Miserly Muffin Fan




10 to 20 years ago Rotron made Muffin Fans for super hot computers and electronic gear. These fans are very powerful and quiet. They are rated over 100 CFM's. Finding them in old equipment is the cheapest way to find them. They normally sell for $6 to $15 for a used one, a new one from Digi-Key is $40!!!!. I would never pay that much.

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Step 1: What to Look For

Muffin by Rotron is the best. Newer ones are made in Mexico, older ones in the USA. Make sure it says 110 volts, not 220 volts, unless you have 220v. This one only consumes 14 watts!! There are quieter, less powerful ones that use only 7 watts. 10 to 20 year old ones will normally work fine.

Step 2: Attach Cord

Any size cord with plug will do, this one is just 14 watts, not much of a load. This cord came from a thrown away electric toothbrush charger. The cord is tied tied the mounting holes and soldered to the contacts. The exposed connection was insulated by a dab of abs glue.

Step 3: Feet

I place dabs of silicon on all the corners, it reduces vibration transmission to the tabletop. The feet keeps it from creeping along. I have attached plastic wood clamps to mount the fans
The fan is powerful enough to blow across a bedroom.
It will dry your wet boots and socks.
It will keep you cool cheaper than a ceiling fan (100 Watts)
14 watts is a lot cheaper than 500 watts for keeping cool.
The other brands from China/Germany use .1 amps
The size is just 12mm square and 4mm deep. The mounting hole are 4" apart

Step 4: They Last Forever

This one has been operating for 6 years. I will need to clean it.
It has a spring clamp to hold it in place

Step 5: More Facts

Be careful the fan speed is fast it will nick you finger. Grill guards are available.
If the fan falls on its face with no air to circulate, it can break its blades or burn itself out.
I also have one in my bath running 24/7 to reduce moisture and to reduce circulation of the Old Lady's Baby Powder.

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    10 Discussions


    Reply 9 years ago on Introduction

    Anyplace with old or surplus equipment, just google fans or surplus electronics.


    Reply 7 years ago on Introduction

    old post, sorry.
    i realized the other day that my dad has not one, but 2 of these things in his garage!
    he has it hanging above his heater to blow warm air around the garage.


    9 years ago on Introduction

     I actually use one similar to this as the exhaust fan for my kitty litter box.  


    10 years ago on Introduction

    I just realized, iIhave two of these just laying around! I never really took the time to try them out!

    Rob K

    10 years ago on Introduction

    Delta makes a fan that looks like that with the 3 blades but they are way to loud. 141.96 CFM @ 3700 RPM 52.5 dBA and they have a 12 blade one. 220.01 CFM @ 4600 RPM 65.0 dBA What you have there might be around 40 dba

    1 reply
    gcrdcnRob K

    Reply 10 years ago on Introduction

    For a Muffin XL MX2B1 its 47.6 dBA 15 watts .18 amps. 100+ CFM No other mfg. come close, but for $40+ list price is too much!!


    10 years ago on Introduction

    how big are these roughly? and what sort of things can we find them in? do you know if they can be found world wide or just in the states?

    2 replies

    Reply 10 years ago on Introduction

    4 mm deep 12mm square. They should be inside old 20+ old electronic equipment. Old mainframes, military hardware, old telephone switching equipment and electronic junkyards.


    Reply 10 years ago on Introduction

    Are you sure you don't mean 40mm x 120mm, looking at the last photo, that must be the case. (40mm = 4cm = ~ 1 11/16")