This is an adjustable light duty drill guide with a fence that can be used either to assist in alignment or as a dust collector. The "cylinder" rotates, and will index to set the drill guide sizes for any of the 6 holes.
This version has a "cylinder" which is designed with holes that are 2mm, 3.6mm, 4.4mm, 5.2mm, 6.0mm and 6.8mm (which correspond to 5/64, 9/64, 11/64, 13/64, 15/64 and 17/64 sizes).
In actual use I found that I needed to allow 1/64" extra so the parts I printed worked well with these sizes:
It is still possible that the holes may need to be drilled to their final dimension with the drill being used, since there is always the usual 3D printing surface roughness. On the one I printed the holes were correctly sized to the drill bits above. The "cylinder" is designed to be replaced if other sizes are needed, and the STEP files are included which should make this easy to remix or add different drill sizes.
The base and fence have marking lines spaced at 10mm intervals on the base and fence to help in alignment, as well as some sighting and marking holes which can be used to align the guide. Finally the fence can be locked into place which can help when making many evenly spaced holes (for making shelf support holes for example). M3x16mm screws are used to secure the fence to the base, and the Allen wrench can be stored in the fence. Finally, the fence can be flipped around and used as a dust catcher when drilling holes in vertical surfaces.
As simple as this thing is, it took me a good number of weeks to get it right. The dovetails alone were a bit or trial and error to get them sliding well enough, yet not being too loose. There were also several times when I thought it was done, and then realized there could be some improvement, which then usually lead to other things that could be changed. This version is the best I can come up with though, and works pretty well with my craftsman 12V and Black and Decker 20V cordless drills.
The latest things I changed before posting this, were the heights of the cylinders for the drill guides (which were a bit high in prior versions), and I made the Allen wrench slot a bit less tight.
The guide needs a bit of length to do what it does, so very short bits may not work well unless they are extended a bit further from the drill chuck. The STP files are included to make it easy to create different cylinders if other sizes are needed. It is possible to go up to a 13.2mm or 1/2" drill size without modifying the base.
As with all tools, and especially ones that are printed, please use with caution. Make sure your drill bits fit the guides (and that the guides are not worn out). And like Norm always says, wear safety glasses.
If you make one and like it (or not), please post a make. If you see something that can be improved, please post a comment or a remix. I can't guarantee I will be able to make requested changes of course, but if I have the time and can see a way, I may take another crack at it. Thanks for checking it out!
Position the base to print flat with minimal supports. The dovetails will need supports however, below are the settings that worked for me. You may want to use the Cura support blocker to remove supports from the pockets for the M3 screws (6th and 7th pics), they should not need supports and getting those small pockets cleaned of supports can be difficult.
support brim (on)
support interface enabled (roof) at 1.0mm thickness
Position the fence to have it's "legs" standing up vertically so that the dovetails will not need supports. Tree supports which is an experimental feature in Cura, work really well for this part (see 8th pic). The only area that requires some supports is an overhang for the Allen wrench pocket, so the supports can be (optionally) blocked everywhere else.
Position the drill guide cylinder to print with supports touching the build plate only (9th pic), and with the base flat to the surface. Supports should not be used in the threads, and to avoid them, a support overhang angle of 63 degrees can be used if you want to print with supports everywhere. I used more walls than normal (4) on this part since I did not want the drill guides to wear out too easily (they are plastic after all so use your best judgement).
See the 10th Pic. Supports touching the build plate (only) are suggested, in any case no supports are needed on the threads.
Putting it together
First, make sure to clean the "elephant foot" from the parts and also clear any supports. If the surfaces of the dovetails on the base are too rough, they will need to be further cleaned or lightly sanded so they slide inside the slots for them in the fence. Mine just needed the supports to be removed and worked fine.
To start, install the M3 nuts into the base, there are 10 pockets (see 1st pic) and I added a small drop of glue (clear Gorilla Glue) to each pocket, then pushed the M3 nut into the pocket and secured it with an M3 screw through the hole which was just tightened snug to hold the nut in position while it dried. Once the glue dried I removed all the M3 screws from the base.
Next, install the M4x40mm hex head screw into the base, then one washer and M4 locknut are added to hold it on the base, so it will stick up like a post.
Now the drill guide cylinder can be dropped on the M4x40mm screw, and then a washer is put into the bottom of the well in the center of the guide.
Next the spring, another washer and an M4 locknut are installed. The last locknut should be tightened so it is secure, and holds the cylinder down so it stays put. Nothing should be loose.
Then the knob is screwed down which covers the spring.
Optionally, the two M3 inserts can be installed in the fence as shown in the pic. I glued them in using some clear Gorilla Glue, but they can be melted in as well. The inserts are only used to stow extra M3x16 screws so they don't get lost, so if storing extra screws is not your thing, they can be considered optional.
Finally the fence can be slid onto the base. Depending on the orientation you are going to use, you can opt to install the M3x16mm screws in whichever holes are most convenient. I suggest installing at least 2 of them on each side. The screws can be adjusted so the slide can move, or the screws tightened to lock the base to the slide.
The Allen wrench can also be stowed in the fence.
To use the guide, pull up on the cylinder, and rotate to the drill size needed, then let it settle back into the indexing tabs which should secure it in place. If it does not settle in place, the "elephant foot" may need to be cleaned off the base of the cylinder with a file or deburring tool. The M3x16mm cap screws are used to clamp the fence to keep it from sliding freely. The fence should be loose enough to slide easily without the screws tightened down. To lock the base and fence, tighten down the screws, and if necessary, add some more (depending on the side, there are 2 or 3 holes which can be used to clamp the fence to the base). The Allen Key will stow in the slot in the side of the fence. Optionally, there is space to stow 2 spare M3x16mm screws in the edge of the fence, they would screw into the M3 inserts in the fence (if they were used).