My team recently invested in switching all of our Falcon motors to Kraken X60s, rendering all of our Sport Gearboxes functionally useless as there are no adapters for the motor yet. This left my team with two choices, either invest even more money in buying the out-of-stock REV MAXPlanetary gearbox (REV-25-3116) or develop our own gearbox adapter. So that is what I set out to do.
My design that I made could be much sleeker, however I did have a few design goals that led to certain design choices. The first was that I did not want to modify the Krakens - specifically no cutting the shaft. And second, I wanted it to be easy to manufacture - My team has access to a Tormach, making it very easy for me to design something that could be made easily on a Tormach, however I wanted this to be a product that every FRC team could easily make (or get made).
The fundamental design consists of AndyMark’s Carrier Plate (am-4403), and Westcoast Products 8mm SplineXS to 1/2" Rounded Hex Adapter (WCP-1118), totaling around 30 dollars.
The two products are then connected using the Carrier Plate adapter that I designed.
I did have the carrier plate adapter made out of steel on the Tormach, which does break my second design rule, however I am sure AndyMarks 0.5 Hex Hub Extrusion (am-2568) and some careful drilling and cutting would get the job done (I have not tried it though so don’t quote me). That being said, if your team does not have the machining ability to machine steel, I would just recommend getting the part machined through a machining company. One thing to note is that there is a 0.38-inch 3D printed spacer at the base of the Kraken shaft.
The housing was designed such that you do not need to machine anything to make it. The fundamentals of it consists of 3 of AndyMark’s Sport Gearbox Face Mount Spacers (am-3787) and one of their CIM Sport Motor Blocks (am-3770).
That being said, during my early testing of this design I used Polycarbonate 3d printed versions of those parts, and they handled it fine, which makes sense as there isn’t much strain being put on the housing.
Through my testing, I have found the gearbox to stall the motor before the parts get the chance to break. I have not noticed any wear on the parts either, even after stress testing it.
The housing that I am using for this testing is a hybrid between the V3 (the one I have shared above), and the V4 housing (A one piece case for teams that have the capability to machine it). I machined the 3 CIM Sport Gearbox Face Mount Spacers (am-3787) as one part, but used one of our CIM Sport Motor Blocks (am-3770) which I found in storage.
Here are both .step and .f3z files for both V3 and V4. The adapter itself is the same, just the housing is different:
Kraken Sport Gearbox adapter.zip (47.8 MB)
Here is a photo of what the housing for V4 looks like, however I have not machined it yet.
