New VirEnce MCPCB for E17/E21/119/144/233U

[clemence]

@The_Driver

Screws in general might be a problem. They might create an electrical connection between mpcb and the heatsink.

No if you use high strength plastic screws

[Wieselflinkpro]

@clemence

16mm board

- 1,6 - 1,8mm thick

- 2 x 3mm dia. wire slots

• with/without thermal pad (0,5/1 mm thick)

20mm Board

- 1,6 - 1,8mm thick

- standard screw slots

- 2 x 3mm dia. wire slots

• with/without thermal pad (0,5/1 mm thick)

Thermal pad info:

- Thermal conductivity 12 W/M.K

- Thermal resistance 0,18 C/W at 50 psi

• Compressible down to 30% original thickness at 100 psi

What about optics holes? Ledil / Carclo / Gaggione / else?
Feel free to add more suggestions

Are they still under development?
When will them be sold?
What is the expected price?

[djozz]

@clemence

@The_Driver

Screws in general might be a problem. They might create an electrical connection between mpcb and the heatsink.

No if you use high strength plastic screws

and not if there is a copper trace clear-out of 2mm around the holes so the screw head can not get in contact with the electrical circuitry

[clemence]

@Wieselflinkpro

@clemence

16mm board

- 1,6 - 1,8mm thick

- 2 x 3mm dia. wire slots

• with/without thermal pad (0,5/1 mm thick)

20mm Board

- 1,6 - 1,8mm thick

- standard screw slots

- 2 x 3mm dia. wire slots

• with/without thermal pad (0,5/1 mm thick)

Thermal pad info:

- Thermal conductivity 12 W/M.K

- Thermal resistance 0,18 C/W at 50 psi

• Compressible down to 30% original thickness at 100 psi

What about optics holes? Ledil / Carclo / Gaggione / else?
Feel free to add more suggestions

Are they still under development?
When will them be sold?
What is the expected price?

- The (three) designs are 90% ready for upload, only holes/slots placement left. I also design another aluminum square DTP 30mm x 25mm linear 3535 single/triple config exclusively for use with LEDIL STRADA and SHELLY

- ASAP in early February. But please, please, don’t take it tightly. I’ve been trying my best to be a faster designer/provider, yet still not fast enough for BLF.

• Will TRY to bring them here at approximately USD 3 - 4/pcs

[Barkuti]

C'mon! A fiber washer is all you need for those metal screws.

Cheers ^:)

[clemence]

@Barkuti

C’mon! A fiber washer is all you need for those metal screws.

Cheers :partying_face:

No, plain washer still expose the screw thread to possibly contact to the MCPCB body
You have to at least use waisted/flanged washer to insulate both the screw head and the thread body, otherwise you’ll screw it. But flanged washer will need bigger holes. Normal clearance fit for M3 x 0,5 is 3,2mm. With flanged washer you have to open up to 3,8-4mm minimum hole diameter.
With plastic screw you can save the precious surface area and simplify installation. Plastic screw comes in wide variety of materials and designs.

[Cula]

@clemence

No, plain washer still expose the screw thread to possibly contact to the MCPCB body
You have to at least use waisted/flanged washer to insulate both the screw head and the thread body, otherwise you’ll screw it. But flanged washer will need bigger holes. Normal clearance fit for M3 x 0,5 is 3,2mm. With flanged washer you have to open up to 3,8-4mm minimum hole diameter.
With plastic screw you can save the precious surface area and simplify installation. Plastic screw comes in wide variety of materials and designs.

Hi Clemence,

Got a link for those hi strength plastic screws?

Thanks

[clemence]

@Cula

@clemence

No, plain washer still expose the screw thread to possibly contact to the MCPCB body
You have to at least use waisted/flanged washer to insulate both the screw head and the thread body, otherwise you’ll screw it. But flanged washer will need bigger holes. Normal clearance fit for M3 x 0,5 is 3,2mm. With flanged washer you have to open up to 3,8-4mm minimum hole diameter.
With plastic screw you can save the precious surface area and simplify installation. Plastic screw comes in wide variety of materials and designs.

Hi Clemence,

Got a link for those hi strength plastic screws?

Thanks

http://www.extreme-bolt.com/applications-high-temperature.html
https://www.plasticnutsandbolts.com/materialsz.html
https://solidspot.com/engineering_plastic_screws.html

PEEK is my preferred material choice

[clemence]

Please review these drafts.

Decided to follow standard “star” shape, though mine is rounded to make centering easier if necessary.
I still haven’t heard about optic holes for the 20mm. Should I just leave it blank? So everyone can just drill themselves?
I prefer to leave it blank, since in this CDTP design, anode/cathode surface area is of high importance.

@Barkuti: Dude, you get those slots.

Thank you,

• Clemence

[djozz]

So the +trace is one large pour over the entire surface with just a clearing for the -pad which is a small connection the size of the solder pad going down to the core?

(I’m not familiar with single led optics so I can’t advice on the holes)

[clemence]

@djozz

So the +trace is one large pour over the entire surface with just a clearing for the -pad which is a small connection the size of the solder pad going down to the core?

(I’m not familiar with single led optics so I can’t advice on the holes)

That, I can’t tell you yet

[clemence]

@chouster

Well, I think the opposite is the case. That stuff is for special applications. For normal application, just go with normal solder paste. Or go with SnAg (96.5/3.5) if you really want good thermal properties. 221°C reflow temperature shouldn’t be a problem at all and that stuff is quite affordable.

Ever wondering why this budget friendly Sn96,5Ag3,5 with superior thermal conductivity 78 W/M.K is not so popular?
Here’s the answer: http://www.psma.com/ul_files/forums/leadfree/aim_lead_free_guide.pdf
The short answer is it has somewhat troublesome wetting ability. Not a good thing for automated soldering. But for us who really likes to spend hours just to get perfect reflow, this should not be a major problem. The jump from ~50 W/M.K to 78 W/M.K is indeed worth the hassles.

- Clemence

[clemence]

Eye candy

[djozz]

Nice render, time for and avatar picture change?

[clemence]

Ah, Forgot that. Thanks Jos

[clemence]

The PEEK screw and 12 W/M.K thermal pad samples are on their way to my workshop……
Will be a great chrismast gift!

- Clemence

[The_Driver1 (The_Driver)]

Any updates on the PCBs and screws?

[clemence]

@The_Driver

Any updates on the PCBs and screws?

The screw samples are still on holiday trip to my country. Just received the expensive thermal pad samples this afternoon.
12 W/M.K 0,5mm thick, not bad eh?

[djozz]

0.5mm thick copper tracing??

[clemence]

@djozz

0.5mm thick copper tracing??

OMD, I wish…
No, it’s the thermal pads to insulate the MCPCB from the base