Oh the pain!...

Ok,..

I have spent a little more than a few hours trying to get a good print and I though I had it.....
I know/think this is an adhesion issue but how do I fix it???

As I say, I thought it was going well.... :-/

ABS? If so... heated chamber or SUPER adhesive. Tape isn't going to hold it.
Most recommended IMO is "ABS slurry" or "ABS paste" (abs mixed with solvent)

I have broken prints in the middle and it still curls on the edges with adhesive... there does seem to be some tricks to it/specific combo. of heat/adhesive etc. It didn't work well for me, I went heat everywhere.

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Epop
ABS? If so... heated chamber or SUPER adhesive. Tape isn't going to hold it.
Most recommended IMO is "ABS slurry" or "ABS paste" (abs mixed with solvent)

I have broken prints in the middle and it still curls on the edges with adhesive... there does seem to be some tricks to it/specific combo. of heat/adhesive etc. It didn't work well for me, I went heat everywhere.

Sorry, complete lack of info!
I am printing on a Sunhokey Prusa i3 with a E2d V6 head and no enclosure. Printing in PLA at 200/60 degrees, the print bed is aluminium with painters tape and prit-stick.
I had to slow the print as it was terrible to start with but as soon as this one was looking good I was happy....
1 hour in and it was looking awesome....2 hours, the same....
I went out for a bit, came back to it, the print had completed and still looked good, Only when I pulled it off the bed did I find it wasn't flat....

Just read an interesting article....

[richrap.blogspot.co.uk]

I'm gonna order some 3D Eze.. Maybe that'll help???
Also, does anyone recommend changing my bed to a glass surface? Will I need a special glass???

Scratch that! 3D Eze isn't in the UK.... Or at least, I can't find it????

Edited 1 time(s). Last edit at 08/16/2015 07:13AM by KillerDave.

Any advice would be more than welcome???

For a big piece made out of ABS it is really hard to avoid warping, but with PLA you should be fine, you don't need a hitting chamber or a very complex / expensive solution.

First try to decrease the first layer speed and increase width. Printing at 20mm/s with 150 to 200% layer width (only for the first layer) should make things better.

If you still have warping, then you should probably consider improving your surface. replace your tape with a mixture of water and vinyl glue(the white glue commonly used for wood). Put 1/4th of glue and 3/4th of water, let it dry evenly and you will have amazing bed adhesion.

David.

That's great, thank you!

I have adjusted the speeds and I am printing.... A little more playing with numbers and I think I'll be there????

I have also had a CLOSE look at my print surface.... It's far from flat! If fact, it's dished almost .5mm!!!!
I have ordered a new Glass bed and heat plate....

Thanks again!

Dave.

Sorry,

Info about the 'abs slurry' is about everywhere. Clay 'slurry' is clay and water... ABS 'slurry' is acetone(typically), some use acetone and an "ABS puck" where they will dump some acetone on the bed and rub a puck of ABS around on it.
Some will create some concentration of abs solution(where they just dump some ABS into a containter of acetone until it dissolves).

The theory, like duct tape, is that it sticks better to itself than anything else.

Yep, hard to have a flat print when the printbed is not. I guess that would be #1 - unless you compensate for 'bed flatness' in your slicer and/or add a raft and have enough layers of it to compensate.

I print mostly ABS. my headache remover has been a controlled chamber heated to 60-80c.

I also have my extruder set a little high for what most people print ABS at(also depends on whatever flavor ABS you bought though).

with my current setting I print faster/better with ABS... but gain... I print mostly ABS-
HTH.

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Epop

I print mostly ABS. my headache remover has been a controlled chamber heated to 60-80c.

HTH.

I am actually very curious about how you manage to make a heated chamber that can go up to 80 degrees. Did you find a way to have all your motors and all your electronic out of the chamber? Because I imagine that a stepper motor in 80 degrees air don't have a very long life expectancy

A good way to reduce warping is to ,minimize the area that touch the bed. Print it standing up.

I thought instead of opening another thread I give my 5 cents worth of bed problems here instead.

