Electric Coffee Grinder

Its been a long time since I wanted an electric coffee grinder. it had to be a burr grinder and

baying one was too expensive.

I had an old battery operated screw driver that the batteries where long gone and an old hand

driven coffee grinder. it was a match made in haven :)

Step 1: Buying the Right Transformer

The screw driver was a skil 3.6V. after taking it apart (I charged the battery first) i connected it to

a multimeter and got 4V. than connected the everything through the multimeter to get the Amp

needed. ( to find that, you have to manually stop the engine and see the max amp in the loop) I

got 4 Amp.

the closest thing I found was a led lighting transformer that was 5V 5Amps on ebay.

http://www.ebay.com/itm/DC-5V-5A-25W-Voltage-Trans...

Step 2: Connecting a Bit to the Manual Grinder Shaft

The coffee grinder has a main shaft, and at its end a rectangular shape. I used a bit and bended

two nails to fit the both together. I tried using a plumber rock glue (it probably has a different

name) but without success. the nails work perfectly.

Step 3: Building the Base

I started to work with balsa wood and that did not work out at all.

so took an old wire wheel and

used it's plywood.

Not too much to say about this step­ I am sure most of you already know what to do ;)

Step 4: Power Connections

See diagram above.

I used an old computer power unit that didn't work and took its switch. I wanted a 220V switch

for safety reasons. using a switch after the transformer meant that I have live power all the time

in my grinder.

Step 5: Making Coffee

Probably a different instructaible...

I would love to hear what you think and answer any questions you may have.

Comments

[HenriZA]

Very cool. I like it. Want to make something similar for a fully automatic coffee machine. Got some tips from your project.

[mechanofreak]

Cool design! Electric burr grinders start at $100(for OK quality ones) and just go up. The decent ones I'd like to buy cost ~ $200.00. This is a great alternative. So which brand manual burr grinder did you use for this? And do you find the grind consistent?

[IdoM1]

The grinder I had was an old one looks like something you can buy in a tourist shop in Sweden :)
I'm sure you can get a better one very easily.
but still, its consistent enough for my coffee machine.
my main problem is that you can't change the grinding size very easily but once you get the right size for your machine you forget about it.