Using lock bar

How do you get an axle through a lock bar?

you push it…

I have a set of small diamond files, purchased to ease the edges of the square holes in lock bars, some of which turn out to be slightly too small for the shafts.

If you use high strength shafts, you can also get High Strength lock bars which are precision broached and will never have a problem fitting onto high strength shafts. Available here:

Have you (or anyone) performed experimental analysis to demonstrate how well this product you are so shamelessly plugging, performs against the status quo?

How many broached pieces of .046" flat bar are needed to provide equivalent performance to a .5" thick Gear, or vice versa…

Here’s the “status quo” in a nutshell: if you over-torque a system with a low-strength shaft, the shaft twists. So you upgrade to high strength shafts. Now the weak point in the system is not the axle, but instead the hub of the high-strength gear, which causes the gear to break or the hub to strip. Many people on this forum can attest to breaking gears this way, and many people use high strength lock bars to save their gears from breaking.

Has quantitative experimental analysis been performed: no. Do they keep gears from breaking at the hubs: yes. Feel free to do whatever analysis you wish and add the knowledge to the forum for the benefit of all.

More shameless plugging:
The HS lock bar is a needed VEX component to complement the already existing low strength lock bar. Until VEX decides to produce one and sell it, VEX Team Virus students and mentors volunteer their time to produce these bars, and 100% of the proceeds help to support the team.

hand raised We broke gears before adding high strength shaft bars - and never suffered a break afterward. We didn’t, however, buy them from kmmohn - we made our own based on him sharing his idea. So instead of characterizing what he is doing as “shameless plugging” I characterize it as “helpfulness.” Plus, I’m sure he’s not getting rich off the idea. I’ll bet none of the money is going in his pocket - but is being used to support his robotics program.

Sorry. I totally missed attempt at humor! One of our team parents has a metal shop.

Dremel tool with a polisher bit and a fine file. file any burs and all… then buff

My lockbars arrived with a whole lot of slop :frowning: