EzFlow Oven

RandleMcmurphy · March 22, 2020

I just got finished with my EzFlow Oven. This hacked toaster oven should make SMD assembly 'soooo' much easier. Caution, High voltage is involved. I added QuickChips temperature profile to the firmware, works amazing with the low temperature paste QuickChip has available.

I added heat resistant insulation to the internal gaps of the oven chaise, as well as the bottom of the unit to keep my desk cool.

The internally mounted solid state relay also has a large heat-sink mounted to it for heat dissipation.

(I should have took more pictures)

Big public thanks to RocketScream for providing a super affordable solution.

(Not Sponsored, I'm just weird)

Pics of Build

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Pics of SMD Test

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Links to Parts 'n' Stuff

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http://www.chipquik.com/datasheets/SMDLTLFP.pdf

https://www.rocketscream.com/blog/product/tiny-reflow-controller-v2/

https://www.amazon.com/dp/B0142SKL0Y/ref=cm_sw_r_other_apa_i_EITDEbP7WXMKY

https://www.amazon.com/TWTADE-SSR-40-3-32V-24-380V-Solid/dp/B079B63N3T/ref=pd_rhf_schuc_p_img_1?_encoding=UTF8&psc=1&refRID=SKG0BR5VB1VCJ0YA1JBT

https://www.amazon.com/Lynn-Manufacturing-Kaowool-Insulation-Fireproof/dp/B07ZQPX7Q7/ref=pd_rhf_schuc_p_img_1?_encoding=UTF8&psc=1&refRID=YK1YJWVYQENRYKRJMBB5

- I already had the toaster oven -

Ruffleduffle · March 22, 2020

the king of ghettorigs approves.

Question tho: how accurate is your temp-probe and can you calibrate for specific holding temps?

RandleMcmurphy · March 23, 2020

12 hours ago, Ruffleduffle said:

the king of ghettorigs approves.

Question tho: how accurate is your temp-probe and can you calibrate for specific holding temps?

The probe is pretty accurate, I was using a 'turkey thermometer of science' to compare the readings during testing.

The schematic and code are opensource, here's a pic of the thermocouple interface. Its based around the MAX31856.

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https://github.com/rocketscream/TinyReflowController/blob/master/TINY-REFLOW-CONTROLLER.pdf

As far as calibration goes... your gonna have to dig into the arduino sketch. I was able to change a few definitions for a quick and dirty temperature profile that was close to the QuickChip specs. I'm pretty happy with the results, but I plan on heavy code modification when I have the time. I suggest poking around in the source code, I would look around lines 178-215. I'm still trying to figure out how the PID was setup/tuned.

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// ***** CONSTANTS *****
// ***** GENERAL *****
#define VERSION 2 // Replace with 1 or 2

// ***** GENERAL PROFILE CONSTANTS *****
#define PROFILE_TYPE_ADDRESS 0
#define TEMPERATURE_ROOM 50
#define TEMPERATURE_SOAK_MIN 90   //QUICKCHIP
#define TEMPERATURE_COOL_MIN 100
#define SENSOR_SAMPLING_TIME 1000
#define SOAK_TEMPERATURE_STEP 5

// ***** LEAD FREE PROFILE CONSTANTS ***** //QUICKCHIP
#define TEMPERATURE_SOAK_MAX_LF 130
#define TEMPERATURE_REFLOW_MAX_LF 165
#define SOAK_MICRO_PERIOD_LF 9000

// ***** LEADED PROFILE CONSTANTS *****
#define TEMPERATURE_SOAK_MAX_PB 180
#define TEMPERATURE_REFLOW_MAX_PB 224
#define SOAK_MICRO_PERIOD_PB 10000

// ***** SWITCH SPECIFIC CONSTANTS *****
#define DEBOUNCE_PERIOD_MIN 100

// ***** DISPLAY SPECIFIC CONSTANTS *****
#define UPDATE_RATE 100 //QUICKCHIP