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aloon15
- 23rd September 2014, 18:45
Has anyone out there had any experience with the T-962 oven. I have seen them on ebay and the shipping charge from Ca. is about $100 which seems excessive. Is there an East coast distributor where I can pick up the oven and save on the shipping charges? Any other input will be appreciated.

LinkMTech
- 24th September 2014, 04:05
I tried this oven bought off eBay for a couple hundred and it didn't perform as advertised.
They state "complete heating" but it made an oval hot spot in the middle of the tray where only components in this area were soldered and the perimeter was left unsoldered. Then trying to raise the temperature to compensate only burned the boards in the center.

I liked the idea of dialing in the reflow profile once and pushing "Start" then 5 or so minutes later, ding!, done. No joy.

Decided to try a $35 Black & Decker 4-Slice Toaster oven (Model TO1313SBD) with it's claimed "Even Toasting" while requesting the return of the fancy re-flow oven. The B&D oven worked great!

Laid enough PCBs to cover the whole tray
Set the TEMP to 180 degrees C
Set function to BAKE
Set Timer pass 10 minutes then down to 5 minutes
Waited until the heating elements turned OFF indicating 180 degrees reached and started a 90 second timer.
After the 90 second pre-heat time, raised the temp to 200 degrees C for 45 to 60 seconds
At this point it was cool to watch the components quiver and flatten against the PCB as the solder melted.

Now I turned OFF the timer and carefully propped the door open a couple inches for 60 seconds
Next fully opened the door to allow the oven to cool another 60 seconds before sliding the tray out and placing on top of the oven like cooling cookies. :tongue:

It worked the same with silver bearing and regular lead solder paste.

I may have received a funky unit, don't know. But after some back and forth with the eBay dealer, they agreed to accept the return and fully refunded a$ promised.

Demon
- 24th September 2014, 17:25
...Decided to try a $35 Black & Decker 4-Slice Toaster oven (Model TO1313SBD) with it's claimed "Even Toasting" while requesting the return of the fancy re-flow oven. The B&D oven worked great!....

I had bought a nice convection oven a while back for this. Ended up giving it to my mom when her's started making fireworks so I never got into reflow.

Can you list what solder you use or any other materials?

Do you put a blob of solid solder in a corner and let it flow across the board? Are there good videos of this process?

My hands are shaking more as I get older and would love to use smaller PICs. I "might" be able to still use a SOIC (love these, nice compromise), but I wouldn't bet my house on it. I'd love to be able to use even smaller PICs.

Robert

mackrackit
- 24th September 2014, 20:31
Here are some quick and dirty instructions.
http://www.picbasic.co.uk/forum/content.php?r=105-SMD-Prototyping

LinkMTech
- 25th September 2014, 04:37
Can you list what solder you use or any other materials?


Hi Robert,
I just got into using solder stencils and bought the paste from Chipquick (http://www.chipquik.com/store/jars.htm). Using part number SMD291AX250T3 for SMT size 0805 mostly but have other larger parts on board.

PCB/Schematic capture programs:
I only have the freebie PCB programs from ExpressPCB and Pad2Pad that do not generate Gerber files or "Cream" plot but Pad2Pad can export what ever layer is selected to dxf; the board outline and pads for example.

Handling dxf files:
I have AutoSketch 9 that is a simple version of AutoCad where I take that dxf file and remove the holes then resize the SMT pads to about 80% for the solder paste and save as a new "cream" dxf file that needs to be converted to a Gerber file.

Converting dxf to Gerber:
I purchased GerbView (http://www.softwarecompanions.com/)to convert my new dxf to Gerber so the stencil manufacture can view and make for me. This was the lowest price I could find for this function.

Stencil connection:
I get my solder stencils made from Quick Stencil (http://www.quickstencil.com/default.aspx). It ships out by the next day! I started out with the kit then only had to order the stencil alone for my other projects from then on since the kit parts are the same for all.

Applying the solder paste with the solder stencil and supplied squeegee is really easy but then comes the part placement. One by one using the tweezers, have to be very careful not to bump a part while placing another is what I had to get used to.

Now pop them in the toaster oven, manually control the temperature profile and I get the manufacture solder finish! :biggrin:

mark_s
- 25th September 2014, 16:06
Louie, thanks for the info on the oven.

I have been using a $18 electric skillet from Walmart with good success. Sparkfun has a
few tutorials using the skillet method. Another useful tool for doing a few parts at a time
is the hot air rework tool found on ebay.

Robert, you need one of these and a bank loan

http://www.youtube.com/watch?v=VWi9GUzY1fY

Demon
- 25th September 2014, 18:36
Mark, I want to build my own; have everything except the controller. I came from CNC group on yahoo exactly to learn electronics for this very project.

