5 Channel Thermocouple Gauge/Amp w Analog Out & More

[audifreakjim]

As-is sounds good. If a power cycle shows it as failed and keeps it from alarming, that's good to go.

[loxxrider]

Last week I got the chance to try making some hardware fit in a nice little box. Unfortunately, I didn't account for a few things and it doesn't quite fit everything in the configuration I wanted it to. I will have to find a slightly bigger box. It was a good learning experience though.

I had to use a dremel to cut most of the holes out unfortunately. I will come up with a way to avoid that in production models (templates, jigs, waterjet, etc). I have a die for the thermocouple connectors, but it doesn't quite work for the outer connectors, and it definitely doesn't work for the HDMI, USB, etc.


Here are some pictures. Please ignore how rough everything is (especially that floppy TC port lol). This was just me experimenting with different layouts, trying to make the smallest enclosure possible work.

TC ports

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Analog outputs, power, and HDMI out to LCD display (HDMI connector will probably not stick out like that)

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Chap-stick for scale. The box in the background is another one that I ordered for consideration, but it is too big and expensive.

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Over the past few days, in-between 18 hour shifts and despite the most contradictory and conflicting documentation I've ever received with an electronic component, I somehow managed to wire up the RGB backlit version of this display. I only had to fix a line or two in the code that I'd already written but had been unable to test and it worked. It had a strange "beat-like" flicker to it though, and it turns out that one of the PWM pins I was using runs on a different timer than the other two. Not the most fun kind of issue to chase, but I managed to track it down in a reasonable amount of time. That would have been super annoying to have to deal with! It's perfect now though

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I haven't taken it in the car to find out what settings produce the stock instrument color yet, but I do plan to do that and send them out with that as the default setting.



Up next, find and order another box, test fit hardware in new box, test running the LCD via HDMI, design and procure PCBs for both the LCD and box components, and figure out how to optimize the manufacturing process.

[loxxrider]

Plenty of combinations to choose from

[PRY4SNO]

Nice developments, loving the updates Chris.

Sent from my SM-G900W8 using Tapatalk

[loxxrider]

I've decided to take matters into my own hands with the enclosures, and have purchased a high end (for it's size) 3D printer to make it happen.

Should be fun

[PRY4SNO]

Yessss

Exciting stuff... both for this project and the others that are surely to follow.

Sent from my SM-G900W8 using Tapatalk

[alxdgr8]

Nice! Finally got around to messing with my 3d printer again for the first time in like 2yrs. Almost want to buy another since there's so many better and cheaper options now.

Sent from my Nexus 6P using Tapatalk

[loxxrider]

I agree I'm excited!

Yeah, there is a sea of options available now and they seem to get upgraded every year, but the really good opinions are limited. One of the best new features in my opinion is auto leveling beds. Take a look at the lulzbot machines. Don't let the name fool you, they're about the most reliable 3D printers available. The price is well worth it from what I read.

[loxxrider]

What fun it is to design for 3D printing. There are so many fewer design constraints (although some are introduced of course) and there is no added cost for the features. I love it!

I hope you guys don't mind trading a prototype-like finish as a trade-off for a better design. Of course I'll try to make the finish as nice as possible though.

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I like this configuration better too. Here's my logic... I see people installing this enclosure with the TC connectors facing "out" of the car, I.E. facing toward the firewall. I'm envisioning it being installed in or near a glovebox or something. I think it's kind of stupid to have wires coming out from the front and back of the enclosure in this case. It should be much better to have them coming out of the back (toward the firewall) and an adjacent side for routing behind the dash or wherever. There is a micro USB port on the front of the box, but that makes sense for when you want/need to plug into it for software updates or anything else you might want to do with it.

[PRY4SNO]

Yesssss

Sent from my SM-G900W8 using Tapatalk

[loxxrider]

The layout is coming along pretty nicely.


HDMI for LCD and buttons, power, and analog output are all on one side of the enclosure.

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Micro-USB port on the opposite side (not the front like I said it would be before, due to space constraints) for programming, updates, etc.

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General layout is now mostly finalized. Brass inserts will be used for PCB mounting and for clamshell closure.

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A sort-of tongue and groove closure at the clamshell will help keep things aligned. The gaps have to be sized very specifically for the printer to be able to print them.

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One more of the general layout with almost all components modeled and in place

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I should get to try out the printer this weekend. Then I'm sure I'll have to change the design a bit here and there based on how it prints. I'll purchase all of the hardware after that. Then hopefully I can assemble a compete enclosure. Then it's on to testing the LCD over HDMI and figuring out how to package the LCD screen, buttons, and connector.

[PRY4SNO]

Two questions.

Will heat be a concern here at all, with the tight packaging?

