After struggling with warping for a long time, I thought I’d tried everything. Spray glue, glue sticks, blue tape, slurry, sacrificing chickens at a full moon, the lot. I recently ordered some Elmer’s Purple sticks as another straw grasp and Amazon offered me a 3M roll of blue tape, so I thought, “What the heck” and ordered it. Although I’d used blue tape (from my local DIY store) without much success, it wasn’t 3M and when the tape arrived I could see it was quite different from the one I’d tried. There was more texture to the surface, it was thicker, etc.
So, I tried a print yesterday and joy of joys, it worked. Not the slightest hint of warp, the print stuck to the bed completely. And utterly. After letting it cool, it took 10 minutes just to get the print and tape off the (glass) bed and a further 15 minutes to scrape/clean the tape from the bottom of the print; that stuff was welded onto the print.
So it seems I’ve gone from nothing sticking, to sticking far too much. I’m obviously going to experiment, but I thought you lovely people here might know exactly what the issue is and save some time.
Is the bed too hot? I’d been using 110C when printing straight to the bed using adhesive spray, is this too hot for blue tape? Does the first layer need to be thicker (so it’s not so bonded completely to the tape texture)?
Any ideas/comments welcome. At least the good thing is that the warp has gone and I’d rather have a sticking problem than wasted warped prints!
If you have glass beds, I highly suggest an acetone/ABS slurry on the plate. I use exclusively this on my Axiom, and have no curling whatsoever with ABS - I use natural ABS and shoot for a 10% concentration of ABS in the acetone. It’s not an exact science but I end up with a mixture that has the look and viscosity of skim milk.
I do think 110 is a bit warm - I usually start my plate at 75degC and drop it down to 60degC after the first 5-10 layers of the print. I do print my first layer thicker and slower than preceding layers so that might help. Do you have an enclosure around the printer?
Hi @Enza3D I tried slurry - and it looked like skimmed milk - but it simply warped as usual, peeling the slurry (now dried) away from the glass. It’s possible (likely, in fact) that I need to experiment with the exact mixture, but since this new blue tape at least definitely doesn’t warp, it seems like a more promising lead (and a lot less messy).
I use 110C for ABS, usually 60 - 70C for PLA.
Having just done another quick print, I suspect some of the problem may be the z-position. The bed is calibrated for the glass alone, so I’ve used a small z-lift to account for the tape (0.05mm) BUT I think this may need to be more, that the plastic is being forced into the soft tape, blending with it to some degree. I’ll try some more experiments adjusting the z-lift.
Hm, that’s odd. Was the bed hot when the slurry was applied? I wish I had any luck with blue tape, no matter what I do I can never get my ABS to cooperate on blue tape.
ABS, in my experience, really does not like being “squished” onto the glass like PLA does. So it is entirely possible your Z-position is a contributor. If you have an infared thermometer or the means to pick one up (not a camera, just a small guage, usually like $20 at Home Depot or the like), I’d also suggest testing the heat on your bed and making sure you’re having close to even disbursement of heat on the bed.
If you want a good print bed material, PEI has been the best for me. It has great adhesion and I no longer use any glue or sprays. It simply sticks to PLA and other material at operating temperature (70C for PLA). For ABS, you have to go higher to around 100C to 110C. As soon as the bed cools down, the part comes right off without any effort. There is another bed material called FilaPrint that is sold in Europe that people had great success also, but its a bit more expensive.
I would stay away from any contact-less IR thermometers. I did not have success with my IR sensor and getting reliable readings either because of the reflective nature of the print bed material or the location where I want a reading is too small. The best tool I used is a K-type thermocouple thermometer. You can find them in Ebay and other sources for less than $10 and they work great. You can tape them to the bed or even hot end with kapton tape and measure directly and compare to the temp sensor reading from the 3D printer. Most of the time, you will find out the actual temp reading is different than the sensor. The sensor may be located at a distance from where you want to measure the actual values. I sometimes adjust my bed temperatures until I get the correct reading on the top surface.
It revolutionised my printing experience. Prints stick, no maintenance to the build plate apart from the odd wipe down with alcohol, prints release easily… it’s amazing.
It’s the best upgrade you can do to your printer, bar none.
Once you have a PEI bed, then the next upgrade is an enclosure, but that’s harder to achieve for most people. It really helps with warping though.
Ok, so PEI. Any particular brand and place to get? How does it work over glass? I am thinking to try it on a glass plate I use so the whole thing can be removable.
You may get a reading, but you don’t know if the reading is accurate. The thermocouple thermometers are extremely accurate. I have four different meters and they all read withing .5 degrees difference without any calibration.
If you are trying to detect a temperature on a relatively small area, you will not be able to accurately focus on a small area with most IR sensors. I tape the thermocouple specifically next to the nozzle under the hot end block and get accurate results. Sometimes reflective surfaces like glass or aluminum does not provide good results due to the emissivity of the material.
