Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


Heller Oven blowing parts off reflowing

Views: 3127

james

#41566

Heller Oven blowing parts off reflowing | 16 May, 2006

I know this is an old one, but we still have problems on our heller oven with parts blowing off their pads. Our other oven does not do this and it is a conceptronics oven. We do not currently have the adjustable fan speed on our heller oven. My question is do we need to have it to stop the problem.

Thanks

reply »

Chunks

#41567

Heller Oven blowing parts off reflowing | 16 May, 2006

Not knowing your brand of Heller, I might suggest disconnecting the first cooling section to verify it's your heater fans.

I just had a retro kit done to my Electrovert for a similar thing.

reply »


RDR

#41576

Heller Oven blowing parts off reflowing | 16 May, 2006

A heller that the fans work on? Wow, you should be feeling lucky!

If you are sure it the fans you should slow 'em down a bit.

Russ

reply »

james

#41583

Heller Oven blowing parts off reflowing | 17 May, 2006

We do not have a fan controller. For some reason our engineer forgot to get that added in the options. We have an 1809EXL model with not fan controller. Heller wants to charge us for that option.

reply »

#41585

Heller Oven blowing parts off reflowing | 17 May, 2006

Hello james I have been useing A heller 1809exl with the blower controls I have had some parts blowing off and adjusting the blowers to low did work for use just so you know that if you do get the option it has worked for use Good luck

reply »

james

#41588

Heller Oven blowing parts off reflowing | 17 May, 2006

Did you have to get the controller as an option?

reply »


RDR

#41590

Heller Oven blowing parts off reflowing | 17 May, 2006

I would think that you could just add a pot or something to adjust current to fans for pretty cheap

Russ

P.S. sorry about the fan joke!, had a "good experience" with them once.

reply »

marc

#41623

Heller Oven blowing parts off reflowing | 18 May, 2006

Hi James

Short answer... yes...

long answer...impingement velocity is excellent for heat transfer but it also is a higher risk of moving components. Variable speed blowers allow you to reduce the speed / impingment and more than likly your component movement issue will go away... there is a risk though. Lower converction / impingment will alter your profile, higher heater setpoints will be required to achieve the same results, make sure you profile.... often. You could get the kit from Heller which would then be the supplier solution or a home developed solutoion but this may cause issues if not done properly and would not be tied into the machine controls (software?), make sure you operators do not forget to have the proper blower speed set for the recipe. I prefer software controlled convection.

Couple other things you may want to check / verify...

- Is your placement machine properly placing? is it just dropping the component on the paste or are you properly "setting" it in the paste, fine line here. I am by no means a placement expert so I bow down to others. - Is your reflow conveyor smooth in operation, no vibrations, etc.. - rails to tight? does it bow the board up or down during the process?

Hope this helps, good luck. thanks marc

reply »

#41642

Heller Oven blowing parts off reflowing | 18 May, 2006

Hi There, I used to have a similar problem with all of our new heller ovens. I converted them with fan blower controller kit. It is really easy to do or you can have done. Its about $900/oven. For now if you do not feel like investing any money , go to your local hardware store and pick up some kitchen exhaust fan screens. Place these screens on top the rails making sure screen do not come in contact with PCB. Good luck. Keep us posted.

reply »

Chunks

#41670

Heller Oven blowing parts off reflowing | 18 May, 2006

Who says this forum is worthless? Great thread guys.

reply »

Comprehensive Analytical Services and Support

Reflow Oven