Heat sink lock in retaining spring...

[Sylvia Else]

Anyone had the misfortune to encounter these?

https://www.tme.eu/en/details/thfu-3/heatsinks-equipment/fischer-elektronik/thfu-3/

I bought some for use with the appropriate heat sinks some years ago.
While I did eventually manage to fit them, doing so seemed to require
simultaneous dexterity and strength. There seemed considerable scope for
destroying the (quiet expensive, in my case) devices to be cooled.

Perhaps there\'s a special tool (at a special tool type price), but I
have not found mention of one. Somehow I don\'t see assembly-line workers
achieving smooth progress with these.

Sylvia.

 

[Ricky]

On Friday, July 14, 2023 at 1:34:52 AM UTC-4, Sylvia Else wrote:

Anyone had the misfortune to encounter these?

https://www.tme.eu/en/details/thfu-3/heatsinks-equipment/fischer-elektronik/thfu-3/

I bought some for use with the appropriate heat sinks some years ago.
While I did eventually manage to fit them, doing so seemed to require
simultaneous dexterity and strength. There seemed considerable scope for
destroying the (quiet expensive, in my case) devices to be cooled.

Perhaps there\'s a special tool (at a special tool type price), but I
have not found mention of one. Somehow I don\'t see assembly-line workers
achieving smooth progress with these.

I don\'t know anything about these clips, but it\'s not uncommon for heat sinks to be rather hard to attach. They want to keep it as low cost as possible, while keeping pressure on the heat sink for a good fit. Ease of use seems to be secondary. The factory knows how to make it all work.

An image of heat sink might help. Is there a bracket that bolts to the mother board?

--

Rick C.

- Get 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209

 

[Jeff Layman]

On 14/07/2023 06:34, Sylvia Else wrote:

Anyone had the misfortune to encounter these?

https://www.tme.eu/en/details/thfu-3/heatsinks-equipment/fischer-elektronik/thfu-3/

I bought some for use with the appropriate heat sinks some years ago.
While I did eventually manage to fit them, doing so seemed to require
simultaneous dexterity and strength. There seemed considerable scope for
destroying the (quiet expensive, in my case) devices to be cooled.

Perhaps there\'s a special tool (at a special tool type price), but I
have not found mention of one. Somehow I don\'t see assembly-line workers
achieving smooth progress with these.

They look somewhat similar to SS clips used to hold glass onto
metal-framed greenhouses here in the UK. They require considerable force
to put in place with the added hazard of trying to avoid breaking the glass!
<https://www.amazon.co.uk/Band-Clips-Greenhouse-Glass-Pack/dp/B00E7VRG6O>

--

Jeff

 

[Sylvia Else]

On 14-July-23 4:55 pm, Ricky wrote:

On Friday, July 14, 2023 at 1:34:52 AM UTC-4, Sylvia Else wrote:
Anyone had the misfortune to encounter these?

https://www.tme.eu/en/details/thfu-3/heatsinks-equipment/fischer-elektronik/thfu-3/

I bought some for use with the appropriate heat sinks some years ago.
While I did eventually manage to fit them, doing so seemed to require
simultaneous dexterity and strength. There seemed considerable scope for
destroying the (quiet expensive, in my case) devices to be cooled.

Perhaps there\'s a special tool (at a special tool type price), but I
have not found mention of one. Somehow I don\'t see assembly-line workers
achieving smooth progress with these.

I don\'t know anything about these clips, but it\'s not uncommon for heat sinks to be rather hard to attach. They want to keep it as low cost as possible, while keeping pressure on the heat sink for a good fit. Ease of use seems to be secondary. The factory knows how to make it all work.

An image of heat sink might help. Is there a bracket that bolts to the mother board?

https://au.rs-online.com/web/p/heatsinks/7226915

The heat sink has a grooved slot at the base into which one can tap one
or more M3 bolts. The heat sink is made of aluminium of course, so
tapping the bolt works well enough.

As I check through my records, I find that the devices at risk were
nothing like as expensive as I\'d thought. Still removing a 5 lead device
and replacing it is a tiresome exercise.

In future I\'ll stick with heat sinks that accept a bolt through the
(TO220-5) device.

Sylvia.

