OnePointOneMouse - A Lightweight G305 Mod

Edit 15/2/2026

• Added Back V2.1, with a bigger 7mm rear skate land and a much improved side button(s) holder

• Added a V2 for the front. USE 1 WALL THICK TREE SUPPORTS

• Added a scroll wheel support with larger screw holes. Forcing screws into the old one is a crime against my hands

• Added STEP files for parts I designed or had STEP files to remix from. I appear to have lost the flat versions of the battery cages, or deleted them by accident

Edit 14/10/2025: 

• Added a modified front half that adds a crossbar to reduce twisting of the trigger buttons

• Added an additional battery cage (flat, with no battery supports on the bottom

When my trusty G305 of 5 years started to give me trouble, I decided it was finally time to replace it. Then it went on sale and I ended up buying a second one. Since I now had 2, I couldn't resist taking the old one apart to see if I could fix its problems. And, well, if I had decided that if I was going to take my mouse apart, I might as well start messing around a bit. A week later and here we are, looking at the result of my tinkering: a 40g Gem of a G305 Mod.

Having decided I couldn't give up my side buttons, I downladed krakamoto's excellent remix of Willbot750's wonderful Onemouse V2 design. Immediately, I decided I needed to tinker with it. I had 3 main problems: 

• The first; the side buttons were much further back from the triggers than on the original G305. 

• The second problem; the back-half grips were extremely slippy. 

• The third was the most interesting. As you can see on my make of krakamoto's remix, the battery sits at a strange angle. This is because in the 5 years since I bought my G305, Logitech have significantly shrunk the sensor and made it sit flat on the rest of the PCB. In my dinosaur mouse, it's a whacking great assembly of emitters and sensors and optics sitting right where everyone mounts the battery.

These considerations meant that the mouse needed some fettling.

The result is the OnePointOne. The back shell now places the side buttons just 1.4mm further back than they are on the origincal mouse in relation to the scroll wheel.  The battery holder is now raised well above the sensor and acts as brace for the side buttons. Additionally, the rear-most support has an enlarged footprint to fit a 6mm skate as desired.

Printing Instructions

• Material: PLA (Stiffer than PETG)

• Layer Height: 0.12 

I used 10 walls on the battery cage to maximise the stiffness of the part. The back half used the standard 0.12mm preset

Additional Printed Parts Required (if you don't want to use the included parts)

• Front Half

• Scroll Wheel Support Left

• Scroll Wheel Support Right

• Battery Cage

All are available from both krakamoto and Willbot750's pages. Willbot750's are lighter but more optimised towards resin printing, where krakamoto's remix works off an older version designed for FDM. Both work fine for FDM and I personally use Willbot's V3 parts. They print well enough and are extremely lightweight. 

Assembly instructions are available in Willbot750's channel for the V1, available here: 

I'd also recommend 2 deivations from the instructions given:

• THERE IS NO NEED TO REMOVE THE DPI SWITCH FOR V3 or krakamoto's remix!

• Instead of using one of the long screws from the bottom of the mouse to screw in the furthest-back mount of the PCB, save it for one of the 2 screws used in the front half. You can either pack the hole in the back with a piece of plastic like the priming wipe and use a smaller screw from the mouse, or just leave it empty.

As always, please do post any makes, remixes, pics etc to me, krakamoto, and especially Willbot750, without whom this model wouldn't exist! 

If you got this far, thanks for taking the time to read this and I hope you have a lovely day!

krakamoto: 

• Re-positioned the side-button mount to better match the placement on the original G305
• Added extra bracing to better immobilize the side button PCB
• Cut holes in the grips to improve control and lighten the frame
• Added lands for up to 7mm Dot mouse skates

Willbot750

• Redesigned the battery holder to be more material efficient (stiffer and lighter)
• Redesigned the front half to the same effect
• Added a battery holder variant for older SKU's of the G305
• Extended a brace from the battery holder to act as a brace for the side buttons
• Increased the size of the screw holes for the right hand switch mount/scroll wheel support