[Stevie]

Or Maybe Just Hidding A Very Messy Garage

[MaxLogan]

Stevie,

Fantastic work mate.
I'll be following your progress closly as im interested in a very similar setup. I would like to add a 4th and 5th axis also, just to complicate things a bit more, lol.
Keep up the good work.

[Stevie]

Mine will be 5 axis too
Just not sure on the design of the 5th yet; 4th will be rotary

I like the HASS cradle design with the 4th centered in the cradle
This lowers the 4th; and makes programming a bit easier

[MaxLogan]

Stevie,

Awsome....I'll through down some CAD designs for the 4th and 5th axis and post them...we can bounce ides off eachother......i can also email u some stuff

[pstockley]

Looking good steve. What are your intending machining with it?

[JFettig]

I like the cradle, but one I really like to see in action is a tilt and swivel head. In reality if you know your 3d vectors and all you could program one of those by hand, all your drilling and whatnot. If you can get the angle, or start and end or many other ways, you got a vector in I, J and K and swivel the head in c and b directions to the angle.
One thing that might be hard to calculate for movements is tool offset from the axis of rotation.

I was thinking that if I had the cash at the time I actually get around to building my mill, I would buy an extra rotary table and throw it on behind the head and have a tilting b axis then I could throw a rotary table on for the a-axis.

Jon

[CATCH22]

I Was Over At Steves Place Checking Out The New Mill, This Thing Is Awesome,it Is Also Huge. Just Wanted To Say Good Job Steve. Cant Wait To See It Cut Something,and When I Say Something, I Mean Something Really Big!

[Stevie]

Looking good steve. What are your intending machining with it?

I don't have any intentions of machining steel; I do that enough at work; my home stuff is more for the softer things in life LOL


Thanks Catch
I'll need you to help me lift it off; to do those changes we talked about

[pstockley]

I wasn't implying it wasn't up to the job. Just curious what you had planed for it. I know you are interested in naval stuff, are you planing on milling hulls on it?

[Stevie]

. I know you are interested in naval stuff, are you planing on milling hulls on it?

Exactly

I did not take offence; all my home stuff is for none ferrus materials

[CNCfun&games]

I like your robust design! I built a similar configuration with 3/4" x 8 " x 24" CRS uprights & a 3/8" x 3"x 6" rectangular tube spreader and it is Rock solid. It has the same travel as my B'port 2J but it is much more convenient to use with a 1" x 12" x 18" Aluminum table. You will also appreciate hiding your linears & ballscrews. On my next design I'm going to inc. PStockley's idea of using a Granite surface plate as a base. I'm temporarily (5 yrs) using a die Grinder for a spindle and it has worked out well! Enclosed is a picture. Will Smith Mission Viejo, CA

[Stevie]

if you chk my thread on the mini mill; you'll see i do like to cover everything up

[Stevie]

Well after placing the Gantry on the steel support; something came to light
I don't think I can fit a mill with just short of 8ft of travel in my garage; I can't take over the old ladies side of the place; so I guess the next machine will be scaled back
Me and Catch talked about this last time he was over!!

The Gantry is now 80" tall with Z at max up
This did provide for an interesting experiment
I mag'ed my DTI to the steel beam in the garage; and put the tip on the rail of Z
standing on the steel support (remember the bed is not bolted to the frame yet) I could move the Z by pushing about 0.03"
I then talked with Catch; it seemed a diagonal cross brace would solve this; they will run from the vertical legs to the steel base; as this will be bolted soon; this should complete a triangle and stop the deflection
Really 200lbs pushing on Z at max travel 0.03 is not bad; the bridge is only on with 2 screws per leg and is flexing for sure' plus I'm sure I was moving the base from the steel support a bit
with a 27lb 3/4 hp 3 phase and the Nema34 stepper plus the spindle with it's supports/brgs I think the head will not be moving too easily in deflection; also the rotation point of the deflection will be 1.5" below the table not at the top of the machine as per this experiment; the cutter will be about 30" below the point measured so I think it will not present a problem at all; but the braces will put my mind at ease; I have some nice 4130 AC grade tube for the braces

[Stevie]

Ok lets get back to the build
Here is the X stepper with it's new mount
The stepper will hang down under the channel that joins the 3 x 3 box beams
Also in the shot is the bed/table assemble upside down; the access holes for the THK 35mm rail blocks can be seen


Top of the shot is the base frame witha final coat of black enamel to stop rust etc
I was back in the shop this morning welding the 7/16th nuts on for leveling bolts; I also added the mounts of the diagonal braces mentioned earlier
Once the paint is dry and my wife clears her SUV from the other bay I'll snap a few more shots

[Stevie]

Frame finished paint is still a bit wet

another view

now with base and X attached; the 7/16" bolts worked great to level it in both directions; it's now level

[Stevie]

Finished the x stepper drive mounting today; still need 2 washers for the adjust slots
That small pulley is not for tensioning; but is a wrap angle increaser
I like to ensure as many teeth are involved as I can get; i did have a timing belt snap over once due to lack of wrap

[KTP]

Dang Stevie, that is one huge slab of aluminum!

What do you do for thrust bearings on your ballscrew? (sorry if I missed a post on this earlier in the thread)

I want to make a large gantry mill soon (so my wife will not keep trying to cut large sheets of plywood on my Shizouka bedmill) and am not sure what lengths to go to on the ballscrew mounts. My mill will be designed around scavenged parts. I got lucky with a 2 inch diameter 9 foot long ground ballscrew and nut, brand new for $125 and 6 sets of 9 foot long 2 inch wide THK rails with 2 carriages per rail, brand new for $50 each...monster rails...they weigh like 100+lbs each....really too big, but oh well.

Anyway, following your design with interest!

[Stevie]

Hi Rick

Well there are angular brgs for all the ball screws; plus i have 2 reg rsr brgs on the none drive end
The ball screw is 10mm pitch for X and 20mm pitch for the Y-Z so 2-1 ratio on X and 4-1 on Y-Z
I want a 5mm advance for 1 rev of the stepper

The Slab is the first part I have had to buy as far as materials goes that was cut for me and not scrap (I do pay for the scrap) the slab was $400

[JavaDog]

Wow Stevie, this thing is going to be a monster when you get it finished.

That's pretty interesting about the wrap angle increaser, haven't seen that before - going to have to remember that when I order all my pulleys/belts for my machine. How did you plan/measure for the extra length?

[Stevie]

trial and error
I just hung the motor down on the belt i had and sorta guessed at the lenght of the plate