cnc router

[jc286006]

hi all
im new to this site and have been looking though it extensively i have a question about the pipe that you use for your axis rails i have read that it is black gas pipe is this the schedule 40 type or are you using the schedule 80 type ? im thinking of building a gantry style similar to the jrgo style that plans are available here and have purchased a set of the phoenix plans from john klienbauer. i plan on doing the nessesary mods to make it to the length that i need somewhere in the area of 24"x48 " cutting area. also im using aluminum instead of mdf except for the cutting surface. if you use schedule 40 pipe on the plans wouldnt schedule 80 be better suited for the axis rails even on a smaller machine? this pipe is available in my area for $1.38 a foot which i feel is a reasonable price to avoid any problems with the x axis bowing from the weight of the gantry moving acrossed it please give me your opinions on this idea. thanks james

[ger21]

The only way to avoid the axis bowing is to support the pipe along it's length. I doubt you'll see mauch difference between the two pipes.

[fyffe555]

The difference between Schedule 40 and 80 is the rated pressure - not its mechanical strength. 80 can handle higher pressures by being slightly thicker in wall thickness and so will weigh slightly more - 1" schedule 40 is around 1.7lbs ft, schedule 80 around 2lbs ft. There's a marginal increase in cross section so there's almost no benefit in ability to bear load or in resistance to deflection.

Before you go spending lots of cash on an Aluminium Pheonix in 24"x48" look to see what the designer says about increasing the size.

This design - without major reworking - will not work well in 24"x48". You'll need significantly increased size of tube, support it along its length, more ridgid tube end supports, different lead screw sizing, bigger motors.

The free design(s) here would be a better starting point. Spend some time looking at the designs others have built here.

What are you planning to cut with it? The as designed pheonix can cut soft materials only..

Andrew

[jc286006]

i am planning on cutting balsa wood and 1/4 aircraft ply is it. but i want to be able to cut a fairly large number pieces at one time thats why i am wanting some thing in the area of a 24x 48 cutting surface. thanks for the info on the pipe,one thing that i think will be a plus by using it is the fact that the thicker wall will make it easier to drill and tap for adding the supports what are your feelings on using square tube in the place of pipe would it be any stronger?

[rweatherly]

Sch 80 pipe has a deflection that is about 17% less than sch 40. The biggest advantage is that most of the sch 40 has a welded seam, while the 80 is normally seamless, so you may be getting pipe with a more consistant diameter with sch 80.

[joecnc2006]

you can look at my thread i did the mod to a larger machine..

Joes 2nd Machine

Joe

[jc286006]

hi joe i looked at your thread after posting this one what size steppers are you using on your machine ?

[joecnc2006]

right now i use the HP motors 5.2v 1.4a 100oz, and cut an average of 30ipm, but i purchased the hobbycnc kit with the 3v 3a 200oz motors i just have not got a chance to build another machine to run them on, so i can have two running at one time.

Joe

[woodworker2]

Nice looking machine! What do you anticipate you can cut with it? Just wood or can you cut aluminum or steel with it?

[joecnc2006]

Have not tried to cut alumn, I cut wood, and HDPE right now with it. Like to see what jc286006 comes up with...

[jc286006]

hi all ive been real busy the last couple of days working on my first machine im going joes route building one with mdf to use as a design platform and learning experience for bigger and better later! i ordered the 200 oz-in steppers and driver card from hobby cnc i should be recieving them tomorrow or thursday i have all the parts cut drilled and started tapping for the first model which will be a copy of the jrgo machine from the plans here. except i will be using a frame of channel iron and aluminum angle i managed to scrouge at the local recycling company. i`ve read quite a few people have been buying aluminum on e-bay, check for recycling centers near you i got all the aluminum angle and plate that i think i`ll need for a $1 a pound. i`ll try and post a few pics tomorrow if i can break myself away from the fun im having building this thing, i can hardly wait to fire it up LOL!!! later james