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Hii there,

I have a Velleman K8400 and after a tonne of issues, I could finally start printing.

The first few prints worked out horrible (I had to throw away the first few layers for a few times).

Then, I managed to get one working print (the quality and strength of the thing was horrible, but at least I got progress).

Then, I decided to print out something else.

It started horrible, but for some kind of reason, the final product was “okay”.

Today, I wanted to print out something I found on Thingiverse (a little fidget spinner), but I can’t get it to work.

For some kind of reason, the first layer doesn’t properly stick to the print bed. (the first two layers are the most important as far as I know, and can make or break your print)

I’m using a non-heated bed with some painters tape (the previous owner from who I got the printer - for free luckily - managed to damage the BuildTak cover very badly, making it pretty much unusable).

I did the usual print bed levelling, with the little sheet of paper (which is really hard to do because literally, everything gets in the way, the frame, the printhead itself etc.).

looking at the print bed from the front, I see a small bend, but I’m not sure if it’s just my eyes, or that it’s actually bent.

Can somebody give me some directions on what I might be doing wrong?

I searched a bit on YouTube, Google etc. but I couldn’t get any good answers for my situation.

I’m new to 3D printing so that’s why I decided to make my own thread :slight_smile:

I myself think it might be a feeding issue (because this printer had tons of feeding issues before that where all caused by grinding of the filament)

what do you think?

Cheers

1 Like
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Hello,

I am an owner of a K8400 and you need to adjust it.

1/ Very important, the oil put oil on all metallic bar properly. If you hear 1 step problem with the engine it is the problem.

Real Oil no WD40 !!

2/ Clean the captor. You have 3 optical sensors, If they are dirty the printer don’t know where is the Nozzle when it start

3/ The most important part is the adjustment of the platform. The distance between the nozzle and the platform is 0.2 mm wich is a double fold of a paper for a printer.

4/ Then like on all PBS / PLA printer you need to clean the nozzle often

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Hi mate. First of all. I feel your pain. My first printer was a K8200 that I purchased and assembled. The first couple of hrs I spent printing were horribly frustrating (to the point that I almost tossed the printer in the trash) but trust me, it gets easier and more enjoyable as you get some experience. I now love my K8200 to death (I’ve had it over 2ys now) and have built much more advanced/newer printers since. But my old K8200 has a special place in my heart. The single most important part of a print is first layer adhesion. If your first layer doesn’t stick. Stop, and start again. What material are you printing? PLA I assume (with no heated bed)? PLA will stick to blue painters tape (it’s the waxed layer that it sticks to so apply new tape regularly and don’t wipe it down with anything before printing). If you are really struggling with adhesion to painters tape, try PVA glue instead (google the specifics, I won’t go into them here) Bed levelling is a hassle (especially if you have a warped bed, as it sounds like you do) invest in a borosilicate glass plate to alleviate this (again google is your friend) eBay is good for cheap plates. Correct bed levelling is again critical to having any chance of success. It’s a hassle, but take your time as once it’s done, you shouldn’t have to touch it again. Print the first layer SLOW! I print my first layers at 15mm/s (10mm/s for PETG or other copolymers). This really helps with adhesion. Try bumping the temp of the extruder (5deg or so) for the first layer. This can also really help. Get to know your slicer settings (not sure what software you’re using) I’ve settled with a repetier host/cura combo. Works for me, but it’s really a personal preference thing. Also. Head over to the Velleman forum and start reading the posts there. That is where I gleaned much of my early knowledge when I first started out. There will be info specific to your printer, and the community is polite, and very positive and constructive. Good luck. Please don’t let the frustration get to you. You’ll be surprised how quickly your prints will improve as you get to know your printer better. Don’t expect perfect results over night. But at the same time, your K8400 is a perfectly capable printer, capable of excellent results. A couple of simple mechanical and software tweaks, and you’ll be printing like a pro in no time. My K8200 is archaic by modern printer standards. But my prints are universally praised when I present them to fellow 3d printing enthusiasts. To the point that many do not believe that they were printed on a K8200. While I have modified many parts of my printer and upgraded others. The key to the quality I achieve is simply settings (software/slicer settings) Find some simple test pieces, simple calibration cubes, the Marvin key ring, 3dBenchy ect (google thingiverse). Hope this helps a little. Kind regards. JT.

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I have had loads of problems with my Velleman printer including the ones that you are having. For sticking issues I finally went with a glass plate which I hold to the original bed with 4 small bulldog clips and I coat this with a strong hold hair gel. this works for me most of the time. For the feeding issues I finally gave up and fitted a E3D extruder which has not given me any trouble. It irritates me that I had to buy extra parts to get the printer working but it was worth it to ease the frustration (and cost of failed parts).

