Summary:
Version 2 in all it’s glory.
This is a CNC machined peg-vise. I intend to use it mostly for soldering, but I suspect it will have applications for jewelry making as well. Using pins in place of regular jaws lets me grip round, and or strangely sized PCBs with at a minimum 3 points of contact. This design may be familiar to some people, it is frequently called a “ring vise”, and is also used for holding the ID of cylindrical objects. I won’t confirm that I have plans in that direction, but I definitely won’t deny it either…
Reflections:
Like all projects in this series, I consider this to be a “learning project”, with all of the associated clumsiness. I am very pleased with the final result, but it did take three tries. Personally, this was a great chance for me to learn about reamers, and fits, before having to use them for ME72, or the Knife Grinder project. For a summary of the three versions of this project please check below.
This project also gave me a chance to try out micmaster’s threaded rods and knobs. They are a touch expensive, but as a way to reduce the project complexity I am really pleased. I did end up taking a facing cut on the knob to get rid of what looks like a saw-finished surface, but the knurling was good quality, and the other surfaces seemed nicely turned. The part number is 5125K32, and it can be had for 6.20 per unit.
As always, if you have any questions or want some help attempting this project for yourself please feel free to get in touch.
CAD and CAM files: [Files] (before bushing)
Versions:
Version 1: Version 1 suffered from alignment issues during the initial cutting, and I reamed the holes slightly too small making it impossible to disassemble (or move) the vise once put together. I do like this picture though…
Version 2: This version actually “worked” in the sense that it looked good, and could be used as a vice. Unfortunately, a dull reamer resulted in over-sized peg holes, and misalignment during final gluing made the ways somewhat sticky when the jaws drew close.
Version 3: works perfectly, I am really pleased with the way it turned out. Mostly identical to version 2 from a design standpoint, although I did drill out the screw shaft and add a bronze bushing.
Fabrication:
This project has 4 major fabrication steps: Stock prep, machining, polishing, and fit-up. The process I used for each is laid out as follows.
Stock Prep: The first step in creating this vise, is to cut the two pin holders to length. Since the width and height are not critical dimensions, I choose to cut them both out of a bar of 1.25in x 1in, aluminum stock. I then milled both blanks down to 3.000in on the manual mill. This dimensions is not strictly critical, but for aesthetic reasons I suggest trying to hold the difference to under 3 thou.
Machining: The machining for this project took place in two operations. First, each peg hole was drilled 1/64th undersized, and then reamed to size. I found a nominal-size reamer produced my desired fit, but your mileage may vary. Next the pieces were flipped, using a work-stop to keep the coordinate system consistent, and the way pockets were cut. As with the upper holes, the actual way holes were drilled 1/64th small and then reamed to size with a slip-fit reamer. The spring reliefs were bored, and the screw holes were drilled and taped as appropriate. This process took about 30 minutes all told.
Fit-up: For versions one and two, the final assembly was a fairly involved process with a lot of hand sanding to get things to fit. None of this was required for version three, so I just coated the way-holes with slipfit-locker and pressed the pins in. I did find it helpful to run the moving jaw along it’s ways during this process to enforce parallelism.
Polishing: In the final iteration of this project, I ended up first completing the fitup, and then sanding all of the edges completely flush. After that, I went ahead and used the scotchbrite wheel to put a brushed look on the parts, and then followed that up with a medium-weight scotchbrite pad to knock off some of the luster.
Lessons:
By far my biggest takeaway from this project is that using sharp tools is really important. The first time around, I used the standard shop reamers, and had a lot of trouble holding reasonable tolerances. The second time I cut this project, it was with brand new reamers , and the fit improved dramatically.
Another big takeaway for me, is that a few purchased parts can make a project much more feasible. Machining the knob, threading the screw and winding the spring would all have made the project more “authentic”, but it also wouldn’t have happened.
Finally, and this should be self evident: thrust bushings are really important for reducing friction. Between the second and third iterations of the vise, I added an oilite thrust bushing around the knob. It significantly improved the friction, and generally made the vise feel nicer to operate.
The “stationary” block, the center pocket provides space for the spring when closed.
Using locktite 638 to lsecure way-rods let me use the same reamer for both blocks.
Version two clamping a set of the shop keys.
A demo of how gripping a PCB would work. From before V1 was assembled of course…