Also, it's tough to tell by the rendering (which look top notch, btw), but with the micro usb is it mounted flush with the face or inset into the box? It would be nice if the plug went into the case a few mm's to prevent it from wiggling out.

[loxxrider]

Two questions.

Will heat be a concern here at all, with the tight packaging?

Also, it's tough to tell by the rendering (which look top notch, btw), but with the micro usb is it mounted flush with the face or inset into the box? It would be nice if the plug went into the case a few mm's to prevent it from wiggling out.

Good questions.

No, heat does not pose a problem here. The amps and outputs operate at very low voltages and amperages. In fact, I wanted to make it a lot smaller, but the size of certain components has dictated it be the current dimensions.

I was expecting you to say you wanted the micro USB to be flush when I first read that, but luckily for you, it is inset about 4 mm. I didn't like that at first, but you make a good point and I didn't have much of a choice anyway! I will have to make it a big oversized since there are many shapes and sizes of micro USB plugs (the part of it which isn't standardized).

[loxxrider]

Yesss

This is working out nicely. The very first print was 99% successful. The box snapped together satisfyingly with no prost processing at all.

One small detail did not print on one half, but I suspect it will when I make it print a little more slowly/finer like I did on the other half.

Printing-wise the only thing I would want to improve is the finish on the top of the box. I'm not sure it is possible to improve, but I will try different materials and techniques in an attempt to improve that.

There was one component which I didnt have the dimensions of when I made the design, so I will have to make a small change or two to the design to accommodate that, but otherwise nothing needs to be changed.

I think the size is pretty reasonable.

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The print quality is quite good in my opinion. The clamshell gap should close down on the finalized version, especially when it's fastened together with hardware and not just snapped together.

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[ringbearer]

Very fine Chris!

[alxdgr8]

If you're using ABS you can smooth it with acetone. Couple different methods
http://www.3ders.org/articles/20150509- ... parts.html
http://www.instructables.com/id/Quality ... h-Acetone/

Couple other methods:
http://blog.fictiv.com/posts/ultimate-g ... nted-parts

[loxxrider]

Thanks!

I know about the abs trick. I'd prefer not to use ABS, but if that's what it will take to get it right, then I definitely will. I think all of the features except for the flat surfaces are perfectly presentable as-is. A step like adding acetone is a lot harder for me to accomplish while also working in the field at my regular job and would certainly increase cost. Hopefully I can find a solution to make it presentable as-printed!

[FFF]

Fantastic work -

[loxxrider]

So I've been tweaking the design in very small areas and trying to optimize the prints. It's very easy to print on this printer, but getting the surface finish absolutely perfect is not easy. I've had some success getting perfectly smooth bottom and top surfaces, but not repeatably. I'm not sure what made them so good the one time the machine got it right for the two materials I'm interested in.

So far I've narrowed it down to two materials. High impact polystyrene (HIPS) and a co-polyester named nGen based on Eastman's Amphora 3300. The nGen has really nice properties, but is about 3x the cost of HIPS. The HIPS is awesome other than the fact that I've had trouble optimizing the flat surface finish and that it has been warping the parts such that there is a gap where the clamshell design meets. The warping is fairly minimal and the end result is pretty decent. If I could have the surface finish or that fixed, I'd be pretty happy. The surface finish has a chance to work out.

The nGen definitely does not warp as much, so the box fits together more nicely when printed with it. It has similar problems with the flat surface finish though. I'm printing a buttload of test squares to try and get to the bottom of it. For now, the only color of the nGen I have is blue.

The other materials have proven either too difficult to print (so far) or the properties just aren't sufficient. PLA for example is really nice to print with, but it will start to lose it's shape if left in a car on a hot summer day most likely. We can't have that!

Luckily I *just* got a pretty decent one with the nGen. I'm going to keep at 'er to make sure we can get some acceptable results.

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Top right is similar to what I had before with the hips surface finish. Bottom right is the best I ever got with hips. Not sure how.

Bottom left is the best I got with the nGen. Top left is the latest print. Hopefully I can at least repeat that.

[loxxrider]

Tested the lcd screen via hdmi tonight. It was a success!

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[loxxrider]

After extensive material testing, I have what I deem an acceptable solution.

Some pictures of the testing. I probably have 30-40 test parts like that for finish and durability assessment.

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Durability testing. The finish was pretty close to something I'd like here, but you could still see the lines in the finish (through the first layer actually). When I got it totally perfect looking, that's when I had the next problem explained below.

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I figured out how to get repeatable surface finish results with both materials (HIPS and the co-polyester). However when printing like that, especially with the co-polyester, it became extremely difficult to remove the part from the build plate. I tried removal at all different temperatures and even tried freezing the plate to get it off, but I ended up essentially having to chip it off in small pieces and then finally having to melt off the last little bit. It took me hours to get it all off.

