Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: tashby on July 03, 2008, 06:06:08 PM

Title: size of screew
Post by: tashby on July 03, 2008, 06:06:08 PM

i am very new so please help
i use 1/4 x 20 for my screews
what will i have to do change to a larger screew, maybe 5/8

Title: Re: size of screew
Post by: Hood on July 03, 2008, 06:19:23 PM

Not really sure what you are meaning, can you try and explain further.
Hood

Title: Re: size of screew
Post by: jimpinder on July 04, 2008, 03:29:09 AM

and why do you want to change.

Title: Re: size of screew
Post by: tashby on July 04, 2008, 04:18:38 PM

I am talking about the drive screws. A larger size would seem to be more rigid. If I speed my movements up I
get a viberatuon.

Title: Re: size of screew
Post by: Hood on July 04, 2008, 04:44:52 PM

only you can know what you will need to change as we dont know what your machine is like. If you are meaning from a software setting point of view then if you get the same pitch screw but just bigger diameter then you wont have anything to change in Mach. That is assuming you keep the same size timing pulley if you have one.
Hood

Title: Re: size of screew
Post by: tashby on July 04, 2008, 06:46:17 PM

Thanks Hood. You answered my question.
I told you I was new and only people like you is the way I will learn or by trial and error.

Title: Re: size of screew
Post by: fixittt on July 08, 2008, 08:25:19 AM

if you can get away from the 1/4-20 screws I highly recommend it!  I have 1/4-20 acme screws on my maxnc machine and I can tell you this,  if one of your backlash nuts locks up the screw will bend easy!   Also with the 20 tpi screws you in theory get more accuracy but sacrifice speed.  The maxnc type of machines are soo poorly built that any accuracy you gain from the higher tpi screws is lost in the flex of the machine.  Remember that accuracy is in the SUM of all components!