2 start vs. 5 start

[bradtal]

Hello All-

I've built a Joes2006 machine and have had pretty good luck with it so far. However, I tend to run into some issues after awhile. For example, I've been making some cool pencil holders and have a large order for them. I'll make like 15-20 with no problems, and then suddenly, my x-axis (long axis) will skip steps and it ruins the board I'm cutting from.

I'm currently using standard 1/2 inch threaded rod. I've always wanted to "upgrade" to the 5-start 1/2 rod from McMaster-Carr. After doing some research, I see that people are 50/50 on whether to use 5 start or 2 start.

I'm using the HobbyCNC board with 305 oz steppers with a 24V transformer.

I've read that steppers have more torque as slower speeds, so the 5-start makes sense to me. But then I also read that your motors have to be "strong enough" to be able to turn the rod at that slow speed.

I guess after all this typing, my question is... What makes more sense? 2-start or 5-start? I don't want to invest a bunch of money and regret it afterwords.

Thanks for your help.

Brad

[BobF]

Brad,
I built joes2006 as well. I used 1/2-8 2 start. This gives 4 tpi. Lots of the builders of Joes 4x4 have used the 1/2-10 5 start, which gives 2 tpi. I think that will work on the 06 and am looking into getting some, but don't have any yet.

I can tell you that the 1/2-8 2 start works well.

[calgrdnr]

Howdy Brad ,

I switched out my 10tpi 1 starts to 5starts . I can now routinely cut mdf at 150 ipm I have rapids of 320ipm. I went with the 4 Axis HCNCPROPKG Package w/ 200oz-in Stepper Motors. I used to have problems with Zaxis losing steps, since the change I have had no problems. I am sure it is because the torque is greater at lower speeds ( only use 30ipm for Zaxis)

you should also check to make sure acceleration not set to high this can cause you problem I believe.

good luck Kent

[bradtal]

Originally Posted by calgrdnr Howdy Brad , I switched out my 10tpi 1 starts to 5starts . I can now routinely cut mdf at 150 ipm I have rapids of 320ipm. I went with the 4 Axis HCNCPROPKG Package w/ 200oz-in Stepper Motors. I used to have problems with Zaxis losing steps, since the change I have had no problems. I am sure it is because the torque is greater at lower speeds ( only use 30ipm for Zaxis) you should also check to make sure acceleration not set to high this can cause you problem I believe. good luck Kent

Kent-

Thanks! This is exactly what I was hoping to hear! Thanks also for listing your specs. Made it easy to compare your setup with mine.

Brad

[calgrdnr]

Brad,

Glad to be some help, that is what is so great about this site . Ask and you get answers. might not always be real quick or what you want to hear.
but you will get responses.. Please make sure to share some of your results of your creativity and your CNC .
let us know how it work Kent

[AJ Negvesky]

I have finally finished cutting out and asseblinng all the pieces for Joe's 2006 R2 and went with the Probotix

3x SideStep Bi-Polar Stepper Motor Driver
2x HT23-400-4 400ozin Stepper Motor (X- & Y-Axis)
1x HT23-260-4 260ozin Stepper Motor (Z-Axis)
PBX-2 Parallel Port Breakout Board
24Volt 4.3Amp Switching Power Supply

Mach3 and Vcarve pro V5 software


I now need to select the lead screws. I understand 5 start would give you higher speed, but do you loose accuracy? Any help on which way to go and what the settings would be best in Mach 3 would be greatly appreciated..

[TchTchr]

Are three anti-back lash nut and flanges needed from dumpstercnc when going with the 5-start?

thanks,
Brad

[Realmseeker]

Does McMaster carry the 1/2-10 5 starts? i am having problems finding it on their site. Can someone link it please?

Seems about 40$ for 1/2-8 1 or 2 starts vs 60$~ for the 5 starts on 6' lengths,
Basically adding about 40$ to a build,
Even on a budget,
thats not to bad

[AJ Negvesky]

http://www.mcmaster.com/#=1jlp9n

[AJ Negvesky]

search for number
steel
99030A704 $60.74

Black-Oxide
98940A020 $82.26

[Realmseeker]

much thanks AJ

[TchTchr]

I found the answer to my question below in the parts spreadsheet.

3 backlash nuts and flanges

sorry for unneeded post