Rolling Tally Counter

Here is my rolling tally counter design.  It can count up or down from 00 to 99 with one wheel for the ones and one wheel for the tens.  

My original design just had a serrated knob to turn.  However my printing turned out rather stiff, so I also added an alternative knob (knob2) that would attach to a handle piece to make turning it easier.  

The first person who posted a make had the opposite problem (too loose), so I think maybe it's my printer or print settings that are to blame.  So I now have 2 versions of all the female parts.  If it's too tight, use the parts from the “Large Clearance Parts” folder.  The male parts are the same.  Large clearance parts have a 0.025 inch clearance.  Otherwise, the clearance is 0.010 inches.  You can check what clearance is right for you using my clearance tester (0.25 Inch Clearance Test by nightfox90 | Download free STL model | Printables.com) and if you are having trouble getting it to work for you, please let me know in the comments.

The assembly requires one of each piece except if you are using knob2 and the handle, you won't need knob1 and if you are using knob1 you won't need knob2 and the handle.  

When assembling the counter this is the order of assembly onto the “Body” piece:

1. Knob
2. Driver
3. 1s
4. Driver2
5. Gear
6. 10s
7. Body2

Be careful that you don't break the pegs off of the driver pieces when inserting them.  When doing the 1s it's a good idea to have the peg turned away when inserting the 1s piece to reduce the risk of breaking the driver.

When you assemble the 10s, make sure that it's set so that the 10s turn between the 9 and 0 on the 1s.  So set the 1s to 9 then set the 10s to where it's starting to turn. For the 10s you should be able to carefully drop the 10s part onto the peg with the 1s set to 9.

The body2 part can be attached to the body using screws.  the handle can likewise be attached to knob2 using a screw.

I included some renderings with the body parts set to transparent.  Hopefully, this makes it a little easier to see how this goes together.

I designed and modeled this using Solidworks.