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giladv
24-07-2017, 04:40 AM
Hello everyone,

My name is Gilad, i'm 30 and i work as a software engineer.
for the past 6 months or so iv'e been working on this project mainly for educational purposes.
the machine was designed to mill hard and soft metals while being light and graceful enough to be run in my apartment:)

Technical stuff
- 20mm Hiwin linear rails on all axis
- 20mm/10mm pitch C7 grade ballscrews and bearings on all axis
- machined parts (incl the base) will be Al 7075 T6
- milling head: 8000rpm ATC BT30 90mm spindle, 1.8kw AC servo
- Y axis Al profiles are Item's 120X120mm heavy variant
- X axis Al profile is item's 160X80mm heavy variant
- gantry and side profiles will be filled with epoxy granite
- motion servo's X4 nema34 clearpath servo (CPM-SDSK-3421P-ELN)
- max travel 800X330X290mm

i'm gonna keep this thread updated with the latest images and videos of the build so stay tuned.

the machine:
222732227522274
22280

22276222772227822279222812228222283

Lee Roberts
24-07-2017, 10:39 AM
i'm gonna keep this thread updated with the latest images and videos of the build so stay tuned.

Deal :thumsup:

Clive S
24-07-2017, 11:19 AM
Hi Gilad and welcome to the the forum, It looks a nice project. How about a link to the spindle? I will be following with interest :thumsup:

giladv
24-07-2017, 11:23 AM
thanks!
it's skyfire's BT30
http://skyfirecnc.com/picshow2.asp?id=14

A_Camera
24-07-2017, 12:17 PM
the machine:

22280


Hi,

I am sure it's going to be a nice machine but based on my experience I'd suggest making some changes before it's too late.

My frame was originally similar to yours but I had to remove those wheels because of shaking caused by the G-forces. A fast machine with heavy gantry and Z movements will generate far too much shaking even if all the four wheels are locked. I changed my design, moved the wheels and the machine is now lowered to the floor on four wooden blocks, efficiently reducing vibrations and shaking. The wheels are still there but they don't touch the floor and gets lowered when the machine needs to be moved.

I assume your machine is going to be much faster than mine, considering you are using servos, so it would be a shame if you had to lower the speed and acceleration just to prevent the violent shake, so consider this before it is too late.

giladv
24-07-2017, 12:37 PM
@A_Camera, you are absolutely right, also i wouldn't be able to level the machine with the wheels.
i thought about a hybrid solution of using 2 wheels at the back and 2 anti-vibration legs at the front for stability.
there will also be corner brackets all around.

could you share an image of your solution?

thanks!

giladv
24-07-2017, 12:39 PM
hi Clive, thanks!
i used the BT30 spindle from skyfire
http://skyfirecnc.com/picshow2.asp?id=14

A_Camera
24-07-2017, 08:44 PM
@A_Camera, you are absolutely right, also i wouldn't be able to level the machine with the wheels.
i thought about a hybrid solution of using 2 wheels at the back and 2 anti-vibration legs at the front for stability.
there will also be corner brackets all around.

could you share an image of your solution?

thanks!

22288

There is really nothing to show. The machine is resting on four wooden blocks and the wheel is suspended by about a millimetre or two. If I need to move the machine I lift one end, remove two of the blocks, lower on the wheels and do the same for the other two feet. This gives me enough clearance to move it around. I think four steady feet is better than two with wheels.

routercnc
25-07-2017, 08:06 AM
Nice work so far. Can you show the detail behind the Z axis top covers. I'm guessing servo drive via belt to the top of the ATC spindle pulley?

Also, are the gantry ends just covers, or machined from solid (!)

I've looked at that skyfire spindle many times before and been very tempted. Let us know how you get on with it.

Chaz
25-07-2017, 01:00 PM
Nice work so far. Can you show the detail behind the Z axis top covers. I'm guessing servo drive via belt to the top of the ATC spindle pulley?

Also, are the gantry ends just covers, or machined from solid (!)

I've looked at that skyfire spindle many times before and been very tempted. Let us know how you get on with it.

Ive also considered the skyfire spindle. I may pull the trigger on one and report back.

Zeeflyboy
26-07-2017, 08:24 PM
looks brilliant!

giladv
28-07-2017, 11:47 AM
hello everyone!

the gantry ends (and all other parts) are machined from solid 7075 T651 but those are covers as well.
i'm including some images without the covers for clarification
223992240122400

Updates
this week iv'e FINALLY got my UDOO x86 single board PC which will be paired with Dynamotion's Kflop motion controller to create what i hope
is the best hobby solution today for machine control. (more updates on this soon)
22404

also, the work has begun on the machined parts(!!)
2240322402

Edward
28-07-2017, 04:26 PM
Hi giladv,
Very interested in your project as I am thinking of building something of similar compact size in the near future and your design looks great.

I also use Kflop with my CNC mill and I love it.

One question, the 1.8 spindle servo, can you tell us what servo you are planning to use? Is is a dedicated spindle servo for higher revs or just the usual 3000 revs?

Edward

giladv
28-07-2017, 10:01 PM
Hi giladv,
Very interested in your project as I am thinking of building something of similar compact size in the near future and your design looks great.

I also use Kflop with my CNC mill and I love it.

One question, the 1.8 spindle servo, can you tell us what servo you are planning to use? Is is a dedicated spindle servo for higher revs or just the usual 3000 revs?

Edward

thanks!
regarding the spindle: the ac servo should be 3500 rpm max (with the driver itself i was able to go only to 3000rpm).
but there is a 1:1.87 gear ratio between he spindle and the motor. so i'm planning on around 6000-6500 rpm at the spindle tip.

best,
Gilad

giladv
05-08-2017, 06:57 AM
hello everyone, just a small update:
2246222463

RobC
06-08-2017, 06:08 PM
Can't wait to see some more shots as you build it!

driftspin
18-01-2018, 10:40 PM
hello everyone, just a small update:
2246222463Giladv,


I am curious about your progress.

Any news?


Grtz Bert

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