[Derek] was using his Dremel drill press to prep a bunch of PCBs, and found that it was getting difficult to focus on the spinning drill bit each time to line it up with the solder pads on the boards. He figured that a laser sight would help move the process along, but since no off the shelf solution was available for his press, he built one of his own.
He bought a cheap desk lamp with a flexible metal neck, which he disassembled, saving the flexible metal sheath. He installed a conduit clamp on one end of the neck, and a laser module at the other. [Derek] then mounted the laser arm on the press’ crow’s nest aiming it at the tip of the drill bit.
As you can see in the video below, the ability to easily position the drill bit using the laser helps him make quick work of any PCB.
[youtube=http://www.youtube.com/watch?v=DFXv9WlAM8Y&feature=player_embedded&w=470]
It seems that using two laser modules with line-lenses so that you have a cross projected on the target would help with making sure that you’re always lined up no matter what height the drill target is.
the laser does not move along with the dremel…
@samuel: A laser projects a line, which we view as a point when it hits a surface. If a lens turns the beam into a plane, we view it as a line on a surface. If the dremel also moves along that plane, it will always line up. Two lasers, rigidly mounted to the platform, projecting a line down the drill axis would be in line with whatever else was on that drill axis, regardless of its height or the bit’s height.
1) Drill one hole.
2) Without sliding the PCB, adjust laser to point directly at the drilled hole.
3) Drill rest of holes using the laser guide. The drill target height will not suddenly change in the middle of a flat PCB…
Another vote for two crossed line-generating lasers. Not only is this more elegant and should require zero adjustment between material thickness and bit length, but a concentrated laser dot is not usually fun to stare at for long durations.
Yeah, we had this conversation a few months ago when someone stuck a crosshair laser (not two line lasers crossing over as you say) on, well, their laser.
Same problem then as now, the laser aiming dot moves sideways as you move up and down (z-axis).
I suppose if you’ve a short-term memory then everything is a new hack (or you re-invent the wheel poorly).
The board top surface is at known height, so he just aims the laser at the point where the drill will hit tat surface. You only need to adjust the laser once, and then move the board around so the laser spot hits the vias to be drilled, and lower the spindle.
His spindle movement is interesting–looks as if it was automated, not manual (slow move followed by quick peck).
I think you’ll find the quick increase in downward speed or ‘peck’ is when the drill exits the hole and is now not hindered in movement by the PCB material, and is free to move much easier considering the higher pressure still applied to it by the operator from when he was drilling the PCB.
PS: For anyone complaining about the Dremel stand being useless, buy a Proxxon.
awful idea, flexible neck moves without you noticing and then the hole is no longer on center.
mount it properly so its fixed
People seem to preffer flexible necks for some reason. Maybe it’s to compensate for different drill lengths and sizes? If you fix it you’ll have no possibility of changing it afterwards.
Also your comment is awful 🙂
It appears to work just fine. Some of those flexible necks are very stiff. A sliding mount on a solidly-mounted shaft would also work, but I don’t think it’s anything to get upset about.
A lower-tech fix I have used to make the drill bit a bit easier to see is just to rub a black sharpie onto the bit, getting the black into the groves too. The blackened bit is easier to see.
the details may need a little work but the concept is brilliant!
Yeah, but bad for the eyes. When you get cataracts, remember this thing. Or use LASER safety glasses.
Cataracts from pure 635nm light? If you’re really that worried, I have some tinfoil contacts for you.
Sure lasers are fricken COOL….
But etching a small hole in the centre of the pad causes the drill to self-centre.
this a ridiculous, how could you possibly trust that the laser is properly aligned when it’s mounted on a movable goose neck ??? not to mention the dremel press that it’s mounted to is a complete piece of shit (yes i own one) there’s so much play and wobble in the plunging action that it’s unusable for anything but rough work.
actually, come to think of it, all this thing needs is an arduino and some blue leds and it’ll be a hackaday top 5 post of all time.
Sorry? How does a laser force-center the drill bit onto a job, and how can you center on the middle of the pad with a beam that is likely as wide as the pad itself?
Either shine a bright light across your job to illuminate your work, or, as Cyril said, etch out the center of the pad (much like centerpunching a piece of stock for drilling) and get perfect holes every time, without needing to tack crap onto your tools
MOST thing are better with lasers, not all.
So what if the laser dot is as wide as the pad itself? Just cover the entire pad, and you know the hole will be centered.
Force centering? Not a good idea with any of the smaller carbide bits. You may get away with it 500 times, then snap a bit that could have lasted much longer.
Part of the point of hacks like this is that I would never have tried it because I would have assumed that it just wouldn’t work, it obviously does work and I might try this next time I see a cheap laser pointer lying around.