A few 3D places stock it, and you can also get it from Amazon. It doesn’t really matter what thickness (thinner is cheaper). You also need a sheet of 3M 468MP adhesive to stick it down. https://www.amazon.com/dp/B0013HQ7B0/ref=biss\_dp\_t\_asn
I was exactly in your shoes - printing PLA and ABS and nothing stuck properly. Then i had to disassemble the print bed for an unrelated reason, and discovered that the power cable for the heated bed was being kinked and was clinging on only a few strands. I re-stripped the wire and resoldered it. Now it works with no problems whatsoever.
my two bits: test your bed temperature, check your PCB connectors and wire connections
If that’s not your problem, get a PEI surface. PEI is absolutely amazing for ABS.
If you have a heated bed, look into getting a PEI sheet and stick it onto the glass. No more glues, no more fuss with cleaning surface. The parts stick down to the bed and will not let go. Only way to have it release is to let the bed cool down and the part pops right off. I literally wipe the surface with isopropyl alcohol and I’m ready to print. When its done, I turn on a small fan to blow on the part and wait until the bed cools down and the part comes off easily. You can speed it up by spraying some alcohol to help cool it down quicker. I used to take the print out and put into freezer. Now, I spray, wait about 5 minutes to let it soak in and the part comes out like butter. The excess alcohol on the bed, I just use it to clean the surface and I’m ready for next print.
I don’t know how big your printer bed is, but here is a link to a 12" x 24" x 0.032" thick sheet of PEI. You don’t want it too thick since the thicker sheets are more expensive and its not flat. The .032 thick sheets are perfect since you get decent thermal transfer and its thick enough to be durable. You can cut the material to fit a round bed with a sheet metal shear or a heavy duty scissor. Note, the size of the sheet is usually about 1/4 smaller than the stated size. My sheets came in at around 11.75" x 23.75".
Just use the 3M double sided tape to mount it down. I find it easier to put the sheet on the PEI first and carefully lay it down on the bed starting from one corner. Work slowly since if you screw up, the 3M tape is a pain to remove. It will change how you print parts on a 3D printer forever.
No more worries about glue or print bed tape. One thing you do have to watch out is the sheet is soft. You have to make sure the bed height is set right or if you go too deep, you can gouge the surface or leave an imprint. All my prints have a faint outline of 20mm cube on the bottom now (LOL). I had a bad day and didn’t pay attention when I started the print. At least now I have a reference point under the part to know the part size.
Thanks, I’ll check it out. I have been holding off due to cost since hair spray works pretty good overall. Just trying glue on ABS for the first time. First print was promising until a power blip killed the print!! Go figure!
Its actually not that bad in terms of cost. For me it was under $45 and it completely changed how I print. I used hair spray before and now I have two full cans collecting dust. The only thing I buy now is 90% pure isopropyl Alcohol from Walmart. I use it to clean the surface and to cool the part after a print. I can’t imagine a better surface. I tried FR4 based solution like PrintBite, but I was not impressed with the holding power. It holds well at temperature and the part comes off when the bed cools down. However, I still had issues with lifting on corners on small and large parts. I don’t trust it to hold my parts especially for long prints. I have full trust in PEI since there is no way for me to take the part off without damaging the bed when its heated. Once it cools down, you can pop the part right off with no effort. The only issue I have with PEI is that its transparent to IR light, so I have to coat it with black paint in order to use my IR height sensor. Other than that, its awesome.
Sounds good. I have some stubborn ABS parts that are large and a lot of infill (still tinkering on that) that love to lift at the corners after several hours.
From what I have read on Printbite it is not great with ABS so I wasn’t going to try it.
Just a quick update. I’m getting reliable good results with the blue tape now. Getting those results seems to be mostly about the z-height of the first layer. I’m still calibrating the bed to the glass surface so the blue tape reduces the gap. Print with too small a first layer and there isn’t enough material laid down to form a good bond for the next layer (and you get all sorts of uneven blobs). Print with too large a first layer and the ABS doesn’t adhere well to the tape.
I’ve done half a dozen prints now where there was no warp and in all but one the tape came away cleanly from the model. In the one case where it became stuck to the model (this may have been because I allowed it to cool right down to cold room temp, about 11C overnight), it was easily removed after soaking in warm soapy water.
The prints are still sticking quite firmly to the bed under the tape so need careful removal with a scraper but they’re not “welded” to it like they were with my first attempts with this tape.
So, in summary, for me it seems to be:
1. Use the right blue tape. I’m using the 3M 55mm wide version from Amazon.
2. Warm the bed before applying the tape (to about 65C so it won’t burn you). Applying the tape to a cold bed means you get gaps between the tape strips as the bed expands (and possibly reduces the tape adhesion).
3. Get your first layer height right. I can’t give any examples because I suspect the “right” height will vary from printer to printer, material to material, but essentially if the nozzle is too close to the bed/tape you get a poor first layer and/or the tape welds itself into the print and to the bed, if it’s too far away it doesn’t stick well (to either the bed or the model).
The PEI bed sounds interesting, and I might well give that a go as well. Although the tape is working, it adds time and “fuss” to the print process I’d rather not have (and is of course an ongoing expense, not a one-off, albeit quite a low one).
