Substitute for ABS for electronic enclosures (heat)

I’ve been using (attempting) to use abs to build some parts that will be housed in an electronic enclosure of sorts, which can get pretty hot. Maybe around 90-100C at max. It’s for a 6 bay battery charger for my uav and I haven’t actually measured the heat - it’s just a rough guess (there is a fan to exchange air so it might not get that hot). This has been a long project. I have 2 pieces that are 300+ grams/15 hour prints and individually take up the entire bed of the Taz 6. They are 2 halves to a single part.

I’ve been trying to use ABS for these, but they warp pretty badly no matter what I do. The first 15 or so layers are pretty good, but then the corners start curling up after a few hours. I’m using a 10 line brim and can’t increase it any more as there isn’t space. These 2 parts connect together to make a surface that fits in a Pelican 1550 case. They need to be flat with no/VERY minimal warping. Ive had the heat bed set to 110-115C and tried various nozzle temps. I think my first layer is pretty bang on. Spent several hours calibrating the extruder, z-height, x/y/z axis and on a 40mm cube I’m at like 40.02 - 40.04mm within all axis.

The only reason I am trying to use ABS is its high heat tolerance. I really don’t want to build an enclosure to print these. So, does anybody have a recommendation on a different filament that has minimal warping and is pretty high temp resistant? I’ve read that PLA can warp just sitting in a hot car. They need to be strong and take heated inserts.

The abs works really well for smaller parts, just not these large ones that take up the whole build plate. Yesterday it was really hot here (around 100). I would have thought that extra heat might help a bit but it didn’t. I’ve gone through 2kg of abs and can’t perfect it. So, I’m looking for a good solid alternative and would appreciate any suggestions. I don’t have a very wide exposure to different filament types.

Edit: just to add I’m using Village Plastics ABS from the lulzbot store.

Proto-Pasta High Temp PLA can withstand up to 140°C (285°F) after its been annealed.

Comes in Silver and Ice. And Coffee but the Coffee is more difficult to work with.

I print it at 215°C on an unheated Zebra Plate (PrintnZ) bed. I anneal at 180°F for 30 - 60 minutes. There can be a small amount of shrinkage that you may need to account for.

Kenny

That sounds interesting, although I was hoping to stick with black, which I didn’t mention. Translucent would be ok too as there are 6 dual color LEDs in there which would be cool to see lit up.

I just tried some clear t-glase that I had and everything was great for about the first 8 or so hours of printing. Then during the night sometime, the 2 front corners started slowly (from appearance) bending up from the plate (60C) and then everything from there up was hosed, like the ABS. I wasn’t getting layer separation with ABS (fan was off) or t-glase, just after time the corners would start to curl up just like the t-glase. This is the largest object, at least on the x/y plane, that I’ve attempted to print. It’s about 1/2" thick. I’m wondering if the edges (outer 1") of the bed is not as hot as the inner part of the bed, or just the material, or the size of the print, or combination… I don’t have enough experience to determine that yet.

Does anybody know the difference between n-vent and nGen? Same thing, different companies? I received nGen with the T6 and it printed the roctopus beautifully. Best print I’ve printed, until I tried to remove it and one of the tentacles just snapped off. Seems to be very brittle/no flex, which I can’t have. Maybe it’s a lot stronger when printed thicker. Those tentacles are pretty small and long. The material needs to be strong enough to take heated inserts and take quite a bit of torque holding pieces together as well as for mounting in the case.

Warping on plates and large area parts is hard to combat. The edge of the heated bed will always be less efficient than the middle of the plate. Covering the bottom of a Pelican case (assuming you’re using something like a 1300) can be difficult.


Here are a few ideas that have helped me:

  • Try rounding the corners. The different air flow seems to reduce warping.

  • At 3-4mm: lower the bed temp, use fan cooling and increase extrusion temps by a few degrees. ABS plate gets pretty rigid at about 3-4mm, keeping the bed at 110C can keep the material malleable cancelling out the benefit of being locked in flat. Lower the bed temp 90 - 100C. Start a little fan ~40-50%, to help mitigate compounded heat of each layer. Increase the extrusion temp by 1-2C to promote layer adhesion and mitigate splitting.

  • Try a little negative Z-offset in your slicer. This will increase adhesion… so make sure you have a good tool or designed in mechanism to get under the part for removal. Start with -.1mm. Look at the bottom of the print, check for a bottom that has little to no striatations from the extrusion. A flat surface, with little distinct striations and no elephant foot is would be ideal.

  • Break your battery holder down into smaller sections. Are you putting in the batteries vertical, side by side? Use a mechanical joining mechanism like dovetail joints to assemble.

  • A temporary enclosure… some folks have used blankets to trap the heat. In the winter I use a simple enclosure made from coroplast sheets to trap heat. Then disassemble when not needed.


