Paging @Richard_Horne ! (The only button I can find to contact you is hangouts, and don’t want to wake you at 2 or 3am local time!)
Looking at the following picture of the Bowden extruder…that diagonal piece at the 3 o’clock position? I’m to remove that to finish assembly, right? It’s the only way I can see to complete the tensioner…
Ah well, off to hob a bolt!
And where do folks find springs to tension things?
Yes, you need to remove that. I use springs from pens.
I buy springs from a surplus store, Amazon or home depot when in a hurry, or from aliexpress, when I have time to wait for the show boat… from China
I found springs at a local hardware store, I think it’s an Ace affilitated one. I could never find the right size at Home Depot or Lowe’s.
I use a couple of chunks of silicone rubber cut from an Ikea trivet between two washers. Works ok, but it makes it too easy to over tighten the bolts. I find that 1.75mm bunches up between the bolt and Bowden if it’s too tight, vs. 3mm which needs more force.
I’ll go hit the hardware store tomorrow. I ‘made’ my own hobbed bolt by chucking it in the lathe, chucking a tap in the drill and rubbing one against the other for a bit. Holy Crap that worked GREAT…unless it ends up wearing (which is doubtful…PLA is relatively soft). It’s not hobbed, per sé, i’d have had to somehow synchronize the two…it’s more a bunch of spikes in the threads…anyway, holding the two pieces together, there’s a LOT of friction available to grab the plastic.
You smoke.
Neat! I just printed this exact printer, 3DR yes? I printed that extruder piece in thermal reactive green so it’ll change colors as the machine runs 
Yeah, extremely well designed build, hope it prints as well as it looks!
Only thing I didn’t like was the rod & joint adapters. They are pesky tiny things to print and you gotta do 12 of them!
I used RC Plane parts…not cheap. I still may swap the all thread for CF, too. https://www.youtube.com/watch?v=c6MFxMl9axs
Whoops…wrong vid. https://www.youtube.com/watch?v=XwubfPsznxc
@Andrew_Litt - you had me at IKEA. It’s one of my goals - to have a printer (mostly) sourced from IKEA. Using the silicone trivet as absorber stock is great! And they’re fairly cheap, iirc.
@Mike_Miller - bit slow on the page - looks like you have this under control, good luck with the build. I have also used silicone rubber for the idler, it works well.
Yeah, with the exception of the RUMBA going all smokey, things are well at hand.
