Steel tube build

[Boyan Silyavski]

100x100x3mmm tubes works best IMO as most simple the build and could be cut at home using Rage or normal saw. And yes, if you could find sth like 80x120mm even better. The ideal for the gantry is 200x80, but as no such 2x 100x100 or similar will be alright.

Better do the Z with the rails on the front plate and they to slide, not the bearings. makes a stronger Z. I would concentrate on the Z mainly and do the machine around it. As the machine is as strong as its weakest link, the Z is the weak spot most of the times.


Abot the feeds and the speeds:



Most of the time on a home diy machine there is no tool change, to save time, tools or babysitting the job. No toolchange= slower machining speeds. I would say that most of the machines do not need to move faster than 5000mm/min in real life.
For example normally my rapids are 1500mm/min and normally i machine wood at 1500mm/min

But there are cases where i have to make a production run. Say 300 pieces of something. And then i push the machine properly. Say if slow it will do the job for 12 min, when i push it it will do the job for 4 min. And that matters as it could save me a day or two. At these cases i am in the 7-8k mm min.

My machine can do 20k min.when servos at 3k rpm and even faster as my servos are 6k rpm rated , that is at 3k mm /sec acceleration. I have machined at 16k mm/min and while it makes me smile to see my baby move like a bullet shot from a gun that 250kg gantry, it starts to feel and look really Dangerous. The ball screws start to heat up, so i have to grease everything perfectly before hand. The biggest problem is cause wood starts to chip sometimes as its not perfect material like the plastic or similar. So at the end of the day my philosophy is : Less time i spend on the machine=The better , hence the slower speeds give me perfect finish and i spend less time on the machine. Now if i had ATC i would have pushed jobs using roughing bits, normal and then finishing passes, but as its not the case, i am happy..

So, nope. You don't need a fast machine . You need a precise machine that is free of vibrations and gives you perfect finish.

[JAZZCNC]

My machine can do 20k min.when servos at 3k rpm and even faster as my servos are 6k rpm rated , that is at 3k mm /sec acceleration. I have machined at 16k mm/min and while it makes me smile to see my baby move like a bullet shot from a gun that 250kg gantry, it starts to feel and look really Dangerous. The ball screws start to heat up, so i have to grease everything perfectly before hand. The biggest problem is cause wood starts to chip sometimes as its not perfect material like the plastic or similar. So at the end of the day my philosophy is : Less time i spend on the machine=The better , hence the slower speeds give me perfect finish and i spend less time on the machine. Now if i had ATC i would have pushed jobs using roughing bits, normal and then finishing passes, but as its not the case, i am happy..

So, nope. You don't need a fast machine . You need a precise machine that is free of vibrations and gives you perfect finish.

That's a crazy way to work. So your cutting wood at 1.5mtr/min when you could and should be cutting at 7mtr/min and causing excess tool wear just because you don't want to change the tool one time and do a finish pass. . . .A manual tool change takes 30seconds.!!

I cut aluminium faster than 1500mmm/min.!

[Boyan Silyavski]

That's a crazy way to work. So your cutting wood at 1.5mtr/min when you could and should be cutting at 7mtr/min and causing excess tool wear just because you don't want to change the tool one time and do a finish pass. . . .A manual tool change takes 30seconds.!!

I cut aluminium faster than 1500mmm/min.!

I guess realy depends on what kind of job i am doing. When i cut general stuff and cleaning passes yes i cut at 7-10k mm min, but when i am fabricating for example the music instruments i am making i keep slow, because going fast chips edges from time to time and is very difficult to repair if at all, as size must be correct. So i dont speed then and cut at finishing speeds. As at the end of 3-4 days work if i have chipped say every five from 100 pieces it would be like 50 pieces to repair. Which is tremendous amount of time lost and material, if its unrepairable.

Same with the signs i make. I aim at perfect cut of Plexiglass or Dibond. The other day i cut PLexiglass and made a video, even wanted to post it here. 18k. spindle speed and 70 ipm/ at 0.5mm deep using 1/8 single flute. I played like 3 hours to find the perfect ratio. basically went to the conclusion that could go 2 times as fast and 3 times as deep, but from time to time there was crap on the bit and i had to be constantly there. Having in mind had to cut 8 hours and the material is 100e/m2 i have decided to go at said speeds and air blow from the fog mister and that let me have the job unattended. So simple.


PS i cut aluminum at 2k mm min also

[JAZZCNC]

I guess realy depends on what kind of job i am doing. When i cut general stuff and cleaning passes yes i cut at 7-10k mm min, but when i am fabricating for example the music instruments i am making i keep slow, because going fast chips edges from time to time and is very difficult to repair if at all, as size must be correct. So i dont speed then and cut at finishing speeds. As at the end of 3-4 days work if i have chipped say every five from 100 pieces it would be like 50 pieces to repair. Which is tremendous amount of time lost and material, if its unrepairable.

Yes exactly, which was my point. That's the material dictating the feeds not you deciding to go slow. I'm sure if you could with same finish etc go faster, then you would.

End of the day it's mostly the material and tools that dictate the feeds n speeds required and not something the machine should dictate because it's under specified or poorly designed. Like wise the user's choice in feeds n speeds is limited to a small range if they want to cut correctly and not destroy tools or materials.