Community challenge #11: multi-sided machining (closed)

I feel we all are going to be shown our places when this post drops.

Second place is the new first place!

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If there’s one thing I’ve learned after joining this forum is that you can’t underestimate anyone. The amount of creativity and sheer diversity of ideas in this group is really astonishing and we definitely have a few wild cards around!

Plus a contest like this is the perfect opportunity to try something new, dare to step out of your comfort level and grow.

I won’t be posting anything old. I’m trying something fresh and a little scary. Something that has a large opportunity for failure but will help learn and adapt work holding and machining strategies. Also if anyone feels my entry could potentially stifle their creativity or drive to make something, I’ll happily disqualify myself.

Working on the CAM tonight, it’s a doozy :grin:. Best of luck to everyone and its awesome to see the entries already coming in!

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That moment when you realize you better order a new end mill fast to take it to the next level…

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Im calling this one “twisted bowl”

Twisted bowl file

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To get an entry in, a piece I call “magnetic door catch for Snap On KR274”

The cabinet is a side hanger of a certain age that never had any door latch provision except the cam lock. This is REALLY annoying, since it meant that to keep the door from opening, the key must be used. It rattles if bumped. The lock cam turns on it’s own if the key is left in, which makes opening and closing more annoying, and also scrapes up the paint.

So, a magnet.

The model:


A rare earth magnet in the hole is attracted to the center shelf of the box when this in mounted in the flange of the door:


to hold the door closed

No fasteners used. It pops into the hole in the flange and is held with no play by the door skin.

How this was machined:

A pocket was cut in the wasteboard to hold a chunk of Nylon rod:



The pocket stock-to-leave was adjusted for the bore operation (the last op) several times and the operation repeated to get the correct fit.

The origin is in the pocket, centered in x-y, but level with the bottom of larger bore. This will be shown later. Setting zero to bore the pocket required finding the wasteboard surface and setting the z there to be 5mm t get a 5mm deep pocket. This made it unnecessary to reset the zero at all.

The stock:


fixtured

for these operations:

The setup for the first end allows for the stock oversize on the other end, so there is bottom extra stock as well as top.


The nubbin and edges are chamfered using a ball end, since it is a small chamfer. Just enough to break the edge to install the part when done and make inserting in the fixture hole for the other end easier

The machining:



Then came the other end. The same fixture was used. so the origin is actually within the part.

This allowed the origin for the first end to be at the surface of the raw stock, which makes things a lot easier. It was easy to place it for this setup, since it is a point on the plane cut on the first setup, a plane in the model

There is less surface to grip and more flex since it isn’t the full round. For a one off, I just reduced the tool engagement a lot to avoid pulling the part out. May not have been needed, but whats an extra 15 minutes?

followed by boring the hole for the magnet. The bore was done with an adaptive operation, and I adjusted the parameters for periodic retraction (by limiting the pass depth) to help clear chips.


Note the skin left over. I expected this as a possibility, but didn’t worry about it. Came off real easy. Minor dimensional adjustment would take care of it on a repeated job.

Installed the magnet using a wood dowel as a punch (I have no brass punch small enough)

and installed in the cabinet. The hardest part was putting the hole in the door flange. It is 18Ga (nearly 1.5mm) steel.

I didn’t bother to fancy the model up. Just a quick job to meed a need. No artistic merit here. Just

mag-catch.zip (1.9 MB)

should anyone want it.

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First post on the forum! I have been lurking around here for a few months learning many things from other users so I thought I would try to contribute and share a small part machined on the Nomad this weekend. The cover for the lamp on the stove was broken when I moved in to my apartment so I thought I would machine a part that would shield the lamp and diffuse the light. To try and achieve this I modelled a part in fusion 360 with a “pyramid pattern” on the inside of the cover using two perpendicular V-grooves and rectangular patterns. (Perhaps this could be readily machined using a V-bit instead of the hours I spent machining it with ball end mills).

I machined the part in polycarbonate and flipped the part once using 4 mm dowel pins to locate the part using the bed as Z0.

The part is pushing the smaller build envelop on the Nomad a bit so I did a dry run with the end mill 5 mm over the bed to see that I did not hit any end stops with the first toolpath. I used 2mm and 3mm flat end mills to try different speeds and feeds to clear out the majority of the material and a 2.5mm and 1mm ball end mill in succession to machine the light diffusion pattern. There were some small strands of polycarbonate still attached to the pyramid pattern after finishing with the 1 mm ball end mill, perhaps I should have done a spring pass with the same end mill to clear that out but I was too eager to see the part finished.

!

I cut out the part using tabs but should probably have used double side tape or the machined screw holes for holding the part down as the tabs left small blemished on the part that light up a bit when light is passing through the cover.

I was mindful to not machine the bottom surface of the part as I wanted it as transparent as possible. The idea was that the light diffusion pattern would diffuse the light but I think the majority of the light diffusion is done by scattering caused by the ridges left by the finishing toolpath (1mm ball end mill with 0.1 mm stepover).

Before and after picture!

Link to CutRocket (Pretty specific for my stove lamp haha… But perhaps it could be useful for someone to look at the speeds and feeds or the modelling of the “pyramid pattern”: https://cutrocket.com/p/5f14c01312573/

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Brilliant. I am going borrow that idea for my stove hood!

