My new VMC project

[Jason3]

Hi everybody,

I've started a new project, and wanted to share it for anybody interested. It's a larger mill than all my previous builds, and is nearly as big as I think I can practically make in my workshop

I originally called this a Benchtop machine, but realistically it's a little bigger than that so I don't really know how to classify it. I'll have some wheels underneath so it can be moved around readily when necessary, so maybe it can be called the MobileVMC™

In contrast to my other CNC projects, this one is to be pretty much all steel. It'll use NSK ball screws, THK caged ball linear bearings, and brushless servo axis drives. I'd like to enclose it so I can use flood coolant when necessary and to keep the noise down as well.

Hopefully it'll be a decently capable machine when it's done. I'm certainly looking forward to a larger work envelope than my current baby CNC mills

Cheers,

Jason

Here's the first few parts:

[MrBean]

Very cool project. I shall certainly be following along.
What size work envelope would you say the mobile VMC will have, roughly?
I'm sure I won't be offering you advice during your build, but I'll make sure to shout Yeeeeee Haaaa!!!! and other such noises of encouragement, now and again from the sidelines

Really looking forward to this one. Thanks Jason.

Regards Terry.

[hesham morsy]

[henrikw]

I'll just add myself to the YeeeHaaa! choir

Always looking forward to your posts, very nice work!

Henrik

[LeeWay]

Have you got any video of it running yet?
I would love to have another mill myself.
I am looking for a used one to retrofit, but those are few and far between around here. I may wind up doing one in concrete or epoxy, though I really like the 80/20 for it's versatility.

I will stay tuned for a video even if I have to wait until tomorrow.

[sergizmo]

Yesss! That looks solid. What is the bar, 2.5" by 2.5"?

What do you have in mind for the spindle Jason?

[Starleper1]

Looks good so far. It looks like your choosing the path i did with my mill, as far as the table goes.

[Jason3]

Hi guys,

Terry, Hesham & Henrik - thank you for the encouragement! Cheering is always welcome and gladly received The work envelope will be 750 x 400 x 400 mm or so (30 x 16 x 16" roughly), just a bit more than my knee mill.

Lee - Oh no, no video! I better pick up the pace An Epoxy granite machine would be good - there's pretty few nice examples of scratch built EG machines here. I started a retrofit too, on my knee mill, but it's on hold waiting for some ball screws. Somehow I can't help myself, I always end up with another machine I simply must build, usually before the last one is finished

Sergizmo - close! That's 3" x 3" bar, except the servo/ball screw mount which is ex 4" square stock. For the spindle I'm ultimately looking for a BT30 taper, around maybe 4-5 Kw. 10Krpm would do, but more would be nice. I'd like to try making my own, so it may be that I'll put my Kavo spindle on this machine to get me started.

Starleper - there's some definite similarities to your mill! When you refer to the table, do you mean the work table or the machine stand?

Best regards,

Jason

[Starleper1]

I meant the way the table will be mounted.

[Teyber12]

Great luck! i have followed your lathe thread and am amazed at your talent to just make it come together so well... Keep up the good work, i was excited to see this thread title

[the4thseal]

teyber whats up with the avatar pic? curious.

[Jason3]

I'm telling myself: progress is progress, however small it may seem

This part (the longer one, on top in the photo) itself didn't take long, but I spent some time confirming that the big mill was staying flat throughout it's travel - I didn't want any dips in the rebates that the linear rails will mate with, for obvious reasons. The part is quite a bit longer than the travel of my knee mill, so I felt it was worth some care to get it as good as possible. I think it went ok.

Starleper - right, I see. Actually, I was a little concerned about rigidity with the linear bearing blocks being closer together on the X - on an industrial machine they would usually be further apart. However, this machine isn't going to have to handle hogging out 4340 steel with a 20 Hp spindle, so I think it will be ok - I'll take the extra travel for now. I will do some measurements though, and if I find it is deflecting more than I expect, I will have an extra set of holes spaced further apart in the table carrier - I can just shift the bearings out and increase the stiffness at the cost of some X axis travel with no other changes.

Teyber - thank you for the encouragement!

Best regards,

Jason