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Have a good idea for a new product for SFE or Olimex? Let us know!
By corvette123
#42620
hahaha i hijack threads all the time :)

ok back on the thread..


making a new reflow controller, based on the dspic....

will have a mini thermocoupling connector (done right :) )

40 mips dspic.

USART
I2C LCD
keypad connection upto 10 pin
fan out
relay out
optional outs.

all surface mount in a 2"x2" package.

should be pretty nice...

look for it soon :)

we are still selling our current reflow controllers comes with free software

www.thesiliconhorizon.com

stop on by and buy one or two :)

cheers :)
By Heffo
#42809
I had a thought. Why not build into the oven's controller, a mode to keep the oven at a constant 125 Deg Celcius for a period of 24hrs or any other temperature and duration required. That way you can bake moisture sensitive RoHS components before reflowing.

The manufacturers seem to be pretty insistent about the baking of components exposed to air for too long, so there must be something to it!
By corvette123
#42813
hahaha :p

soon the firmware will be open to modify as you like...

and that is an easy hack to do to the firmware..

although as a company i dont think anyone in their right mind would release that way becuase someone would burn down their house and sue them.

:(

but if they hack it themselves to do it, then burn down their house... well..... then its their own fault ...

:? :? :cry: :cry:
By Heffo
#42815
corvette123 wrote:as a company i dont think anyone in their right mind would release that way becuase someone would burn down their house and sue them.
Well, I am not sure how the law relates to electrical appliances in the USA, but over here in Australia, it's pretty-much illegal to make any modifications to mains wiring in a house, appliances and so-on if you aren't a qualified electrician or electrical contractor. So in effect, modifying a toaster oven to work as a reflow oven is illegal. Sure, the police aren't exactly going to arrest you for it but if you go and do something stupid like burn your house down, then try to sue the manufacturer of the conversion kit, you would get thrown out of court. (most Australians don't sue anyway, too american, we just claim compo instead :lol: )

Besides, 125 Degrees C isn't really all that hot. Sure, it'll burn you pretty quick, but it's nothing compared to 400 Degrees C, and if the oven is designed to run that high for a few hours, 24 at 125 should be easy.

If I was the one designing the software though (which I do professionally anyway) I would have a few very large, flashing, warning screens the user would have to click-through, aswell as a disclaimer and liability waver that must be agreed to before the option to run as a baker would be enabled.

I also tend to think that there would be an element of safety involved too. Since there is a thermocouple in the oven reading the temperature, and the controller board regulates the heating element based on the temperature, set the software to shut the element off completely if the temperature inside the oven increases over 10% of the target temp. That way, if things start to run away, you can shut down the heat before things start burning.
By propellanttech
#42823
Heffo wrote:I had a thought. Why not build into the oven's controller, a mode to keep the oven at a constant 125 Deg Celcius for a period of 24hrs or any other temperature and duration required. That way you can bake moisture sensitive RoHS components before reflowing.

The manufacturers seem to be pretty insistent about the baking of components exposed to air for too long, so there must be something to it!
What I find surprising is the reason they back the parts. It is claimed that the parts need to be dried as a result of the higher reflow temperature. The moisture in the chips can cause them to explode at the higher reflow temperature.

Now if you ask me .......their exploding was just as "probable" at the lower temps of lead solder.

Really I guess it does make some sense, but I find not all parts require a bake. If you do keep your parts open to the air, I suppose it would be a good idea.

But this is my opinion,

James L
By corvette123
#42920
i havent had any parts explode yet... ive been working with 4 and 6 layer boards with 2 sided SMT for months and months and months and months now!! and have had great success with my black and decker infrawave.

illegal to modify a toaster oven? hmm i seriously doubt that one!.. now you should have an electrician modify your house wiring yes that needs to be licensed and such.... but have you seen some of the things hobbyists hook up?? look on youtube where people build CNC lasers in their house and have gas bottles in the basement...... hobbyists are crazy hahahaha.... but its fun. i think its good for people to do their research and know if they know enough to do it safely. if they cant then get someone who can. that is a good stance on the matter. dont scare people out of the hobby however.

currently our software shuts down the oven automatically at 10 minutes time just for safety....... that can easily be change to 24 hours or whatever.... so modifying the firmware to function longer is simple as changing one variable.

yes i have seen a few parts require the "drying" for extended period of time and thats why we will be offering the firmware sourcode for people to modify that themselves and thus the liability rests on them.

i think the nag screen when the program starts is an excellant idea for liability issues for these types of controllers, and should be added. thanks for the idea.