I should be trying the PEI this weekend. It is supposed to get here tomorrow. I am also going to run another glues stick on glass test. The last one was going good until power interrupted the print!
I was doing a glue stick test and it was going good until power killed the print. Going to try another starting tonight. I had a lot of infill on my part 50% for strength. It is two pieces that bolt around a pipe like a clamp/bracket. I think if I do even more shells I can reduce infill since many shell layers around the bolt holes should give good crush strength.
Well, this whole PEI experiment was a huge waste of money. I haven’t even been able to print with it. As the bed gets up to temp for ABS (100c) the PEI starts to curl and peel up all around the edges. The interesting this is the PEI sheet was perfectly flat as I installed it.
You need to install with the 3M 468MP double sided tape. Other types of adhesive can not handle the temperature without delamination. You can’t install the sheets on top and use clips either. It has to be bonded down to the glass with the tape to work. What type of bed surface are you using? Glass? Did you verify the surfaces are clean before you stuck the PEI sheet on it and verified all the bubbles are removed?
Here is another thing to try. Heat up the bed and put another sheet of glass over it and apply some weight over the bed to get the sheet to stick down. You will still need to put in clips along the edge to hold the glass plate down to the bed surface and it would go over the PEI sheets.
Thanks for the info. I bought exactly what I needed as you listed I believe.
I am bonding to boro glass and it was clean. A good scrub and rinse in HOT water, air dry then washed with alcohol and air dry.
I bonded the mat side of the PEI and as it heated it lifted and curled bad. I flipped it so the shinny side was down, which I really want up, and it is sticking for now.
I am going to try another later and this time heat the glue once install and then weight it. Weighting it should matter since this 3M glue and PEI are not compressible but stick by contact but it’s worth a try.
I have my PEI mounted on Boro glass and also an aluminum disk for even heating also. Make sure you wipe down the surface of the PEI also and it should help. The PEI is not compressible, but the glue underneath is. Its relatively thick and the material will press down. The trick with another layer or glass and some heavy weight is to ensure that its bonded at temperature. You have to heat the bed while you apply the force. I’m glad the shiny side is working a little better for you. You might had some trapped bubbles on the first try and that expanded enough to lift the PEI sheet. Keep us posted.
Hi @ShadowX the PEI sheet I’ve ordered apparently is self-adhesive - are you saying I should use the 3M tape instead of this self-adhesion (it’s 3M - you can see the logo in the picture)?
I was also intending to put the PEI directly onto the bed - is putting it onto the glass a better idea (actually happier to do this as it’d make removal/replacement easier and allow me to use multiple beds).
I don’t know what type of adhesive they used for your PEI Sheet. If its 3M 468MP, that is the preferred material. It will retain adhesion at least up to 100C on a print bed. Some of the other adhesives may not be rated for the high temperatures. The 3M material is usually labeled on the backing tape. If the sheet already has the backing tape, you should just use that for now. If you find out that it has problems at higher temperature due to delamination, then you should remove the PEI and use the 3M tape.
Sticking directly to glass is fine. You may have to raise the temperature up slightly or wait a bit longer until the top layer gets up to temperature. Compared to glass, you can actually use a lower temperature for PLA than plain glass. At around 40C, my print is already sticking well. I used a thermocouple thermometer to measure the actual bed temperature on top since I have a high power heater and the thermistor is on the aluminum heat spreader. I have a old kapton heater layer, glass, adhesive, and then the PEI sheet. Its not the preferred method, but its a pain for me to get the old kapton heater off so I left it there.
Seemed like a good deal as it’s big enough to cover the FF Pro bed twice. If you look at the close-up photo you can see “3M” branding on the back. Should arrive tomorrow or the next day (I ordered the last one, hence the long delivery time shown now on that page) and I’ll report back once fitted and tested.
OK… another update. I’ve just completed my first print on my new PEI sheet and… it’s “OK”, but not perfect. There was some very slight warping to one corner of the model, not huge, but enough that I can’t send it out to the customer. The print was ABS, bed temp 90C, absolutely no adhesive at all, so it was a tough test.
I’m now printing another part at 100C bed (my normal ABS temp, I reduced it in the first test as a… test) so we’ll see how that goes. I’d rather not use any adhesive, but I’m thinking a tiny spray of adhesive will probably make it 100% warp free.
Anyway, so far it’s pretty good and I’m sure will be excellent for PLA, but it’s certainly not perfect first time…
You have to bump up temp for ABS. With all the layers of thermal resistance of glass, adhesive and even the PEI, the top of the bed may be 15C less than the temp on the heated bed.
I gave up on it for now. The expense and effort was not worth it. It still isn’t working well for ABS. I get much better results with hair spray or glue stick on glass and the effort really is minimal.
I need to get thinner glass to try again with mounting the PEI or make yet another shim!
I might have a solution for you There’s a 3D printing adhesive called Magigoo that works pretty well with heated beds because it sticks when the bed is hot and when it cools it releases the print almost by itself. If you’re printing ABS or PLA I’m sure it will do just fine. you can find it on magigoo.com
