Quick lunchtime project

jhitesma · July 24, 2017, 1:44pm

Ok, I cheated a little and did the CAD last night before bed - but the rest was done over lunchtime today.

I have a bit of a thing for fountain pens and recently took advantage of a sale to pick up a bunch of ink samples. So I needed a way to organize them. With my new needle cutter for the MPCNC working so well I figured it was a good excuse to cut some foam and learn how to prepare DXF’s in onshape.

First step was to go a little overboard modeling an ink sample vial for scale…had to use a loft instead of an extrusion since the vials are very slightly tapered. Then drew up the parts quick and dirty. I just went with 5mm thickness which left things a little loose as dollar tree foamboard is actually more like 4.8mm - but I was in a rush and wasn’t going for super fancy:

[attachment file=39238]

That’s looking pretty good. And exporting DXF’s from sketches in onshape turns out to be super simple, just right click - hit export and select DXF. Easy Peasy.

Pulled them into estlcam, generated 6mm deep engraving cuts on all paths at 20mm/s and got my gcode.

Fired up the new needle cutter:

[attachment file=39239]

And 3 minutes later had my parts…my glue gun hadn’t even finished heating up!

But once it did:

[attachment file=39240]

Not bad…but do the vials fit?

[attachment file=39241]

Woo Hoo!

Except…for some reason I thought I only had 12 ink samples. Turns out I actually have 16…and more on the way. So…need to redraw this as a 3 row 18 vial stand! But the quick and dirty way I modeled it causes the sketches to blow up when I try to do that…so easier to just start over which I’ll do tonight.

May also try to get a little fancy and do score cuts leaving flaps along the exposed edges so I can peel off the foam then wrap the paper around for a more finished look. Might as well also adjust the tab sizes to be more accurate, and add tabs to the back/bottom so the whole thing can assemble without glue even if I still plan on gluing it.

If anyone wants them here’s the Onshape link:
https://cad.onshape.com/documents/26c5dbdf387958db5a35973c/w/0dbfcdf4faaea8042fe0bb64/e/a25d56fedcf6ea3f4c1f0704

And here’s my exported DXF’s, estlcam 10 project, and generated gcode:
https://drive.google.com/open?id=0B5JVPXZ3vDfBUC0xOE9iTzlDR00

Overall not a bad way to use the last 15 minutes of my lunch break

jeffeb3 · July 24, 2017, 1:47pm

Slick!

vicious1 · July 24, 2017, 1:48pm

AWesome!

jhitesma · July 25, 2017, 1:49pm

So as threatened I decided to “improve” this. Added a 3rd row to hold all of my ink samples, made the tabs thinner so they match the size of the foam board better, added flaps on the shelves to hide the cut edges, and added tabs so the whole thing actually holds together quite nicely without any glue at all (though I still glued it.)…oh and I added some no-skid feet made from drops of hot glue. Because I could.

Assembly is a little trickier. But not bad. Saving the bottom for last, and add the sides just before that is the trick.

[attachment file=39319]

I was kind of rushed to get this one CAM’d, cut, and assembled in the time I had available over lunch…so my glue work isn’t the prettiest. But you can see how the wrap works to hide the edges. Basically the cut files have a line 8mm from the “pretty” edge which is done as a 2.5mm deep score cut. You then snap the foam on that score and peel it off leaving just the paper. Add a little bit of glue then press the edge against the table to wrap it while squishing the glue out. Leaves a very nice edge and if you’re more careful than I was about how much glue you use even the bottom comes out quite nice.

[attachment file=39320]

There are quite a few tabs on slots on the design this time. Even so after assembling I realized I should have added one more inner support under the bottom shelf to give it a bit more strength. Oh well…maybe I’ll do a v3 just for giggles.

[attachment file=39321]

Still holds ink just fine! I left the vial holes a little tight…I figure I’d rather they be too tight than too loose and they’ll loosen up over time - foam is very forgiving.

[attachment file=39322]

Other than the missing support the only thing I’m not really happy about is I didn’t do anything to hide the cut edges on the sides. Dealing with the curves and both inside and outside being exposed meant that anything I could think of would be a compromise that would still leave something less than super clean. I guess I could have left the mess on the outside then laser cut panels to go over it…hmmm…maybe I should do a v3.

