New Build Log ... 2440 X 1220 X 300

[EddyCurrent]

Just upload jpeg snapshots of the drawings from whatever software you use.

[Wobblybootie]

First Draft.



Gantry to fit on 20mm rails atop the frame. Z travel needed 350mm

[EddyCurrent]

I think you would be better with something on these lines.
http://www.mycncuk.com/threads/6565-...4294#post54294

You don't need a back in it and your top beams are not suitable for carrying the X rails due to the legs coming up through.
If you notice, my top beams are bolted to the frame, this allows for shimming to get it within a gnats knacks, ready for the epoxy.

[JAZZCNC]

No very difficult to build that way and too weak in key areas. Not enough bracing at bottom and the top rails will be very hard to get on same plane.
Look at this and Work along the same lines as this with regards bracing etc but without the adjustable bed if not required with slightly lower sides and you won't go far wrong.

This machine is in progress and will have 4th axis on the end when it's finished.

Also Why 350mm Z axis travel.? That is quite a lot and if your planning on cutting anything hard you'll get lots of flex and resonance giving a poor finish.

Edit: Opp's Eddy beat me too it.!!. . . or like Eddy's done. . Lol

[Wobblybootie]

Why 350mm? Because the whole idea of building the machine is it to perform two tasks, firstly to cut forms from 18mm Birch Ply and then when the forms are assembled by stacking one on top of the other to mill to the final shape. If I cannot have 350 mm of cutting depth I am throwing money away.



I was hoping to be able to store ply sheets ( I buy 10 at a time) under the bed. However with all the triangular bracing everywhere that also appears to be a No No ... Oh well back to the drawing board.

[EddyCurrent]

For some reason, after reading you're other thread, I had it in my mind you were laminating at 90 deg. to that shown in the photo.
It's okay milling to 350mm depth but what length cutting tool do you envisage using ? you don't want the spindle crashing into the job.

[JAZZCNC]

Ok well in this case then you'll be ok to some degree because the roughing of the forms doesn't require any decent finish and the 3D tool paths will be small step overs so very little tool pressure. Just build the Z axis strong with a good design and you'll be ok.

Regards the Bracing then it will still be possible to store sheets under with a few tweaks here and there so not a big deal.

[Wobblybootie]

I'm sure I said fore and aft ... nose to tail anyway now you see the size of the profiles that are cut.

Typical Forums ... lol ... Half say no need for Epoxy on a machine cutting wood ... the other half say it's absolutely necessary.

The Legs didn't come through the tops!! 'capped' they would have been flush ... I hadn't planned running the rails across them anyway. Thinking about it they could have been raised at the back to provide hard stops and mounting limit switches.

[EddyCurrent]

Typical Forums ... lol ... Half say no need for Epoxy on a machine cutting wood ... the other half say it's absolutely necessary.

This is for you to decide.

[Wobblybootie]

you poured your epoxy in small sections ... how did you get them any more level than the posts they were poured on already were?