[bobmagnuson]

There is an obviously a slight difference in weight, but are there any advantages/disadvantages to using 2 pieces of 2 1/2" CRS vs. a single 7" piece?

[vtx1029]

I'd say $ being the biggest factor. The good thing aobut the smaller pieces over the 7" one is you can adjust the edges so they are parellel to each other. good thing about the 7" is you don't need the clamps.

[bobmagnuson]

Surprisingly, there is only about a $20 difference, 7" being more expensive. That difference is negated by the cost of the number of clamps I'd need over the 84" length.

[ahren]

Bob,

If you can get actual 7" cold formed, that's a good way to go. It can sometimes be dicey to get this material, as it is sometimes sheared from sheet rather than cold extruded like the 2.5" stock, which means the edges and dimensions are not nice and square, so make sure to check on that.

For us, shipping and stocking are easier if all of our material is 2.5", so this is more cost effective in the end for our kits. If you are making your own rails, and can get nice 7" material, I'd go for it! This should be somewhat stiffer as well.

Best regards,

Ahren
CNCRouterParts

[bobmagnuson]

I'm resurrecting this old thread... Is there an optimal number of bolts or bolt spacing for attaching the 7" plate to 8020 extrusion? Such a thing as too many bolts?

[ahren]

Hi Bob,

You can never have too many bolts In general, we bolt our steel down every 6", and 3" from each end and this has worked well. If you want to go closer pitch than this you are welcome to.

Best regards,

Ahren
CNCRouterParts

[bobmagnuson]

Thank Ahren. I think 40 bolts should be enough...

[nlancaster]

That looks like a perfect match on the paint there bob. Great looking machine.