8) 8) 8)
By Heffo
#42921
corvette123 wrote:illegal to modify a toaster oven? hmm i seriously doubt that one!.. now you should have an electrician modify your house wiring yes that needs to be licensed and such.... but have you seen some of the things hobbyists hook up??
Oh, it's legal to modify the electronics on the low-voltage side of your mains transformer. Anything that is connected directly to the AC mains supply is licensed electrician domain. So, going an adding a solid-state-relay or even a regular old relay to the wiring in a toaster oven is technically illegal here.

And don't worry, I have been disregarding that law and doing all my own mains wiring for years!

Actually, as a side-note, you can do mains work yourself, so long as you have a licensed electrician/contractor check over the work and issue you a "Certificate Of Electrical Safety" saying the job was done right.

I know all about what hobbyists hook up, I do it myself!
By corvette123
#42928
Heffo wrote: And don't worry, I have been disregarding that law and doing all my own mains wiring for years!
hahahahah i like u already !!

:lol: :lol: :lol: :lol: :lol:
By corvette123
#44565
ok version 2 of the reflow toaster oven controller is tested out!!

will be rolling out boards really soon!!

revamping software and prettying it up to release the source code for everyone to use and modify with this controller.

so the specs on it are:

standalone or computer operation!!!
small 2"x2" size
18f4553 12 bit A2D at 12 MIPS 48 Mhz.
AD597 thermocouple amp for K type thermos
256K eeprom 1 Mhz I2C
USB bootloader (no programmer needed)
ICSP port for programmer
I2C port for matrix orbital display and keypad together
UART port for a serial LCD for cheap LCD solution
keypad 8 pin header when using the UART LCD solution
4 user IO's for adding switches and whatever
usb 2.0 mini jack
2.1mm dc power jack
screw terminal blocks

and of course our free software with full source code!!!

heres some screen pics of an interim firmware, a custom PID with full on / off driving at 2mS period

we will have a full tradition PID driving PWM firmware also but the above firmware works really really good!!!

both have adjustable gains in windows GUI.

the GUI is written in visual c#.

anywhoo heres the pics

this is our "no burn" profile following shenmao, and manncorp solder paste profiles. pid gains at 1,0,3 on our black and decker infrawave 1300 watt oven

Image


this is a zoom in of the graph showing the most deviation we got for the steady state... about 1 deg celsius.... not bad!!!! our parts give us + / - 5 deg celsius so we are happy with the results!!!

Image


:D :D :D :D :D
By corvette123
#44568
heres some pics of the test setup...

ok im not good at metal work so no jokes there !!! hahahah

:oops: :oops: :oops:

this platform was based on our reflow v 1 controller.... so thats why i have the new one kinda hanging on the air...

:P :P

using a matrix orbital I2C LCD and keypad.



Image

Image

Image
By corvette123
#44569
the new version will be much cheaper as we are using alot less expesnive parts.

im gonna try and get it distributed here at sparkfun at a discount price :) will email them

:D :D :D :D
By tecfacet
#47530
i would be interested in the new dspic version of the controller.

i have to make the leap soon.
By corvette123
#47615
hello

we went with the 18f4550 chip.

it works wonderfully as you can see in the graphs!!

we have a steady state variance of like 2 deg at most. (even 1 deg C sometimes...)

so very happy with the new reflow 2.0 controller!

:D :D
By corvette123
#47978
weve updated our software!!!

our reflow controller now supports profile creation (3 stage ramp and spreadsheet) upto 2 days in length!!!!!!!!!!!!!!!

you can also do 3 stage ramps standalone without a computer on the fly from a keypad...

what you gonna do with a 2 day profile for running your toaster oven?

well you can use it to dry components...

you can also use it to cure certain types of composite materials.

many additional uses beyonf the simple reflow oven!!!!

:D :D
By propellanttech
#48001
corvette123 wrote:weve updated our software!!!

our reflow controller now supports profile creation (3 stage ramp and spreadsheet) upto 2 days in length!!!!!!!!!!!!!!!

you can also do 3 stage ramps standalone without a computer on the fly from a keypad...

what you gonna do with a 2 day profile for running your toaster oven?

well you can use it to dry components...

you can also use it to cure certain types of composite materials.

many additional uses beyonf the simple reflow oven!!!!

:D :D
You know what I'm looking for.

An oven with a controller that will keep a constant 125 C internal temperature, with a timer that will turn the oven off after a set time (48 hours).

The key here is the internal dimension must be about 13 inches wide, and about 10 inches deep.

James L
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