Sturdy and Fast all Steel CNC , my first build

[Boyan Silyavski]

Thanks for the advice. I just came from the metal shop, but they still have not cut it. However the profile seemed normal squarish, nothing unusual, so i believe that will not be a problem.

I wonder guys what are you constructing with 100x100x10 ?

[JAZZCNC]

I wonder guys what are you constructing with 100x100x10 ?

My case It's actually 200x100x10 with front face ground for rails and it will be Fixed gantry for my new DIY-VMC .!!!

[IanS1]

My case It's actually 200x100x10 with front face ground for rails and it will be Fixed gantry for my new DIY-VMC .!!!

Are you taking orders for it yet?

[HoGo]

I wonder guys what are you constructing with 100x100x10 ?

This:

Actually the table and gantry are welded and waiting for milling for rails. So far we are at roughly 400kg, finished machine will be just hair under 600kgs.
Adrian

[Boyan Silyavski]

This:

Actually the table and gantry are welded and waiting for milling for rails. So far we are at roughly 400kg, finished machine will be just hair under 600kgs.
Adrian

Hi Adrian,
i couldn't help but notice, your gantry is only supported by 1 side plates at each end? Wouldn't it need something stronger, like my design? As profile like support at the sides is stronger from even a thick plate i believe. There is a calculator Excel sheet somewhere here on the forum.

Your table structure looks great, and i have given a lot of thought how to make gantry similar to yours, it looks great also.

[HoGo]

The gantry sits directly on the 20mm plates that will hold the rotary nuts, to which another 22mm thick plates with cars will be mounted. There's no gap there. The sides are 12mm thick steel. So there is direct contact of bottom of gantry ends to rail cars. There is no measurable side to side movement possible other than any play in the rails/cars.
I used 100x100x10 SHS for most of the construction as I had to order two 6m lengths and didn't want to throw away too much. Also one 6m length of 140x80x7 was used for gantry and for two table supports, all was used up almost without waste (supports intentionally placed along the table to create space for extra long 4th axis as we'd like to make some gunstocks in the future).
Adrian

[Boyan Silyavski]

The gantry sits directly on the 20mm plates that will hold the rotary nuts, to which another 22mm thick plates with cars will be mounted. There's no gap there. The sides are 12mm thick steel. So there is direct contact of bottom of gantry ends to rail cars. There is no measurable side to side movement possible other than any play in the rails/cars.
I used 100x100x10 SHS for most of the construction as I had to order two 6m lengths and didn't want to throw away too much. Also one 6m length of 140x80x7 was used for gantry and for two table supports, all was used up almost without waste (supports intentionally placed along the table to create space for extra long 4th axis as we'd like to make some gunstocks in the future).
Adrian

Thanks Adrian! Now i get it. Its not raised. Same with me. Have to think in 6m lengths :-) .

[HoGo]

I just realised the pics I posted were somewhat outdated. In the final version I moved the tabs holding rotating nuts/servos of X axis to the rear and turned them 180 degrees so the pulleys are just at the rear plane of gantry. This was done to make possible to add another pulleys so I can belt the two sides together with one long belt. There are schools of thought (especially on our local CNC forum) that they'd better be tied together so if one side will stall or not work properly the gantry won't damage the rails. I believe that this is not necessary as servos have quite reliable feedback and one stepper just wouldn't have enough torgue to damage rails and the other side will stall within few steps from the first side.

[Boyan Silyavski]

I just realised the pics I posted were somewhat outdated. In the final version I moved the tabs holding rotating nuts/servos of X axis to the rear and turned them 180 degrees so the pulleys are just at the rear plane of gantry. This was done to make possible to add another pulleys so I can belt the two sides together with one long belt. There are schools of thought (especially on our local CNC forum) that they'd better be tied together so if one side will stall or not work properly the gantry won't damage the rails. I believe that this is not necessary as servos have quite reliable feedback and one stepper just wouldn't have enough torgue to damage rails and the other side will stall within few steps from the first side.

I believe the same. Moreover i believe this belt being so long is not a good idea if the expectation is to route aluminum, but that's me. I have a small belt driven machine and on it have the motor steps adjusted for wood and for aluminum differently, to compensate belt stretch. Dont know how that be if using big fat belt 25mm wide. Maybe will not stretch if pre loaded/pre tightened correctly.

Anyways the steppers just stall. Who knows what can happen with servos if stalled, i have no idea. Still not in that league.