bare aluminium VS anodized aluminium heated bed?

Hello everybody,

This is my first post since I entered the incredible world of 3D printing some months ago
I have a self-sourced mendel90 and I have replaced the glass sheet that I was using with an anodized aluminium plate.
I wanted to try aluminium because although I had really great success in making ABS stick to the glass using glue stick, I had to replace the glass almost each time I was printing something because glass shards where removed. On large parts a large portion of glass would even come off. But now that I use aluminium, glue stick is not working at all, I've switched to hair spray and my parts warp all the time, even if I use a brim...
I was wondering if the fact that the aluminium is anodized could explain that glue stick is not working at all? If so I guess that removing the anodized material could help?
Does someone encountered the same problem?

Which is the thickness of your aluminum plate? It sound like you have the 3mm plates that Chinese places sell?if so get rid off it, it might not be flat and or warp on heat, get a 1/4 inche aluminum tooling plate.

If you want to keep using it just sand it with fine grid to remove the anodized coating

Thanks a lot for your answer!
You guessed it right, I'm using a 3mm aluminum bed I got from aliexpress for 8€. I'll sand the coating and post an update to get you guys updated about the effects.
You are perfectly right about the flatness of this bed, I noticed it is not perfectly flat while calibrating the bed. I do not use a probe to correct for this. Do you have any advice about where I could get a good aluminium sheet?

Depends where you live. Look for aluminium suppliers in your area, you need milled flat tooling plate. I bought mine from www.aluminiumwarehouse.co.uk

it's the ecocast plate. Not too expensive either I thought, although postage is not great. Fast though, and well packaged so I guess I can't scoff too much.

[www.midweststeelsupply.com]

I bought mine from this supplier. USA

I use a layer of clean kapton tape on my cast aluminum tooling plate bed. ABS, PLA, and TPU stick well. When I say clean, I mean wiped with acetone before heating.

When printing PLA, I usually just put on a layer of blue painter's tape and print at room temperature. You can start printing as soon as the hot-end is hot and there's no waiting for anything to cool off before removing the print.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

Hi guys,

Thanks a lot for the suppliers information. I just checked the prices for the one you provided Origamib since I live in France, I thought the prices would be much higher, I'm pleasantly surprised :-)
Here are the results of the experiments I did yesterday with ABS (from eSUN) on aluminum on my mendel90:
So after having sanded the plate to remove the anodized substrate, I tried again using glue stick and this time instead of not sticking at all it sticked a little bit, but not enough to make a successful print. The difference in adhesion between aluminum and glass using glue stick amazes me!
I then tried hairspray and ABS juice with the same gcode file (the mendel90 e3Dv6 fan duct with a 10mm brim, 0.3 layer eight and 20% infill). The hairspray provided good adhesion but not enough to prevent warping. ABS juice worked really well, no warping
Bellow you will find some picture so you can see the results. the part printed on hairspray is on the left and the one on ABS juice on the right. Note that I already tried ABS juice before I removed the anodized substrate and it worked quite like the hairspray now that I sanded the plate.