 

[Fred Bloggs]

On Friday, July 14, 2023 at 1:34:52 AM UTC-4, Sylvia Else wrote:

Anyone had the misfortune to encounter these?

https://www.tme.eu/en/details/thfu-3/heatsinks-equipment/fischer-elektronik/thfu-3/

I bought some for use with the appropriate heat sinks some years ago.
While I did eventually manage to fit them, doing so seemed to require
simultaneous dexterity and strength. There seemed considerable scope for
destroying the (quiet expensive, in my case) devices to be cooled.

Perhaps there\'s a special tool (at a special tool type price), but I
have not found mention of one. Somehow I don\'t see assembly-line workers
achieving smooth progress with these.

You\'re using the wrong heatsink for the clip, or more precisely, the wrong clip for the heatsink. This couldn\'t be simpler.

https://www.farnell.com/datasheets/1332110.pdf

Sylvia.

 

[Sylvia Else]

On 14-July-23 11:56 pm, Fred Bloggs wrote:

On Friday, July 14, 2023 at 1:34:52 AM UTC-4, Sylvia Else wrote:
Anyone had the misfortune to encounter these?

https://www.tme.eu/en/details/thfu-3/heatsinks-equipment/fischer-elektronik/thfu-3/

I bought some for use with the appropriate heat sinks some years ago.
While I did eventually manage to fit them, doing so seemed to require
simultaneous dexterity and strength. There seemed considerable scope for
destroying the (quiet expensive, in my case) devices to be cooled.

Perhaps there\'s a special tool (at a special tool type price), but I
have not found mention of one. Somehow I don\'t see assembly-line workers
achieving smooth progress with these.

You\'re using the wrong heatsink for the clip, or more precisely, the wrong clip for the heatsink. This couldn\'t be simpler.

https://www.farnell.com/datasheets/1332110.pdf


Sylvia.

I\'m actually using

https://au.rs-online.com/web/p/heatsink-mounting-accessories/7226921

60 Newtons is quite a lot of force to be applying by hand to the end of
the clip, while at the same time trying not apply any force to the
device until the clip is in the correct position.

While that force is being applied to allow the clip to pass in front of
the device, the friction at the pivot point is much increased, making it
difficult to slide the clip sideways.

Sylvia.

 

[John Larkin]

On Fri, 14 Jul 2023 19:34:42 +1000, Sylvia Else <sylvia@email.invalid>
wrote:

On 14-July-23 4:55 pm, Ricky wrote:
On Friday, July 14, 2023 at 1:34:52?AM UTC-4, Sylvia Else wrote:
Anyone had the misfortune to encounter these?

https://www.tme.eu/en/details/thfu-3/heatsinks-equipment/fischer-elektronik/thfu-3/

I bought some for use with the appropriate heat sinks some years ago.
While I did eventually manage to fit them, doing so seemed to require
simultaneous dexterity and strength. There seemed considerable scope for
destroying the (quiet expensive, in my case) devices to be cooled.

Perhaps there\'s a special tool (at a special tool type price), but I
have not found mention of one. Somehow I don\'t see assembly-line workers
achieving smooth progress with these.

I don\'t know anything about these clips, but it\'s not uncommon for heat sinks to be rather hard to attach. They want to keep it as low cost as possible, while keeping pressure on the heat sink for a good fit. Ease of use seems to be secondary. The factory knows how to make it all work.

An image of heat sink might help. Is there a bracket that bolts to the mother board?


https://au.rs-online.com/web/p/heatsinks/7226915

The heat sink has a grooved slot at the base into which one can tap one
or more M3 bolts. The heat sink is made of aluminium of course, so
tapping the bolt works well enough.

As I check through my records, I find that the devices at risk were
nothing like as expensive as I\'d thought. Still removing a 5 lead device
and replacing it is a tiresome exercise.

In future I\'ll stick with heat sinks that accept a bolt through the
(TO220-5) device.

Sylvia.

Some big mosfets don\'t have a mounting hole. That leaves more room for
silicon. We clip mount them, but with screws.

https://www.dropbox.com/scl/fi/9qb2eej6ww2jmj03fv261/L500_wiring.JPG?rlkey=5b2vuiviwaqwldgyrukh5hn5m&raw=1

At the 5ish watt level, we surface mount dpaks and use a surface-mount
heatsink.

