Wild OpenPCR

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OpenPCR in the wild

Attempt to build an OpenPCR just from the desctription on the website OpenPCR without a kit or any supplied parts.

Laser Cut Housing

First and easy thing is to go up to a FabLab and laser cut the wood parts for the housing. Need to get the files from the website and have the most recent version of SolidWorks to extract the drawings...

Here we go;

Pcr laserhousing.jpg

And the one pdf with all the parts as of November 2012:
File:Pcr laserfiles.pdf
Got some additional information from Josh from OpenPCR: The downloadable files are the more recent versions of our design.

And:

The OpenPCR BOM can be found here:
https://docs.google.com/a/snowrise.com/spreadsheet/ccc?key=0AiaWH3PL_9CndG1GbmtSZ1I3aGdkQkE4YVhwZ3o5c1E#gid=0
Good to know.
What else do we need?
- The PC-Cooler with 90° heat pipe is easy to get for around 20 euro.
- The nice and small power supply that fits into the housing is not so easy. It is a "Flex 1u PC Power Supply 200 W ATX. Bigger (standard size is more easy and should do, just won't fit into the housing
- Arduino ok, SMD driver board with AD converter, connectors, feasible. Will try to simplify the layout to make it single-side DIY. What are the big resistors for? Some kind of heating? Have to figure out.
- LCD Display - standard, anything goes, 4 Lines are nice.

Heat Block and Peltier Element

Now one tricky part is the heatblock and the peltier element. For those we have two nice hacks: 1. A peltier element with the exact right dimensions and with some luck even the rough thermo-block can be found in one of those little electric fridges:

Pcr fridges.jpg

Found those in electronic waste.

Pcr extraction.jpg

Unscrew the blower and the cooler and you will find the peltier element.

Pcr heat parts.jpg

All you need, a aluminium heat-block (think the original OpenPCR heat-block is cooper and then chromed, right?), peltier element...

Now that we have the heating/cooling element and the block we need to get the right holes for the eppendorf tubes in it.
Josh says from his experience: "Different manufacturers make 200 ul tubes of different dimensions. But we designed OpenPCR around the key angle of 17.5 degree cone angle, which seems to work for most PCR tubes. Good luck in your endeavors".
So with a fried we designed a special milling tool around this angle. We make this an "Open Shared Hardware Tool", so who ever needs to make some nice 17.5 degree holes may borrow these for a while :-)
This is the drawing with dimensions:

Pcr eppendorf milling tool.png

File:Pcr eppendorf milling tool 02.pdf
File:Pcr eppendorf milling tool 15.pdf

And the ready made tools:

Pcr eppendorf milling tools.jpg
Pcr eppendorf milling tools close.jpg

Here different thermo-blocks made with the tools:

Pcr blocks.jpg


This is the PC blower I found (90°, with heat pipe), seems to fit pretty well:

Prc PCblower.jpg


The Electronics

The Electronics:
While the mechanical concept and construction is pretty well done

Programming the Arduino