Chris H
    Commented Jan 31, 2023 at 15:28
  • ... so here I'd use the square and (if necessary) the rule to mark the top piece, then drill pilot holes through both.
    – Chris H
    Commented Jan 31, 2023 at 15:29
  • @ChrisH I have (at least) a dozen different tools with which I could easily measure and mark holes at the edges of the boards as our OP is asking to do. He's a very new DIY/woodworker (based on other questions), and has a very limited selection of tools, so I was attempting to describe a process with a very limited number of tools.
    – FreeMan
    Commented Jan 31, 2023 at 15:52
  • I basically agree, but these (especially the rule) are very basic and versatile tools. Mine was about £10 or $15 (US), and unusually for me was UK-bought (I used to buy measuring tools on holiday in France because theirs don't waste space on inches)
    – Chris H
    Commented Jan 31, 2023 at 15:59
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    Waste space on inches? What are you talking about??? It takes 2.54 of your "centimeters" where I only need one single, solitary inch!!!! :D
    – FreeMan
    Commented Jan 31, 2023 at 16:04
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I'd like to provide an alternative answer that doesn't require tooling:

Create construction lines with a measuring tape

The problem is not that the tool is not accurate, but technique is not correct. You mention in the comments that you can "only measure one axis at a time", but you can create construction lines by doing so.

  1. Measure in 3 inches in both axes from each corner. Eyeball it as square to the edge as possible, but within a couple of degrees is fine.
  2. Using a straightedge, join these marks together to draw an entire rectangle around the entire board (you don't actually have to draw in all locations, just near the corners)
  3. The intersection of these lines is where your holes will go for the corners.

Technique is very similar for the long row of holes:

  1. Measure in 8 inches on top and bottom of the board
  2. Draw a construction line vertically
  3. Measure along that construction line and mark the vertical distances of all the holes.

Your center punching technique with a screwdriver is good - you can actually use a "center punch" if you'd like to purchase the right tool for the job, but even the handiest of handymen lose theirs on the day they buy it and resort to using a screw, nail, or whatever else is around at the time.

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    Ah! Maybe I've still got my centre punch after at least three decades because I didn't buy it; I was given it by my Dad. Commented Jan 31, 2023 at 8:31
  • I do have a centre punch, but for wood I prefer a 6" nail that I've ground to a sharp point (or a scratch awl of course)
    – Chris H
    Commented Jan 31, 2023 at 16:06
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This sort of thing is exactly what a marking gauge is for. You set the gauge to some desired dimension, say 3 mm, and then scribe a short line parallel to the edge of the part in the vicinity of the hole's center. Do the same from the adjacent edge, and the point where the two lines intersect is the center of the hole.

If you don't have a marking gauge, you can use a combination square the same way. Set the square so that e.g. 3 mm of the rule protrudes from the head, and then use a sharp pencil to mark a line that distance from the edge. Repeat from the adjacent edge.

If you don't have a marking gauge or a combination square, you can use setup bars, drill bits, blocks of wood that you cut on your table saw, or any other objects that happen to have (or add up to) the right dimension. Put the part on your drill press such that the corner of the workpiece is exactly at the center of the bit. Clamp the part in place. Place a 3 mm setup bar (or other object that's 3 mm wide) against the edge, and then place a block of wood against the bar, and clamp it in place. Repeat from the adjacent edge. Now remove the bar, unclamp the part, reposition so that the part is against the two blocks, and drill.


Since you've already got a diagram, one of the easiest ways to locate all the holes at once is to print your diagram out at full size. Spray the back lightly with spray adhesive, e.g. 3M Super 77 Multipurpose Spray Adhesive and then stick it to your workpiece. Thin double-stick tape can also work, but the spray is nice because it secures everything well, but is still easy to remove when you're done. Drill your holes right through the paper in the marked locations.

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  • OP has a calipers, which (although frowned upon by purists) can be used quite effectively as a scratch gauge.
    – Graphus
    Commented Jan 30, 2023 at 18:31

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