 

[John Larkin]

On Fri, 14 Jul 2023 06:56:52 -0700 (PDT), Fred Bloggs
<bloggs.fredbloggs.fred@gmail.com> wrote:

On Friday, July 14, 2023 at 1:34:52?AM UTC-4, Sylvia Else wrote:
Anyone had the misfortune to encounter these?

https://www.tme.eu/en/details/thfu-3/heatsinks-equipment/fischer-elektronik/thfu-3/

I bought some for use with the appropriate heat sinks some years ago.
While I did eventually manage to fit them, doing so seemed to require
simultaneous dexterity and strength. There seemed considerable scope for
destroying the (quiet expensive, in my case) devices to be cooled.

Perhaps there\'s a special tool (at a special tool type price), but I
have not found mention of one. Somehow I don\'t see assembly-line workers
achieving smooth progress with these.

You\'re using the wrong heatsink for the clip, or more precisely, the wrong clip for the heatsink. This couldn\'t be simpler.

https://www.farnell.com/datasheets/1332110.pdf

No insulator?

 

[Fred Bloggs]

On Friday, July 14, 2023 at 11:06:59 AM UTC-4, John Larkin wrote:

On Fri, 14 Jul 2023 19:34:42 +1000, Sylvia Else <syl...@email.invalid
wrote:
On 14-July-23 4:55 pm, Ricky wrote:
On Friday, July 14, 2023 at 1:34:52?AM UTC-4, Sylvia Else wrote:
Anyone had the misfortune to encounter these?

https://www.tme.eu/en/details/thfu-3/heatsinks-equipment/fischer-elektronik/thfu-3/

I bought some for use with the appropriate heat sinks some years ago.
While I did eventually manage to fit them, doing so seemed to require
simultaneous dexterity and strength. There seemed considerable scope for
destroying the (quiet expensive, in my case) devices to be cooled.

Perhaps there\'s a special tool (at a special tool type price), but I
have not found mention of one. Somehow I don\'t see assembly-line workers
achieving smooth progress with these.

I don\'t know anything about these clips, but it\'s not uncommon for heat sinks to be rather hard to attach. They want to keep it as low cost as possible, while keeping pressure on the heat sink for a good fit. Ease of use seems to be secondary. The factory knows how to make it all work.

An image of heat sink might help. Is there a bracket that bolts to the mother board?


https://au.rs-online.com/web/p/heatsinks/7226915

The heat sink has a grooved slot at the base into which one can tap one
or more M3 bolts. The heat sink is made of aluminium of course, so
tapping the bolt works well enough.

As I check through my records, I find that the devices at risk were
nothing like as expensive as I\'d thought. Still removing a 5 lead device
and replacing it is a tiresome exercise.

In future I\'ll stick with heat sinks that accept a bolt through the
(TO220-5) device.

Sylvia.


Some big mosfets don\'t have a mounting hole. That leaves more room for
silicon. We clip mount them, but with screws.

https://www.dropbox.com/scl/fi/9qb2eej6ww2jmj03fv261/L500_wiring.JPG?rlkey=5b2vuiviwaqwldgyrukh5hn5m&raw=1

At the 5ish watt level, we surface mount dpaks and use a surface-mount
heatsink.

The clip Sylvia called out is held in place by the friction of inserting the spring steel clip end in that heat sink slot. I wouldn\'t expect it to pass a drop test. It might be okay if you can epoxy it in some way. Thermal epoxy is pricey, requires refrigeration, and has limited storage time before it \'expires\'- at least last time I used it.

 

[Jasen Betts]

On 2023-07-14, Sylvia Else <sylvia@email.invalid> wrote:

On 14-July-23 11:56 pm, Fred Bloggs wrote:
On Friday, July 14, 2023 at 1:34:52 AM UTC-4, Sylvia Else wrote:
Anyone had the misfortune to encounter these?

https://www.tme.eu/en/details/thfu-3/heatsinks-equipment/fischer-elektronik/thfu-3/

I bought some for use with the appropriate heat sinks some years ago.
While I did eventually manage to fit them, doing so seemed to require
simultaneous dexterity and strength. There seemed considerable scope for
destroying the (quiet expensive, in my case) devices to be cooled.

