Re: Gantry Aluminium thickness guidance
Quote:
Originally Posted by
MikeyC38
Hi Nick
As others have said, you do need to be more specific which you have done by showing details of your build and what you intend to cut. Rigidity is your best friend for any cnc build and as others have said plates across the end of the long axis will stiffen the frame significantly. In my build
here I used 80 x 40 heavy gauge extrusions ( 4kgm+) with 15mm 6082 T6 plates either end. The gantry sides are 20mm 6082 T6 water jet cut with heavy gauge 80 x 40 extrusion for the (short) y-axis. I am very pleased with the overall rigidity but will reserve judgement until I do my first cuts on metal. It might appear over engineered but I took the advice offered on the forum and I'm confident the machine will deliver the levels of accuracy I need. The use case for my machine is cutting balsa, hardwoods and aluminium at reasonable speeds, hence the robustness of the construction for the most difficult use case (cutting aluminium).
Hope this helps
Mike
Thanks mike - 1 question,
Your gantry sides are 20mm - these are the largest plate connecting the Y and X axis, where did you use the 15mm plate for?
Any did you use plate for the Z / X axis.
I have also used high grade extrusion, the bare weight of the aluminium along for me was 76 kg. I think the Y axis was 9 kg/m, and the X axis around 5-6.
Re: Gantry Aluminium thickness guidance
Quote:
Originally Posted by
dachopper
Thanks mike - 1 question,
Your gantry sides are 20mm - these are the largest plate connecting the Y and X axis, where did you use the 15mm plate for?
Any did you use plate for the Z / X axis.
I have also used high grade extrusion, the bare weight of the aluminium along for me was 76 kg. I think the Y axis was 9 kg/m, and the X axis around 5-6.
Hi Nick
I used 15mm plate at either end of the long extrusions (x-axis) (see my build log photos for the bed construction). For the Z axis construction I used 20mm 5083 cast and machined toolplate. It has a very fine and accurate surface finish which is critical for the setup and accuracy of that axis.
Regards
Mike
Re: Gantry Aluminium thickness guidance
Quote:
Originally Posted by
MikeyC38
Hi Nick
I used 15mm plate at either end of the long extrusions (x-axis) (see my build log photos for the bed construction). For the Z axis construction I used 20mm 5083 cast and machined toolplate. It has a very fine and accurate surface finish which is critical for the setup and accuracy of that axis.
Regards
Mike
I'm trying to CAD up another concept, but Fusion360 is down on my laptop !
Re: Gantry Aluminium thickness guidance
Quote:
Originally Posted by
dachopper
Good point - any tips?
I can do it up before installing, but that will be loaded with alignment danger
I could install a horizontal shelf over the top of it, rotate the flat face 90 so it points up, and do it up from the top instead of on the side?
I did the same as you, only I'd built it hence how I know!! I bought two of these style for mine and they're great.
Re: Gantry Aluminium thickness guidance
44 Pounds !!!!!!!!!!!!!!!!!!!!!!!!!!!! wtf, is that hand cnc'd or something !
I think I will make a horizontal plate, that protrudes over the top of the housing, and just rotate it 90 degrees, bolt from above.
I have spare 13mm plate around, so job done
Re: Gantry Aluminium thickness guidance
Quote:
Originally Posted by
dachopper
44 Pounds !!!!!!!!!!!!!!!!!!!!!!!!!!!! wtf, is that hand cnc'd or something !
I think I will make a horizontal plate, that protrudes over the top of the housing, and just rotate it 90 degrees, bolt from above.
I have spare 13mm plate around, so job done
I did say that style....you can get them much cheaper if you buy the Chinese made ones on eBay or Aliexpress...:)
Sent from my HUAWEI VNS-L31 using Tapatalk
2 Attachment(s)
Re: Gantry Aluminium thickness guidance
Ok guys - here is my final design
20mm thick
May put gussets over the ballscrew attachment, but Ill wait and see how rigid it is without
Nick
Attachment 19987
Attachment 19988
1 Attachment(s)
Re: Gantry Aluminium thickness guidance
So it was a busy Christmass
Went with 20mm thick
What do you think?
Attachment 20133
Re: Gantry Aluminium thickness guidance
Quote:
Originally Posted by
dachopper
So it was a busy Christmass
Went with 20mm thick
What do you think?
Attachment 20133
Hi Nick
You have been busy! so have I, finally got my machine cutting. Anyway the 20mm plate on the gantry sides will give stiffness in the Y/Z plane. BTW I noticed on your Z-axis plate the bolts are raised. You should counter bore these so that the trucks for your Z axis will have some where to be located. Remember Jazz's comments about mounting the rails on the back of the plate which holds the spindle and the trucks and ballscrew get fitted to the plate as shown in your photo.
All the best and have a successfull 2017!
Regards
Mike
Re: Gantry Aluminium thickness guidance
Quote:
Originally Posted by
MikeyC38
Hi Nick
You have been busy! so have I, finally got my machine cutting. Anyway the 20mm plate on the gantry sides will give stiffness in the Y/Z plane. BTW I noticed on your Z-axis plate the bolts are raised. You should counter bore these so that the trucks for your Z axis will have some where to be located. Remember Jazz's comments about mounting the rails on the back of the plate which holds the spindle and the trucks and ballscrew get fitted to the plate as shown in your photo.
All the best and have a successfull 2017!
Regards
Mike
Yeah, thanks for that, I realized this as I was staring at it yesterday, will have to counter bore to even get cart to slide past the bolt head I think.
I've decided to go the other route and mount the rail on the sides of the plate pictured, and just have the cart on the back of the spindle.
