Does anyone here own a Charmhigh BRTRO-420 reflow oven?

[TassiloH]

Hi all,

as the topic already says: Anyone here with a BRTRO-420 reflow oven who could share his/her opinion on that machine? Search only turned up the same question half a year ago, but maybe in the meanwhile someone has bought one?

My reason to ask: I am looking into buying a small reflow oven in the 500$ price range. I am only doing a handful of boards now and then, and right now I am using a modified hot plate, which works reasonably well, but lacks proper exhaust, one needs to press larger boards down, no proper temperature curve so flux activation/wetting is sometimes not as good as it should be etc. I don't really want to outsource manufacturing right now, because due to the low numbers I figure that would be more time spent doing coordination and specification than it takes to do the boards myself.

The really cheap ovens seem to lack power/uniformity (T962), or are IR-only which seems to make things quite sensitive to board placement (e.g. the T962-C descriptions read like there might be a circulation fan, but I have also found one post saying that they would like to add circulation so I don't know).

The BRTRO-420 description  (https://www.aliexpress.com/item/Hot-air-Infrared-2500w-Mini-Reflow-Oven-BRTRO-420-300-300mm-BGA-SMD-SMT-Rework-Sation/32747834351.html) clearly states a circulation fan, which hopefully should make the temperature distribution more even. The unit looks decent and would have just the right size for my needs (max boards 20x10xm). But any info from a real owner of the machine would be much appreciated!

Best,
Tassilo

[JPlocher]

It is a decent machine, and the fan does circulate the hot air...

...but, there are still cold spots around the edges - I fab 9x 4cm/4cm boards at a time, which fills the tray completely; the boards on the edges often have 5% - 10% "sintered-but-not-reflowed" connections, which increases inspection / rework time and effort...

The "windows" in the tray are pretty much useless

Adjusting the profiles with the LCD is a pain.

The exhaust fan helps with the first half of the cool down, but the 120degree to 50 tail takes a subjective forever.

My unit is 220v; I don't think they make a 120v version.

[TassiloH]

Thank you for your reply. This sounds like the little flaws and drawbacks that are to be expected if one goes shopping with a limited budget.

I have decided that I can live with the non-uniform heating if the tray is filled completely - my boards are typically <10x16cm, and if 20x10cm they have SMT parts only on a smaller area, I don't need to reflow more than one board at a time, reflow will not be limiting my throughput anyway. I also hope I won't need to adjust the reflow profile too often once a suitable one is found.

So I have pulled the trigger and ordered one today - should arrive within two weeks or so.

[asmi]

Please let us know your experience once you receive the unit and put it through its' paces. I'm also looking to upgrade from my old trusty T-962 as I need to be able to handle larger boards.

[TassiloH]

I have written down my experience, post is here:
https://www.eevblog.com/forum/manufacture/charmhigh-brtro-420-reflow-oven-review/