What Acme threaded rod to get?

[CNC Darren]

I am going to order my Acme threaded rod from MSC Or hopefully go pick it up as there is a MSC store 5 minutes away from me and beat the shipping charges. They list 1,2 and 5 start in thier pdf catalog? Just wondering which one you guys use?

Darren

[InventIt]

I used 5 start with 440 in oz steppers. Most use 1 or 2 I think. I really like the 5 though. I can get over 500 IPM! Don't like to run it that fast though.

What are your design specs????

[InventIt]

BTW, it's a good idea use a dial indicator and check the screws for straightness after you cut them to length. They can be slightly bent when you get them. The closer to perfectly striaght you can make them the smoother and faster the screw will turn with out binding/heating/whiping etc.

[ger21]

What size motors do you have?

[CNC Darren]

I will be using the 80 in/oz motors from Hobbycnc and building Jgro's first generation machine, with different lead screws and a few other of my ideas mixed in.

[ger21]

With only 80 oz, 1/2-10 might be too big. You might want to look at 3/8-12 or 3/8-16 acme. Single start only.

[CNC Darren]

ok, going with Precision 3/8-12 single start, now my question is either low carbon steel or alloy steel?

[ger21]

The alloy is stronger, I believe.