Rework station pcb design

[pintglass]

Hi

I'm in the early stages of trying to build myself a rework station so I would like to keep things as simple as possible and also within reason cost wise.

Whilst doing some research on what others had done i came across a design that had been done in fritzing which i have attached. The person who designed this seems to have abandoned it as I am unable to contact him.

I couldn't get on well using fritzing so i have created a schematic from the fritzing layout.

There's quite a few component values that I'm not sure about, but for now if you guys can cast your expert opinion on whether I've draw the schematic correctly that would a great help.

[sam_sam_sam]

Can I ask for the reason you want to design and build a rework station

Because you have struck some interest in me about this question about building one

[pintglass]

I've wanted to build one for ages's but never found the time, I mess around repairing game consoles and mobile phones so it would mainly be for that.

This is just a hobby for myself so an other reason is i enjoy making things and learning from it. At the moment I was just looking for some advice as to whether I've draw the schematic correctly, and as the original design is from an other hobbyist a bit of reassurance that the circuit wouldn't have any major issues, mainly on the A/C side.

[budm]

Do you know if the actual circuit is built and tested?
The TRIAC Gate drive/snubber R5 of 2.2K is way too high.
Read and study the ST application notes attached.
Power supply filter caps C5, C7 should be hihger value.
You should also have the 0.1uF ceramic close to VCC pin of each IC.
Thermo couple measurement circuit is also very questionable.
How well do you want to maintain the tempearture?
Study here:
https://www.analog.com/media/en/tech...otes/an28f.pdf
https://www.analog.com/en/analog-dia...ocouples.html#
https://www.youtube.com/watch?v=5aFSLzeLQ6c

[diif]

Originally Posted by pintglass

I've wanted to build one for ages's but never found the time, I mess around repairing game consoles and mobile phones so it would mainly be for that.

This is just a hobby for myself so an other reason is i enjoy making things and learning from it. At the moment I was just looking for some advice as to whether I've draw the schematic correctly, and as the original design is from an other hobbyist a bit of reassurance that the circuit wouldn't have any major issues, mainly on the A/C side.

Consoles with large thick PCBs are very different to small delicate mobile phones.
I wouldn't even think about putting a phone on my Scotle (clone?) BGA rework station, it's far to large and powerful. I think you need to decide if you're making it for console/tv/laptop boards which will need a large bottom heater and large hot air/IR nozzle or for phones which will be a lot smaller and won't need nearly as much power.

[pintglass]

Originally Posted by budm

Do you know if the actual circuit is built and tested?
The TRIAC Gate drive/snubber R5 of 2.2K is way too high.
Read and study the ST application notes attached.
Power supply filter caps C5, C7 should be hihger value.
You should also have the 0.1uF ceramic close to VCC pin of each IC.
Thermo couple measurement circuit is also very questionable.
How well do you want to maintain the tempearture?
Study here:
https://www.analog.com/media/en/tech...otes/an28f.pdf
https://www.analog.com/en/analog-dia...ocouples.html#
https://www.youtube.com/watch?v=5aFSLzeLQ6c

Thanks for all the info.

According to the guys hackaday page he has tested it but I don't know to what extent.

https://hackaday.io/project/10541-di...rework-station

I would like to maintain the temperature as accurately as possible which i don't think this design will allow. I'm looking into changing the thermocouple circuit.

[pintglass]

Well I've been reading as much info on this as I can, but being honest alot of it goes over my head.
Anyway I was just going to order a few parts to have a mess around with but I'm unsure on the voltage rating of the ceramic snubber caps C1, C2 in my schematic.

Should these be rated for my line voltage peak?

[sam_sam_sam]

You one of each of the following

https://www.ebay.com/itm/NEW-LCD-Dis...EAAOSwXRleLK3W

And one of these

https://www.ebay.com/itm/New-Part-So...QAAOSwmdtd5Y2a

If you decide to use both of these items

Please let me know and I will help you hook it up

[sam_sam_sam]

I thought about doing the same thing


If you buy one of these units
do a mod to and do a way with
air hose and pump and buy the soldering
iron and use the temperature sensor in it

Hook up you heater setup in place of the air pump and the heater in the handle

You would have a good temperature controller

ZD-939L


Hot air repair/rework stationwith LCD Display.
Features: internal air supply, stable temperature, comfort grip handle, interchangeable hot air nozzles for SMT devices.
LCD Display: "SET" Temperature & "Actual" Temperature of Nozzle
Selectable "C" or "F" Readings
Specifications:
Voltage: 110-130VAC 60Hz
Power input: 320W
Adjustable Air Flow: ~22L/minute(max)
Adjustable Air Temperature 150-500deg "C"
Sensor: Type K Thermocouple
Air Pump: diaphragm
Hose Length: 1m
Accepts most 22mm Nozzles.
Supplied Nozzles: ~10x10mm, 14x14mm, 2.5mm Dia & 4.5mm Dia.


You buy it here

https://m.reichelt.com/de/en/digital...LE=161632&&r=1

[pintglass]

Thanks for the idea, but I don’t see how you would be able to control the rate of rise of temperature with this setup

I’m still doing more reading than anything at the moment and just making a circuit to use a
Ad8495 temperature ic which I think will be better than what I had in my schematic.

[diif]

I'm not able to see how a hot air station that's 320W can control a 600W top heating element.

Why not buy a PID controller, relay and thermocouple ?
https://www.ebay.co.uk/itm/220V-NEW-.../173982370797?