Reflow Oven options - Page 1
Forum section: electronics / general

author: ARGLaser
author_rank: Contributor
timestamp: May 28, 2013, 01:37:19 am
content: Hey everyone,I'm looking for a reflow oven since I have a few large boards to assemble and it takes far too long with an SMT rework pencil. I've found a few toaster oven controller designs - but this is not ideal since the quality of the final product is dependant on the toaster oven and most of the tested brands of ovens can not be found here in Canada.I've seen the ovens on ebay, but I've heard poor things about the T-962.Is there some kind of a kit or pre-modded toaster oven I could buy?I would like to keep this under 250$ or so, but I am willing to spend more to get something that works.

author: c4757p
author_rank: Super Contributor
timestamp: May 28, 2013, 02:03:34 am
content: Quote from: ARGLaser on May 28, 2013, 01:37:19 amIt's a bigass power resistor in a metal box. What's there to depend on? Just get a nice, big high power one and slap a PID controller on it.

author: ARGLaser
author_rank: Contributor
timestamp: May 28, 2013, 02:46:29 am
content: I've read some can't increase the temp fast enough (2-3C / second)I'm open to suggestions, I guess I could always go to an appliance store with a thermocouple and test out the ovens before buying.

author: c4757p
author_rank: Super Contributor
timestamp: May 28, 2013, 02:55:52 am
content: Quote from: ARGLaser on May 28, 2013, 02:46:29 amMine's dreadfully slow (only 1 kW, about 1C/s) and it does just fine. If you're up for a real project get two (junk ones, if you can find them, or at leastonejunk one) and double up the heating elements. Obviously at 2kW you'll need more than just the standard 15A outlet (USA - assuming Canada is similar).It leaks a lot of heat out the front - I feel like I've been staring into the sun after watching it for a while - so maybe try insulating it. I'm assuming it's radiant, so maybe just some tin foil over the clear glass (leave a small window for monitoring).

author: ARGLaser
author_rank: Contributor
timestamp: May 28, 2013, 03:13:48 am
content: Sounds good! Any recommendations for a controller?

author: c4757p
author_rank: Super Contributor
timestamp: May 28, 2013, 03:27:22 am
content: Any old PID controller should do, unless you want it to follow an entire programmed temperature curve (in that case I can't make a recommendation). I just used a cheap one from Amazon and it's fine. Make sure you get a good quality SSR to switch it, though.

author: ARGLaser
author_rank: Contributor
timestamp: May 28, 2013, 03:53:31 am
content: I would ideally like to have the temperature curve. I have some ADC's that are touchy to heat, they don't like my reflow pencil very much.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: May 28, 2013, 08:33:09 am
content: Quote from: ARGLaser on May 28, 2013, 01:37:19 amYou'd be paying 20x that for a 'proper' reflow oven and so will need to improvise.You don't need to mess with PID controllers etc. The most important things are reasomably even heating (heaters top & bottom) and good visibility. Just add a simple power controller, and obviously don't use leadfree paste

author: Chet T16
author_rank: Frequent Contributor
timestamp: May 28, 2013, 09:00:31 am
content: Slightly related... My oven that I have to convert for reflow work doesn't have the heating elements on constantly even when set to full heat and it's heating up. Is this a safety thing or can I run them constantly when I change controllers?I would think it would be fine during the heat up stage? (currently it heats far too slowly)

author: tinhead
author_rank: Super Contributor
timestamp: May 28, 2013, 09:01:52 am
content: Quote from: ARGLaser on May 28, 2013, 01:37:19 amthe poot thing is the fact that none of the fans is beeing used for hot air curculation and that there is not heater forbottom side of the PCB (which is usefull sometimes, e.g. BGA)With DIY heater on bottom side and simple changes to onf of the fans (to allow circulation all the time), and of courseuser defined profile i was able to solder even BGAs, with no issues (except the typical 2zone only IR ovens)There is as well good replacement controller for T962 ovens,http://www.bernhardt.de/?Produkte:Hardware(search for "Steuerung Reflow32 für SMD Ofen T962 / T962A (und andere)"the devoloper asked about ~ 130USD for the controller, that not really cheap but it seem to work as described.Still, for BGA small heater on bottom side is necessary. So for something like 500USD you can get working solution.

author: mickpah
author_rank: Regular Contributor
timestamp: May 28, 2013, 11:24:00 am
content: For a PID controller I bought one of thesehttp://www.rocketscream.com/shop/reflow-oven-controller-shield-arduino-compatibleand a $20 arduino I had anyway.Now I just need to find time to try it out.The other items are an SSR from Iteadstudio (part of another order) and a cheap thermocouple from Jaycar.Only reason for the choice was price.Will post an update when I finally get around to putting it all together

author: c4757p
author_rank: Super Contributor
timestamp: May 28, 2013, 11:48:46 am
content: Quote from: mikeselectricstuff on May 28, 2013, 08:33:09 amI love the versatility of a PID controller because I can set it to literally any temperature above ambient. If I want to bake a board at 60C to dry it thoroughly after washing to remove old dust and crap, I can. If I want to preheat the board at 160C because there are TO-268s with high thermal mass and I want even reflow, I can. It's rather nice and only took a couple minutes to hook it up.

author: lgbeno
author_rank: Frequent Contributor
timestamp: May 28, 2013, 11:53:21 am
content: I think that you need 2 ovens, one for pre heat and one for reflow, that should make better joints.

author: ARGLaser
author_rank: Contributor
timestamp: May 29, 2013, 12:10:22 am
content: Quote from: mickpah on May 28, 2013, 11:24:00 amThanks for the info, I think I will do this.Do you think the digikey thermocouple 290-1911-ND will be good enough?