Thor, or should that be Zeus?

[Tom J]

This works the same with say 22x15 aggregate but they grade it down using smaller and smaller aggregate down to ash.
I am looking at building a concrete mill with Dean's help using this method. We shall see.

its good for heavy work like milling in steel where damping vibration is important. Technically should be easier to build, considering your planes are smooth, even, leveled, squared etc.
All mounting surfaced for rails, bearings etc can be prepared - machined and than fix to the mold by precise adjustment before mix is filled in. That is how I would do and will in one day.

[Clive S]

All mounting surfaced for rails, bearings etc can be prepared - machined and than fix to the mold by precise adjustment before mix is filled in. That is how I would do and will in one day.

Done on one of these

[needleworks]

I can't believe I just found this thread ! About four or five weeks ago a friend of mine sent me a link to a machine that he was considering, very similar to the machine you are building ! The only thing that concerned him was the fact that it would be coming from foreign shores, (vat, customs charges, shipping etc) I must point him towards this thread and see what he makes of it. Anyway, here is the machine he was considering, as you will see, the similarities are there

http://www.ebay.co.uk/itm/CNC-Millin...p2056016.l4276

[Chaz]

I can't believe I just found this thread ! About four or five weeks ago a friend of mine sent me a link to a machine that he was considering, very similar to the machine you are building ! The only thing that concerned him was the fact that it would be coming from foreign shores, (vat, customs charges, shipping etc) I must point him towards this thread and see what he makes of it. Anyway, here is the machine he was considering, as you will see, the similarities are there

http://www.ebay.co.uk/itm/CNC-Millin...p2056016.l4276

Ive seen those machines. Looks 'nice'. Similar idea, certainly, nothing really new with a fixed gantry idea.

That machine is ex Austria so no import tax etc. It's a fair bit smaller / lighter than my machine. Probably worth a look at that price (compared to say the Chinese imports).

Here's a vid of it cutting - https://www.youtube.com/watch?v=oSO0BlGFaqA . The one on sale only as a 2.2KW spindle, the one in the video is almost 4KW.

[Tom J]

Done on one of these

I have cast iron one 275kg. This help me a lot with my welding

[Davek0974]

These lovely welding benches :)

How do you keep spatter off of them?

[Clive S]

Dave the one I linked to is 150mm granite so the splatter does not stick

[Chaz]

I need to finalise the location of the gantry. From what I can see, the 'best' location for the spindle centre line is the middle of the machine. Keep in mind that once the gantry is fixed, its fixed.

Any reason I would not have it in the middle of the machine? The table pretty much moves the full distance of the table, except around 30mm to the rear which is where the ballscrew bearing holder is.

I could play around with table sizes, considering having a tool rack if I go with BT30 and like the Datron machines (but they are moving gantry) have tools mounted on the rear of the table for the ATC. Most of the machine images I can see online seem to feature the spindle generally in the centre of the table length.

[JAZZCNC]

Bring table to front of machine then spindle line is on or just past the inside edge of table. Allow for largest tool diameter if want to get maximum cut out of it and have travel for it.!

To be honest Chaz your wide open to world of pain if you haven't at least drawn this out on paper. Just basic Cad model will highlight any potential clashes. So many Gotcha's waiting to bite I wouldn't dream of building without basic model. Will save you time and money in long run because often these Gotcha's bite after it's too late or major hassle to change.!!

[Davek0974]

Second what JazzCNC said, even a dimensioned 'fag-packet" sketch will highlight important bits that (and have) goofed up a machine build ;)