Just a quick update ... been super busy this week, work, furnace problems, and was waiting for parts anyways for the coils, and got accidentally side-tracked a little bit
Here's just a quick pic of something I started working on ...
Looking to build a custom enail that is really full featured but economical. This is screenshot from my phone of the running app ... the touchscren I’m still working on but UI will be the same essentially. Just some highlights:
- touchscreen display and mobile app
- wifi access (can configure wifi settings from touchscreen display)
- different PID tuning algorithms to get the best possible settings for your different nails etc being heated (or plates for a rosin press)—these algorithms are still a work in progress ... I’ve implemented some but also want to implement lambda tuning amongst others
- option to support multiple coils maybe as an option with ability to have different PID settings for each.
- ability to setup different PID profiles so as you switch from one device to the next you can change profiles so it is always tuned optimally for your use
I’m open to other suggestions as well. I’m also starting to consider some ideas on building a complete vape, but not sure I’ll get around to that
Aiming to make these so they could be $200 ... maybe less. Really depends on if I can get material costs down and if the beta product is deemed to be solid and stable.
Now i remember another detail!
@JCat mentioned he tuned his PID and set it to -55F, IIRC... That could allow for a slower coil heat up.
That last video was sweet!!
i did have the PID set to -55c at one point to make it accurate, but now with the modded coil it reads the SV3 temp and not the coil temp.
Pre-modded coil, it was running with the SV3 stable at 365F when the PID was set to 480F with no offset. No problems with a super hot coil. I’ve been running it a LOT. It’s been my exclusive and have been working a lot so often it’s been on pretty much straight for hours on end. It’s by far my favourite vape now and am missing it because I’m out of town right now!
Edit: to answer your question about the modded coil
@lazylathe, the location of the thermocouple has no relation to the heat output of the coil, except that the end temp is controlled. A PID will typically output at 100% of your coil output for the first bit of time to get it to heat fast, then will start cycling it on and off (this cycling is how it controls power % output as the coils don’t take variable voltages to control output ... they use PWM basically). So through this cycling it decreases the power as the set temp is approached. If going up it slows down the cycling to slow the heating so it doesn’t overshoot ... similarly when coming back down to temp it will start increasing the frequency (output) to get it to turn around as the set point is reached ... the PID settings (calculus) determine how steady the temperature is under various situations.
The location of the TC only affects where the set point is measured from. Either way I was setting the PID such that the SV3 thermo would get to the temp I want, so the PID would essentially be doing the same thing. The only difference now is I’m actually measuring the temp I’m interested in. Hope that explains it!
Also, you’ll notice with just your regular enail, the only time a coil gets red hot is in initial heat up. The reason behind this is that if you are heating up a nail, quartz banger, etc. The heater is at 100% output for the first ?minute? well you approach the set point. Once the set point is reached, it will only ever be on at 100% for seconds and will generally be at much less, often 0%, through the PWM cycling (you’ll notice the same behaviour on the elements on your stove too by the way!)
Not my first BBQ and I think my understanding of PID control and heating is sufficient to say this is ok
Whatever it is, it's gold Alexis! Gold! 
