Could this be the smallest and cheapest IR reflow oven? - Page 1
Forum section: electronics / general

author: Gyro
author_rank: Super Contributor
timestamp: October 08, 2017, 11:54:28 am
content: I was just idly browsing the EDN website when I came across this...https://www.edn.com/electronics-blogs/all-aboard-/4458627/Home-reflow-sees-the-lightUsing a low cost standard Halogen floodlight for both heat source and enclosure could be a bit dodgy but ingenious nontheless. Obviously only suitable for small boards but the temperature profile looks to be very controllable compared to the 'standard' pizza oven approach.The controller looks very neat and the whole thing obviously very economical and easy to build.May be of interest to someone anyway.

author: ebclr
author_rank: Super Contributor
timestamp: October 08, 2017, 12:04:15 pm
content: It 's a nice idea, simple and effectiveMore detailshttp://therandomlab.blogspot.com.br/2017/07/halogen-floodlight-smt-reflow.html

author: Yellofriend
author_rank: Regular Contributor
timestamp: October 08, 2017, 01:55:20 pm
content: The problem I see with that method is that it's based on light. So darker parts (i.e. ICs) will absorb more heat than lite color or shiny parts (solder paste). Best is IMHO something based on hot air.I have the legendary (bad) T-962, that is based on IR and pretty bad already (with the github mod I hope it's getting better)

author: coppice
author_rank: Super Contributor
timestamp: October 08, 2017, 03:05:58 pm
content: Maybe I missed something, but this thing seems to be directly radiating from the lamp to the board. There doesn't seem to be a mechanism to achieve an even temperature across the components. They are going to heat to a variety of temperatures, according to the absorption qualities and thermal capacities.

author: cdev
author_rank: Super Contributor
timestamp: October 08, 2017, 03:41:46 pm
content: I am on an old browser and it cant open the EDN page so I have to move to my main computer to see it.A countdown timer switch (like used in bathroom fans and hot tubs) might be helpful with a halogen lamp. That actually may be all somebody needs there. (If they already have a lamp)."Just don't let it sit there cooking away!" (without any control whatsoever, the components in the back would melt leading to catastrophic failure.) A controller is definitely the best way to go..Another option for home reflow and other kinds of soldering (preheating, rework) is the "946C" digital (temperature controlled) hot plate. I am going to do a writeup of mine soon. I paid under $50 for it.Its aluminum block is 200 mm square.Yesterday I used it with my hot air gun to replace some SMA connectors with different ones, it went really fast and no damage to components, including an SMD LED that was right next to one. Poof, done.(*Thank you @blueskull for the tip!*)Quote from: Gyro on October 08, 2017, 11:54:28 am

author: mairo
author_rank: Unknown
timestamp: October 09, 2017, 12:50:22 am
content: I do not see how this idea is cheaper and better (smaller maybe) than a AU$19 Aldi toaster oven.

author: bpiphany
author_rank: Regular Contributor
timestamp: October 11, 2017, 10:25:59 pm
content: Pre-owned toaster ~$5, Chinese SSR $cheap, a temperature probe and some practice =D Works ridiculously well. Put that on a fire proof surface, and mount the SSR to something of course..

author: nidlaX
author_rank: Frequent Contributor
timestamp: October 12, 2017, 06:26:12 pm
content: Quote from: bpiphany on October 11, 2017, 10:25:59 pmMakes me wanna try it with a gas stove and cast iron griddle.

author: Gyro
author_rank: Super Contributor
timestamp: October 12, 2017, 06:35:28 pm
content: QuoteI'm sure I saw a video on here somewhere of someone using a sand tray on a stove to heat the board - More even conduction without the thermal mass.

author: frog
author_rank: Contributor
timestamp: October 22, 2017, 03:07:10 am
content: I've had very good success with a $20 toaster oven. Mine has a glass door so you can watch for the paste melting, give it a couple of seconds and then switch off.Be mindful that toasters aren't designed to be operated on their sides, this may cause internal parts to overheat.

author: erikg
author_rank: Contributor
timestamp: October 23, 2017, 02:21:44 pm
content: On a related question: I've been under the impression that a convection reflow oven is a preferable option to an IR reflow oven for even heating and temperature control.Is this another reason a toaster oven would make a better reflow option?

author: ruffy91
author_rank: Regular Contributor
timestamp: October 23, 2017, 04:19:30 pm
content: IR will heat darker parts faster and convection will heat low thermal mass parts faster. Preferable would be a vapour phase oven, which will heat parts faster which are colder.

author: bpiphany
author_rank: Regular Contributor
timestamp: October 31, 2017, 06:17:30 am
content: Quote from: frog on October 22, 2017, 03:07:10 amThe subject of home built reflow ovens has hardly got much in common with using things the way they were supposed to.. It is a fair point though, and constant monitoring of the process would be advisable.Toasters are made to take quite a bit of heat though. During soldering operation the heating wires don't even hit glowing temperatures. With all plastic and electronics removed there's only metal and rock left in there anyway. Toasters are probably designed for vastly more intermittent use, but I've done soldering sessions well over the hour and several hundreds of cycles in total.

author: cdev
author_rank: Super Contributor
timestamp: October 31, 2017, 11:59:24 am
content: Using a powerful light to reflow reminds me of a popular children's toy here in the US when I was a kid.. an oven for children to pretend cook that used a light bulb.A heated aluminum block works well for heating small boards from below. Since the bottom of boards is where the solder is and where it needs to melt, that makes sense to me.I like it more than the other things I have tried for reflow because its open and I can see when the solder melts immediately.Also, I can use it as a preheater for rework, etc.An old convection oven- with a fan to circulate the heat has also worked okay for me.I've used a flashlight, from the outside to be able to see in to it. It does have a glass door however its still hard to see inside through it. I think that is the norm in cheap convection ovens. It would be ideal if it had a light inside.Some ovens have an internal incandescent light.