    Hope some of the ideas help. If you post a STL, we might be able to give you more ideas on design or print tips.

Thanks for the reply and helpful suggestions. I think I have enough ABS for another try using them. It’s a Pelican 1450 case, and the part is divided in half and will be joined using the heated inserts. I’d be happy to send you the STL, I unfortunately just can’t post it in public. One of the corners that is warping is rounded, the other is 90deg. All prints so far have curled up, but only the 2 corners closest to the front of the bed. I supposed I could try rotating the part 90deg and seeing if that helps too.

Here are a few pics of the t-glase, the ABS looks pretty much identical though:

Whole thing (front lifting):


Left front:

Right Front:

I’ve tried asking that before and Jamie from ITWorks3D.com is the only person who really has answered my question about that. Basically what he said is that The INOVA-1800 Amphora-based filament is like a high-quality replacement for ABS and is super strong, high heat resistant, has low warping issues, and has no awful fumes. I think what he said about nGen and n-vent is that they are like good, better, best in regards to the quality of the Amphora used. I think it goes in order of n-vent (like a higher quality PLA), nGen, and then Inova-1800 (High quality ABS). Don’t quote me on that as i may have gotten the order wrong. nGen is made in Europe somewhere and nVent is made by a company here in Colorado in the U.S., so there is that difference too i think. But they all are interesting filaments with low warpage and low fumes and all very similar to each other.

nGen does seem stronger than ABS to me, but these Amphora-based filaments do seem to suction to the PEI tape and build table so they are a pain in the butt to remove, so that is probably why your octopus arm broke. I’ve heard some people say that using a glue stick helps these more suctiony filaments to be removed easier when they cool down then if you just use the PEI tape by itself, but i dont know if that is true for these, just something i had heard as rumor on the forum somewhere. Although try using a glue stick with your ABS, i think it has helped reduce some of my warping issues a little bit.

Thank you, and that makes sense. I was wondering why the 1800 was 2x as much as the ngen/n-vent. I did use the gluestick that came with the taz6 as the instructions said to use it with the ngen while printing the sample roctopus. I appreciate your input.

So you’re using the gluestick with ABS? I hadn’t heard of that.

Hmm… could try a tall skirt to prevent air from hitting the part as it moves in the Y axis. Maybe a 5-10mm tall skirt with 1-2mm offset from the part.

Post a pic of the bottom. On the TAZ6, you can apply Z-offset through the LCD. They removed the Z-offset gcode in Cura for some reason. If using some other slicer like S3D, the Z-offset should still be active.

I’ve been using nGen, XT, and HT, all from ColorFabb with great success for smaller enclosures that are subject to heat in the 60-100° C range. HT is the newest high-temp filament from ColorFabb and it has been living up to there descriptions so far. Lean more about it here:

http://ht.colorfabb.com/

Also, Makergeeks has some hight-temp PLA that can be annealed to and handle temps up to 250° F. Learn more here:

http://www.makergeeks.com/rasepla.html

Thank you all. I’ve purchased some Taulman n-vent, INOVA-1800 and ProtoPasta High Temp PLA based on what people have mentioned, and it finally arrived yesterday.

Last night I did a print with the N-Vent. Very impressed! The print was about 99.5% perfect - and no warping. I just have some minor adjustments to make as a few spots on the very top layer’s surface didn’t come out totally smooth and were a bit rough like finer grit sandpaper. But all lines were totally straight and my x/y/z seems pretty dialed in. It was a 16 hour print. There were also several tiny holes in some places where the the surface met a perimeter wall. I had turned my extrusion down a bit to 93% on the lower layers, so that might be why. I was using 25% infill, 230C nozzle and 60C bed. I also purchased Simplify3d and am loving it so far. Wonderful app.

Is there any chemical treatment that works with n-vent for smoothing like acetone does on abs?

Another thing I wasn’t too happy with was the adhesion was wayyy too good. I put a liberal coat of the Elmers All-Purpose Glue Stick that came with the Taz 6 like the suggestions say for n-vent on the lulzbot store and used the recommended temps. I have a very long thin blade spatula that I use. It’s .2mm at the tip and slowly thickens to .5mm for the 4" duration of the blade. It’s about 1/2" wide. I never pry upwards. I slip it under a corner slowly and slide it under the part until 3/4 of the blade is under, then slowly rock back and forth and work sideways as I’m working my way around the object. That was pretty tough. After about 10 minutes of work the part came up. There were 4-5 large air bubbles under the PEI. I heated the bed to 100C and spent quite a bit of time pushing them towards the edge of the film using a sponge and got them to work themselves out, and it feels flat and you could definitely feel a bulge before. I had lots of tiny bubbles like everyone else before, but I haven’t gotten these large ones like 1-2" diameter. I fear now that the good adhesion is gone between the glass and PEI that this will be a reoccurring theme now in those spots. Soooo… what can I do to prevent that? I seriously put like 2 thick coats of glue down from edge to edge. This one print is costing so much money in materials and breaking taz lol. Argh.

