[Dropout]

Good morning all.

I'm trying to convince someone that a small CNC is a better idea to turn threads than a manual lathe.

What would be a reasonable ballpark time for cutting 1 1/4-8 threads 10 inches long from 1018 or similar?

Does this kind of job need CAM or will a controller have the smarts to do it?

Thanks.

[Shane1234]

how long are your threads? is this just a threaded rod (all-thread)? how many will you be making?

if its all thread, you should look into a thread roller tool for your manual, you will save tons of time.
if its just threads on the end of a part that has a shoulder or same diameter as the thread, cnc might be the way to go IF, and i repeat IF, you have a nice run and will continue to have runs. CNC's are a plus to have when your jumping from setup to setup on different types of threads, but if you only gonna make a few parts, it doesnt justify the cost.

[Geof]

Having cut threads on big and small manual lathes and big and small CNC lathes I can tell you CNC is much faster. For the diameter and length you give it would probably be faster to do a single one by CNC than doing it by hand, and this would involve handwriting the G-code for the threading.
Actually cutting 1-1/8" - 8 on a small manual lathe would be a challenge because the width of the flank is so large most small machines would have difficulty driving the cut.

CAM would not be essential to cut a thread like this. CNC lathes normally having dedicated cycles for threading which just require a few dimensions to be entered.

[Jhjr]

I'd say around 5 minutes once you have a good program. Could be faster depending on the machine. If your used to threading on a manual lathe watching a cnc thread is pretty cool since on a manual you'd thread that around 50 rpms or so & cnc you can crank it up. Prob 500-1000 rpm depending on your max machine feed travels.