PLA + Glass + Hairspray = Win

I have given up on ABS, and I have not looked back.  With the combination in the title I get 100% success rate, no warping or peeling off from the print bed.

I ordered a piece of tempered glass cut to the size of my heated bed from a local vendor right from the beginning.  I like the glass because of the smooth finish on the bottom, and because my bed is very level and even.

The moment I switched to hairspray and PLA everything changed.  At first, I didn't like PLA.  It turned out that was the fault of my extruder not working properly and my slic3r settings not being dialed in correctly, especially in terms of my nozzle diameter.

I purchased a can of Pantene Pro V and of course went with Maximum hold.  They have a 4 circle rating on their cans and Maximum Hold had all 4 circles filled in.  Alright I said, "This can of hairspray is manly enough for my purposes."  And wow did it work.  PLA sticks to hairspray on glass like glue with only a fine layer of spray.  At first I was cleaning it off and re-applying between prints, but I found that I didn't need to do this.  I have been printing multiple parts in the same place without re-applying hairspray and the pieces are still sticking.

Once the glass has cooled enough that the PLA is no longer flexible I tap the pieces off the glass with a small dead blow hammer.  Don't hit the pieces too hard, for the sake of your printer.  I tap lightly against the piece until I hear cracking sounds, assuming they don't go flying on the first tap (tends to happen with small prints).  For larger prints that are sticking really well, I work my way around the piecing tapping from each side until I heard cracking.  The cracking sounds comes from the piece breaking free of the hairspray.

Note: If you are having a really hard time getting a piece off the glass, probably because it has a large surface area, you can put the glass plate with part in the freezer.  Don't do this is the glass is hot because it may crack or shatter.  After a short while in the freezer the part will either pop off on it's own or be much easier to tap off the plate.

My setup

3/16" thick Tempered GlassSainSmart Heatbed MK2a
Pantene Pro V (Maximum Hold)
70C - start to finish

update: I have recently been lowering the temp to 60C and have still been fine.

Periodic Cleanup

Needed: Isopropyl (rubbing) alcohol, shop towels and razor blade.

If too much hairspray has built up I will pour some alcohol on the glass and scrape the bulk of the hairspray off.  I then come back with shop towels and alcohol to get it all clean.  Hairspray build-up over time didn't affect my prints, it just got messy.

Examples prints on old hairspray.  I started the print without thinking about re-applying and got nervous half way through when I saw the print bed shaking and how much angle the legs had verses how small the contact surface area was.  The print come out fine and stayed locked to the glass until it cooled.  I still had to give it a light tap to free the piece.

Nozzle Diameter Affects Print Quality

I built my printer and so I did not have the benefit of a factory calibration, however I have learned a great deal about printer settings and the various outcomes.  At first the nozzle diameter setting in Slic3r seemed to be plug and play.  The nozzle I purchased says it's a .40 so that is what I put into Slic3r.  Consequently my prints were coming out awful because over time the nozzle was getting farther and farther away from the item.  The distance is incredibly small but matter greatly.

The issue is that what Slic3r thinks it is extruding out of your nozzle does not equal reality.  Depending on the actual size of your nozzle and the setting you put in, it might be putting out a lot less or a lot more than it thinks it is.  With my first nozzle labeled as a .40, which is what I put into slic3r was closer to 0.38.  This is a such a small discrepancy but it matter because my exterior layers were showing gaps and not properly laying on top of each other.  In this case Slic3r thinks it is putting out .40 worth of material and compensating appropriately on the Z-axis for each layer.

My next nozzle was just the opposite, and I was getting squashed wide extrusion lines.  My layers no longer had gaps but my prints were shorter and wider than they should have been.

The fastest way to calibrate this is to do a small area but tall print and make small adjustments to the nozzle diameter.  Keep in mind that this setting goes hand in hand with the filament diameter.  Hopefully you have digital calipers (I bought mine from Amazon) to verify the width of your filament, and would also be useful in verifying the dimensions of your printed object.

In your settings...
Nozzle diameter to large, will result in gaps between layers.
Nozzle diameter to small, will result in smashed wide strands.

Both issues will get worse as your print height goes up.

The Bad

Examples of when my nozzle was set to large than it actually was.  Gaps occurred because the filament did not land right on top of the previous layer.