Perhaps there\'s a special tool (at a special tool type price), but I
have not found mention of one. Somehow I don\'t see assembly-line workers
achieving smooth progress with these.

You\'re using the wrong heatsink for the clip, or more precisely, the wrong clip for the heatsink. This couldn\'t be simpler.

https://www.farnell.com/datasheets/1332110.pdf


Sylvia.

I\'m actually using

https://au.rs-online.com/web/p/heatsink-mounting-accessories/7226921

60 Newtons is quite a lot of force to be applying by hand to the end of
the clip, while at the same time trying not apply any force to the
device until the clip is in the correct position.
While that force is being applied to allow the clip to pass in front of
the device, the friction at the pivot point is much increased, making it
difficult to slide the clip sideways.

Must the clip be loaded from the end or can it be loaded from the
face, possibly by using wide mouth pliers as a press.

--
Jasen.
🇺🇦 Слава Україні

 

[Sylvia Else]

On 18-July-23 8:53 pm, Jasen Betts wrote:

On 2023-07-14, Sylvia Else <sylvia@email.invalid> wrote:
On 14-July-23 11:56 pm, Fred Bloggs wrote:
On Friday, July 14, 2023 at 1:34:52 AM UTC-4, Sylvia Else wrote:
Anyone had the misfortune to encounter these?

https://www.tme.eu/en/details/thfu-3/heatsinks-equipment/fischer-elektronik/thfu-3/

I bought some for use with the appropriate heat sinks some years ago.
While I did eventually manage to fit them, doing so seemed to require
simultaneous dexterity and strength. There seemed considerable scope for
destroying the (quiet expensive, in my case) devices to be cooled.

Perhaps there\'s a special tool (at a special tool type price), but I
have not found mention of one. Somehow I don\'t see assembly-line workers
achieving smooth progress with these.

You\'re using the wrong heatsink for the clip, or more precisely, the wrong clip for the heatsink. This couldn\'t be simpler.

https://www.farnell.com/datasheets/1332110.pdf


Sylvia.

I\'m actually using

https://au.rs-online.com/web/p/heatsink-mounting-accessories/7226921

60 Newtons is quite a lot of force to be applying by hand to the end of
the clip, while at the same time trying not apply any force to the
device until the clip is in the correct position.
While that force is being applied to allow the clip to pass in front of
the device, the friction at the pivot point is much increased, making it
difficult to slide the clip sideways.

Must the clip be loaded from the end or can it be loaded from the
face, possibly by using wide mouth pliers as a press.

It can be placed into the slot in the face easily - no force required -
but with only about 2mm clearance between the clip and face. Significant
force is then required to pull it outwards to clear the device being cooled.

No doubt a special tool could be devised.

Sylvia.

 

[Sylvia Else]

On 15-July-23 1:12 am, John Larkin wrote:

On Fri, 14 Jul 2023 06:56:52 -0700 (PDT), Fred Bloggs
bloggs.fredbloggs.fred@gmail.com> wrote:

On Friday, July 14, 2023 at 1:34:52?AM UTC-4, Sylvia Else wrote:
Anyone had the misfortune to encounter these?

https://www.tme.eu/en/details/thfu-3/heatsinks-equipment/fischer-elektronik/thfu-3/

I bought some for use with the appropriate heat sinks some years ago.
While I did eventually manage to fit them, doing so seemed to require
simultaneous dexterity and strength. There seemed considerable scope for
destroying the (quiet expensive, in my case) devices to be cooled.

Perhaps there\'s a special tool (at a special tool type price), but I
have not found mention of one. Somehow I don\'t see assembly-line workers
achieving smooth progress with these.

You\'re using the wrong heatsink for the clip, or more precisely, the wrong clip for the heatsink. This couldn\'t be simpler.

https://www.farnell.com/datasheets/1332110.pdf


No insulator?

In this case the heat sink was isolated, and the device was an audio
frequency power amplifier. Built onto a home-etched board[*], two have
worked without incident for many years.

Sylvia

[*] I don\'t do this any more. Much too troublesome.

