Conduit

[Tom Brown]

I'm kicking around the idea of using 1" galvanized conduit, instead of gas pipe in a Joe2000che clone router.

It seems to me that it would be just as good material choice, given that it will be well supported across it's length.

Any comments or ideas?

[vladdy]

Gas pipe has a thicker wall, and is more rigid....less flex especially if you have heaver tables, work pieces or cutting loads..
The thicker the wall, less flex, more weight and cost..
The harder the material, less flex, more cost [usually]
The larger the diameter, less flex, more cost [and larger associated parts]

It's a lot of tradeoff compromises, gas pipe is pretty cheap, easily available, and reasonably rigid...
larger diameter , harder pipe with thicker wall sizes [like seamless tube], will give much more rigidity, but at the expense of larger support items such as carriage parts, supports, bearings, etc..
the most versatile and reasonably cheap is steel , as opposed to harder aluminum alloys, carbon fibre, trussed wooden composites..
best choice [imho] is plain old cast iron, and lots of it...but not ideally suited to a hobby grade machine, prettiest is aluminum..

basically I feel that conduit would have too much flex, and the time involved to support it better, or to go to a noticably larger diameter isn't worth the bother as the cost between gas pipe and conduit isn't that much..

enjoy..

[beone]

This is what I did on my router. 1" conduit in torsionbox frames. I have had no problems and the machine is solid and very rigid. all the conduit does is provide a had place for the bearings to run. See my thread "BEONE

[beone]

Sorry the cat stepped o teh keyboard and sent the last too soon. my thread is 'BEONE's first router. I also used 1/2 ply instead of mdf. for a torsion box I tink it has better stability. I just built a new router holder. HOMIER came to town and had a trim router for $9.99! So I bought 5 and am goint to be like Norm--I won't change bits, I will change routers!. For what I do they seem to have plenty of power and at that price if one fails I will just chuck it.
Dave

[Madclicker]

I have used 5 of those trim routers for well over a year and they all still run well. It IS nice not changing bits. Now I need a few more stationary router tables...

[edsager]

Does anyone have a feel for the precision of gas pipe? What kind of tolerances can I achieve on a CNC table with gas pipe? Also, how would one test for the straightness of a pipe, say over an 8 foot lenth?

[coleasterling]

I don't really get why people use gas pipe. Do you just not have a metal yard anywhere around you? Pipe in any wall thickness you want is abundant.

[edsager]

Fair enough, but the question remains with any pipe, how do I tell if it is round and straight and what to what tolerance is it straight and round. If I buy at a scrap yard, how will I know if it is out of round by 0.005 or 0.05?

[coleasterling]

That, sir, I can't tell you. Hopefully someone more knowlegable than I will chime in with the answer.

[beone]

If you use a properly constructed torsion box the straightness of the pipe is not overly important since it will conform to the beds in the box. Check the pipe or conduit (I always use new) for dents etc. then check for straightness with a straight edge or plate(the top of most table saws is pretty good, a level with a machined edge is very good) My machine seems to be accurate to 5 or 10 thou. More than adequate for most any woodworking. I also use my machine to machine wax for use as foundry patterns for small things like keychains- the bit is more important, must be sharp and pointy but does letters less than 1/8 very well.

[beone]

a picture of the wax pattern