T-962 Reflow Oven Custom Profile Calculator | Voltlog

[@trickyrat483]

Excellent video. Would be nice to see your calibration work and test results afterwards, to know if the oven can ultimately be trusted to follow heating profiles correctly.

[@voltlog]

Ultimately I think it's gonna take some work to get it to match the profile.

[@miharix]

I also made all the T-962 modification (+ fan upgrade) years back. To maximize and optimize its surface, I found out that PCB reflows better if its lifted higher from bed. Use old PCB on corners or if you have mounting holes in PCB use M4 screw + nut + 2*washer the nut, the screw method works great for reflowing multiple batch (M4->washer->bed->washer->M4 nut->PCB)

[@voltlog]

Yeah since this is IR, it works better if you bring the PCB closer to the elements however it does have the disadvantage of getting less even spread of heat across the pcb, meaning you might get high temp spots. What I think helps though is to get the PCB off the metal tray which is sucking some of the heat away through the bottom.

[@CoryCharlton]

Just received my T962-A recently and performed the cold junction, tape, and thermocouple amplifier upgrades. I found it much easier to modifying the firmware in order to add/change reflow profiles than enter them manually. It should also be possible to set a custom profile through the serial interface so I'm looking into that.

[@ristomatti]

I was watching this on the side while typing a message on my phone. My focus instantly shifted when the sloth crept on screen. 😂

[@denishraju]

Thanks for the Google Sheets, it really helps.

[@dd884e5d8a]

Minor nit: it’s interpolation not extrapolation in this case. Thank you for the nice video!

[@voltlog]

Thanks for that!

[@lasersbee]

Would have liked to see the actual inside temperatures compared to the curve temperatures requested. Thanks for showing how to input a custom curve.

[@voltlog]

That is better shown in a video where I talk about calibration because the reading will vary with factors like: calibration, cold start vs warm start. But I don't think I'll be doing any more videos on the subject, these videos get very few views.

[@C00ltronix]

I have T-962A with the modified firmware. I use Sn99AgCu0.3 - my profile works perfectly on small PCB (35 x 50mm) - but fails on the panels of same ) 2x2 - 70 x 100mm. On some joints you still see the paste's solder ball structure. Seems also the heat distribution inside the oven is not even. Anybody has a working profile for Sn99AgCu0.3 ?

[@tengelgeer]

4:00 Although very inconvenient, the oven does seem to show set points at +- 250 degree as a default value. Agree that the default should just be at 0.

[@voltlog]

While editing the video I noticed those points and I was wondering what do they mean 😂 Thanks for that. When I get a chance I'll have a look at the firmware to see if there is an easy fix for this.

[@ChrisFredriksson]

Do you have any updates on this oven in 2022? Still working? Are you using it? Any more mods or updates you've done or if there are any available? How do you vent the "fumes" from the oven? I'm thinking of using my Weller solder fume extractor, but at the same time I think the massive heat wouldn't be good for it.. kind of different compared to a "simple" soldering iron 😂😃

[@voltlog]

I'm constantly having trouble with uneven heating inside the oven so what can happen with bigger PCBs is that some components don't reflow at the end of the program. So because of that I don't use it that much. Things can probably be improved I just haven't had time to deal with this so I used my hot plate instead. I use my regular fume extractor to filter the fumes.

[@CoryCharlton]

@@voltlog this is the 800W version with only two lamps correct? I ask because I have the 1500W version with four lamps and it seems fairly consistent across most of the heating area.

[@voltlog]

@@CoryCharlton Mine has just two lamps, the basic model.

[@bogdan546]

I watched this video and I have a question about this reflow oven and hot plate 946C . Which is better?

[@jwrtiger]

Thanks for posting this informative video. I just received my T-962 and I am making the modifications you showed in the previous video. I am a big fan of Kester products and noted you used one as an example in this video. I was wondering if that is the solder paste you used and how you liked it? I have enjoyed following your channel for a long time.

[@voltlog]

I am fan of Kester products myself but I've only used their solder wire and fluxes so far. I'm sure the paste is great too it's just hard to obtain here in the EU.

[@AttilaAsztalos]

Can't stop reading that label as "Infraredi Cheater" (it's just too funny not to). As someone who has occasionally recorded multi-point PCB temperature profiles through a full-sized conveyor oven I can attest that actual values can be quite different from what the setpoints suggest, especially in areas where the copper geometry is doing something funny to the heat propagation (or supports are leeching out the heat). It's a right headache to get it reliably dialled in for sure...

[@electronic7979]

👍

[@MSM5500]

I think that is a mistake just to copy a graph from the solder paste datasheet to the oven controller as the graph from the datasheet is a MEASURED one (actual temperature) but the controller graph is an IDEAL one so it all omits the thermal dynamics occurring within both the oven and PCBAs inside of it. Instead of drawing complex curves in the controller I'd rather set just target start & end temperature points for each stage such as Preheat, Thermal Soak and Reflow then empirically adjust duration for each of them trying to keep it within the range allowed.

[@g.d.8065]

There's also a tool that lets you automatically plot points from a given image called WebPlotDigitizer (which also has a downloadable version despite the name): automeris.io/WebPlotDigitizer/ The way it works is you first define a set of axes, then you create an empty dataset for the points to fill, and you can draw on top of the curve to define an area that the program will plot points from. You an also erase parts of the mask if there's any overlap with other curves/grid lines that are the same color as the curve you want to plot. It has multiple algorithms for extracting data points. One of them lets you define a fixed interval and step size for each point (with or without interpolation), and it also lets you only record values within a specified output range. You can also plot points manually.

[@rokljhui864]

No. We want to set the custom profile without modifying the firmware.