Abs won't stick to bed

I am getting very frustrated with a problem I hope someone can help with.

My printer is working perfectly apart from one small problem. The abs wont stick to my glass bed.

I have a heated bed at 110 and a hot end at 230.

The new hobbed bolt I made works great and there is abs extruding very well but it just won't stick.

I have tried glass cleaner, acetone, masking tape, upping the bed temp to 150 and the hotend to 280.

I have included a pic of my hotend but as I said the abs is melting and extruding.

The only thing I can think of is that the abs is cooling too rapidly but there is less than 10mm from the olloy block to the end of the tip and i can't go any lower.

Might have to order a j-head as others have had great success with these but the one I have seems to be working to a point.

You need to use either kapton or blue painters tape if you want it to stick....kapton is the best that I've used and it has to be cleaned with acetone or you'll get curling.

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[johnbiehler.com]

The 10mm can be an issue too.

I used a 3M double-sided tape on a non-heated aluminium plate and it still wouldn't
stick and my clearance is only 5mm. You have to be closer.

Once it deposited enough plastic that the tip got kind of close to the part, it started sticking again.

I couldn't get it lower either. What I want to do with mine is get a sheet of glass and make my own
temperature controller. Then I'll preheat the glass bed to whatever I want and it should work...

The advice with tape is good too. I remember seeing a video (either straight from YouTube or linked
from reprap.org) where they explain which tapes work better.

Here is a link explaining ABS: [reprap.org]

Heated PET (polyester) tape on glass is much better than kapton. The problem with kapton tape is that it's a lot thinner than PET tape. If you print large pieces on kapton, it pulls the kapton off the bed and you get bubbles. PET does better since it's thicker. And once cooled, parts come right off.

The hot end that you're using is the older style with the nozzle threaded into the PTFE insulation. This is well know to fail eventually as PTFE softens when hot and eventually gives.

To adjust the clearance between the nozzle and the bed when z is in the home position, you can use paper as a feeler gauge. Heat up the nozzle and wait about 5 minutes to allow for thermal expansion. Then put a sheet of paper on the bed and home the z. The clearance is right when you can move the paper with only a slight resistance.

Thanks guys,

I have adjusted my hotend down to about 3 mm clearance between my alloy block and my tip.

I have ordered some kafton tape and will buy some blue painters tape today. The type at Bunnings in Australia is called edgelock but is still 3m blue painters tape so I hope this is the same. Will cloth tape work as well?

I am using a tdc347 thermistor on my hotbed but I don't think the hotbed temp is that critical as others have printed onto unheated glass with abs.

I was not really happy with the connection in my hotend either and might have to try and build a support arm connecting the tip with my bolts that hold the extruder onto the x carriage. This will take the weight off my hotend.

Just found out that My clearance is at least 6 folds of paper so I will have to adjust my bed up to just one thickness of paper.
This may be my main problem. I thought it looked closer than that.

I do not acquire much knowledge about that , I hope someone have solved your problem.

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[www.mulberrybagsoutletshop.co.uk]

Had my first successful print last night of herringbone small gear.

The problem was solved by using blue painters tape on my glass.

I still need calibration but it works.

Maybe someone can help with settings for sprinter. I am ble to change the settings now but need the numbers.

I am using 2.5 gears on x and y ( I think, they came with the steppers ) with t5 belts, and gregs accessable extruder with heringbone gears.

Thanks all.

Greg