The Good

Once you get the nozzle amount dialed in the lines come out very clean.  I believe I printed this at 200 microns.

Bad extruder design

If you get started in 3D printing, you need to know right up front that the heart and soul of your printer is your extruder.  Yes, there are many other critical parts but in the end you won't create a single item unless you can extrude plastic and extrude it well if you want decent looking creations.

I went with a dual extruder which is really just two single extruders mounted side by side, there isn't anything special that makes this a dual extruder.  The kit was produced by QU-BD as the MBE v9 and is an open source design.  Being an open source design is great but as of this writing QU-BD has not bothered to adopt any of the great ideas that have poured out of the community on their currently flawed design.  If you search for this extruder you will find the digital tears of 3D printers everywhere.

Flaw 1

Filament tube - this all metal tube has caused many problems for people trying to print with PLA.  PLA generally has a lower melting point and heat was traveling up from the hot end enough that filament would melt just enough to become sticky, then cooler filament starts piling up on top of it and a train wreck ensues.

Flaw 2

Set screw - the design relies on a set screw squishing filament against a drive gear.  The gear has a curved slot in it.  This is the largest cause of failures for prints.  You want your extruder to put all it's force into pushing the filament down to the hot-end.  This set screw causes immense friction and you are losing downward force.  The set screw also tends to back out over time and all of this relies on the filament being a constant, which it is not.

Filament tends to very in width ever so slight and a set screw does not compensate for this.  The pressure of the set screw is also relying on a constant state of the filament which changes due to temperature and humidity.  Guess what QU-BD, we are printing over a heated bed and a hot metal extruder.

Outcome

If you are starting out, don't buy this extruder.  If you already have one, we can fix it.  If you want to save some money, have patience and a friend with a working printing, you can buy one of these MBEs and fix it.  On to the fix...

The Fix

You need a new filament tube and a spring tension-er.

Part 1

I bought a 30mm tube from Mike on Ebay.  He uses a metal lathe to hollow out a button head metric bolt and then inserts a PTFE liner.  Melted filament will not stick to the PTFE which remedies flaw 1.  He has two sizes, the 30mm bolt allows you to get a wrench in to tighten the nuts against the cold-end.  I added a couple of nylon bushing to offset the extra height thereby negating any lost print height.  

Part 2

I created my own tension arm based on the original design by Barton Dring.  My design uses the spring block from his page.  I printed and tried a number of different designs and while Barton's design is a good one, I wanted to use 608 bearing which I had aplenty.  I found these to be cheaper since they seem to be more common.  There are other 608 bearing designs but many of the warped over time from the heat of printing.  So, I created an arm that is much stronger and you can print using PLA.  Although it would be better, if you can manage it, to get this printed in ABS.  ABS withstand heat better than PLA.

You can also upgrade the filament drive gear, however you use the original raptor gear that comes with the extruder.  I have been using the raptor with these improvements and my prints look great.

Samples

Both of these arms are printed using PLA.  The blue one came first and is currently in use on my printer.  One thing I have learned is that when your printing is working well, print your critical pieces first.  The blue arm is still working great after many hours but I wanted a backup just in case.  I red arm was printed at 200 microns while the blue one was printed at 400 microns.  I also increased the fill density to 80% on the red arm verses 50% on the blue one.

3D Printing

I have jumped into 3D printer and I am really excited.  So far it has been incredible highs and lows.  I knew I wanted to do this but I also knew I didn't want to spend a huge amount of money.  Especially since my hobbies ebb and flow.

For about two weeks I wandered around the internet comparing 3D printers.  There are so many, with varying prices and features and I had absolutely no idea what I was getting into.

I landed on this printer, the ORD Hadron.  It looked like a really interesting and I will admin stylish design.  The design is also open source so it can be improved upon without a royalty.

The ORD Hadron is just a frame and did not come with any electronics or extruder.

I then purchased this electronics package which includes the driver boards and stepper motors.

For the extruder I purchase QU-BD MBE v9, link intentionally not included.  My advice is do not buy this extruder, it will cause you nothing but heart ache and pain.  If you already purchased this extruder I will go into how to fix it in another post.

Pictures of my printer and all it's parts

An updated picture with the new tension arm and nameplate.