ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Well....I didn't win any prizes in the draw, but I did get this in the post today....the Kilopoise grease, I just hope the police don't call.....I'm sure to be arrested!
Removed the secondary operating panel lid and glass plate, will clean the linear sliders...
Now I can access the lid damper....as can be seen it has been bleeding over the internals of the machine foe a while.....
Lifted him out for a closer inspection......
The operation of the damper feels quite stiff when rotated, however I have no means of comparison for this, but I'm not seeing a way inside to replace the kilopoise grease.....curiously the locating/fixing lugs located around the circumference of the damper appear to have been melted/fused together with a soldering iron....is this factory practice or an attempt to fasten it together tighter and prevent leakage?
either way opening this up may lead to terminal damage...….any advice (Martin, I'm looking at you )
This post I made last year shows what they look like taken apart. They are often heat fused shut so you have to break the seal.
-sonavor
Here is another post on the dampers.-sonavor
Drill a small hole, inject grease while rotating the damper spindle, melt or glue the hole shut?
Martin
Thats quite a cracking bit of lateral thinking!
I'll try and drill a hole in what will be the top of the drum when it's in it's normal position to help reduce the possibility of leaking through the sealed up hole.
Craig
Ok.….here we go, bored a 2mm hole in the side of the damper drum carefully so as not to damage the internal turbine blades.
Managed to pump a reasonable amount into the hole before the air needed to be worked out in order to get more in, had I not been confident that there was still a fair amount in there anyway, because the paddle was still fairly stiff to rotate before I started, I would have been tempted to bore a second hole opposite the first to allow the displaced air to come out. I worked the air out with a wooden skewer and got a bit more in rotating the paddle all the time.
Sealed the hole up with a blob of plastic epoxy...…..the damping is increased by some 25% or so....not massively but as I said it was quite firm when I started....however it had bled over the internals so some grease had clearly been lost.
My concern would be that the grease that liquified and leaked out was due to a deterioration of the product. I have seen that in a number of these devices and at the same time have some that are still perfectly intact. I think it is related to the environment the units have been exposed to. Similar to some Beocord 800x-9000 having worn belts while others have belts that have deteriorated into a black glue substance.
Hopefully your fix will work fine but I have to wonder about the state of the original damping grease that was still inside. In the end it isn't critical to the Beomaster working. You will just need to keep an eye on any leakage in the future.
Still, an interesting solution and I enjoyed watching the implementation.
Well.....pro's and con's I suppose....if things don't go well with the damper all I've done is drill a 2mm hole in the case and plug it up, time will tell. Got the control panel removed, awkward exercise depressing the tabs with enough force to release them but not too much to break them ;¬)
Craig: Well.....pro's and con's I suppose....if things don't go well with the damper all I've done is drill a 2mm hole in the case and plug it up, time will tell. Got the control panel removed, awkward exercise depressing the tabs with enough force to release them but not too much to break them ;¬)
Haha, yes a lot of these repairs have pro's and con's. If you think that panel was awkward wait until you remove the display piece to get to what is under that. It is another exercise in carefully navigating some plastic tabs.
Craig: Ok.….here we go, bored a 2mm hole in the side of the damper drum carefully so as not to damage the internal turbine blades.
Hi Craig
It looks like a delicate operation, how did you make sure chips from the drilling did not end up inside the damper?
The damper is a fascinating (and without a doubt expensive) piece of engineering, and very typical for the way B&O approached solutions, sometimes perhaps forgetting the benefits of the KISS principle.
Thanks for sharing the journey, I have a 6000 waiting to be brought back to life, so any tips and tricks a can collect before the surgery improves the chance for a speedy recovery of the patient.
The answer to that is that I'm not sure no swarf made it into the internals, on the balance of probability some will have, will there be damage as a result possibly but I would say unlikely.
Seperated the pushbutton panel from the switch assembly...
Lots of dead skin cells and a crumpled corner of the sticky back plastic...….
As its the standby button I don't know if it was actually working prior to removal......the switch clicks in and out to applied pressure so I suspect it worked fine….however as I need to do something about it I eased it back to reveal the contacts beneath
the flexible contacts did have a small amount of dirty dust on them which cleaned right of with a cotton bud and some alcohol.....thing is do I really need to take them all out? I could do so and gold plate them, but is it really necessary? I will ponder for a while....I don't think it would do any harm.
Swarf... I was looking for that exact word
Do the contact fingers on the PCB have a golden or a silverish luster? Difficult to judge from the picture.
They have a more silver finish....I don't know if they are actually coated with a noble metal like a lot of relay contacts, they look in pretty good shape once the small amount of dust/discolouring is cleaned away
Ok....decision made, die is cast...and new sticky back plastic is on order, 70 micron thick....forrest green in colour. The first task will be to remove all the old adhesive from the board, the plastic sheet came away reasonably well but it wont be getting re used ;¬)
From the looks of the picture it looks like a lot of the T- junctions have been cut in a drill operation?
If that is the case its a telltale sign that the surface protection is electroplated. I am guessing its silver, but the lack of any tarnishing is unusual,- nickel perhaps? Today this would be done using a much cheaper immersion gold (or sliver) process. Impressive to see the level of brute force (best of the best) engineering the guys put into the 6000!
Looking closely at the T-junctions I'm finding it difficult to determine the process used to cut them out, there are no signs of machining, however they are very well put together whichever method was employed. Spent a lot of time cleaning and plating these contacts considering I will be covering everything in sticky back plastic in a few days......
Sticky back plastic sheet was delivered today....cut to size ready to peel back the paper backing and apply....
cut to size and offered up to the board, paper peeled back and plastic affixed, made the cut outs and all looks good...…...
Control panel re assembled and ready to go...…….
Craig: Sticky back plastic sheet was delivered today....cut to size ready to peel back the paper backing and apply....
Can you share what type of backing you bought and where you sourced it?
Thanks,sonavor
sonavor.....ebay special
https://www.ebay.co.uk/itm/BUY-2-GET-1-FREE-1mtr-or-A4-Self-Adhesive-Sticky-Back-Plastic-Sign-Vinyl/222794441744?ssPageName=STRK%3AMEBIDX%3AIT&var=521645968370&_trksid=p2057872.m2749.l2649
Thanks. I hadn't looked at that material before. It looks like the right replacement for these button panel backings.
Tone control board next...dial cord will have to be re-fitted when I'm finished, always have fun with those.
Had to remove this board to get at the two tantals sitting right in front of the tunning motor, will give that a coat of looking at too, and the feedback pot while the board is out.
Theres a lot to be said for these modular boards with the plug connectors, makes things much easier to access....
Micro computer next in the barrel...….
I know there are two fat boys hiding inside the screened enclosure...…..wont be doing anything else in here!
Sort these two out and get out of there...….
Re assembly under way....not had any issues with this unit, which makes a change....
Greatj job so far, nearly at the end. I might be telling granny how to suck eggs, but when you put the black cover on over the LEDs, be Careful of the balance bulbs, I broke two on my rebuild.
I love this unit, it’s just as good as my Beomaster 4400
Keith