Introduction: Homemade Thumbscrew
This instructable will show you how to make a custom thumbscrew with parts you probably having lying around. You can go to step one now or read the back story as to why I can up with this.
I am in the process of buuilding a custom folding-hideway workbench. One of the things I want to do is have mounting points for my tabletop devices such as a Drill Press, Dremel shaping table, vise etc. But because the bench top folds away I need to be able to securely attach and remove the tools easily. So I will be putting threeded insert screws in the bench top in the appropriate places for my bench top tools.
I also wanted to be able to loosen and tighten the screws by hand so I didn't have to worry about having wrenches or sockets available.
My initial idea was to use 1" knobs that had the correct thread bolt in them. But they cost anywhere from $5 to $15 each and I need at least 12. So I set out to make something cheaper.
Step 1: Supplies Needed.
- A screw or bolt. ( I used a 1/4-20 screw, but any size to match your application will do)
- A nut (to match thread of bolt)
- A washer (to match diameter of bolt)
- Loctite Red (or any high strength thread locking glue.)
Step 2: Apply Loctite
Following the directions of the adhesive you are using, apply some to the tip of the threads.
Step 3: Thread on Your Wingnut\washer
Put the washer on first, then thread on the wing nut. I went one thread past the end to make sure it was secure. You will need to wait until the adhesive sets. In the case of Loctite Red, it's about 20 minutes.
Step 4: Cut Off Head of Screw
Now that the wingnut is secure, you can cut off the head of the screw or bolt.
Step 5: Clean Tip of Threads and Test
Depending on how you cut the head off, you may need to clean up the tip a little to allow a nut to be screwed on. Once cleaned, use a nut or, in my case a threaded insert that this will ultimately be used for, to test the threads on the cut off end.
Step 6: Test in Your Aplication.
This is one of the tools I will be scuring with these thumbscrews. The bench is not built yet, so this is a scrap piece of wood with the threaded insert installed.
As you can see in the second photo here, the screw is too long and will not tighten down. You have a choice here. You can either cut the screw a little shorter, or, as I did in the last photo, I just added a nut to it. Now it tightens down. I prefered this way because this now allows me to use the screw for other devices that may need the screw to be a bit longer
Step 7: Addendum: Alternate Means to Attach Wing Nut
Based on some users suggestions, I'm showing an alternate way to attach the wing nut to the bolt or screw. Thread the wing nut onto the screw so the "wings" are facing the head of the crew. Thread the wing nut up until tight
Based on the screws I was using, the head of the screw was too wide, so I marked off the excess part of the screw heard and grinded it down so it was as thing as the wing nut. If you use this method, be sure to wear gloves. The screw will get hot.
Once you have the head shaped the way you want it, secure the wing nut with Loctite, solder or weld.
I found this process a big cumbersome and for my liking, I will probably stick with my original process. However, I will put a nut on the screw so that once the head has been cut off I can remove the screw to repair any threads that may be damaged due to the cut.