Trouble with printing

Hey looking for general help…only been printing for about a month. Generally I’m printing cookie cutters…first few weeks were nice and easy. Now it’s nothing but problems.

I can’t seem to get the cutters to stick to the bed, and when I get them to stick I get 75% done the print and the filament stops going through the extruded. It’s done this on at least 4 prints now, that includes filament change.

I’ve tried two different types of filament PLA and Petg.

Any tips for a newbie?

I thought the hardest part was going to be designing the cutters lmfao fusion 360 was a breeze now I just can’t seem to print!

Greetings, and welcome.

First, some questions: what printer and what build surface (glass, magnetic mat, steel sheet, carbon fibre)?

Without an answer to the above, I’ll tell you what happened to me (having started in November) but you have to keep in mind that if your printer is different, some of what I suggest may not apply in quite the same way.

First off, I presume you are aware of the vital importance of tramming (“levelling”) the bed? I have always found that a single sheet of printer paper is good enough to get the spacing right, although others swear by post-it notes (apparently thinner), or mechanic’s feeler guages (definately more precise).

I also presume that you are measuring the the height at all four corner and in the middle of the bed. If you don’t do that, you can have a case where a print starts to stick nicely at one corner/side and starts to lift off on the other, because one side is set up correctly and the other wasn’t.

Moving on… I bought a Creality Ender 5 Pro, which has a magnetic bed. It worked beautifully at first, but after a few months of scraping prints off, the surface, which initially had a texture, started to get smooth in spots. I ended up replacing the bed, which solved the problem, but of course it keeps recurring. I later switched to glass plates, which printed beautifully, but which was not borosilicate glass. That type of glass contains boron-trioxide which significantly lowers the glass’ thermal expansion. Those sheets worked for PLA, but when I tried printing higher-temperature Polycarbonate, they shattered. I now print on Carbon Fibre which has the surface finish of glass and so far hasn’t had any problems.

So, your problem could partially be a worn build surface.

The one negative thing I can say about carbon fibre, is that PLA doesn’t stick well to it at all. I have to use a thin layer of glue stick, but then that layer will last 6-10 prints before needing to be renewed. Also, if you try a glue stick, absolutely go for Elmer’s. It doesn’t have to be the purple stuff, which worked fine, but the slightly cheaper “all purpose washable gluestick” literally requires me to hammer the spatula (that came with the printer) at the bottom edge of the print to get it off. I have no problems with adhesion now. By the way, stay away from the Staples house brand glue stick - it’s absolutely useless for 3D printing.

So a washable glue stick may solve your problem.

Be aware that filaments are absolutely not created equal. Different brands, and even different colours within the same brand, can require printing at different temperatures. Filament can be finicky.

I’ve never tried PETG, personally, so I can’t comment on it.

As for filament that isn’t going through the exturder, this could depend on the model of printer. Some printers have plastic, not metal, extruder motor assemblies. The plastic ones have a well-documented history of cracking under the stress. When they do, the can no longer grip the filament as tightly as they should. The symptom is that the filament randomly stops moving.

I’m presuming here, that you’ve already checked, visually, to confirm that the extruder is, in fact, turning? I actually printed an extruder “wheel” that pops on the end of the extruder shaft and gives me a visual indication that the extruder is moving, even at a distance.

If the extruder isn’t moving, it could be a loose cable. My style of printer isn’t prone to this, but printers that have the extruder mounted on the carriage are obviously going to be moving the extruder cable along with the carriage and that can be enough to start wiggling it loose over time. Check your connections if that applies to you.

Overheating of the extruder motor or the extruder motor driver (on the controller board) can also be an issue, but I doubt that cookie cutters are taxing the system hard enough for thermal issues to arise.

Another possibility is the tension on the extruder arm. That’s the arm that you squeeze to load a filament. The tension comes from compressing a spring that is pre-stressed by a screw. That screw can work loose over time, reducing the pressure on the tensioner which in turn reduces the grip on the filament.

If you’ve been doing a LOT of printing, it’s also remotely possible that the extruder gear itself is grinding down, although that usually takes months to years.

As a newbie, I would also highly suggest you visit Teaching Tech’s calibration site and read every page starting with the introduction. It will take several hours to complete all the steps, but you will end up with a well-tuned machine when you’re done.

https://teachingtechyt.github.io/calibration.html

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calibration is very important. But before doing anything lego suggested, having printed Petg (food grade) cookie cutters myself, are you using a brim? The contact edge of a cookie cutter is quite small and you really need the brim. Before you tinker with glue and tramming (assuming you can get regular prints done) try printing with a brim I use about 6-10 mm for a cookie cutter. It has such a fine edge usually.

You still (likely) will need to calibrate the printer but I am assuming you have done so already when you got it. this is usually part of the instructions. It could just be the contact edge is too small.

I also would try PLA first some find Petg a bit for difficult to print. PLA and a decent quality will give you a leg up.

On a second side note, food grade filament is available it is acceptable for single use. One batch of cookies and toss the cutter. If you wish to re use it over and over you need to concern yourself with filling the layer lines with something food grade and smooth. It is not possible to clean between them completely and will leave a place for bacteria to grow. Depending on the dough this could be a real health risk.