 

[legg]

On Fri, 14 Jul 2023 15:34:43 +1000, Sylvia Else <sylvia@email.invalid>
wrote:

Anyone had the misfortune to encounter these?

https://www.tme.eu/en/details/thfu-3/heatsinks-equipment/fischer-elektronik/thfu-3/

I bought some for use with the appropriate heat sinks some years ago.
While I did eventually manage to fit them, doing so seemed to require
simultaneous dexterity and strength. There seemed considerable scope for
destroying the (quiet expensive, in my case) devices to be cooled.

Perhaps there\'s a special tool (at a special tool type price), but I
have not found mention of one. Somehow I don\'t see assembly-line workers
achieving smooth progress with these.

Sylvia.

For insertion, an oversized pair of pincing pliers will work.

For removal, a screw driver pry. Don\'t re-use the clip.

Helps if the heatsink and clips are designed for each other, and
the right size for the package and mounting height intended.

If it\'s too difficult to get a reliable and secure mount, use
a different mounting method. This stuff is not intended for
one-off projects.

RL

RL

 

[John Larkin]

On Tue, 18 Jul 2023 22:15:41 +1000, Sylvia Else <sylvia@email.invalid>
wrote:

On 15-July-23 1:12 am, John Larkin wrote:
On Fri, 14 Jul 2023 06:56:52 -0700 (PDT), Fred Bloggs
bloggs.fredbloggs.fred@gmail.com> wrote:

On Friday, July 14, 2023 at 1:34:52?AM UTC-4, Sylvia Else wrote:
Anyone had the misfortune to encounter these?

https://www.tme.eu/en/details/thfu-3/heatsinks-equipment/fischer-elektronik/thfu-3/

I bought some for use with the appropriate heat sinks some years ago.
While I did eventually manage to fit them, doing so seemed to require
simultaneous dexterity and strength. There seemed considerable scope for
destroying the (quiet expensive, in my case) devices to be cooled.

Perhaps there\'s a special tool (at a special tool type price), but I
have not found mention of one. Somehow I don\'t see assembly-line workers
achieving smooth progress with these.

You\'re using the wrong heatsink for the clip, or more precisely, the wrong clip for the heatsink. This couldn\'t be simpler.

https://www.farnell.com/datasheets/1332110.pdf


No insulator?


In this case the heat sink was isolated, and the device was an audio
frequency power amplifier. Built onto a home-etched board[*], two have
worked without incident for many years.

Sylvia

[*] I don\'t do this any more. Much too troublesome.

Eventually one gets tired of the hassle and mess, especially with
ferric chloride under ones fingernails.

Multilayer, plated-thru, solder masked, silkscreened boards are cheap
now, thank Goodness.

 

[John Larkin]

On Tue, 18 Jul 2023 10:38:06 -0400, legg <legg@nospam.magma.ca> wrote:

On Fri, 14 Jul 2023 15:34:43 +1000, Sylvia Else <sylvia@email.invalid
wrote:

Anyone had the misfortune to encounter these?

https://www.tme.eu/en/details/thfu-3/heatsinks-equipment/fischer-elektronik/thfu-3/

I bought some for use with the appropriate heat sinks some years ago.
While I did eventually manage to fit them, doing so seemed to require
simultaneous dexterity and strength. There seemed considerable scope for
destroying the (quiet expensive, in my case) devices to be cooled.

Perhaps there\'s a special tool (at a special tool type price), but I
have not found mention of one. Somehow I don\'t see assembly-line workers
achieving smooth progress with these.

Sylvia.


For insertion, an oversized pair of pincing pliers will work.

For removal, a screw driver pry. Don\'t re-use the clip.

Helps if the heatsink and clips are designed for each other, and
the right size for the package and mounting height intended.

If it\'s too difficult to get a reliable and secure mount, use
a different mounting method. This stuff is not intended for
one-off projects.

RL

RL

There is an instant-set (modestly) thermally conductive Locktite.

I like surface-mount fets with surface-mount heat sinks.

Standing up, just bolt a TO220 or TO247 to an isolated heat sink.

https://www.dropbox.com/s/mi8ijm3oqqpbf9q/P902B_3.jpg?raw=1