Last post for today... initial plans and findings

My plan is to build a chemical 3d printer similar method of this one (http://www.youtube.com/watch?v=HbNl0CsB2xE). Using visible light and DLP chip to cure visible light resin.

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.

Some of my findings so far:

1) The projector must use DLP chip www.dlp.com

2) 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...

3) 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

4) 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
distance 170mm)

5) 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.

6) Software: For slicing the solid I will use any commercial or non
commercial (Fogassa/Pov-ray). For printing I am building one which I can share
later on.

7) 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).


Cheers,

Junior

What do I need to think while planning to build a 3D printer?

Well there are many things you need to consider.

1) What is the purpose?
This will help you to decide which kind of material, build size, resolution, etc. The most important thing is that your choice will also define the costs :(

2) What skills I need?
Well, today you can learn basically everything on internet, you won't become an electronic engineer overnight but I am sure you can learn how to control a step motor (I did it :)). You can ask help to friends.

3) What about tools?

You will need many precision tools, it is not possible to build such machine with simple tools. You may need to use a CNC for precison parts. I will mention some tools used while building the printer.



4) Time and money..
Yes, you may spend sometime to do it and money too. I expect to spend around 1.5k to 2k USD to build one. But I already spent 2 times this amount just in tools last 2 years, but don't worry you can use your friends tools also.

Have fun

Jr

Introduction and background...

Well, I will start this blog with short introduction: My name is Junior (actually is not but as I have the same name as my father I kind of adopted this name because it was easy to differentiate when my mom was screaming at me or my father).

When I was very young (maybe 5 years old) I started opening everything with a screwdriver... after X'mas when kids were playing with their toys, I was opening my toys to understand how they work...

Most of the times I was able to assemble it back... but always was not able to find a place for all screws... :)

At age of 12 I built my own gasoline motorized bicycle...

Ok, let’s keep this short.

I start thinking on 3d Printing many years ago when I saw a video of the first SLAs, quite nice, but too expensive for me. So I have been working in some ideas. For few months last year I worked in a Powder printer, using a HP DeskJet and powder. I did manage to control the printer and create a flatbed printer but the powder is an issue, where I live the humidity is over 80% in average and powder become stone overnight.

So I gave up… I was planning to build something with plastic similar to Makerbot http://makerbot.com/ but I was looking for some ideas to improve the resolution… and I think I found the right solution that I expect to share here.

Ok, few things before we start:

- The ideas here were not tested by me before, so if you going to try it will be by your own risk. I do not guarantee the results.
- As I am quite busy in my work I do not guarantee when I will be able to post new things.


Cheers,

Jr