Hello again So I have this part I want to machine, but it's my first time on my Openbuilds mini mill. The part is about 10x20x20mm and in aluminium. When I save out the part as an dxf it comes in my Openbuilds cam as one circle and four line segments and two arc's. The cam does not seem to be able to handle the six segments as a perimeter before they are joined. I've tried a number of different versions of autocad formats, from ver 14-2018, both binar y and ascii without luck. How does one go around this problem? Please anyone!
Convert all the different types of entities in the DXF to Polylines: see docs:software:file-errors [OpenBuilds Documentation]
Thank you very much Yes I understand that, but there seem to be no option for that in Solidworks, so I would have to use a 3d-party program then, any free or online version for that? I also forget to ask, why are the part located outside to the left of the grid in Open Cam, and how do I define the size of the stock in Open Cam?
Your DXF has the part drawn in the negative offset - there is an origin in your sketch as well. If you set it bottom left, your drawing will be bottom left. You don't. Your drawing is already a fixed size (hopefully when you drew it you kept stock size in mind)
Thanks again Fixed all except the stock size, my stock is a bit bigger than the part, so how many millimeter/passes does it cut/do outside the perimeter when the bit used are 6 mm?
Hello again. I've installed HSMXpress as a plugin in my Solidworks CAD and I see that they have a post processor for GRBL(Version: 43553, Post Library for Autodesk Fusion 360 | Autodesk Fusion 360), so I want to take this into Openbuilds CAM. What speed and feed would I try as a start for this small part in aluminium, the part is 20x20x10 mm. I was thinking of doing three face millings operations to get the part to size, then do a contour for the two fillets and a drill true for the 4 mm hole. I have the choice of 3 mm(one, two and three flutes), 6 mm(one and two flutes) and 8 mm(three flutes) end mills in AMB (Kress) 1050 FME-P - ER16. I've been reading that as a starting point I could use 1/2 diameter(Ø) of the endmill for width and depth of cuts and 10000 rpm(my motor 5000-25000 rpm, Effective power: 600W), but I can't find much about the feed. Also what speed and feed would I use for the 4mm drill through operation, would I peck or just drill through the 10 mm dept? Are there any links to maybe a spreadsheet for speed and feeds for the minimill. I also guess I could do this with the surfacing wizard or just manual with the joging, but then again I need the speed, feed and rpm. Terje
If they have a Post, then you use HSM express to generate the gcode. Not openBuilds CAM anymore. If you have a Paid advanced CAM, why would you use a basic entry level Free CAM You'd use OpenBuilds CAM if you didn't want to pay for a proper CAM like HSM, etc See the CAD/CAM/CONTROL stackup again: docs:software:overview [OpenBuilds Documentation] for an overview Speeds and feeds take a little research and learning curve to get right, but start on the very conservative end of the scale as a starting point - remember extrusion based machines can deflect - so the SFM calculators that assume a massive $100,000 cast steel mill's values, would not translate well to a smaller desktop machine.
Sorry, I meant Open-builds control. Yes that´s exactly my concern, I think the speeds and feeds HSMXpress is coming up with is for commercial machines, so where should I start with this hobby CNC. This is my first part ever with CNC, I`ve only used the CAD part of SW before.
Also, if you search the forum (magnifying glass icon top of the page) for "feeds and speeds" you will find quite a few resources. Alex.
I just remembered, youtube search winston moy and nyccnc. Winston has cut a lot of aluminum parts using a machine similar to openbuilds machines. Nyccnc has a ton of speeds and feeds calculation info, but search his videos for shapeoko. There's at least one video on cutting aluminum there.
Terje Moe, I'm curious, did you ever get HSM express to work properly with your OpenBuilds machine? Thanks!
