Mimeo Apple-1 solder mask normal?

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Mimeo Apple-1 solder mask normal?

I recently purchased a new Mimeo PCB and have noticed that the solder mask seems to have a brushed effect which is actually much more noticeable in real life than in the photos I've attached.

The PCB substrate also looks much lighter than most other PCB's I've purchased in the past so not sure if this is closer to original Apple-1 as I've never actually seen one in real life only in photos. I've tried searching for other images of Mimeo boards and the substrate seems darker. Not sure if this is a recent change?

Also the the edge connector contacts look like they are sanded, not sure if this is normal as well?

I would like to make sure this is all normal before I start soldering components on.

I am slightly color blind so guess that doesn't help!

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Sorry just saw this.  I didn

Sorry just saw this.  I didn’t realize from your email what your concern really was.  

 

This is normal and and I had to pay a lot extra to have the board produced on this white Mil-spec material.   It is closer to the base color of the Apple-1 when new but thicker since there is a lot of flex in the Apple-1 board and you could crack one putting in an ACI, however after 40 years the PCB material on the real ones have greyed a little from pollution and it’s something that you could artistically recreate.   FYI.  I had an original Apple-1 come in for repair that had a sticker put on in the early 80’s that protected part of the PCB and when we removed the sticker we were able to see the whiter color as compared to  another area of the PCB material.   Also be aware the thinner original Apple-1  has a PCB that also may allow more ambient light though and be more affected by the color of the mateial underneath.   I have some photos where this is really apparent with light behind the board   

 

Cheers,

Corey

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Thanks for your reply.

Thanks for your reply.

 

I actually ordered the PCB after seeing your post here: http://www.vcfed.org/forum/showthread.php?55405-New-Apple-1-Mimeo-boards-available. It looks like this was before you changed to white material?

 

Also it seems like the white material is making the green solder mask appear much lighter shade is that correct? 

 

I didn't realize the orginal Apple-1 color had changed so drastically over the years. Do you know if there are any good quality photos available of the original Apple-1 showing white material and light shade of green? And how are you supposed to artistically recreate the color it should be today? 

 

My concern was also the solder mask. As said it looks like brushed effect so varying shades (it's difficult to see in the photo). I've never seen this before and thought it was supposed to be a uniform color?

 

Does 2518 on lower rear right corner represent the week/year when the board was manufactured?

 

I actually purchased another Apple-1 clone PCB on eBay and it looks quite a lot darker, shown in photos below.

 

I would like to build an accurate clone if possible so would appreciate others thoughts on this:)

 

 

 

 

 

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I bought one as well ...

I bought one as well thinking it would be a more accurate board than the ones Mike Willegal sold, but they are indeed too white and don't pass the "10 foot" visual test IMHO.  Sorry Corey ...  No respect lost.  I'll be building mine with gold Augats and big orange caps.  Somethng a little different ... like the board.

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If you want to see the

If you want to see the original colour of the PCB closer to 1976, on my website under the supermimeo link you can see the edge fingers of an original that was protected from pollution and the white PCB mimeo, it is closer to what it was.   

Real
IMAGE(http://myapplecomputer.net/img/orig_apple_fingers.png)

Mimeo
IMAGE(http://myapplecomputer.net/img/Mimeo_fingers_side.png)

The PCB substrate and the mask color will never match a real one as the technique for creating the Apple-1 PCBs is not only obsolete, the people who could actually do this kind of work are generally dead. PCB production back in the 70's was an art with a lot of manual work that required skills. This produces variations in the boards as well. You really should look at a mimeo and a few real ones under a microscope. FYI: I also own a Newton and even found an Obtronix, being a collector I own multiple replicas, I don't care who makes them.

The gold fingers on the newer Mimeo are brushed as well as that is part of how the gold is applied using todays technologies to meet military spec. They really need to make sure the metal is clean for modern plating machines. Modern boards are not plated with the same amount of gold as boards in the past (sorry gold reclaimers). The Mimeo boards are not lower quality boards made to maximize profits, but made in a factory that produces boards for the military prototypes and the aerospace industry. I really don't make anything on them since I do this more as a curtesy to the hobby.

If the PCB is too "white" or "clean" for you on the Mimeo, you can "wash" the board when you are done assembling using a hobby wash for models and trains. It's like a glaze you brush on that is translucent. I suggest a grey or black to "dirty" up the board, this is an old model rail road trick. Maybe Mike Willegal will chime in here, he is also a big model train hobbyist and is more familiar with the brands and how this is done on models. Most Apple-1 pictures you see are of aged or dirty boards. I would do this effect after the board is built since you don't want to wash it off after the fact. The yellow PCB materials from the earlier Mimeo's were thinner and in some lighting the green coat tinted the board to a very weird color that you couldn't make look right with artificial aging. I tried. Though they did look "old" OOTB. The Newton colors are really off, even with his white PCB material. I think I have pictures of this somewhere which I took under controlled lighting.

I can try to post pictures of boards that have been "aged" when I get back and recover from VCF West this weekend. Hopefully with so many Apple-1 at VCF West, I may be able to get a picture of a clean vs dirty early Apple-1. It's much more pronounced on the earlier boards than the NTI which are made out of a completely different material and have a different color and texture. I have a trinocular microscope, but don't have a camera yet since I usually don't need it, one day I may take some very detailed pictures.

Cheers,
Corey

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Thanks for info.

Thanks for info. Will be great to see some photos from VCF!

 

The other clone I compared it to actually came from Russia so not sure who originally designed it. It actually arrived bent so will try get it sent back. I was looking for a Newton PCB as well to compare, but they are sold out and not sure if any more are being made. 

 

I don't want to start the build and then not be satisfied with the PCB!

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Well take a look at the

Well take a look at the traces on the Russian board vs the Mimeo vs my picture of the original above.  I think you will be much more satisifed building a mimeo and aging it.  The russian board in your pics looks like it was layed out by a modern computer and pr0duced by a modern asian fab house.  Mike Willegal spend a lot of time with access to some non public and public pictures shaping the curves in the traces so they don't look like a modern layout.   This is something also not done on the Newton that is super apparient when you put one next to the real thing.  The traces are too "digital", it's very apparent in a black and white picture where you aren't distracted by color differences.  I also should mention Mike Willegal even hand created the font for the silk screen.  Pretty amazing.  It was a labor of love for him and nothing he ever really wanted to make money at. 

 

Where did you buy the Russian one, I have to have one of those now... did I not say I'm a collector ;-)  I think you said eBay, can you post a link?

 

Cheers,

Corey

 

 

 

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https://www.ebay.com/itm
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FYI, I just ordered a small

FYI, I just ordered a small batch of non-NTI and put up for sale. This time, I asked the fab to slightly age the material before production to make it look vintage or old.

 

https://www.ebay.com/itm/264509205340

 

 

 

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