Anyway, DXF’s (individual for each piece as well as an all in one), estlcam project, and gcode files here:
https://drive.google.com/open?id=0B5JVPXZ3vDfBUGZBUE9MTGRKNVU

Original Onshape document here:
https://cad.onshape.com/documents/abc424c412d03b1bc8deec94/w/ff03eb371a488642326a3631/e/555ac78a6769253128418fc6

I did learn a new onshape “trick” with this. Adding all those tabs got tricky - I wound up in a dependency loop where I wanted to go back and modify a previous sketch based on geometry that was created later. But that’s not possible. So instead I ended up doing some additional sketches/extrusions/boolean operations to form the tabs/slots and then went back and created new “template” sketches off of the final parts which I then exported as DXF for my cutting files. Not sure if that was the best way to do it…feels kind of “dirty”…but it worked.

jeffeb3 · July 25, 2017, 2:43pm

I think making dxf from new sketches is reasonable. I did that just the other day. The 3D tools are there for a reason, and getting those parts back in dxf is the only way they are useful.

Looks like your crushing the onshape CAD. Certainly a skill that will be it’s own reward.

jhitesma · July 25, 2017, 3:04pm

Thanks, just feels…convoluted and duplicative to use a sketch to create a 3D part…then create another sketch based on that 3D part.

Originally I was just using my original sketches - but then I got into the dependency circle.

Then I tried the drawing function to create drawings of the parts and export those…but the dxf’s generated by exporting drawings were terrible and full of lots of other stuff I don’t need. Not well suited for cut files.

The two sketches method works…but part of me keeps thinking there must be a better way!

I really am having fun with Onshape, I want to like Fusion…but it just doesn’t run as well on any of my computers. And logging into it is kind of annoying due to how my password manager works. since onshape is in-browser it just gets filled in automatically. Fusion I have to start fusion, then go back to my browser to access my password manger - manually figure out which password is the right one ( due to how autodesk’s system has changed over the years I have like 5 or 6 in there but only 1 still works) copy it, then go back to fusion and paste it in.

But Fusion does do CAM so I really want to spend more time with it…if it wasn’t such a pain to login to for me and ran better on my older computers I would probably use it way more than Onshape.

Either way my big bottleneck is just thinking up excuses to design/make something in the first place Or rather thinking up things that are simple enough I’ll actually complete them

jeffeb3 · July 25, 2017, 4:22pm

If the part is meant to be cut though, you can just “use” the whole thing. I name them something like “top_cut” and I just push them all the way to the bottom so I don’t accidentally depend on them. Maybe next time, you won’t work so hard on the first sketch is there’s an easier way to do it with the 3D stuff.

Fusion doesn’t work in Linux, OnShape does. So I’m not a fan of fusion. I saw this old Tony doing some CAM in it and it finally seemed to make sense, but I haven’t tried it since then.

jhitesma · July 25, 2017, 4:25pm

Yeah, next time I definitely won’t put as much effort into the initial sketches I had to edit the projected sketches based off the 3d parts anyway to add the bit that gets score cut to create the paper flap that folds over the edges. I feel silly spending the time to add those to the original sketches now since they weren’t needed for the 3D parts.

I REALLY wish I could get estlcam working in wine…because the computer in my shop is pretty old and runs terribly on windows but pretty well on linux. But I love estlcam so I’m stuck with windows on there for now. I’ve tried to get it going in wine but haven’t had any luck

What are you using for CAM on Linux? If I could find something as nice as estlcam on linux I’d love to ditch windows on this old machine once and for all…

jeffeb3 · July 25, 2017, 4:31pm

I have EstlCAM working in wine (well, in playonLinux). I think I detailed it in a post here somewhere. In response to another thread about EstlCAM. Everything works but the fonts. Let me know if you can’t find it. There were a few packages I had to enable, but it worked fine. I even have it registered.

dkj4linux · July 25, 2017, 5:04pm

Whoa! You have Estlcam running in Wine??? Yes!!! Details, please. This is the best news of the day! Had no idea someone had figured it out!

Thank you, Jeff!

barry99705 · July 25, 2017, 5:54pm

https://www.v1engineering.com/forum/topic/estlcam-under-linux/

jeffeb3 · July 26, 2017, 1:05pm

Of course, talking up Linux and OnShape, and I’m having performance issues with it today… C’Mon Internet!

barry99705 · July 26, 2017, 1:34pm

They have a pill for that…