Some people say work smart, not hard. But, I am incredibly lazy, so I don’t want to work at all.

That said;

The 3D printing community is working way to hard on designing complex parts. They are really good parts, but they take work to produce.  I want to help you guys out with a bit of insight from organic chemistry,  so designers can put their skills to really good use streamlining their parts.

4 of Concepts with Chemistry to Help the 3D printing community
Warning: (generally) Do not mix ketones + alcohols = Boom

1st Concept: No hot bed necessary
ABS cement can be used as a replacement for a heated build plate.
Just smear it on a a flat surface, until it streaks, less is more.
If you can’t see through it, it is excessively thick (harder to remove).

2nd Concept: Make your own ABS Cement
Any color of ABS plastic can be solvated (dissolved) in:
-acetone (faster)
-Methyl Ethyl Ketone (MEK)- 2-Butanone (slower)

This means you can recycle your scraps by dissolving them, and make custom colored ABS Cement.
By changing the ratio of ABS to solvent, you can adjust the viscosity of ABS cement.

3rd Concept: Design parts to be bonded together
Many of the parts designed by the 3D printing community bolt together. The initial designs key up well, but the obsession with the hex nut recess is unnecessary.

-ABS cement to bond parts together chemically, and get a structural part with no bolts.
-ABS parts built sparse can be filled with ABS cement, and then drilled out, sized up, tapped, or repaired.

4th Concept: Surface finish
A mild coating of acetone or Methyl Ethyl Ketone (MEK) can bring printed printed parts to a high gloss finish, and can reduce/eliminate print layer ridges.

The Technical Stuff

ABS plastic consists of three major components (Acrylonitrile Butadiene Styrene).  Solvents that have a similar organic structure can help break down, the components of the plastic.

http://en.wikipedia.org/wiki/Acrylonitrile_butadiene_styrene

This is solvated easily by Methyl Ethyl Ketone (MEK) Industrial Name
2-Butanone IUPAC Name

These chemical names are one and the same, but Industry and science have different naming conventions. It is just like the inches vs millimeters problem.  Regardless, 2-Butanone = MEK and is a cousin of the Butadiene linkage that holds the ABS polymer together. Acetone acts as a polar protic solvent that can generally solvate a wide variety of polymers. Both of these solvents can make a dilute ABS solution that can use the intermolecular forces to bond the plastic polymer to the glass. Intermolecular forces are what geckos use to run on glass, teflon, or any surface. Bonding with enough surface area on a molecular level allows the two objects to acts as one. This is how the solvated ABS prevents delamination without a hotbed, but by the same mechanism of intermolecular bonding.

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12 Comments on ABS plastic & Solvents: 4 good ideas

  1. No need for a hot-bed for ABS prints sounds great. I have to try this out. Thanks for posting it.

  2. Unfortunately it did not work for me on glass:

    https://lh5.googleusercontent.com/-idvL5FaDVNk/T-A2DcizWdI/AAAAAAAAMxI/3uwePwsvM3U/w543-h407-k/IMG_20120619_101307.jpg

    The contraction forces will lift the edges of my prints.

    Slurry was made of acetone and ABS from failed prints.

  3. ganter says:

    Thanks for sharing. I checked and our team is using a glass with texture. As the neoceram ( fireplace glass) has major adhesion to ABS.

  4. Joseph Scott says:

    I’ve been using ABS/Acetone mixture on glass salvaged from retail fixtures. It works pretty well.

  5. ganter says:

    Glad you are having good luck. Recently we had a print that stuck so well, we pulled off pieces of the glass plate!

  6. Sydney Holistics Centre says:

    Solvent-welding plastic involves using a solvent to partially liquefy plastic along the joint and allowing the joint to solidify causing a permanent chemical weld.

  7. bowman says:

    Fusing to ABS parts together by solvating them causes bonding, but styrenes tend to degrade easily, the more solvation in the joint the less structural the joint is. Smearing ABS cement on the hot bed is not the same as solvent welding because the the solvated acetone is bonding to glass, aluminum or so other non reactive surface. Then after the ABS cement has dried, 3D printed parts can fused to the initial layer of ABS thermally.

  8. Jagankumaar says:

    In FDM process ABS M30 sticks with acrylic sheet , is it possible to seperate both even if
    bonded Thermally.

  9. ganter says:

    Don’t really know. If you can find a solvent for acrylic which leaves ABS undamaged then yes. Why are you printing directly on acrylic.

  10. bowman says:

    The ABS will dissolve slightly faster then the acrylic which I imagine is the opposite of what you want

    Acrylic (acrylate) and ABS (Acrylonitrile Butadiene Styrene) are chemical cousins and because the both share the acrylonitrile monomer it makes it very unlikely to solvate one plastic without the other. We have run into this problem before, and the bond between ABS and acrylic is so strong that is should be used as a feature in 3D printing. ANything that could dissolve the acrylic will dissolve the ABS faster because of ABS styrene groups are easy to solvate.

  11. gremlin says:

    Hi, i’m not so good in chem’ : if i dissolve ABS filament into acetone, then let the acetone evaporate, will i get ABS too ? will it be structurally equivalent (seems to get a little rubbery, but will i get the 40 MPa tensile strength) ? Cheers

  12. ganter says:

    should be the same once ALL of the acetone is evaporated.

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