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Re: Reflow Fred Style! :-)

Posted: Sun May 20, 2012 7:10 pm
by Fred
A few pics to illustrate just exactly how hot it got in there...

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So I decided to make the baking tray for the PCBs out of the alloy (this is where Abe got all upset).

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But it didn't fit properly, because I'd put too much glass fibre insulation in between the layers.

And the heat made it bow from expansion anyway, so I "fixed it" (pun intended) with a couple of screws.

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And called it good. Tune in next time for the high-tech electronic side of the modifications! :-)

To be continued...

Fred.

Re: Reflow Fred Style! :-)

Posted: Sun May 20, 2012 7:30 pm
by Fred
As you may recall, I baked the thermocouple IC first, by feel.

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First I dismantled the thermocouple and recorded the polarity of the cable going
into the plug by orientation of the printing on the shrink sleeve.

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Then I loaded up the schematic and started getting artistic with components! :-p

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Things seemed to be going well, so it was time for the first cold-on-hot-off-cold test! :-)

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The circular thing on the little circular PCB is a piece of solder so I could tell when it was hot enough.
I didn't actually get a reading from the thermocouple this time around, so I killed it before it got hot.

To be continued...

Fred.

Re: Reflow Fred Style! :-)

Posted: Sun May 20, 2012 7:42 pm
by Fred
After some scratching of my head, and chatting to DeuceEFI on IRC, I realised that I had
simply been ignorant and ignored a crucial but unimportant-looking part of the schematic.

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In the process my thermocouple wire got shortened a significant amount :-)

But, it was time for another test!

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This was the noisy test that I posted earlier, but largely a success.

The thermocouple wire insulation showed signs of being plenty hot.

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And the noise meant that I thought I'd follow the schematic even more closely and add some filtering.

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Plus, the expansion forced the door partly open from about 200C up, so I fixed that too.

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It must be time to control it! :-)

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I don't have the rest of the pics handy right now, but I'll try to find them and do another post soon.

To be continued.... but not today! :-)

Fred.

Re: Reflow Fred Style! :-)

Posted: Thu May 24, 2012 12:18 am
by Fred
viewtopic.php?f=9&t=1621 < johntramp, now it is! :-p

Re: Reflow Fred Style! :-)

Posted: Sat Jun 02, 2012 12:38 am
by Fred
How many people bugged me about these pics? How many of those commented at all? Poor form.

Today the oven baked another tcouple IC. Tonight I have two working and tested. Tomorrow I might do some experiments!

Re: Reflow Fred Style! :-)

Posted: Sat Jun 02, 2012 4:31 am
by ToxicGumbo
Fred wrote:How many people bugged me about these pics? How many of those commented at all? Poor form.
I was skeptical about the need to insulate and double plate the unit, but you sure as hell have it down to a predictable state, which is nothing short of impressive.

You need to come up with a logo, such as:

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Oops...wrong image. Maybe more like this:

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Re: Reflow Fred Style! :-)

Posted: Sun Jun 10, 2012 2:02 am
by johntramp
Classic. Do you think the insulation helped much? And have you tried your slice of bread heat distribution test again with the alloy plate?

Re: Reflow Fred Style! :-)

Posted: Sun Jun 10, 2012 6:16 am
by Fred
johntramp wrote:Do you think the insulation helped much?
Yes, a LOT. You can almost touch the top and back with the inside @ 300C now. Before you couldn't get closer than about 10cm from the back - the radiated heat was too much.
johntramp wrote:And have you tried your slice of bread heat distribution test again with the alloy plate?
No, but that's a stellar idea! If we obtain another bimbo for thorough use, I will commandeer some for this purpose.

Re: Reflow Fred Style! :-)

Posted: Wed Jun 20, 2012 2:05 am
by Spudmn
Hey Fred. I thought that you might like this. :lol:

http://hackaday.com/2012/06/18/toaster- ... overboard/

Re: Reflow Fred Style! :-)

Posted: Wed Jun 20, 2012 8:59 am
by Fred
LOL :-p

The actual link, for those wishing to short cut Aaron's trickiness ;-)

http://hobbybotics.wordpress.com/projec ... ler-v8-03/