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Best Re-flow Oven for Hobby electronics
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Brumby:

--- Quote from: Doctorandus_P on April 07, 2019, 04:04:42 pm ---Simon says .....

--- End quote ---

Made me smile.  :-+
Simon:
Yea, infrared = light, things absorb heat and light differently based on colour and texture. Just had an IR thermometer thrown out at work that they were using for measuring hot water :palm:
wilfred:

--- Quote from: jmelson on April 08, 2019, 02:42:43 am ---
My first test was with the thermocouple in air.  The boards burned while the temp indicated 230 C or so.  So, obviously, the boards absorbed more IR than the thermocouple.  Next test, I poked the thermocouple into a plated through-hole in the board, and got beautiful reflow soldering.  So, unless you attach the thermocouple to some kind of PC board simulator that has well-matched IR characteristics, you won't get the right temperatures.

Jon

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Thanks Jon. I'll keep that in mind.
I wanted to avoid fitting the probe into a board each time. I think I might try embedding it into a square of PCB material about 4cm and fixing that to the wire shelf. I've got a tube of Selleys Sealfix that I was going to seal any gaps up with. Maybe I could use it to glue the probe tip to the copper. Just floating ideas here. Stop me if it is stupid. I don't think I'll need to seal gaps up though. The small size of the oven seems to work well getting the heat only 5cm from top and bottom sides.

http://www.selleys.com.au/adhesives/household-adhesive/task-specific/seal-fix/
Doctorandus_P:
I think it is a combination of having a reliable and adjustable temperature profile in combination with some experience and experimentation.

Being able to generate a repeatable temperature profile in the oven is one part of the equation.

Some use loose thermometers, which can be clipped to the PCB, but if the thermometer is in a fixed position then there wil (hopefully) be some fixed and repeatable temperature difference between the thermometer and the board itself.

On the first board this temperature difference is unknown, which is where it becomes handy to be able to live monitor the soldering process.
Based on previous experience you make an educated guess, and then tweak it a bit in time or temperature untill it works for the PCB to be soldered.

There are also a lot of reasons for temperature differentals in the oven, which makes soldering more difficult.
Compare black (good IR absorption) and shiny (Reflect IR) components.
Some thick components can also take more time to heat than other thinner components.

I've heared some success with usig a frying pan with a layer of fine clean sand, which heats the PCB evenly from the underside.
The sand has a high thermal mass, so you probably have to use a plier to take the hot PCB out of the sand to prevent overheating.
Nasdrasil:
I know it's been a while in this topic, but I am looking for an oven too. So far the experience has been no fun at all. I quickly discovered there are not a lot of reviews and there is not a lot of info on the cheaper chinese machines. From what I read I should try to avoid a T962. I did just that and found that the qs-5100 was a model that showed some promise. I ordered one from Aliexpress, only to find out they shipped me a T962 with a frontplate that says qs-5100. Did the model change over time? The firmware that my "qs-5100" has is exactely what is on a T962. My "qs-5100" has two green lights instead of red ones, just like a T962. It also has the infamous masking tape. Looks to me like at some point they just changed the qs-5100 to use T962 hardware and hoped people wouldn't notice. Anyway... I shipped it back (which was not cheap) and ordered another one in another Ailexpress shop. Totally exited I came home after a crappy day of work. I knew it had arrived. I open the box and... THESAME darn thing! They clearly show on their store they are selling the qs-5100 that I see reviews of on the web and youtube, but whay they shipped me is AGAIN a converted T962. Just as a heads up to anyone ordering a qs-5100 through Aliexpress... be very alert to what they ship to you. Anyway... for me the qs-5100 is not an option anymore. I did find the T962a+ and I don't know if that is a new model or something, but it has almost no reviews. Some people were saying that it took care of some of the problems the T962(a) has. It also features a usb connection for programming profiles, which is supposed to work on Windows 10. Anyone with some experience on this particular model? What do you guys think?
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