Always glad to try and help 
Hi Jim,
Followed your excellent instructions carefully and managed to get my brick to work!!!
However xometry still complains about my object although it now does load. I passed my object thru both netfabb and mesh lab, so I am not sure what is wrong. I am including my file if you wouldnât mind looking it over. It is a pretty simple object.normandnewtab.skp (93.7 KB)
I recall your questions about bending tabs in another thread. Your part has a couple of problems.
The first, and most critical I believe, from a sheet metal fabrication point of view, is that you need to make the bends with a 0.0625" (1/16") inside radius. See this for Xometryâs specifications for this: Sheet Metal Bending: The Basics
Second, your geometry doesnât form a proper solid, in both the SketchUp sense as well as Xometry sense. The way youâve laid your part out would normally make this easy to do, but the bends arenât there ⌠just sharp corners.
Do you have a nominal set of dimensions and angles describing the final part? I can guesstimate from your current geometry, but itâd be a lot more accurate to start with the references (and tolerances).
Iâm not sure how Xometry feels about faceted curves instead of true arcs, but this sample 1/16" thick 1"x1"x1" part with 48 segments in the bend converted and uploaded as a STEP file just fine:
Xometry seems to think itâs okay and quoted a price and delivery:
With some refinements to your model, it should be something that Xometry can make for you.
q.e.d.
never said nor meant this but simply to stay away from the IGES format if you can use STEP or SAT.
yep.
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Jim,
The final product should be made from 20 gauge sheet metal. I just used 1/16â thickness for convenience. How did you make the bend in your example, i.e., which workshop did you use?
Jerry
I created an outline of the âelâ and then used the Push/Pull tool to extrude it. This is simple enough to do, but the bends where the cut metal is angled results in a helical surface along the edge as it wraps around the bend. This is a little more difficult, but it seems like something that shouldnât have to be spelled out.
If you havenât already, you should download their sheet metal guide. Like any manufacturing process, there are limitations and trade-offs. I played around with the sheet metal workbench in FreeCad, but it only does bends that are at right angles to everything else. Kind of a Follow Me / Extrude operation.
I sent this drawing off to Xometry to ask them whatâs the best way to present your request:
Itâs been 25 years since I did any sheet metal design and times have changed (a lot). However, itâs still basically a flat part thatâs cut and bent. Maybe a 2D flat (unfolded) layout will suffice. Iâll let you know what they say about it.
Jim,
I started with FreeCad and noticed the same problem with their sheet metal software. That is why I switched to Sketchup,
although I really like the parametric approach of FreeCad.
Jerry
From Xometry:
Thanks for reaching out. In general, we can work directly off of the CAD model when manufacturing sheet metal parts - we donât need a fully dimensioned print. This is not always the case, but for this part I believe we would be able to work directly off the model.
As for your second point - youâll have to specify what kind of tolerances you will require for the features in question. Our standard sheet metal tolerances are +/- 0.020. You can add specific tolerance requirements on the âFeaturesâ tab after you have uploaded your CAD model.
I didnât quite get a clarification as to whether or not they need the radiused bends, but it doesnât sound like they do. I took your model and reworked it for 0.0375" (20 gauge) and converted it to a FreeCAD shape. Then I exported it as a STEP file (not an IGES file, @sketch3d_de ). Hereâs how it looks in A360:
I uploaded it to Xometry and this is the result (kind of pricey, if you ask me):
I took the âundersideâ faces of your model and extruded them âupwardsâ 0.0375" and then connected the corners and deleted the inside stuff. I shortened one tab and made the other a mirror image.
jh_newtab.skp (29.6 KB)
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Hi Jim,
When you say connected the corners do you mean the bends? If so I had to do that also.
And deleted the inside stuff means you had to make the object hollow (as I did)? Why did you make the tabs smaller?
I agree the price is a bit steep. I will want to do multiple pieces but each is a bit different.
One offs are always more? It seems we have done the hard work designing the piece and cutting the flat projection should then be easy as it will programmed for the machine? I donât know if the bends are done manually?
Jerry
Jerry
It doesnât sound like Xometry needs the bends to be specified ⌠they will bend it so that the flat pieces end up where you want them. I tried several different approaches in using groups and converting to STEP files. Ultimately, I decided that it needs to be a âsolidâ before itâs acceptable to Xometry.
I thought it might give more clearance for bending ⌠it was just for examples sake and trying to find you a workflow that will work. I would start with the flat model and extrude the thickness outwards. Joining the peaks and erasing the inside easily makes it a solid that is acceptable to Xometry. You can also attach notes and drawings to clarify critical dimensions.
Jim,
Because sheet metal is so expensive, I am going to try plastic. I am changing some of the bend angles and will make the plastic slightly thicker. Why am I getting all the extra lines on the planes?
normandnewtab.skp (80.4 KB)
Jim,
I erased the tabs and redrew and re-rotated them and now the superfluous lines are gone. Earlier I sent your sheet metal design to shapeways to see if the plastic would be thick enough and to check the color. It will be here Monday. Thank you for all of your help!!
Jerry
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