SparkFun Forums

[angelsix]

The technique - Solder paste on SMD components, use temp controller hot plate, place board on plate. Warm up to 180 celsius over 2 minutes, hold at temp for 90 seconds, up to 210 celsius for 90 seconds, then turn off and let cool.

Just brought a temp controller hot plate and some bits today to try using SMD solder paste again. Spent time getting a board etched really well, placed all the components and paste ready to place on the hot plate, and as I cooked the board, I literally did cook it.... the copper boards I have are some fibreglass bottom, and some another material. Needless to say the one I used wasn't fibreglass and at 190 celsius it burned black!

The paste melted perfect and all component slid into place, however just before cooling down the material the board was made out of smoked and bubbled ruining the entire board. So a note to anyone else, only use fibreglass boards if you want to do the hot plate technique.

Anyhoo, I plan on doing the board again tomorrow out of fibreglass board and get some photos up. It looked really neat and tidy when I did it today... other than the board being bubbled and black so hopefully tomorrow it will be good.

[propellanttech]

The technique - Solder paste on SMD components, use temp controller hot plate, place board on plate. Warm up to 180 celsius over 2 minutes, hold at temp for 90 seconds, up to 210 celsius for 90 seconds, then turn off and let cool.

Just brought a temp controller hot plate and some bits today to try using SMD solder paste again. Spent time getting a board etched really well, placed all the components and paste ready to place on the hot plate, and as I cooked the board, I literally did cook it.... the copper boards I have are some fibreglass bottom, and some another material. Needless to say the one I used wasn't fibreglass and at 190 celsius it burned black!

The paste melted perfect and all component slid into place, however just before cooling down the material the board was made out of smoked and bubbled ruining the entire board. So a note to anyone else, only use fibreglass boards if you want to do the hot plate technique.

Anyhoo, I plan on doing the board again tomorrow out of fibreglass board and get some photos up. It looked really neat and tidy when I did it today... other than the board being bubbled and black so hopefully tomorrow it will be good.

Other materials do work, but there are some (like yours) which do not. Those require an oven.

Probably because you had a single sided board, the material was actually insulating the top from the heat. Etched boards do ok, but PCB's made by other means with through hole plating work better.

Also without a solder stop mask, it is harder to get PCBs to work well. The solder will tend to "run" down the traces connecting the pads.

James L

[angelsix]

Here is a capture of one of the components after re-doing the hot plate and paste technique. I must say its very good the end result is really tidy when using paste. Notice how the LED with 2 pins on one 0805 pad have seperated into 2 blobs of solder connecting to the resistor, using solder wire this would of just been one big blog. Looks cool

[ohararp]

angel six...it sounds like you kept your parts on the hot plate for way too long. I would ditch the the temp control. You'll find the insulation of the boards provides a very good profile. I sually set my hot plat to 400F on the dial and after it has warmed up after about 5 mins, then I will place my parts on the board.

[angelsix]

The board was only on for 3 minutes before burning. I redid it on fibreglass board no problem it was definately the material of the board.