Maker Pro
Maker Pro

Melted Connector

M

Mark Kelepouris

Jan 1, 1970
0
TTman said:
That must have been really ,really cheap...... You sure it's 265 ?? what
about the pre-heat?

My only explanation for this kind of thing happening, would be that (it's
possible!) a pack of Crayons fell into the plastic mixture at the Chinese
manufacturing plant. ;)

Mark Kelepouris
 
T

TTman

Jan 1, 1970
0
Here is what happens when you try and reflow cheap OneHungLow brand header
connectors:http://www.alternatezone.com/images/MeltedConnector.JPG
Temperature profile peak was only 265 degC.

Dave.

Regardless of the temperature, I would put jumper blocks on them first
and discard them later. The jumper blocks should hold it in place and
shield the metal, which draw heat faster than plastic.

I never have to do that,and I use both single and dual pin strip
headers..... Lead free, flow soldered, 267 C , preheat 45 seconds @ 330C
over
hotplate, 1.2 M/sec
 
E

Eeyore

Jan 1, 1970
0
David L. Jones said:
Here is what happens when you try and reflow cheap OneHungLow brand header
connectors:

Who does your purchasing or sub-contracting ? OneHungLow indeed !

Graham
 
L

L.A.T.

Jan 1, 1970
0
Eeyore said:
Who does your purchasing or sub-contracting ? OneHungLow indeed !

Graham
Most of these components come from The Bung Thing Manufacturing Company.
 
Regardless of the temperature, I would put jumper blocks on them first
and discard them later.  The jumper blocks should hold it in place and
shield the metal, which draw heat faster than plastic.

not much point in machine assembly if you have to manually put on
jumper blocks
and such ....
I never have to do that,and I use both single and dual pin strip
headers..... Lead free, flow soldered, 267 C , preheat 45 seconds @ 330C
over
hotplate, 1.2 M/sec

-Lasse
 
D

David L. Jones

Jan 1, 1970
0
linnix said:
Regardless of the temperature, I would put jumper blocks on them first
and discard them later. The jumper blocks should hold it in place and
shield the metal, which draw heat faster than plastic.

No need to do that for every other brand on the market, they survive quite
nicely just like they are designed to do.

Dave.
 
D

David L. Jones

Jan 1, 1970
0
TTman said:
That must have been really ,really cheap...... You sure it's 265 ?? what
about the pre-heat?

Yep, that figure comes direct form the board loader who were monitoring the
temp as part of an initial pre-production run, it includes pre-heat.

Dave.
 
D

David L. Jones

Jan 1, 1970
0
Mark Kelepouris said:
My only explanation for this kind of thing happening, would be that (it's
possible!) a pack of Crayons fell into the plastic mixture at the Chinese
manufacturing plant. ;)

I think you are right on the money!

Dave.
 
D

David L. Jones

Jan 1, 1970
0
Eeyore said:
Who does your purchasing or sub-contracting ? OneHungLow indeed !

Mostly in-house purchasing, but I don't know who's responsible for this one.
We usually use Samtec headers.

Dave.
 
E

Eeyore

Jan 1, 1970
0
David L. Jones said:
Mostly in-house purchasing, but I don't know who's responsible for this one.
We usually use Samtec headers.

Never had a problem with Samtec for sure. Sometimes engineers have to fight a
battle with purchasing. I foresaw a problem with a particular component on a
£750,000 contract some 20 years ago and pressurised purchasing in the presence
of board members to give extra lead time for these, since we hadn't ordered that
specific model in ages.

Did they ? Hell no ! It resulted in the ONE problem with project completion,
dealines and in-field reliability.

Graham
 
R

Rich Grise

Jan 1, 1970
0
Never had a problem with Samtec for sure. Sometimes engineers have to
fight a battle with purchasing. I foresaw a problem with a particular
component on a £750,000 contract some 20 years ago and pressurised
purchasing in the presence of board members to give extra lead time for
these, since we hadn't ordered that specific model in ages.

Did they ? Hell no ! It resulted in the ONE problem with project
completion, dealines and in-field reliability.

Many years ago, I worked for a plastics extruder, who got a contract to
make the plastic things that the customer then stuffed with pins. They
searched for WEEKS to find a plastic that could be extruded for less than
a king's ransom, yet still meet fire specs. The term 94V0 springs to mind,
but I couldn't swear to it. The plastic wasn't glass-filled - it was some
variety of vinyl, IIRC, but nothing was ever said about melting in service;
it was extruded at about 450 F, at which temp. it was still quite stiff.

The customer was happy with the result, but these were through-hole
headers, if that has anything to do with it.

Cheers!
Rich
 
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