I have 2 set of 30" stainless rods for the X and Y axis, 15" rods for Z, roller bearings, steppers, Mach 2 software. Even made my own bearing holders out of liquid plastic (Smooth-On, can even make threads in this grade of plastic).

Once here, I took the scenic root; LCDs, USB, etc. But I know I'm better prepared than ever to make one.

Just sooooo many things on TO-DO list and so few hours available in one day. The 30'x40' two storey garage also took a few years off my journey.

Louie, did you make your PCBs? If not, why not get templates at same time? Back to no gerber problem?

I use QCAD so I get everything.

Robert

LinkMTech
- 25th September 2014, 20:20
You're welcome Mark...



Louie, did you make your PCBs? If not, why not get templates at same time? Back to no gerber problem?
Robert

I get my final PCBs made through Pad2Pad because their quantity prices are good and the boards come out great too, but no way to generate the file for the stencil.
The Gerber files are available from Pad2Pad for about $25 but I would still need to generate the cream Gerber file from those so I found my own way for now.

I forgot to mention, Quick Stencil will accept CAD files (http://www.quickstencil.com/FAQ.aspx). Found out after getting the dxf to Gerber converter.

Heckler
- 26th September 2014, 14:02
Hey Robert,

Here are several good tutorials over on youtube on the eevblog channel...

https://www.youtube.com/watch?v=qyDRHI4YeMI
https://www.youtube.com/watch?v=FNNRoXZom30
https://www.youtube.com/watch?v=JA-vi2iQ5vA
https://www.youtube.com/watch?v=588iV07nEdM


hope you have a little time... this guy is great.
He is also half of the "Amp Hour" podcast duo.
dwight

Heckler
- 26th September 2014, 14:19
also check out his review of the 858d hot air reflow that you can find on amazon right now for less than $60

I have one of these (mine is labeled WEP 858D) but it's the same thing

https://www.youtube.com/watch?v=vva2t21sOAs

dwight

Demon
- 26th September 2014, 15:15
Awesome. Subscribed to this thread so I can study this.

I have a solder gun / reflow station and tweezer station; just more contraptions I was things of adding to "the machine".

Thanks.

Robert

rsocor01
- 15th November 2014, 17:49
I own the T-962A, which is bigger than the T-962. I've "cooked" thousands of boards using this reflow oven without any problems. If you use panelized boards that are too big, sometimes you get a component in the outer edges that doesn't get soldered. But, a quick eye inspection should be enough to take care of this. The reflow curve that you use to program the oven is very important. If you choose the wrong curve you can burn the board or you can get cold solder joints.

I do recommend the T-962A, but I haven't tried the T-962 model.

David Barker
- 17th November 2014, 09:55
I looked into this ages ago and it seems many people were having mixed success with the "T" range ovens. I ended up building my own. To speed things up I used off the shelf components and the results are fantastic. I wrote a little article here:

http://www.firewing.info/pmwiki.php?n=FirewingUser.BETA-Reflow-Controller

I've profiled the oven and there are very little deviations in temperature across the horizontal. This means I can easily reflow a board up to 9" x 10" (22cm x 25cm) without any hot or cold spots - all the paste reflows. Importantly, the results are reproducible and consistent. One thing I would strongly recommend is that you can monitor the profile temperature in real time. This ensures you can see how close your oven temperature matches the paste and / or component profile. The cheaper ovens allow you to set a temperature profile, but how do you know if your oven is actually doing that? Finally, I would also recommend an oven with a fan (convector) to stir up all that hot air...

Archangel
- 17th November 2014, 18:29
I looked into this ages ago and it seems many people were having mixed success with the "T" range ovens. I ended up building my own. To speed things up I used off the shelf components...
What Brand of oven did you use? Is it still available?

David Barker
- 18th November 2014, 09:29
The oven I used was this:

http://www.ecateringonline.co.uk/gastrotek-42ltr-convection-oven-unbelievable-price-1871-p.asp

Although I got mine on sale for about £150.00. It's extremely well made, all stainless steel and well insulated. Nice and big too. A lot of money, but my aim was to build a "batch" oven of high standard that could do large or multiple PCBs at one time, rather than a toaster reflow - there are tons of those on the internet, I wanted to do something a little different. For example, something like this:

http://www.blundell.co.uk/product/ha-06-batch-reflow-oven/

will cost you about £3,000 GBP (about $5,000) but mine was a fraction of this. It uses a rear mounted heating element which I removed, but kept the huge fan - I mounted two additional heating elements at the top and bottom

http://shop.electrolux.co.uk/product/3970127019/1650+Watt+Oven+Upper+Heating+Element

which fits perfectly, giving a power about of about 3.3kW (the professional batch oven above is rated at 3.6kW, so not far off)