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Amplifier face plate: Blue filter paper/ meter question!

william13

william13

That's not me
Tonight I am replacing a face plate on the MC300.

I received the new faceplate from Mcintosh but did not realize that it is essentially pure glass and it does not have on the inside the extra plate of glass that sandwiches in the blue filter paper. The old face plate has these and they appear intact except for the adhesive around them which I imagine stops light leakage.

So here are my questions

1. What is the safest way to peel off the inside glass plate overlying the meter window
2. Can the blue filter paper be rescued and reused?
3. What can I use for a substitute for the adhesive that prevented light leak?

Bill
 
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My MC2205 had two face adhesive foam on it. Lucky me, it'd pretty much turned to dust and fell right off. I imagine if your's doesn't want to let loose, you could just slice it in easy passes using an x-acto blade, long as you take it careful and slow. Long as the filter isn't discolored, you should be able to reuse that.

-0063-X202-A.jpg

You'll f'up the paint on the old faceplate doing it, but who cares? I imagine it's already toast if you're replacing it.

If you do need to replace the filter, the gel sheets are available here ...

Lee Filters Sheets - 118 Light Blue
$6 (20"x24")

http://www.filmtools.com/31-lee-s118.html

AND

http://www.filmtools.com/31-lee-s117.html

You need to stack both to get the exact shade for the original Mac Blue. That'll also leave you with enough filter material to do another hunnerd or so units if you've a mind to. <G>
 
sKiZo said:
My MC2205 had two face adhesive foam on it. Lucky me, it'd pretty much turned to dust and fell right off. I imagine if your's doesn't want to let loose, you could just slice it in easy passes using an x-acto blade, long as you take it careful and slow. Long as the filter isn't discolored, you should be able to reuse that.


Thank you for replying: I was beginning to think I was the only one having issues with these plates and filters. I was able to get this inside window off and the blue looks great but the inside small window has a thin black adhesive all around it. I will send pictues after work tonight. It might be hard removing this.
-0063-X202-A.jpg

You'll f'up the paint on the old faceplate doing it, but who cares? I imagine it's already toast if you're replacing it.

If you do need to replace the filter, the gel sheets are available here ...

Lee Filters Sheets - 118 Light Blue
$6 (20"x24")

http://www.filmtools.com/31-lee-s118.html

AND

http://www.filmtools.com/31-lee-s117.html

You need to stack both to get the exact shade for the original Mac Blue. That'll also leave you with enough filter material to do another hunnerd or so units if you've a mind to. <G>
Click to expand...
 
The blue material attached to the glass on earlier models was plexiglass, the gels went into the meters. Never had to replace the glass on a MC300 yet, so you are saying the material attached to the glass is a thin gel?
 
c_dk said:
The blue material attached to the glass on earlier models was plexiglass, the gels went into the meters. Never had to replace the glass on a MC300 yet, so you are saying the material attached to the glass is a thin gel?
Click to expand...

I was able to easily pry one of the inside glass pieces off the "window" that goes in front of the meter. That glass or probably plexiglass is tinted blue. This was adhered to the inside glass of the faceplate with an adhesive that was contained just inside the boundaries of the plexiglass. The adhesive came off with the plexiglass and is firmly attached and could be an issue unless I can "repeal and replace" (excuse the pun and hopefully did not offend anyone with political remark)
I can send picture latter.
 
william13 said:
I was able to easily pry one of the inside glass pieces off the "window" that goes in front of the meter. That glass or probably plexiglass is tinted blue. This was adhered to the inside glass of the faceplate with an adhesive that was contained just inside the boundaries of the plexiglass. The adhesive came off with the plexiglass and is firmly attached and could be an issue unless I can "repeal and replace" (excuse the pun and hopefully did not offend anyone with political remark)
I can send picture latter.
Click to expand...
IMG_5425.JPG
 
I am making progress getting this double faced foam adhesive strip off. (soaked in wd 40 for 2 hours and then very careful scrapping with a scalpel). Overlying this blue plexiglass plate (around the edges is a tape) But I do not know if this was just plain tape 30 years ago or if this was tape with foam to keep the light contained. Hard to find old pictures in terms of what lies behind the glass on these old amps.
 
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I have used sealer putty - the type that comes in strips to reattach the plexiglass filters to the faceplate. So far no problems with the putty that is less messy and easier to work with, IMO.

Might also be worth converting to LED illumination while you're in there.
 
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62caddy said:
I have used sealer putty - the type that comes in strips to reattach the plexiglass filters to the faceplate. So far no problems with the putty that is less messy and easier to work with, IMO.

Might also be worth converting to LED illumination while you're in there.
Click to expand...

That's a thought...Whats the difference with the lights? I will research sealer putty. Thanks! Bill
 
william13 said:
That's a thought...Whats the difference with the lights? I will research sealer putty. Thanks! Bill
Click to expand...

LEDs: Cooler operation, usually brighter and will probably never need to be replaced again. I see they must be soldered in on the MC300 unfortunately.

Check eBay listing for "McIntosh MC300 LED" - they should come right up. Just checked myself.
 
I will check into the LED. upgrade. Soldering is not an issue.
Happy to say that I found the best way to remove adhesive from the blue plexiglass is WD 40 along with an old plastic credit card.
The diffuser attaches to the back of the faceplate with adhesive but must be surgically and perfectly aligned so as to also fit over 4 lights.
I have not attached it to the faceplate yet for concern of misalignment. I am thinking the best way to handle this is to place the diffuser over the 4 lights and put some adhesive on it and then apply the faceplate and push.
 
So laying a diffuser down perfectly on the faceplate is daunting. A slight upward or downward or left or right movement will mess it up. I did several dry runs to see if I could just lay it down and it was a 50/50 thing. Once one uses the adhesive you do not get another chance as I heard it will remove paint. So I developed an alternate method. I laid the diffuser on the faceplate and moved it into perfect position. Then I put a piece of foam board behind it and taped the two together to form a hinge type mechanism. Then I secured the board to the faceplate with painters tape. Now I can open and close the diffuser like a door and each time it falls perfectly on the emblems. Today I will put double sided tape on the diffuser and close the door and pray
 
Late to the party again, but I’m looking into doing this as well.
WITH EXTREME CAUTION. But as we read here, I think Bill did
such a good job that I’ll bet he could’ve done an even better job
repainting the original glass himself!

I just know when I get to the faceplate that most of the perimeter
black paint will flake off …
 
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