I admit it: I'm a total geek. I love electronics, programming, 3D art, vintage Apple hardware, and whisky. I'm always juggling half a dozen projects. I also enjoy documenting it all: my successes, my failures, my experiences... and everything geeky along the way.


 
 
 
 
 

DIY Reflow Oven - Part II | Kevin Rye.net - Main

Kevin Rye

Geek Extraordinaire. Yeh, I said it.

DIY Reflow Oven - Part II

With a free weekend, and all my piece-parts ready to go, it was time to get my build on.

diy_reflow_oven_1005

First up was taking the oven apart to expose the innards, and cutting away at the old wiring.

diy_reflow_oven_1006

I lined to interior of the oven with Reflect-A-Gold. I didn’t think I was particularly wasteful with the 18’ roll that I had, but I somehow managed to run out before the job was done. I didn’t have any left over for the glass door.

diy_reflow_oven_1010

Needless to say, I had to jump on eBay and order another roll to finish the door. Man, this stuff is expensive!

diy_reflow_oven_3001

I then drilled all the necessary holes and mounted the ControLeo2 enclosure.

diy_reflow_oven_1011

I could have done a better job of lining up these holes. It looked better before I drilled them. I guess the drill drifted off-target a little.

diy_reflow_oven_1008

Instead of attempting to solder thick gauge wire onto the back of the DC power supply, I opted to drop $1.50 on a DIY AC socket.

diy_reflow_oven_1013

So much cleaner, and it’ll be easier down the road if I have to replace the adapter. I then finished all the high-voltage wiring to the top, bottom, and boost elements.

diy_reflow_oven_1014

Next up was the low-voltage stuff.

diy_reflow_oven_2014

Here’s the ControLeo2 controller. Pretty nice piece of kit for $64 bucks.

diy_reflow_oven_3002

diy_reflow_oven_3003

I then ran the wires for power, the thermocouple, the servo, and the relays through the back of the enclosure and connected them to the controller.

diy_reflow_oven_3004

It was a tricky trying to hold the standoffs in place while I threaded the screws, so I used a little hot glue. Everything fits perfectly.

diy_reflow_oven_3006

Power is good. The outputs are good.

diy_reflow_oven_3008

With that, I buttoned up the controller and moved onto the servo.

diy_reflow_oven_3013

I mounted a small piece of aluminum to the door handle so that the servo could open the door.

diy_reflow_oven_3021

It’ll open the door about an inch when the reflow is complete, and close when it’s cool.

diy_reflow_oven_3020

Lastly, I installed the PCB tray.

diy_reflow_oven_3022

Awesome. I can’t wait to fire it up.

diy_reflow_oven_3026

When you first attempt a reflow, ControLeo2 will enter Learning Mode. It will attempt to tweak the oven's heating elements in order to conform to the J-STD-020 standard. If the temperature rise is too fast or too slow, the cycle will be aborted. ControLeo2 will make some adjustments and save them into the EEPROM for the next cycle. You let the oven cool down, rinse, repeat.

You basically keep doing that until the temperature rise meets the J-STD-020 standard. ControLeo2 will then leave learning mode and you're all set. According to the Build Guide, ControLeo2 could nail it on the first try, or it could take up to 20 cycles. I got lucky. My oven figured itself out after 4 cycles.

I grabbed an old scrap board and applied a small blob of solder paste to each pad.

Reflow_test_0004

I then placed some resistors on the pads.

Reflow_test_0005

I placed the board within the oven, and let 'er flow.

Reflow_test_0007

It only took a few minutes. It's a pretty quick process. I didn't bother timing it, but I'd have to say it was about 7 minutes. The longest part of the process is waiting for it to cool down. You definitely want to do this outside, it does get a little smokey toward the end of the cycle. You don't want that in the house; especially if you're using lead solder.

All-in-all, this was a pretty involved build, but the results were well worth it. The board came out amazing; way better than I could ever do by hand.

Reflow_test_0009

With the oven good to go, I decided to try soldering a MAX6921 to a breakout board. This has to be the finest pitched chip I’ve ever seen. It came out pretty good despite a few bridges. I had to clean them up with some solder wick. It’s going to take a bit of practice before I can properly gauge how much solder paste is too much.

Reflow_test_0014

See this project from start to finish:
DIY Reflow Oven - Part I
DIY Reflow Oven - Part II