Tuesday, July 20, 2010
The main advantages are: high resolution, very small waste and no powder mess... and most important low cost for building :) ... but high cost for the resin :(
But there are also some disadvantages: if you want a high resolution the
printing area must be small, because of high price of chemicals you will spend
a lot of money for big printing area.
I am not buying a DLP kit to build the machine as this would cost a fortune, so I am using a DLP projector that you can find anywhere.
See the first draft design:
Some of my findings so far:
1) The projector must use DLP chip www.dlp.com
2) If the projector lamp is UHP over 200W you will get very fast curing
(excellent). Don't use LED projectors, you will need 4 to 5 minutes for each
layer, maybe 100 years for building something, and you will not get a good
3) Resolution: I am using a 1024 X 768 (0.55'' DLP chip) – I bought a used
projector on e-bay for less than 500USD. If you want a higher resolution you
will need a more expensive projector (over 1000 dollars). As I am planning to
have 100X80X130 mm building size which will give me a very good resolution, one
pixel will be thinner than a human hair (100 microns). My projector is Optoma
EP728. Projector lamp is cheap, I bought spare one...
4) The Z resolution is also important, I am using a microscope screw lead (140mm
- travel). This will give me a resolution around 0.01 mm on Z
5) As the projector lens are not for short throw distance, I did a small
modification to adjust the focus in short throw. (Removed some screws – my throw
6) The top-down building process has 2 main issues: bubbles and chemical level
as you introduce more solid material (elevator) the level goes up which could
give a small difference on Z axis. For this reason I am building a bottom-up
platform, this makes the project simple and also reduces the cost of chemicals
as you don't need to have a full Z deep building area. Similar to this
commercial one: (http://www.envisiontec.com/index.php?id=60)
7) Software: For slicing the solid I will use any commercial (Magics) or non
commercial (Fogassa/Pov-ray). For printing I am building one which I can share
later on. Mainly I control the stepmotors using parallel port and projector
using the second monitor output from my video board.
8) Chemicals: I have purchased one material from Dymax for keypad coating (very
hard (D80) and low viscosity that will arrive in 4 weeks, if it works it will be
best cost (around 200 USD per kg – must be cheaper in USA).
10) If this chemical doesn't works, I have to use e following recipe: (I have
the rationals for it if you need)
# 1,6-Hexanediol diacrylate (Aldrich 246816)
# Sudan I (Aldrich 103624)
# Phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (Aldrich 511447)
While waiting for a solution for the bottom stickiness I spent sometime "beautifying" the printer, actually most of the things I have done are was mainly to avoid external light source that could cure the resin and improve the printer.
Really looks nice now...
Most of the things are made from acrylic sheet. The transparent red acrylic protects the building area from external light.. pretty cool...
Thursday, October 14, 2010
- Homemade High Resolution 3D Printer - DIY
- 3D printing with visible light - Hack a Day
- Homemade High Resolution 3D Printer - DIY: Last post for today... initial plans and findings
- Homemade High Resolution 3D Printer - DIY: Good looking Printer...
- Homemade High Resolution 3D Printer - DIY: Final results.....