I am still reluctant to replace my electronics or use external ones just for a heated bed.
So instead I am opting to improve on the surface quality for a cold bed.
After trying various solutions I came to the conclusione that tape for PLA is just bad, no matter how you treat it or what type of tape it is.
Different plastic sheets have been abandoned too as they neither last long enough nor offer the desired flatness.
While being more or less totally drunk after a party I had the weird idea of finding a really flat sheet of glass to replace the crappy one that came with the printer.
Some tests with latex paint and a steel ruler showed the best glass in terms of flatness was coming from the scrap box containing old scanner parts.
Still it had areas with about 0.25mm difference to the surroundings but I tried it anyway.
So that you fully understand my obsession with flatness I have to say that a 0.4mm nozzle is already something really fat for my usage, I rarely use 0.4 and most often it is a 0.25mm nozzle.
The next day, being sober again, I though: what about treating a surface to be printed on like something you would paint on?
Of course I tried already the way of using plastic primer for ABS and it does work quite decent but for PLA it is useless.
I placed a shopping board in the bath tub, let some water run and "sanded" the glass plate using a 300 grid diamond sharpening block.
After about 30 minutes only a few shiny spots were left but they took another 30 minutes as all the surrounding glass needed to be sanded away.
The result is now a milky glass plate with massively improoved adhesion.
If I print PLA on a thin, dried layer of lemon juice it does not matter how ong or big the part is - it just sticks to it.
Only very fine details like spikes are still a bit of a struggle.
Downside for big parts is that sometimes you need to take the print with the plate under running warm water to soften the lemon juice but smaller parts pop off after a tap with the handle of a big screwdriver.

A heated bed always helps, 200% extrusion width for the 1st layer seems necessary, and a thick first layer also, like 0.2mm seemed to help for me.

---

Master Tinkerer

I have been printing PLA on blue tape and a cold bed. I've made some very thin parts the size of a playing card and they were mirror flat after removal. I could place two back to back with no light visible!
-I have a borosilicate glass bed. This is also called Schott glass but is basically Pyrex, so it has no expansion compared to window glass. Since PLA is supposed to have fairly low expansion, it seems like a glass also with low expansion would reduce warping.
-I let it all cool down before I pry it off.
-I have two different brands of blue tape. The standard is 3M #2090 and it was only so-so. I also ended up with 'Pro Tape & Specialities' blue tape and it is darker, shinier and almost TOO much grip! I stopped using it for that reason but went back to it because it is so reliable. I do have to replace the tape after most runs. I bought a thin flexible scraper and sanded an edge on it with a wet-stone (diamond in my case). I lay it flush and tap it underneath to separate, works well.

'Pro Tape & Specialties' was not supposed to be special, just looking for some 2" size and ended up ordering it on Amazon.
Pro tape on Amazon

BTW, with such a great grip I am only doing 135% first layer with 0.2mm layer size. My bed cal is very flat now so I can skim close without worrying about airgaps. 135% also reduces the oversize problem of the first layer.

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dewasa

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Epop

I print mostly ABS. my headache remover has been a controlled chamber heated to 60-80c.

HTH.

I am actually very curious about how you manage to make a heated chamber that can go up to 80 degrees. Did you find a way to have all your motors and all your electronic out of the chamber? Because I imagine that a stepper motor in 80 degrees air don't have a very long life expectancy

Nope, as my machine was setup and designed to fail. before the first year was up two extruders died and number three went a month or so back. I put a foam pad between the electronics and the chamber and ran it for a few weeks like that. I plan to put some insulation and maybe water cooling around the steppers but haven't done it yet. going through a re-design for extruder setup atm.

I've started using a solution on my glass-topped heatbed suggested by dc42 elsewhere in the forum - sugar water.

Take a small glass of hot water and dissolve a few teaspoons of ordinary sugar - keep going until the solution is saturated and you can't dissolve any more. Wipe this onto the warm bed (not hot!) with a cloth - it'll dry to a matt smeary coating.

I print PLA and ABS onto this, and very rarely does anything come unstuck, but the pieces come off quite easily when the bed cools (sometimes you get an unexpected click as the piece comes free). This is on a Prusa i3 without an enclosure. Each coating lasts quite a while.

It's worth a try anyway - it's cheap, and easy to wash off if it doesn't work for you.

Edited 1 time(s). Last edit at 09/13/2015 04:22AM by David J.

I want an alternate to PVA, which is messy and difficult to scrape off. Water works but not very easy. Nylons and T-Glase PETT both recommend PVA.

Ok, I've been real busy but here is where I am now....

I have now fitted my printer with and new RED heat bed with a Borosilicate print surface and have tried 3dEez and BuildTak... both gave a much better result but now I fear my problems lay elsewhere!!!

Do I need to reset my print gap after every print??? What a chore!

Printing with PLA onto a BuildTak sheet at 200 - 210 gives me a much better result with great adhesion... I am much happier now but we shall see how it goes as the weather gets cooler from here on and so will my shop!....

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KillerDave
Do I need to reset my print gap after every print??? What a chore!

No, use a Z probe to establish the Z=0 height at the start of each print using the G30 command. For best results, heat the bed and hot end to operating temperature first.

If you don't already have a Z probe, there are several sorts to choose from. One type that works well with glass beds is my own mini differential IR sensor. More details at [miscsolutions.wordpress.com].

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Sorry for the late reply and thank you for your suggestions....

I have been printing with some great results!.. still not perfect but very good for such a cheep printer!

I will be fitting a height sensor of some sort and yours does look very good!...