Beginer Machining Questions with Shapeoko3

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Athaidesign
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Beginer Machining Questions with Shapeoko3

Post by Athaidesign » Mon Sep 07, 2015 9:01 pm

Hello everyone!

I'm an experienced CAD designer with solidworks software, but completely new to the machining side. I wasn't sure where to post this so board members feel free to move this wherever it needs to be.

I just purchased a Shapeoko 3 to mill out some prototype pieces I'm designing and have some questions about the milling/cutting software.

This is what I will be milling out of .063'' 6061 Aluminum. The dimensions in the drawing are in MM no inches.
Image

From what I've gathered so far I will need to do several different tool paths.
1. drill out the 4 holes
2. countersink drill the taper (Is there a formula or guide sheet to figure out what size drill based on the bolt/screw?)
3. perimeter cut (Flat bit? what size?)
4. chamfer cut (where do I buy this? what size?)

My research tell me I need to run each tool path, re home x, y, axis then re home Z and continue, is this correct?

From what I've gathered what I need to do is use HSM cam inside solidworks then transfer that data over to makercam? Is this correct? Where can I buy those bits mentioned above and what sizes?

I've heard that carbide bits are the best, any recommendation to websites to get them?

Any word of advice would be greatly appreciated. I'm just getting everything as prepared as possible so everything moves slowly when my machine arrives. I'm about to launch a kickstarter and need to prepare everything as well as possible. Please let me know if my thinking process is correct or flawed.

Thanks guys!

WillAdams
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Re: Beginer Machining Questions with Shapeoko3

Post by WillAdams » Mon Sep 07, 2015 9:22 pm

You’re trying for a level of machining on the Shapeoko which no one else has tried and documented publicly AFAIK.

Yes, you would want to drill the 4 holes first. I believe it would be best to do this on a fixture which has matching inserts at the correct locations so that you could then fasten the piece down w/ screws. This is discussed on the wiki somewhat here:
http://www.shapeoko.com/wiki/index.php/ ... abrication

For woodworking, there are special countersink bits, I imagine that this is also the case for metalworking. A quick search indicates so: http://www.endmill.com/countersinks/countersinks.html

Not sure about using them in the machine though — check the RPM which they can be run at.

You can cut the perimeter w/ pretty much any bit, I’d suggest a 1/8" — endmill selection is discussed on the wiki here: http://www.shapeoko.com/wiki/index.php/Endmills

To cut the chamfer you’d need a specialty bit for this as well. A quick search finds: http://www.mscdirect.com/browse/Holemak ... d=12106119 again, you’ll need to check the appropriate RPM which these can be used at.

You would use the HSM machining CAM process w/in Solidworks to make a G-Code file which you could then send to the machine using Carbide Motion Machine Control Software, or your choice of Communication / control program. software overview here: http://www.shapeoko.com/wiki/index.php/Software

HTH!
Shapeoko 3XL #0006 w/ Carbide Compact Router w/0.125″ and ¼″ Carbide 3D precision collets
Nomad 883 Pro #596 (bamboo)

heathenx
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Re: Beginer Machining Questions with Shapeoko3

Post by heathenx » Mon Sep 07, 2015 10:18 pm

Chamfers can be difficult with an unlevel wasteboard. You can use a chamfering bit, center drill or bull nose end mill. I dont normally chamfer any more than .020" max. Seems to be plenty for breaking an edge.
Shapeoko 3, #405 / Dewalt 611 w/Super PIDv2, limit switches

WillAdams
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Re: Beginer Machining Questions with Shapeoko3

Post by WillAdams » Mon Sep 07, 2015 10:42 pm

Yeah, I’d envision the fixture as having been machined to have a pocket to hold the stock, one which would be flat and level relative to the machine’s workings.
Shapeoko 3XL #0006 w/ Carbide Compact Router w/0.125″ and ¼″ Carbide 3D precision collets
Nomad 883 Pro #596 (bamboo)

krtwood
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Re: Beginer Machining Questions with Shapeoko3

Post by krtwood » Tue Sep 08, 2015 1:41 am

It's possible to create a countersink with a straight bit by making concentric circles with depth matching the angle of the countersink. There's a plugin for vectric vcarve/aspire for doing such a thing but those are of course fairly expensive programs. The resulting countersink is of course always going to be slightly stepped with any reasonable number of passes but of course it gets covered by a screw so the surface doesn't have to be perfect.

Athaidesign
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Re: Beginer Machining Questions with Shapeoko3

Post by Athaidesign » Tue Sep 08, 2015 2:29 am

WillAdams wrote:You’re trying for a level of machining on the Shapeoko which no one else has tried and documented publicly AFAIK.

