I have an existing setup for reflow soldering using an oven, Arduino, thermo amplifier & thermo couple.
Can I use the same setup with my hotplate (laboratory quality) or do I have to introduce other hardware to the equation. I'm thinking of using it for smaller jobs, not complete pcb reflows.
One area that I am not sure about is that my oven incorporates & requires a timer for reflow soldering to work but the hotplate does not have a timer. The hotplate is problematic in that, on its own, it takes a relatively long time to reach target profile temperatures (and something like 20 mins to reach 225C).
I would appreciate your help and/or to point me to an existing instructable, or similar. I'm thinking the Arduino might not be the way to go for the hotplate.
My only thoughts on the subject is that a ramp & soak PID controller might be the answer. An issue might be whether the hotplate is able to cope with a PID controller that speeds up the profile to a significant degree, which would be the case in this instance.What do you think?
If you believe it is not feasible for external control of the hotplate please let me know. Having said that many of the more expensive laboratory hotplates come with built in controllers, but I do not know if they accommodate ramp & soak.
I turns out my analog hot plate only has a capacity of 350 watts. That will never do for achieving a reflow profile. No wonder it takes so long!
it gets worse-was sold new as 350 watts but its CE sticker says it's only 200 watts. And what's more it's already PID controlled, so a 2nd one is out of the question.
dalpets:
I turns out my analog hot plate only has a capacity of 350 watts. That will never do for achieving a reflow profile. No wonder it takes so long!
it gets worse-was sold new as 350 watts but its CE sticker says it's only 200 watts. And what's more it's already PID controlled, so a 2nd one is out of the question.
Just thinking aloud guys
Besides, the hot plate is busily heating the wrong side of your circuit board. I assume you are placing it with the components on top.
Is your "oven" a toaster oven with heat on both top and bottom? Easiest solution is to get a temperature probe for your DVM and use it to manually monitor the temperature. You will be there watching the process, so may as well control the temperature at the same time. You may even be able to solder double sided boards.
I use a low wattage cooking hot-plate set to ~200C (I use a blob of old solder as temp indicator).
Put the circuit board on there for about three to four minutes.
Then use the hot air of a reflow station (set to ~250C) to flow the components.
Then slide the board off onto a cooling rack.
Leo..
Paul_KD7HB:
Besides, the hot plate is busily heating the wrong side of your circuit board. I assume you are placing it with the components on top.
I tried it out on a learner's smd board with paste and it worked OK for 0605, 0805 &1206 for capacitors & resistors, monitoring temps as best I could. Although the heating was out of step with the standard reflow soldering regime the smds took OK & values weren't compmpromised on a before & after basis, but IC's may be a different story
Paul_KD7HB:
Is your "oven" a toaster oven with heat on both top and bottom? Easiest solution is to get a temperature probe for your DVM and use it to manually monitor the temperature. You will be there watching the process, so may as well control the temperature at the same time. You may even be able to solder double sided boards.
Paul
Yes 2 elements both top & bottom. I've been using a separate thermometer to monitor the arduino serial momitor
