I had a lot of trouble with chain skipping coming from the back-side of my chain sprockets so I knew I needed to do something to fix that. Can’t take all the credit here, my idea is built upon the shoulders of giants. I saw @Blsteinhauer88’s Easy chain guide for chain skip and knew that would be a good starting place for my own chain guide.
I had quite a bit of fun drawing up mine in Fusion360. The model and nest files are included in the github repository below. I knew I wanted something clean that was also adjustable. I came up with this:
Link to a360 file (opens in browser, no CAD needed): http://a360.co/2APifTS
It’s two layers of 12mm (~1/2") plywood. I designed the pattern to be reversible, that way I could make one program for both the right and the left motors. I ran two screws through the back of the bigger part to secure the smaller part. You could also glue and staple it if that works for you. The most important part of the assembly is the smaller piece is roughly centered on the larger piece. Maybe I could make a revised version that uses a V-carve bit to engrave it’s position? The only problem with that is then I would have to make two separate programs.
The NC file is programmed to use the 1/4" 1 flute bit available from the Maslow store. The feeds and speeds can be changed either in the NC program using find/replace for other 1/4" bits, or by opening the nest file and changing the tool used for the operations for other sized bits.
As far as mounting to the frame, I made up a mounting bracket from 1 1/2" x 1/8" steel angle. I drilled two holes in one leg that match up with the motor mount. This way my bracket sandwiches between the motor bracket and the mounting bracket I made for the frame. In the other leg, I drilled and tapped two 1/4"-20 holes 42mm (~1 5/8") on center for the guide screws.
That being said, it would be quite easy to simply attach the guides to the wooden stock frame. There may need to be a riser or something in the system to make sure it aligns with the chain sprocket. As much as I really like my steel frame, it requires me to do a little more thinking as to how to attach modifications.
Link to github repository: