Introduction: Laser Cut Soldering Air Purifier

I have always wanted to have a small air purifier around when I am soldering electronics.

When I found a guide from Make magazine that showed how to make a portable fume extractor I knew that I wanted to build it for myself!

However I did not like the tin case. I do however have access to a lasercutter. And therefore I wanted to make an acrylic case using the cutter. I found the closing mechanism and hinges from Adafruits Raspberry Pi case appealing and therefore I have used those to secure the front. Links to both the guide from Make and Adafruits Pi case can be found below.

I have later made a workshop where we build this and wanted a guide to use in the workshop. This instructable is made for use in that workshop.


This instructable is VERY MUCH a work in progress, as I will try to update it every time I work on a workshop. So if you find any errors or have any idears for improvements let me know.

Make Magazine guide: http://makezine.com/projects/mini-fume-extractor/

Adafruit Pi case: https://www.adafruit.com/product/1326

Step 1: Tools and Materials

For this project you will need:

Materials:
1x 4 x 4 cm fan: http://www.aliexpress.com/item/20pcs-LYF-40mm-x-40...

2x metal grills: http://www.aliexpress.com/item/40mm-Computer-PC-Ca...

1x barrel plug: http://www.aliexpress.com/item/10Pcs-3A-12v-for-DC...

2x 9v battery clip: http://www.aliexpress.com/item/10pcs-New-9v-Batter...

1x Variable step down: http://www.aliexpress.com/item/Mini-360-DC-DC-Buc...

1x slide switch: http://www.aliexpress.com/item/Details-about-New-2...

Some carbon filter (we will cut this into smaller pieces later): http://www.aliexpress.com/item/10-pcs-Activated-Ca...

1x 3mm cast acrylic sheet (minimum 16 x 21 cm)

4x 3mm x 10 mm bolt (I used 16 mm instead but 10 would be better)

4x 3mm x 16 mm bolt (I used 230 here but 10 would be better)

8x 3mm nut

Wire in different colors

Shrinking tube or insolating tape

Hot glue or acrylic glue

Nail polish

Tools:

Screwdriver

Stanley Knife

Access to a lasercutter

Soldering Iron

Hot glue gun

Step 2: Lasercutting the Parts

Cut the acrylic sheet into the pieces for the case using a laser cutter

I have included an illustrator file containing the template for the case.

Because this has been changed so many times there are some problems with the case, like small gaps and skewnesses. Hopefully I will find the time, sometimes in the near future, to correct this. In the meantime if you do any corrections please consider sending me the changed template.

Step 3: Add the Barrel Plug and Slide Switch

Add the barrel plug and the slide switch into the different holes. Use pliers if necessary.

Remember to solder the wires onto the switch so it fits with the on off markings in the acrylic. The correct position of the wires can be seen in the pictures.

After this solder wires onto the slider and the switch as shown in the pictures. I have used only black wire for the switch as this will later be used to complete the ground connection.

Step 4: Assembly and Gluing the Parts Together

Assemble the parts as shown in the pictures. Starting from the back, adding the bottom, then the partitioning walls on the inside and, as the last piece, the top with the slider.

It might be a good idea to run the wires for the battery clips through the small holes in the inside walls before you glue the parts together. It makes the whole assembly a lot easier


Glue the parts together from the inside using either a special glue made for acrylic or hot glue. The choice of glue depends on the transparency of your acrylic. If the acrylic is transparent the hot glue will be very obvious.


As my version is made from non transparent acrylic I ended up just using hot glue. This also alows the case to dry faster.

If you use hot glue a tool for smearing out the glue comes in handy. I used the bottom part of a table spoon for this. Be aware that there is not much space for the glue, so try and make the lines of glues as thin as possible.

Step 5: Assemble the Battery Clips

Put the battery clips in series by connecting the black wire from one of the clips with the red wire from the other. Tangle the wires around each other and complete the connection by covering the exposed area of both wires with solder.

Remember to cover the exposed part of the connection with shrinking tube or insulation tape.

Step 6: Connect the Battery Clips and the Barrel Plug and the Step Down Converter

Strip the remaining wires from the battery clips and the barrel plug.

Connect the wires from the barrel plug and the batteri clips in parallel to the step down converter. Remember to connect the black wires to minus and the red wires to plus.

Step 7: Set the Drop Down Converter


Please be very carefull and read the whole step before you continue. I have seen a lot of people breaking the step down because they get impatient and turns the screw to much.

As we have used a variable drop down converter we need to set the output to be stable at 12 v. If you want more suction you might consider setting the dropdown to above 12 v. However this will use more power so the batteries will die faster. Also it might not be good for the fan, so do this at your own risk :)

Start by connecting the battery clips to two 9v batteries. Put your probes from your multimeter on the output from the drop down. Use a screwdriver to turn the screw on the potentiometer on the drop down converter. BE VERY CAREFULL WHEN YOU DO THIS. IT MAY TAKE SOME TIME FROM YOU TURN THE SCREW TO THE VALKUE ON THE DISPLAY CHANGES.

Turn the screw until the display from the multimeter shows that the drop down delivers around 12v.

A helping hand from a friend is handy here.

Secure the screw with hot glue or nail polish.

I normally prefer nail polish as this makes your able to move the screw later again if you want to. But I did not have any nail polish around so i used hot glue instead.

Step 8: Connect Fan and Drop Down

Connect the red wire from the fan to the plus side of the output from the drop down converter. Solder the wire.

Connect one wire from the switch to the minus side of the drop down. Connect the other wire from the switch with the black wire from the fan.

Cover the whole drop down with shrinking tube.

Put the drop down and fan into the case as shown in the picture.

Step 9: Cut the Carbon Filter

Cut the carbon filter into squares that measure 40 x 40 mm

Step 10: Asssemble With Bolts

Put the nuts into the holes in the fan. Hold the fan grill in front of the case and put the long bolts through the grill and front into the nuts. Screw the bolts in completely using a screwdriver.

Secure the other grill to the back plate using the 4 short bolts and the remaining nuts

Step 11: Enjoy

Install the carbon filter by placing one square in the middle of the fan as shown in the picture

Enjoy tour finished soldering fan.

If you build this, or gets inspired by this to do another build, please consider to send me the pictures :)