This is just a thought experiment - I don’t have a need for this per se.
The 4x8 Altmill has roughly 3 extra inches of Z clearance compared to the 4x4 version. I’m wondering if it would be possible to CNC new Y-axis gantry plates that have an extra inch or two of clearance to improve the capabilities of my 4x4.
Now that I mention it, I wonder if the bolt pattern is the same between the 4x8 and the 4x4. If the 4x4 is sufficiently rigid, could we buy the Y-axis gantry plates for the 4x8 and install them?
Raising the height of the cross rail is one thing but wouldn’t you also need to increase the z rail travel range?
It would be nice to increase the Z clearance and 3" seems like a nice amount that shouldn’t affect rigidity by a lot.
@keglin One thing to consider in your experiment is that, if you simply raise the Y rails to get more Z clearance, you may well have issues with trying to cut through material. End mills are only so long. I raised the Y rails on my LM Mk1 to get more clearance above the Vortex. The downside is that I now need to add a second spoilboard under “normal” thickness material if I want to cut through it with a 1/8" end mill. I think that’s a reasonable tradeoff, but it can be a bit inconvenient.
That’s what I’m thinking I’ll do. I’m more often limited by the clearance of the gantry than I am limited by the length of my endmills. But if I’m in a situation where that matters, I’ll just chuck on another spoilboard or two
When and I think it is out the taller Y plates and the stiffing gusset are out in the CAD files for the 4X8 machine. I would like to do this so I can use my A-axis to its fullest. I was hoping to just buy these parts in the future. Maybe if enough of us bug the guys this will be offered as an upgrade kit in the future. I would prefer to get the nice black look that I currently have! As to needing to change the Z on my MK2 I have more than enough travel on it to handle the added height and my longer 2.2KW spindle helps as well. Note that the MK1s gantries do not have the T nut slot on the underside so the gussets bolts would require that a holes bored and would need to be tapped or so I have been told. If they don’t offer this we can pull the files and mill out our own plates and gussets on our current machines!
I added 1" to the Y Axis Gantry Plates in Fusion and then uploaded that to SCS and if you order 10 of each side its about $300 per plate so $600 per machine.
The more qty you order the better the price gets per part.
Only if you have a LOT of heavy timber to deal with.
For one extra inch you could just pull the 3/4" spoil board and replace the 3/4 inch (usually) main board with a 1/2" board.
For a one-of, if your project fits in between the mill cross rails, you could probably make some sort of temporary surface below the cross member level.
Not gonna lie, had to look that word up and still not entirely sure I understand it
But if I understand the word like I believe I do, I selected the perfect point in the plate to add the extra that only moves the Z vertically, it does not shift the tram +/- in the Y axis.
sorry about that. I might have used it wrong. But basically what i was asking is what is the maximum addition you can do without introducing flex, loosing ridgitity and having them to beef up X gantry, use gussets and redesigning the entire altmill lol.
I asked support about the 4x8 plates and this was the response.
“You can’t use the 4x8 plates on the 4x4, they are completely different as they use a rack and pinion system and the motors are mounted on the plates for the Y axis.”
thats a good point. I have a feeling they are working on mk3 version that will have more travel to accomodate atc racks and possibly higher Z but its tempting to try out your option as well.
I have toyed with the idea of adding 1 more inch to the Y plates just so I don’t have to keep retramming my spindle after I take on and off the vortex. If only I had a 2nd machine to toy with.
