welding steel base or just getting aluminium extrusion

[Neale]

Was just a thought after watching that video, i know i will be needing straight edges and engineer squares but most of these videos on youtube are just some guy pointing his camera at an engineer square and going up and down which lasts 20 seconds long lol. i am still reading on here and watching other people tips and tricks but all i can picture in my head is getting one rail on and have it as straight as possible on one side and bolt it down and then use the gantry to slide up and down to get the second rail inline and then bolt that down and then just use engineer squares against the aluminium beam and side plates to make sure thats square

You are going to need to be able to square the gantry once the machine is up and running, by adjusting home positions for each end of the gantry. Whether you do that via software or manually (home one end as part of the usual homing sequence and then adjust the second end manually) doesn't really matter but you do need to be able to do this. Probably the easiest and most accurate way to check that the gantry is square is to use the machine to make four holes in a square pattern in a piece of suitable material (I use MDF and make the holes a firm fit for the shanks of a set of identical drills). Measure the diagonals and adjust the home positions for the gantry until those measurements are as close to each other as you can make them. Any machine which uses two motors/ballscrews on a single axis will need to be able to do this.

[reefy86]

Hope you all have a good Christmas guy's

[reefy86]

is it possible to combine a 4th axis capable of cutting up to 200x200mm to my design? i am struggling to figure out how i would without having to adjust the z height, my plan was to adjust the width of the machine to allow me do add a t track to the side of the machine which does not affect the spoil board so i can adjust the 4th axis length so maximum cutting for the 4th axis would be 2400mmx200mmx200mm. So far my z height already has a cutting height of 200mm so if i was to somehow add the 4th axis i feel as if i would now need to adjust my z height to around 300mm and i have no idea how weak it would make my z axis doing this.

[Desertboy]

http://www.chinasavvy.com/tolerances...tnessroughness

[EddyCurrent]

What about this idea; https://www.cnccookbook.com/wp-conte...atheAttach.jpg
or put it at the end in a smiliar manner.

[reefy86]

Thanks eddy :)

[Boyan Silyavski]

Just responded you to the PM, but now i see here where you are going with that. There is absolutely NO NEED for the spindle to extend below the table bed in order to achieve good 4rth axis

Meaning that the centerline of the round object could be level on with your bed. And the Z gantry clearance will be your object max radius. Add 10cm for the bit and chuck. There should be your spindle in upmost position. i recommend boxing the spindle like on mine machine and making tha gantry a bit wider in vertical. So more or less a normal machine without too much mods except for strong Z. thats it

[cropwell]

I recall a build by KingCreaky that had a removeable bed that allowed a 4th axis to bolt in (can't find the thread though).