To a lesser degree the metal of the hot end also is a concern. One of my printers is actually set up with a stainless steel nozzle heat break and a bowden tube so no unwanted contaminates are present. I print cookie cutters with a food grade filament and toss them after each batch of cookies. I just reprint them over and over as I need. I found it too much effort to mess with epoxy coatings sanding and finishing to make the print food grade and safe.

I use a food safe filament, it comes with a certificate of compliance to be completely food grade. Remember most pla and pets are food grade materials but the various additives and pigments are not at all. (or potentially)

These are just examples of what I am speaking about.

Remember it isn’t ok to have layer lines. You need a food grade coating to fill them in. If you go this route true food safe filament might not be necessary as you will need to fully encapsulate the print in food grade coatings.

I don’t bother so for me food grade filament and one time use.

I think everything have been said by my two friends above! :slight_smile:
If you want a good trick to reuse your cutters, use a piece of saran wrap between your cutter and your dough… :wink: This will work really well for most cutters and will keep your cutter clean for the next time! :wink:

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I know it’s sacrilegious to question anything relating to food safety, but I do think it borders on hysteria sometimes. So let’s say some bacteria ends up on the cookie cutter…and you cut another cookie with it. Unless you’re eating raw cookie dough, that cookie is going in an oven at 400F for 15 minutes. What bacteria is going to survive that?

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The answer is I don’t know. I am not qualified to give that advise. Not the right flavour of expertise.

I do know that a cookie cutter printed in Food grade Petg washed in a regular dishwasher grows fuzz in hot damp weather. If the fuzz bad for you? I don’t know. Could bacteria transfer from on surface to another, I think so. Does that pose a risk? I don’t know.

I have had Salmonella poisoning, I understand that it means being doubled over with cramps and vomiting and diarrhea at the same time. I will not eat chicken that I do not prepare. Does that mean do I wash my BBQ grill every time, no I don’t. Nor do I wash the carrots from my garden, a little dirt is fine.

Am I going to suggest you eat unwashed carrots, no. Wash your carrots. Clean your grill.

I don’t wish anyone to get sick because of my comments. For the sake of a few cents I do not see the point myself.

OP my personal method in case you are interested, is: Once I decide to bake cookies (I usually have a reason to make shaped cookies) I pick the cutter shape open the file and print a new cutter. I then make the cookies take the cutter I made the last time. Cut my shapes and bake the cookies. By the time the new batch is out of the oven, the printer has made the replacement cutter. I wash it and clean off the skirt and back into the drawer it goes.

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The only point I was trying to make is that whenever you see any mention of 3D printing around food, people on Facebook go nuts. There never seems to be much consideration with what you do with the food afterward.

I would never eat off a printed plate for the same reasons I would never use a wooden plate/spoon/bowl (it was a thing in Germany) because you can’t sterilise the wood, but if the food is then going to be properly cooked, that’s different, but the Facebook crowd never seems to think that deep.

There are, by the way, two types of ways to get sick from bacteria. The first is where you ingest live bacteria which then grows in your gut. I think Salmonella falls into that category. Been there, done that, and it’s turned me off chicken ever since.

The second is where the bacteria lives on the food for an appreciable period of time and excretes toxic chemicals as part of its life-cycle. It’s the toxins that make you sick.

In the first case, you can make the food safe by properly cooking it. In the second, cooking will not help since you can’t “kill” a chemical.

In the first case the bacteria can be transmitted by even a brief contact with an infected surface followed by consuming it without the food being pasteurised (heated to a point where the bacteria will die, then held at that temperature to ensure the food is cooked throughout.

In the second case, the food has to be exposed to the bacteria for a much longer period of time to allow for sufficient toxins to accumulate to toxic levels. As I said, no amount of cooking will get rid of it.

Anyway, getting back to the subject at hand, that was a good catch on the fact that the adhesion might simply be because the cookie cutter doesn’t have enough surface area. I hadn’t thought of that.

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So I have an ender 3 v2, it has a glass bed….I have been using just a single sheet of paper for bed levelling, been using a brim (outside brim only) to help with adhesion, I did figure out a few things last that seemed to help with adhesion. I have the bed temp up to 95 but still a bit of warping in corners, (inner fine tipped). I managed to get through a print last night too…no ghost printing. Someone on here suggested a link to read, I will definitely check that out…ever time I solve one issue another one comes up. The print that I did complete looks like it’s full of cobwebs :man_facepalming:

When you see cobwebs, it usually means your nozzle temperature is too high, or you aren’t retracting enough. These things are covered in the calibration link I sent you. It’s easy to fix.

Lego no worries. I don’t actually have enough information to have an informed opinion so I fall back to caution.

OP try PLA, in my experience of printing quite a few cutters PLA stands up better. Proper calibration will help either but petg for some can be a pain in the butt, it does tend to be stringy if everything isn’t right.

It depends on what printer you are using it’s possible that you’re experiencing heat creep and minor jams at the moment you might need to take a look at your hot end