Hi, I'm trying to source the parts for a Prusa i3 that I'm building. I found the smooth rods on amazon without much difficulty, but finding suitable threaded rods is proving much more difficult than I expected. I'm in the US, so most hardware places only sell SAE sized threaded rods. Not to mention, metric nuts and washers seem to be much more expensive as well.

I've already ordered a set of plastic parts from a guy an ebay, so unfortunately I can't alter the prints to have SAE sizing. My question: is it safe to buy the next largest SAE-sized threaded rod and drill out the plastic parts for that size? Or should I just stick to the plans and order some metric rods?

There are tons of vendors that sell metric rod online? Mcmaster, VXB, others....

Try using a fastener distributor like Fastenal or Copper State, they supply to contractors and industry but have small retail store fronts. There are others, but I don't know where you live. Just Google "fasteners" + your city. The should sell metric threaded rods and usually can order what you need. Here's a link to Fastenal (they have a ton of locations all over the country): Fastenal

Edited 1 time(s). Last edit at 06/29/2013 08:01PM by Hans_Gruber.

Thanks for all the advice! I ended up ordering metric rods from McMaster Carr. I did know about McMaster, but was mostly concerned about shipping costs. However, all the nuts, bolts, and washers added to the order further diluted the already meager shipping costs. Also, McMaster's shipping rates are much better than many of the Amazon vendors, which sold single rods for $5 + $10 shipping.

I may still print some SAE sized items once I put everything together. I suspect my friends will want some parts of their own, and hardware stores are very convenient around here...