I want to build my own, just to see if I can.... I am starting with this fan:
It is 12 volt, .25 amp, rated at 8.5 cfm. Others have said the rating of the fan inside what they have is higher than Guru / Stoker rated it... So I went a little bigger than the 5 cfm I think my UDS will need.
I am going to build a housing to go over the 1" nipple already on Robot out of Aluminum diamond plate and .030 airplane skin scraps. I will insulate the connection with silicone sheet. I can test the fan / housing without a controller by using a 12 volt battery for a power source....
I am still deciding which PID / controller to start with. I may just buy the charcoal smoker controller from Auber Instruments for $75.00 that includes temp probe and power supply:
Or this fan should work with a guru or stoker if I decide to go that route...