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Hi,

Quite a few good responses here already, so I’ll just add a few of my own & some notes that might be helpful… :slight_smile:

As mentioned earlier in this thread, you should try to visit the Velleman K8400 support forum. You’ll need this link: http://forum.velleman.eu/viewforum.php?f=56&sid=8e7c7cc706b3d436af93d3e755323b75

Secondly, this WIKI describes a various fine tuning & problem solving methods - I’d suggest to have a look there too: http://www.k8xxx-3dprinters.crimed.be/w/index.php?title=Vertex\_K8400\_3D\_Printer/nl

The build manuals might also be interesting: Vertex 3D printer (K8400) - Whadda - Manual Platform - Category

Use a thin type of oil (sewing machine oil works well) to lightly (!) lubricate all axis when starting a print job. Also, make sure all axis are aligned properly: the wiki describes how to this.

The BuildTak sheets work quite well for this printer, but it is subject to normal wear: if the current sheet is worn or damaged, you could consider just to replace it? It’s just a sticker on a normal sheet of glass. I keep a few of them on stock myself: for wearing out, but I also damaged one once when taking a part off. But there are various alternative solutions to prepare the build surface - pick whatever your preference is.

As mentioned, the nozzle should be close to the bed: about 0.35mm is the recommended standard (deviations to this height, as mentioned in this thread, will be based on personal experience: I actually still use the 0.35 height). Using an 80 grams A4 sheet, folded 2 times, should get you the right distance: use this as a feeler gauge, if you don’t have a real one.

Also, the build plate needs to be quite flat: with a print height of 0.35mm, you only need to be off 0.1 or 0.15mm & you’re out of reach for the material to stick to the build plate… So, if you’re not sure if the sheet is flat, take it out of the printer & put it on a 100% flat surface. If in doubt, go to a CNC machining company & ask if they can check it for you with their height meter. If it’s bent, it’s best to toss it & buy a new one.

There are also some recommendations on PLA temperature & flow parameters for the extrusion process - but I’d look into that later, if I were you. You have bigger issues to look at, for now. :slight_smile:

Hope this helps.

For what it’s worth - I have my K8400 about 1 1/2 year now & it works like a charm. With the right service & calibrations, yours should give you good results too.

Best of luck with your printer & keep us posted of your progress. :slight_smile:

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Try printing with some more temperature, or some more feed rate or even some less space between noozle and bed (finetuning at the back screw). Also confirm, that your bed is cleaned of dust and any fat…

I also got this printer - and it got me grey, until right setting was done…

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Hii there,

what temperature would you recommend? I’m at 205 at the moment (which goes down to 200 after the first 2 layers)

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Hii there,

Right now I have the glass plate with some painterstape.

It does do the trick in some cases, but it doesn’t anymore for some odd reason.

Buying a new extruder is not possible for me at the moment, but I’ll make sure to keep it in mind!

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Hii there,

I’ll go do the stuff you said :slight_smile:

It’s very detailed so their has to be something I can improve.

I’ll go print a Marvin Key Ring tomorrow when I wake up and hope I can figure it out.

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1. I use Sewing Machine oil. (I used to be a bike mechanic and lockpicker, so I know that WD40 will cause more issues than it will solve) Seems right? or should I try some other oil as well?

2. captor? where can I find it? because for some kind of reason, it does know where the nozzle is when it starts (even when I place it in the middle of nowhere). Ofcourse, not when I move the head by hand (so physically moving the thing with brute force).

3. would a regular old playing card do the trick?

4. I clean the nozzle every monday right before the first print. or do I need to clean it more? I also unload the filament before I shutdown the printer.

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Hii there,

the metal plate the glass plate (where the actuall printing is put on) lays on is bend (or so it looks to me. using a leveler to measure it)

Unfortunately, I can not find a replacement for this (the glass place is straight, but get’s bend slightly because of the metal plate underneath it I guess?).

Any suggestions on that?

I will try to follow the rest of the stuff you and the others said.

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I have no experience with your model, but this may help:

Use a rigid piece of glass (3-4mm), do a manual calibration for all corners (or above each adjuster) with a piece of printer paper (0.25 works for me), and use two layers of UHU Stic (German Glue Stick) on the glass for all types of plastic. ABS requires 90+ C, but PLA does not require heat. Good luck!

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Hi,

I purchased my printer at Okaphone in Groningen - they tend to be able to supply spare parts too. A link with the most sold ones is here: OKAPHONE - 3D Printer onderdelen (Vertex)

I’m sure, they could replace the bent bed plate too (the order code you’d need is: K8400-BP).

Hope this helps?

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Replace the painters tape every couple of prints (don’t need to rectify whole bed, just the area you’ve printed on) because it’s the wax coating on the tape that the print sticks to. After a couple of prints the waxed layer would be compromised.