What are these parts?

Our assembly is going well. I’m pretty sure we have all the bits we need, and maybe some bits we don’t:

What are they, where do they go, and where do they appear in the assembly guide?


1 Like

Aha! The “what’s in the box” page gives me captions for the parts… when I view it on my laptop. When I view it on my phone I see pictures, but no captions.

So, I know what they are. They’re “chain alignment spacers”. However, I don’t see them mentioned in the instructions.

1 Like

The location of these parts is dependent on whether you are running the chains over the motor sprocket or under (you will be asked about this in the initial calibration setup)

over the sprocket (this entire subject post is a very informative for different options on chain tensioning)
Thanks to @Dustman for this excellent picture

but basically they are placed on the slack side of the sprocket to keep the chain from crossing itself and to keep more chain links in contact with the motor sprocket to reduce chain skip.

hope this helps

1 Like

I personally used the over the top chain position with weight on the idler sprocket hanging down from the end of the top beam

weight provided by a 2 liter soda bottle filled 1/2 full of imported water (imported from my kitchen tap that is). drilled a hole through the lid to run a length of cord through and tied several knots to keep it from pulling back through with a loop on the other end to connect to the s-hook on the idler sprocket. Distance from top of bottle to idler sprocket s-hook is about 3 inches. Repeat this for the other end. I used paracord but you could also use part of the excellent bungee cord that came with Bar’s kit using the zip ties to create the loop and/or the knot inside the lid. I also used the bungee for the z-axis tensioner over the top of the router (RIdgid - reinstalled the handle bolts and used zip ties to create snug loops in the bungee to fit over the handle bolts - I left a little extra length to the bungee in case I needed to loosen up the tension on the router.)

I also used a spacer on the frame to keep the slack/weighted side of the chain parallel to the motor sprocket as it drops down. (I used cheap pte cutting board material to cut down on friction - round over the edge the chain comes in contact with to prevent the chain from catching - some people have used actual pulleys for this but I am cheap and impatient)

1 Like

using a weight instead of a bungee is good, but having the slack hang down is
not so good, gravity swings it back from the sprocket and makes it more likely
to jump.

That’s why the chains across the top beam is the recommended approach. you can
have the weights hooked to the chain with paracord and then it doesn’t matter
that they are angled, you aren’t twisting the chain.

David Lang