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The reason it stuck so well is due to the relatively large, flat surface area of the part, extremely consistent deposition and fusion of the material (smooth finish), material properties, and the build plate coating. So now I am using a different material to print on which gives the part a nice, uniform surface finish and allows for manageable removal of the part. It does however leave a textured finish on the part. I may try some other things along the way if a different surface finish is desired, but I like it actually and I hope you will too. If not, well... that's too bad for now I guess! I was looking for something which would be presentable in a professional product while keeping the process foolproof with no post-processing needed.

Here is the textured, but consistent surface finish I plan to use.

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I have determined that using HIPS is out of the question for now because of the warping. I think a lot of it could be solved with an enclosed work space, but I am not equipped for that at this time. Plus, the co-polyester doesn't give anything up to it in terms of material properties. The co-polyester is heavier, but that contributes to a more quality feel anyway. The only drawback to it is price, but that isn't a huge factor in the grand pricing scheme.

The co-polyester I have is blue since I couldn't get black when I ordered it, but now that I know it is the material of choice, I will be ordering it in black for production (I will make it blue if you want though!).

Up next, figure out what to do with the wiring inside the box (trying to avoid a PCB) and how to do the same for the LCD to keep costs down.

[loxxrider]

Here is a good demonstration of the warping issue with the HIPS material. This particular case of warping is due to the material lifting off of the less-sticky print surface I was using for the co-polyester, but it is present in other places in the part too. The co-polyester does warp a little bit too, but not as much and it allows for a nicer looking closure when the two parts are mated together.

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[themagellan]

oh man - it looks so good.


Simple question (Like always) have you tried reducing the print speed? I'm having a hard time believing it's warping that way. That looks like it has not had the proper time to cool before a new layer (just a thought!)

I have no use for one... but I want one! haha

[loxxrider]

The reason that one warped so much is becuase it lifted off of the print bed. The method I used for that part was better suited for the copolyester. I think controlling the print environment will help warping more than the layer speed will becuase I already have a minimum 20 sec layer time set for that material. I may experiment with it though. I think I want to insulate the machine first.

If I make the minimum layer time much longer, it'll probably hinder layer adhesion unfortunately. I think having the part cool down uniformly will be key. That said, the copolyester parts aren't even close to as bad about this, so I'm not extremely concerned at the moment.

[loxxrider]

Maybe I should make a separate 3D printing thread for sharing the knowledge I've gained in this venture...

Let me first say that this printer is fantastic. When used as intended, it works all the time, every time. However, I have some special requirements and, now, I'm trying to use it out of spec. I bought some AudiSport gray co-polyester filament, but to my dismay when I opened the package, I ordered the wrong size. Stupidly, I opened the package which means I can't return it now, so I figured I better try to make it work. I spent basically all day yesterday trying to get good prints with the stuff, but the filament kept jamming. You see, the extruder is built to use 3.0 mm or 2.85 mm filament, but what I got was 1.75 mm. The problem with that is the thinner filament cannot withstand as much compressive force as the larger diameter filament can before buckling. As soon as the filament buckles, the extruder will stop extruding properly, and eventually it will stop extruding altogether, and the print will be compromised.

To alleviate this buckling, I had to correct two problems. The first problem was the first layer height. To get a smooth finish on the first layer, I was really making the printer squeeze and press that filament onto the build plate. That creates more back pressure inside the extruder for the filament to have to overcome with compressive force. So I eased up on that a bit which helped. That problem may have also been exacerbated due to my new build plate treatment technique. It has produced really great results with a more pleasing finish than the painters tape I was using before (it looks a lot less 1980's-molded-plastic-like). It is a bit thicker than what I was using before though I think. I'll post pictures of that as soon as I get a nice one.

After that, I was able to get past the first layer at least, but I was still having trouble after the second or third layer. The filament was jamming in the extruder. I thought maybe I could try a larger layer height to, once again, alleviate some of that back pressure in the nozzle. That didn't seem to help much which makes sense because it's squeezing out more filament per unit time to make the larger layers. So then I got the idea to raise the extrusion temperature a bit. After I did that, the rest of the part printed beautifully. Now I just need to find the perfect first layer settings for a proper surface finish, and I should be able to make good use of this filament if anyone wants an AudiSport gray box.

I also ordered some hardware and came up with a new captive nut feature for holding the new power jack into the box. I couldn't use a bolt-through design because of the thicker walls of the box I've specified now. I have been really putting these boxes through the ringer. I have been trying to break them as many ways as possible. On one, the floor broke out fairly easily so I added some fillets where the walls meet the floor. I also thickened the walls and am now printing everything solid (no hollow space inside the part) and it has increased the strength significantly in all directions. There is a greater feel of quality as well. Finally, I added some reliefs for things here and there to make assembly easier (and to make it possible in some cases). I'm amazed every day by what you can do with this technology!