Many of the simpler hacks on hackaday are worthy not becuase they’re technically brilliant but because they employ methods that one’s intuition would tell you aren’t going to work, and seeing them wor helps you to refine that hacking intuition.
I would love to see a hack to stiffen up the dremel press and make it more accurate. I love the size and cost of mine, but as others pointed out, it is useless for drilling PCBs.
I would recommend a jewelers drill press for PCB work. But with dremel, parts are abundantly available and the rotary head can be used for other purposes.
Thanks for that comment! I had always thought my dremel press was simply defective all these years. Have tried to tighten the thing up to no avail. It is truly useless for anything requiring precision.
I’ve got a $60 full-sized drill press from Harbor Freight. Incredibly loose, probably worse than a Dremel. The first few attempts to drill PCBs ended in a lot of broken bits and unusable holes.
But I found a solution. I tied some twine around a non-rotating part of the spindle assembly. Ran that over another part of the press, and tied the other end to a 5lb. weight, which hangs suspended. The result is that the spindle is preloaded backwards (away from me) with 5lbs. of force, which exceeds any force generated by drilling. It ain’t pretty or elegant, but now my holes come out perfect, and no more broken bits. Perhaps something similar would work for the Dremel?
I can add a few points to the discussion given my experience with this setup:
1) I’ve used it for a few years, so it does work. With a hand drill I used to do <100 holes before breaking a carbide bit, now it's easy to do a few thousand and they're better aligned
2) There is a laser cross module available if you prefer to see an X instead of a dot (see references on page)
3) The flexible neck doesn't move unless you bump it, and it's mounted to the stationary pole so it doesn't move with the bit (i.e. points at the same spot). A fixed mount doesn't allow you to change the thickness of your workpiece and will likely be more out of alignment (since a cheap drill press lacks rigidity)
4) It's fairly easy to align this system by turning off the drill and bumping the tip against your workpiece. Simply line up the bit with a hole and move the laser to the same hole to get started. I usually spend less than a minute lining it up before a marathon drilling session
5) The dot can be quite small if focused correctly (it fits inside a standard PCB hole as shown in one of the images). It's important to have a module that you can focus or the spot diameter will be too big
6) It's also important to dim the laser significantly, at full brightness you can't see anything. The variable voltage supply attached to the laser allows you to dim it to almost nothing (easy to look at for hours on end)
7) This project is about visualizing where the drill bit will hit the workpiece (it's not meant to align anything). Even if your holes are etched (which mine were) you still need to line up the hole and the drill bit. When I did this pre-laser it was hard on the eyes because you can't focus on a moving drill bit to line up every hole
8) A Dremel drill press isn't great quality but it certainly works to drill through flimsy pcb material. This solution isn't specific to the Dremel press so it could be mounted on a better drill press if you have one. But the high speed Dremel tools are great for working with carbide bits, hence the Dremel drill press
This is a nice hack. Though I’ve found a much more accurate way of doing this. I use an old web cam underneath the drill press facing up through the hole in the plate that holds the PCB. I then put a cross in the webcam image (some webcam software allows for this, or you can just use your mouse pointer). With this setup, you can zoom in to get a nice big image of the drill target and get a perfectly placed hole every time.
Don’t the shavings from drilling fall onto the webcam lens?
Wouldn’t you have problems with drilled out material falling down on top of the camera lens? When I use a light underneath the board it usually gets covered up with dirt by the end of drilling
Also you would only see the bottom of the board, not where the drill bit was going to hit?
The problem I see is that laser pointers have a radius R1 and the bit has radius R2.
This works if R2 > R1, but when R1 < R2 you can't be sure you are centered. The crosshair solution has the same problem as you get a square at the center that could be larger than the bit. I have not seen a good laser for less than a few hundred that doesn't have a fairly large dot. By Large I mean a few mm. If you know of a cheap sub $20USD pointer with a dot diameter < 2mm @ 12 inches please post it.
That should read “R2 > R1, but when R1 > R2”
You should take a look at the laser module that I used in this project:
http://dx.com/red-laser-module-focusable-dot-3-5v-4-5v-16mm-5mw-5914
I don’t have any problems centering the laser inside a hole. The fact that it’s focusable and dimmable (with a variable voltage supply) makes the resulting dot very small. It’s definitely less than 2mm diameter although the distance isn’t 12 inches. The focusing should handle the change in distance
For PCB’s a laser shining from the bottom might work too, seeing most PCB’s are somewhat translucent.
For the rest I agree with the remarks made by others about projecting 2 lines, this setup with a flexible arm is just a bit too fiddly and needs constant adjustment.
too cool! What a great idea. It WILL be on the shelfs soon. Did you patent it yet?