And welcome aboard another Nomad owner!

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Team Nomad is on fire !
It’s interesting to see such diverse entries, yet another testimony to the versatility of our machines.
(and welcome @Olle! no better way to make a first post)

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Thanks for the welcoming guys! I’d love to see that part if you end up machining something similar @PhilG!

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Why not throw another one in, since at the moment I don’t think I’ll have the time to do something artsy. Another part for a comparator. This time a riser with a fine vee-groove for inspecting and measuring small round things (tools for the Nomad, among other things, but actually made so I can inspect pars I am working on for actual work)

This is based on the same base model I posted the other week. All I changed in the model was the height (parameter value) and the groove profile.

The model:

This was machined in two setups. The first was from raw stock. Here, the stock was pocketed into the wasteboard,

using the same socket as the last time (put in by the scheme bore, measure, rebore and test fit, repeat until proper snug fit). Again, I didn’t bother cleaning up the stock much. The ends were square enough to finish-- flat within 1.5mm stock allowance either end.

Machined the bottom side, bored holes for 3mm dowels,

and surfaced new location for the second side mounting and bored fresh dowel holes to insure perfect zero (drill at 0.9mm, then bore using 2.4mm flat mill)


then pop in the part for setup 2 with double-sided tape to keep it down:

For both, the zero is center and at the mating surface with the wasteboard. The first setup had stock allowance on the bottom, as it was rough, so the zero was on a stock point. The second, being a finished surface, the zero was on the model. The machining on the first setup did the perimiter a bit over half way down. The second setup did the same.

Then the vee groove using a 45 degree chamfer bit

perimeter with a ball end, and a narrower vee bit (60 degree vee carving) to clearance groove the center of the vee slightly. The bit has a slight flare at the tip to make the 0.1mm flat, and in this case, it the ideal tool for a narrow clearance groove, much better than the smallest ball end I have on hand.

The product:


The top is dead flat though there is shadowing of the tool path. There is flat patterning due to the interpolation, but the size of the flats relative to the size of the part (100mm-ish) looks large, but the max error is less than 0.02mm on the round surfaces.

Setup on the machine with a tool for inspection (a 135deg split point drill. Done several hundred holes in T-11 chrome-moly material, looking at condition. Tough to photograph, as the HDPE is SO bright when the illumination is on):

IMG_0081
IMG_0082
IMG_0083
IMG_0084

The models and setup sheets (inventor) for those interested:

riser2-with-cam.zip (2.3 MB)
riser2-with-cam-setups.zip (2.1 MB)

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This is my favorite project I worked on with my kid. We made iPhone cases on our Nomad 883, and our own two sided jig to help us get repeatable results.

So let’s start by looking at 8x8 Nomad 883 waste board we modified. The left side of the waste board was pocketed to perfectly hold 3" by 5.5" blocks of wood (two sided tape in the middle for insurance).

We could then CNC one side of the iPhone case.

Once one side had been cut, we could flip it over onto the right side of our waste board. The slots on the right side of the waste board held the iPhone case in place so we could CNC artwork onto the back side of the case.

We then got into different inlay materials, and could customize cases with unique designs. The “Cold Coffee” case was my kid’s, we inlaid a circuit board that was pulled from a dead inkjet printer. And then added a copper inlay as it was somewhat like the color of coffee.

I think that case got even better looking as it aged. This is what a teenager does pulling a phone out their pocket a million times a day.

The very first photo of the “Visual PLB” case (that I took today) is my current iPhone case. I have used this case for over 2 years. I’ll admit I cleaned it up for this photo, but the brass and bamboo have held up WAY beyond my expectations. Bamboo is by far my favorite material to CNC.

iPhone5.mcf (20.0 KB)

iPhone5 PLB.zip (1.6 MB)

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Oh boy, now I have to try “PCB inlays”, that looks fantastic
The “side by side flip jig” is very nice too :+1:

Some love for the Shapeoko :smiley:

Watch a video of my 3 setup/ 4 bit change toolpaths here:

F360 design here:
https://a360.co/31al5O2

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Nice ! Now you have to tell us what this is for? watercooling system ?

Looks like a hotend for a 3D printer.

It’s an all in one x-carriage, hot end and direct drive extruder mount for CR10s and Enders. This will replace a bevy of heavy sheet metal and an underperforming stock hot end.

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@Liquidice Awesome work! Love the cooling fins and standoffs for the fan! Any heat transfer calculations on the fins? (I mean, it looks plenty capable I’m just curious).

I might have to do something fun like this for my Wanhao i3…looks like you have the Z-Plus for your Z-axis? Looks more than capable in aluminum!

Nice work again!
Kyle

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I ran a FEA analysis in fusion 360 with a nozzle temp of 220C; outcome put fins in ~35C range with cold end of the heatbreak zone at around 45C.

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Working for Autodesk i get so many people on CNC threads complaining about Fusion 360 and that Autodesk is trying to just take your money. But when i see someone like you take advantage of high end FEA capability to solve a problem, I get happy. There is so much value in Fusion360 beyond Modeling and CAM for such a small price. Nice work.

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10/10. Fusion360 is an incredibly powerful tool, and when it’s time for me to move from a free plan, I will purchase a license with zero complaints.

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