From my Journal Tuesday 7th February 2017
I made yet another tool for my Veritas router plane this week. The design of this router is pretty much flawless, let me say that up front, but at my speaking engagement last week I forgot my thumb turn-screw to cinch up the depth limit; it’s one I made to cinch up the lock screw for securing the cutter throughout incremental depth adjustment setting.
I found that the depth of the cut kept shifting to a deeper setting because the “O” ring lock doesn’t truly keep the set like the Stanley & Record routers do using full thumbscrews.
Because I want instant and secure setting, sometime back I developed an improvement to the Veritas model by cutting grooves into the knurled locking setscrew and then made a brass key to fit the channels. It works fine but I improved it further by adding it to an old polypropylene plastic doorknob. You might recall my making something similar to my door–knob camera–mount screw driver mentioned previously here.
By slipping the keyway retro-make into a hacksawed cut in the handle, and then adding a hoop in steel from some steel tube, I have a great way to lock off the knurled locking feature.
Here are the steps:
Use either an old doorknob or turn one on the lathe. I had to search through my stash of ferrules and steel tubes to get one close to fit and then rasp and file the plastic handle to size to the tube. It goes fast and eyeballing it works fine.
I used my existing thumb turn fitted to the grooves. I’d cut in the screw sides and top face that tightens (or should tighten) the “O” ring onto the cutter. This I further fitted to fit inside to tube.
I cut a recess into the knob so that the brass thumbscrew fits inside snuggly.
Removing the outer face of the knob gives access to the inner area where I poured a mix of 2-part epoxy around the brass.
To stop flow out I cut a circle of masking tape to plug the opposite side.
For the steel hoop/ferrule I simply added superglue – this is enough as no pressure is applied to this.
Now my thumbscrew works perfectly and I feel confident that the cutter no longer slips.