Two Quick (And yet again very noobie) Questions

[diarmaid]

Hi all,
Here are my questions about materials in the cnc plans I bought:

1) The plans call for 32" of ' EMT 1/2" '. What does 'EMT' stand for? (I searched google but only got Emergency Medical Technician! )

2) Im unsure about the bolt classification. I buy bolts using for example ' M8 100mm ' where the M8 is 8mm diameter shaft and the 100 is the length. In the plans it says I need ten ' 1/4-20 2" bolts '. What do the 1/4, the 20, and the 2" numbers represent?

[CerveloRod]

If everyone would speak American, things would be easier.....

EMT is conduit for electrical wires. I couldn't find what EMT stands for myself, but it is metal conduit for running electrical wires.

The bolt sizes are American, 1/4 inch diameter, 20 threads per inch, 2 inches long.


Good luck.

Rod

[NC Cams]

Electrical (grade) Mechanical Tubing (I think)

Should be 1/4-20 x 2 (again, I think)

[Geof]

EMT - electric metallic tubing? Take your pick. Is that what your plans call for to use as the rails with skate bearings running on? There have been a few threads/posts on this topic; it is not really stiff enough and the wall thickness in particular is quite thin and could deform with a concentrated load from the bearing.

Regarding the 1/4-20 by 2 inch bolts your closest equivalent is M6x1 by 50mm. Just in case you run across some more number combinations; 5/16"-18 is very close to M8x1.25 and 3/8"-16 is very close to M10x1.5

[HayTay]

Explanation of EMT acronym and other terms from m+w zander Int'l. - Facility Mgmt. Glossary:

EMT
Electrical metallic tubing. A very popular metal conduit for nonwatertight applications. Also known as thin wall.

Lots of other common, and not so common, terms and phrases for all kinds of industries explained. Check it out!

Note the alternate name for EMT is "thin wall". This is what makes it not very stiff and easy to bend under load. That's why they use it for routing electrical wires over, around, and through commercial and public buildings. That's why most people don't use it for their DIY CNC tables. Go to the plumbing section and look for the same size black or galvanized pipe, instead.


I hope that helps to clear things up,

HayTay

[2muchstuff]

A stiffer alternative to thin-wall is rigid. It is used for electrical wires but it has thicker walls.

[Geof]

Workshop Progress Meter
Planning Stage:[===========|-----] 60%
Generate Funding: [==========|--------} 55%
Source/Buy Eqpt:[=========|----------] 50%
Setup/Operation: [--------------------] 0%

Has this progress meter changed or are you stuck in a stasis field somewhere?

[diarmaid]

Thanks for the info all. I guess I won't be using the EMT after all, I'll find something more rigid.

Yes the progress meter has changed Geof!

The funding bar is changing 5% each month until my savings mature. Im getting seriously irritated with waiting, but if I take the money out early I lose 25%.

The planning bar was going up steadily for a while, but the more I plan, the more I find I need to plan & I'm now worried its going to reach 100% while Im still planning so Im not increasing it!!

I figured I'd give myself a year to plan and organise everything. I joined this site in late March ( Yes you've only known me two months!! ), and I have 8 months of harassing everyone left ...........I think I gave myself too much time to plan.....my bad...

Edit: Progress Meter is now updated!!

Edit 2: Did anyone notice I've been promoted and am no longer a chip sweeper!