Changing the Shafts on a Toughbox Nano

My team has to change the shafts from keyed to hex on a toughbox nano to fit new wheels. It is just a solid piece of channel, so we can’t exactly open it. I assume it is possible, since the AndyMark page sells replacement gears and shafts, and I looked through the assembly guide, but I can’t seem to find a replacement guide. Have any of you tried doing this, or something similar? If so, how much time did it take, and are there particular things I should do to make it easier, challenges I should expect, or tools that will make things go quicker? Thank you for your help.

From what I understand, all you have to do is take the klipring off of the output shaft. Then you should be able to pull it out. After that just repeat the steps for the output gear/shaft from the assembly guide with the hex shaft instead.

I took the gearboxes apart last year, if I remember correctly you can take the screws out by the bearing. This allows you to slide the gears out and the shaft connected to the middle gear. They may be a snap ring on the output shaft. Just remember which way the bearing are facing, one problem that can happen is the gears pressing against the bearings if put on the wrong side or way.

That is actually a fairly easy mod! All you will have to purchase is the replacement output shaft of your choosing. The gears are all hex broached already. The hardest part will be removing and replacing the E-clip.

Step 1: Remove the e-clip.
Step 2: Remove the shaft from the gearbox, ensuring to not lose the spacer or gear. I would take a picture just so you remember the proper orientation. Biggest thing to remember is that the boss on the gear faces the bearing.
Step 3: Place new shaft through the hex bearing into the gear and spacer.
Step 4: Replace the e-clip.

Tools: screw driver or e-clip tool and a hammer.

Time: approximately 15-20 minutes your first time. A lot less the next few.

My team has had nightmares with toughbox nano’s in theory it’s easy but it’s such a tight space. Good luck.

Andymark has the assembly directions posted on their website. I found them on the Files and Documents tab of the TB-nano page. Follow them in reverse order, then going forward with the new gears. While you have it apart, inspect all of the parts for wear and the bearings for free spin.

We used these gearboxes last year and custom made output shafts on a lathe from 7075 Hex, very straight forward. The output bearing is an R8 size, use hex or round as needed.

You simply pull the E Clip out, and disassemble. I found a open ended wrench worked well to push the E Clip back into place above the gear ( tight area to work)

The upper mounting holes have very little ( inadequate really) clearance with the mounted CIM motor. We had to machine the 10-24 cap heads down in diameter to not have a interference condition.