Kossel with heated bed - how is it possible?

Hello together,

I've built a mini-Kossel and I've got some serious problems getting the PLA to stick on the glass bed.
After reading in the forums, I've purchased a heated bed MK2b. Long story short, it doesn't fit into the Kossel. It's just about 5mm on each side, but it's 5mm too much. I've already ground some of the heatbed off on both sides (almost up to the copper layer), but it still doesn't fit, the belts are in the way.

So, how did you solve it? Or, if you all are printing without heatbed, just gimme a hint how you got the filament sticking, I can't get it to work...

TIA
stahlsau aka Jan

You can try to put 3M Blue Tape on your glass bed.
PLA should stick properly.

Thanks, I've ordered it already. I just wondered if nobody uses a heated bed with a kossel, it seems unlikely to me. Or, if i would use a one size smaller heated bed, it would steal too much of the build area. There are quite some people using a kossel, i guess someone has a tip for me, i'll wait ;-)

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stahlsau

i guess someone has a tip for me, i'll wait ;-)

If you get impatient, you can try the Search function.

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ddseeker
If you get impatient, you can try the Search function.

Well, I did. Impressive 11 results for "kossel heated bed", one of them is this thread, none of them answers my question.
2 results for "kossel heatbed", not much more for similar searches.

Searching for Rostock or similar machines won't help, since the build-area is much larger there and the heatbed will fit out of the box.

my comment was not intended to be difficult, it is just I don't own a Kossel or a MK2b and I am unable to help other than suggesting to search
(encase you don't get an answer to your question)

What I would do if I did own Kossel...

First: Go to Kossel - RepRapWiki page

Second: Scroll down to the Frame section and click the link 1x Borosilicate glass print surface with 170mm diameter

Third: (now on Trinity Labs site) I would click on the Shop link in hopes to find hotbeds to fit Kossel

Forth: I would notice the 12V 120W Kapton Heater - 160mm Round

Lastly I would note in the product information, "This is an ideal size to fit our 170mm round borosilicate print surface"

with this information I would measure if it is worth buying this and taking a loss with the MK2b
Wait, you can use the MK2b for your second and bigger printer you will now have to build! you just can't have that hotbed sitting there collecting dust now!

(think this post might better answers your question, "Kossel with heated bed - how is it possible?")

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ddseeker

(think this post might better answers your question, "Kossel with heated bed - how is it possible?")

yep, it does ;-)
Thanks for the link with the round heatbed, didn't notice there are round ones around.
Anyways, it hassles me having the hotbed here and not beeing able to use it, I'll investigate further.
And I don't give up yet, I guess there are at least 25 kossels on this forum, at least one of them must've found a solution. Damn, if i had known, I had ordered the horizontal beams 10mm longer, that would've been sufficient...

Two quick notes:

First off, the search function automatically limits searches to posts in the last 30 days, so if you don't find what you're looking for, do an advanced search and broaden the time.

Second, I've had my eyes on that bed for a while, but there has been some significant problems with TrinityLabs, see here: [forums.reprap.org] I think some people have had good experiences, but a lot have not. Just a little "buyer beware."

Best of luck!

Fwiw I ordered the 170mm glass and 160mm kapton heater from Trinity and it arrived within a week. Haven't had a chance to play with it yet but it's just a giant resistor so hard to go wrong?

Aaah, that's good to know. The issue wasn't the actual product, it was with people ordering stuff and never receiving it. I guess it's a small enough order I can risk it.

FWIW, I ordered this heater last week and it came in a few days. It works great on my Kossel Air and immediately fixed my curling problems for Simpson parts.

It was super easy to install; just had to crimp 4 wires and add housings, apply the sticker-style heater to the boro glass, and enable the thermistor in Marlin. However, a regular-size Kossel Mini may require a few cable extensions. Mine is 500mm tall and the wires just barely reached the electronics at the top.

Thanks for the input, I've bought a kapton-heater now from a different source, as I'm not from the US it would've been too expensive with shipping and so on.

Hi,

from where do you got your heater, because I am not located in the US, too. Maybe I will get the glass plate from there?

Thanks,
Subo

Hi,.

i searched for kapton-heater or silicone-heater or something on ebay, then i found it.
For the glass, i bought a spring-form with a glass bottom (really, for baking cake ;-)). It cost about 15€ or something, its round, heat-resistent, flat...everything i needed.