Yes, you would want to drill the 4 holes first. I believe it would be best to do this on a fixture which has matching inserts at the correct locations so that you could then fasten the piece down w/ screws. This is discussed on the wiki somewhat here:
http://www.shapeoko.com/wiki/index.php/Designing_for_Fa
krtwood wrote:It's possible to create a countersink with a straight bit by making concentric circles with depth matching the angle of the countersink. There's a plugin for vectric vcarve/aspire for doing such a thing but those are of course fairly expensive programs. The resulting countersink is of course always going to be slightly stepped with any reasonable number of passes but of course it gets covered by a screw so the surface doesn't have to be perfect.
WillAdams wrote:Yeah, I’d envision the fixture as having been machined to have a pocket to hold the stock, one which would be flat and level relative to the machine’s workings.
heathenx wrote:Chamfers can be difficult with an unlevel wasteboard. You can use a chamfering bit, center drill or bull nose end mill. I dont normally chamfer any more than .020" max. Seems to be plenty for breaking an edge.
brication

For woodworking, there are special countersink bits, I imagine that this is also the case for metalworking. A quick search indicates so: http://www.endmill.com/countersinks/countersinks.html

Not sure about using them in the machine though — check the RPM which they can be run at.

You can cut the perimeter w/ pretty much any bit, I’d suggest a 1/8" — endmill selection is discussed on the wiki here: http://www.shapeoko.com/wiki/index.php/Endmills

To cut the chamfer you’d need a specialty bit for this as well. A quick search finds: http://www.mscdirect.com/browse/Holemak ... d=12106119 again, you’ll need to check the appropriate RPM which these can be used at.

You would use the HSM machining CAM process w/in Solidworks to make a G-Code file which you could then send to the machine using Carbide Motion Machine Control Software, or your choice of Communication / control program. software overview here: http://www.shapeoko.com/wiki/index.php/Software

HTH!
Thanks for all the reply guys very useful stuff. I did not know all this hasn't been documented on the boards yet. I guess I'll be the first to volunteer after I master the process on my own accord.

Say hypothetically for another project that needed chamfers where the wasteboard is not leveled. Would it be best to start with a thicker material and shave down the top a bit to make it level?

Gadgetman!
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Re: Beginer Machining Questions with Shapeoko3

Post by Gadgetman! » Tue Sep 08, 2015 6:35 am

You always want to avoid shaving the material. It's a long, slow process that usually leaves a less than perfect result.

As for the original question, it's not too difficult to cut your design, just timeconsuming.
Because of the chamfers and countersinking, I would probably have done it with a ball-head endmill.
A 1/8" would be perfect, depending on the size of the holes, of course.

The biggest problem is making certain the workpiece is perfectly level before you start.
Weird guy...
Shapeoko 2014F: 1000mm X/Y, 300W Quiet Cut spindle, Arduino Uno/G-shield and GRBL 0.9i
15x30 drag chains, custom spindle mount, 9mm belts, 8mm endplates, 6mm motor plates.

heathenx
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Re: Beginer Machining Questions with Shapeoko3

Post by heathenx » Tue Sep 08, 2015 11:02 am

You can do what I do when I'm a little unsure of things...cut the whole thing out on some scrap wood before attempting the aluminum.
Shapeoko 3, #405 / Dewalt 611 w/Super PIDv2, limit switches

Gadgetman!
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Re: Beginer Machining Questions with Shapeoko3

Post by Gadgetman! » Tue Sep 08, 2015 12:00 pm

I would rather use some decent wax than wood for testing this design, though.
(Wax is much more forgiving of the feeds/speeds than wood, so that he can run the G-code with the correct settings without risking the durn thing catching fire...)
Weird guy...
Shapeoko 2014F: 1000mm X/Y, 300W Quiet Cut spindle, Arduino Uno/G-shield and GRBL 0.9i
15x30 drag chains, custom spindle mount, 9mm belts, 8mm endplates, 6mm motor plates.

heathenx
Posts: 114
Joined: Thu Apr 02, 2015 10:59 am

Re: Beginer Machining Questions with Shapeoko3

Post by heathenx » Tue Sep 08, 2015 12:45 pm

Gadgetman! wrote:I would rather use some decent wax than wood for testing this design, though.
(Wax is much more forgiving of the feeds/speeds than wood, so that he can run the G-code with the correct settings without risking the durn thing catching fire...)
Note taken, except, wood is much easier to come by at your local hardware. I'd even suggest balsa or bass wood. You won't break any bits with that stuff. I am interested in wax, though. Where do you source that?
Shapeoko 3, #405 / Dewalt 611 w/Super PIDv2, limit switches

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