[piperpilot]

Hey folks,

I wanted to get a quick opinion. I have seen mention to "Flat Ground" stock in a few threads, but it seems like most people are using "Cold Rolled" stock in their builds. It doesn't look like the Flat Ground is that much more expensive. Is there a reason why everyone is using the cold rolled?

I saw mention in a couple of threads that the cold rolled steel could be off a bit and affect precision, so it would make sense to go with the precision ground stuff.

If anyone can comment, I'd appreciate it.

BTW...this is for the cncrouterparts linear motion system.

Thanks,
Curtis

[gmfoster]

I don't see where you are finding it for any ways near the same price. The only reason to use cold rolled as far as I can figure is price..


An example 1/4 x 2 2 foot long

both 1018
Cold rolled 12.65
ground flat 27.28

Almost double. Where are you finding it for the same price?

And mostly I can only find higher grades of ground flat at much higher prices.

AS I say I would be interested where you are finding it for the same price....

Garry

[piperpilot]

OOPS...OK...you are right. I was comparing the costs at FLA but that includes labor for the drilling and cutting. I just compared onlinemetals.com (CRS) and amtektool.thomasnet.com (Ground) and came out with the following:

1/4"x2"x24"
CRS - 12.23
Ground - 27.28

1/4"x4"x24"
CRS - 18.68
Ground - 43.37

1/4"x6"x24"
CRS - 24.24
Ground - 62.91

so my statement of "not that much more expensive" is not correct. So I guess the answer is...if cost is not important, then one would go with Ground stock.

I guess the big question is...is the precision of ground stock worth it, or is CRS good enough? I'm guessing CRS is good enough.

Curtis

[Mountaincraft]

I would be wondering at what point the cost of using the flat ground material with CNCRP bearing trucks becomes expensive enough that industry standard precision linear rail systems are a better option...

The whole point of the CNCRP system is 'bang for buck' right?