Part # for the Macintosh IIci motherboard screw

[schmosef]

Hi All,

I'm wondering if anyone knows the part number or if there's a place to order the screw used in the IIci to secure the drive cage?

I know it's not entirely necessary and is commonly lost.

I have a few IIci models in various configs and some are missing the screw. It would be nice to have for completeness sake.

 

[shirsch]

I believe it's a metric thread. Try Fastenal or McMaster-Carr.

 

[Boctor]

I believe it's a metric thread.

A backup from the old Apple site seems to confirm. I'm likely getting a IIcx chassis for a project, soon, and can check if the screw is present in there.

 

[dougg3]

The screw is Apple part number 416-1412 according to the service manual:



Looking in the Apple Service Programs Manual on Archive.org, it's identified as "Screw, M3.5x.6x8":



I just pulled one out of one of my IIcis and measured it. I would agree it's a M3.5 screw with 0.6 mm thread pitch. It's definitely longer than 8 mm though:






So I would say it's an M3.5 pan head Phillips machine screw, standard 0.6 mm thread pitch, 14 mm length. I would wager a guess that anything between 8 mm and 14 mm for length would work fine based on their service part being shorter and also how many times I have to turn the screwdriver in order to fully seat the 14 mm screw.

Edit: Checked my other IIci, it's the exact same 14 mm screw.

 

[schmosef]

Thanks, I should be able to find something off those specs.

 

[schmosef]

I ordered some 8mm and 12mm screws from here.

 

[Callan]

This looks like a match too (us based supplier - McMaster Carr) if anyone else is looking for some.

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

 

[schmosef]

Nice.

 

[schmosef]

For anyone looking at this in the future, the 8mm screws I bought ended up being too short.

The 12mm screws I bought worked fine.

 

[dougg3]

Good to know, thanks! I guess Apple’s part guide was just plain wrong on that one.

 

[zigzagjoe]

I ended up 3D printing one.

Print in ABS. 100% infill, 4 wall loops. Split in two pieces and printed in this orientation for strength. Then use acetone to fuse it together, allow to dry. OD should be 3.2mm on the shaft prior to cutting threads. Carefully thread into the case heatsert, backing out fully every few turns and cleaning the new threads.

I'll order the correct one at some point, but as an interim fix this works just fine.

 

[dschnur]

Life time supply: https://www.amazon.com/MECCANIXITY-...ctronic/dp/B0FMWKTLT2?crid=2SVVHRHT9FOV9&th=1. (Silver, not gold tinted, but you can passivate the metal and get a good color match if it matters)

(Disclaimer, I have not bought these, but they match specs. It is Amazon after all, so there is an element of risk that they will be made of recycled DDT)