Sheet metal thickness

[Wild Russian]

Hi,
I have noted that all laser/water jet designs that I have seen - and Sayber OSG too - use sheet metal as thick as 3/8" - 1/2" (from 10 to 12,5 mm). Is it really necessary? I have thought that 1/4" is enough for dimensional stability of a frame... If the motor, pulley/sheave and another rolling parts are good balanced, vibrations must be very low?

[admin]

Yes the thickness is required for drilling and tapping holes for assembly. I used 10-32 machine screws to secure the mounts to the frame. These have to be drilled and tapped not into the face of the steel but into the ends.

Drill and tap into frame material

OSG_frame_mechanical_IMG_5333.jpg (78.78 KiB) Viewed 1902 times

If you wished to use smaller screws or weld the components, then yes 1/4" plate will be fine. Thinner material will have an effect on other assembled things like the tracking hinge and arm.

As a rule, the thickness of threaded material is equal to or more than the diameter of the bolt, so a 3/8" threaded hole should be at least 3/8" deep for proper thread engagement.

Dan

[Gavin_Hoole]

Can I use 10mm? what sort of material do you suggest? I am thinking of structural steel EN9 .

[admin]

Hi Gavin,

10 mm is very close to the 3/8" I used. Should't be a problem if you use 40 mm square tool arms You can stack 4 x 10 mm to make the receivers a close fit. You'll still need to have some shim in there to allow a small amount of play to slide the tool arm in and out.

The steel I used was A36. I believe E9 is medium carbon steel. I guess as long as you can drill and tap it. I'd go for anything that is common and easy to machine.

We still do not have a metric version with an IEC motor in mind, however someone is working on it at this time.

Edit: Craig posted his metric version here a few days ago: viewtopic.php?f=11&t=44

Dan