I also worry about replacing the PEI sheet. I envision it being like trying to put window tint on a car and not having the proper equipment to get all of the bubbles out. The first time.

Again, thank you all for the help. I’m getting there!

Not that i’ve heard of, but who knows.

My experience with n-gen is that with or without gluestick the stuff sticks to the PEI tape like gorilla glue everytime! I think i had read somewhere that the gluestick will actually help removal as opposed to no glue stick (believe it or not) if you try to remove it at 60 degrees. But perhaps i am just remembering things wrong.

Regardless that stuff sticks like crazy. You may want to investigate into adding spaces on the bottom of your CAD files like Lulzbot now has begun doing with their in-development files of the Lulzbot Mini if you plan to use an Amphora-based filament as it might help you remove them later. But that is just an idea. I have no idea if it will help or not.

An example of what i am talking about:
http://download.lulzbot.com/Mini/1.03/production_parts/printed_parts/lower_z_left_Mini/lower_z_left_v1.4.STL
lower_z_left_1.6_custom.STL (309 KB)

Thank you, I will check that out after my current print is finished, although it unfortunately might be my last for awhile. Is this similar to the raft feature of Simplify3D? I haven’t used that feature yet.

I’m trying the N-Vent again. I put 4 layers of gluestick down this time. Bed is at 58C. My entire PEI sheet is coming off. Not kidding. I haven’t even tried to remove it yet (still printing). It’s warped all over, large single air bubbles surrounding the entire print and the edges of the PEI are lifting up in places. I really don’t understand this as I’m following lulzbots suggestions for this material, and I’m really not very happy ATM. I’ll post some pics after it’s finished in a couple hours, before I try to remove it from the PEI. This keeps going from bad to worse. :imp:

Well I contacted lulzbot support first. They were kind enough to point me to where to purchase a new PEI sheet (out of stock) and a link to the instructions on how to install it. They couldn’t offer any possible reason why this would happen, and suggested to use more glue. I’m not sure how more than 4 layers will help, and not sure how having more glue would prevent the PEI from forming large bubbles and lifting up. The bed temp wasn’t even that high.

So, pile on another $40 in wasted filament and a $45 PEI on top along with further delays on this project and not knowing what I did wrong or how to fix/prevent it. I followed their instructions. My machine is almost perfectly calibrated using 30mm cube (within .01mm).

Here are the pics…

Here’s what it looked like from several angles before I tried to remove it from the PEI

Front View:


Right Side of bed:

2 pics of the left side:


Here’s the bed after removing the part:

And finally a pic of the bottom of the print. I believe the first layer was pretty good. I watched it go down and the top of the first layer was very smooth. I haven’t removed the glue yet so it still has the whitish film.

Bed temp was 58C, Hotend temp: 240 and using black Taulman N-Vent filament purchased from lulzbot site. Before I started this print the bed looked normal like the first inch or so of the “front view” pic, with just a lot of very little bubbles. Any suggestions/opinions here? Thank you!

I have printed a fair amount with n-vent without experiencing the PEI delamination that you had. It is one of my favorite materials. I have printed mainly with the n-vent clear material. But some with the black as well. I have not printed an object as large as the one in the picture though. I normally use only one or two layers of glue stick. The brand I am currently using is Schoolastic. It seems to work OK.

The recommended printer bed temperature is 60C. I know from other experience that the PEI adhesive is pretty soft at that temperature. I ruined one once by removing an ABS print from the bed at that temperature. The PEI peeled up with the part and I learned not to do that.

From what I have read on multiple forums, heating the bed is intended to help the part adhere to the bed. With n-vent, adhesion is not a problem. Im wondering if we could print at a much lower bed temperature when using n-vent and avoid stressing the PEI adhesive when it is soft.

Im going to try printing it with the bed temperature set to OFF and see what happens.

I added 1.5mm tall/wide grooves to the bottom of the print that were spaced out 3mm. So it went 3mm blank, 1.5mm contact, 3mm blank, across the entire bottom. That helped immensely by reducing surface contact. The bottom of my part is not seen so this was acceptable. I appreciate everybody’s input.

Just still not sure how the PEI could come off like that. I tend to think the 3M adhesive wasn’t very good due to how easy it was to just pull it off without freezing, etc. I used to be in electronic manufacturing and we used the same 3M adhesive to affix clear plastic sheets over electronic control panels. We used that stuff by the tens of thousands of square feet. Occasionally you’d get a batch that wasn’t very strong or had minor defects where the adhesive had balled up a little bit which made it impossible to make them totally flat when putting on a surface.