I’ve read thru the forums and most of the solutions for mounting drag chains are based on older designs that would require apart and drilling holes (might be my only option).
I have the standard sized Shapeoko 3 with HDZ and I would like to relocate the controller to the left Y. A watercooled spindle may be in my future. I have seem 15x30 and 15x40 chains recommended for them.
I was considering a 15x40 but I am unsure what bending radius I should get. I was looking at Luke’s post
And I noticed he linked (and the pictures he provided look like) the 15x30 and the link says R38. I found in another post where he mentioned he thought he settled on 15x40. I would comment in those posts, but they are closed.
So, 30 or 40? What bending radius?
I think Luke nailed it in that post as far as how I would want to route chains, but I’ll have to drill some holes in my X endplate because the 2 holes he mounted his bracket do not exist on my plate.
On this I did find the best thing to do is drill and tap the extrusions. I found 15x40 is about right, although 15x50 also works well. Bending radius will vary based on the height of the mounting points, I prefer a larger radius as it puts less stress on the cables/water pipes.
Length wise, I think you need 2m for a standard S3, 3m for a XL and around 4 for an XXL.
Make sure you get ones that clip open/close. I tried to thread a standard DC once. Not worth the time.
Took some measurements and trying to math out the bend radius.
Measured from the top of my X rail to the top of my X stepper (as mounted on the HDZ) is right at 90mm, so that would be a radius of 45mm. So… I guess R38 would be the desired radius.
Now to decide if I should just go with 40 just to have that extra room for the spindle’s water cooling tubes when/if I get one. I’m still on the fence about that.
I spent quite a while looking at drag chains and routing when I did my 2.2kW spindle upgrade.
In the end I decided it was better to simply put a new pair of chains on the machine for the spindle power cable and coolant pipes and leave the Shapeoko wiring as it was. The main reasons for this were to reduce the risk of interference between the spindle motor cable and the shapoko wiring and to get a much wider bend radius for my coolant pipes. Many people have interference problems once they’ve upgraded to a VFD spindle and a few cm of separation buys a lot of reduction in EMI.
The drag chains I used were R38 18x37mm for the spindle wiring and plumbing, they’re 1 meter chains which I swapped a few links between to get sufficient length for the X rail chain which is a bit longer. They’re openable for inserting the wiring and hoses, I removed and reversed one end plate on each chain.
The R38 spec bend radius of the chain is a lot smaller than what I see in reality, as Luke says, the mounting points for the drag chain are key in controlling the bend radius, between those and the fairly stiff PU pipes the bend radius is pretty wide, especially compared to the standard Shapeoko chain routing which would have required a much smaller bend radius.
I agree that that taped on chains are a PITA, I added extra aluminium brackets for mine and drilled & tapped the extrusions to allow for proper mounting. Adding the extra supports (other folks have 3D printed prettier looking ones) also dealt with the issue of the standard X chain slipping off the back of the X extrusion, it just slips out onto my new brackets, it’s also screwed down to one of the new brackets instead of double sided tape.
