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View Full Version : New build square tube thickness.


shikha829
Mon 13 August 2012, 04:26
Starting 8' x 4' build, decided to use 100 x 100 mm square tube with 5 mm thick is it fine?

KenC
Mon 13 August 2012, 05:53
5mm wall is thick enough for tap hole up to M8x1.25, that will save you plenty on bolt cost since it is the common size. 1.0 pitch crew bolts are expensive. At my place, M8x1.0mm screws are many times more expensive (RM2.00/pc) length & cap head selection is limited, & I have to wait for 3 week. M8x1.25mm (RM0.35/pc) its off the shelves & plenty of cap head & length to choose from.

I really can't say much about how much load it will take. That has a lot to do with the structural design...
You also have to offset some dimension so that all the parts will fit nicely & not getting on each other's way.

Anyway, go for it if you had decided that it will work. Keep us posted on the results.

Gerald D
Mon 13 August 2012, 10:06
You are obviously not following the MechMate plans, so I don't want to get involved in a discussion on thickness if we cannot see your detail plans.

shikha829
Mon 13 August 2012, 22:06
Thanks Gerald/Ken,
Gerald yes not following MechMate, but need help from you about tube selection structure.

Can I use 100 x 100 mm 5 mm thick /or 6 mm thick, want to know using 5mm thick tube rather then 6mm can take vibration and give me sturdy strucutre.

Table size : 3050 x 1525 mm
Working area : 2500 x 1300 mm
Gantry height : 300 mm from Casting
X axis tube : 200 x 100 mm 5 mm thick.
Motor : nema 23 / 34 stepper.
X & Y Transmission : Rack 1.5 Module / Pinion
Z Transmission : 16mm rolled ballscrew.
Spindle : 2.2 KW

and here are some pic of my design.

Please help me to design my machine.

KenC
Mon 13 August 2012, 22:13
build one with 5mm thick tube & another with 6mm thick tube, AND tell us if there is any difference. We sure would like to learn more from your experience.

shikha829
Mon 13 August 2012, 22:18
:):):):):):)

Ken, i will try, but i have budget for one only this time, surely i will pots.

Gerald D
Mon 13 August 2012, 23:30
unsubscribe

bradm
Tue 14 August 2012, 06:24
<sigh> I guess it's my turn:

Shikha, please don't take this personally. It looks like you have some interesting ideas about building a CNC machine, but this is not the forum for brand new designs. I suggest that you use CNCZone for that.

While it is true that we occasionally look at, consider, and help with designs that extend the proven MechMate design a bit, this forum is centered around that one design. That's the area of interest for most of the people here, and the forum is complicated enough with just one major design.

I know that many of us are also members and participants at CNCZone, and when we are over there, we're interested in looking at new designs. But when we are here, at the forum titled "MechMate", we discuss MechMates.

So, I respectfully suggest that you start a thread at CNCZone for your non-MechMate design. While there, you can also see how others have approached building linear slide based machines. Of course, should you discover in the course of your design and research that you want to build a MechMate, we'll be happy to help.