Update of MMC Cartridge Box for MMC 1-5 Cartridges

A while ago I designed a storage and shipping container for MMC cartridges. Initially this container was only outfitted with an insert for the old style MMC20 cartridges.

I just designed a new insert specially designed to hold and protect the newer MMC1-5 cartridges:

It opens like a book. Just stick the cartridge in the specially molded holder:

The inserts are printed from flex filament, i.e. are a bit elastic for a gentle and safe fit of the cartridges.

That is how they look closed. A little window shows what is inside:

Beolovely! Like all our parts these boxes are available to other enthusiasts!

Beomaster 6000 (2702) restoration: putting all PCB's back into the main frame

After some vacation, a business trip and a few other urgent repair projects, it was time to get back to the big Beomaster 6000 quad restoration project ! Last time, after a successful test of the unit outside of the main frame (click here), the main power transformer, power caps and rectifier were put back into the main chassis together with the added extra fuse (click here).

When checking all the PCB's and figuring out a way to put everything back into the chassis without desoldering all the boards, I discovered a few issues. The first was the aluminium hooks that I added to the power stage output board (click here) to hold it firmly in place. The glue did not stick....and the hooks where loose. So I decided to glue them back with epoxy  glue to make the bond stronger (in stead of the "one second glue" that I used originally).

The second issue was the main power cord and the way that cable was going to the fuse box. It's difficult so see in below picture, but the cable was outside the transformer box and preventing the subframe with the 4 output stages to sit flat on the main frame. The cable was supposed to be going inside the transformer box.

OK a 10 minutes work. Done. Now let's put everything back in the chassis. Should be easy, if you know how to dismantle something, just do in the reverse order.....Maybe this is true for a IKEA furniture, but not so with a Beomaster 6000 quad ! So many wires that need to be carefully moved around to avoid braking off at the soldering points. Luckily I took plenty of pictures before disassembling and I also have another unit laying open so I can peek inside that one!

But still.......It all looked too big to fit in there....

But after about 1,5 hour of gently moving the whole bunch of PCB's, cabling, subframes, etc., off course it DID fit in there !

Time for a pause now. Next will be a thorough check of all the wires, screws, bolds, etc. before powering it up. And still a lot more to be done: the FM dial display, the dial wheel with the cord, the key panel, some more calibration, the red plexi display and the wood plinth. Stay tuned !

Beolover MMC Cartridge Storage Box: Yet Another Redesign

Sadly, I had to retire my last Beolover MMC storage box design due to inconsistencies in Shapeways' production output. The tolerances requirements for press-fits is fairly high, and Shapeways seems to have variances that are too large. Recent orders yielded parts that were a bit too tight and the cartridges would not fit smoothly anymore.

Triggered by the desire of a customer to acquire a few of the storage boxes I set out to come up with a more robust (in production terms) redesign that can be printed directly by the Beolover Printer Farm. This shows my new approach:

The white insert is printed from a special flexible filament, which gives it a rubbery texture that holds the cartridge securely in place. This insert slides into a hinged hard shell box that protects everything. The insert is held in place by a protrusion from the bottom of the box that clips into a matching opening in the insert.

This shows the box closed:

The 'window' informs about the content of the box. So if one has several cartridges for different listening situations, it is easy to find the right box. Beolovely!

Beomaster 8000: Awesome Find on Ebay!

I often help customers to find a suitable Bang & Olufsen unit on ebay or craigslist, then restore it and then send it on to its new home. Almost like going back to the 70s with a time machine and buying it new at a B&O store...;-). Here the task was to find a Beomaster 8000 in nice cosmetic condition. I always recommend to start any restoration with a nice looking unit, since the value of the finished unit is largely determined by its looks...

Recently a very nice Beomaster came up on ebay including the Terminal remote and the original packaging. It was also sold by the initial owner - always a very good sign! I received the unit yesterday, and it was a happy moment. He had the original box double boxed by a mailing place, and so it arrived in a  huge box under a heap of styrofoam peanuts...not my favorite method - too messy when unboxing and more importantly, the inner box can shift around and individual sides of the inner box can end up dangerously close to the outer box, negating the purpose of the double box. In this case all went well, though.

Here are a few impressions:

As I said, a LOT of peanuts...;-). After I shoveled everything in several lawn bags, I extracted the original box:

then came the moment of truth!:

The original owner's manual! excellent! And then the Beomaster revealed itself:

In pristine condition as advertised! I love it when ebay sellers are honest! In this case it was a very pleasant experience from A to Z. Look at the veneer corners!:

Awesome! Almost like new! The best corners I have seen in some time! Lucky day! 

MMC Cartridge Box: Now Available on Shapeways

What better way to celebrate my 400th beolover post with making the Beolover MMC Cartridge Box available on Shapeways?? It is time for adequate protection for our valuable cartridges!

It was a lengthy and difficult process to get this part designed and I had to go through many design iterations to get the 'feel' right. I desired to have a solid press-fit between the cartridge and the 'base' of the box to afford maximum protection to the cartridge in case someone accidentally drops the base after inserting a cartridge. The top on the other hand was supposed to fit with some, but not too much friction to enable easy access. Some manufacturing tolerances at Shapeways did not help this process either, and so it took me many design iterations and test prints to get to a point where the print outcomes between different print-runs were satisfactory.

So here we go: This shows the bases with cartridges inserted and the matching tops:

And with closed tops:

And why not get base and top in a duo-tone combination??:

There are 49 color combinations possible as they are available in seven colors...check out the parts at my Shapeways store!

Or use these direct links below for ordering. You can select the color during checkout. It usually takes about two weeks to get parts from Shapeways in most parts of the world.

MMC Cartridge Box: Another Iteration

This is a follow up to my recent post about the design of MMC20 and MMC4000/6000 cartridge storage boxes. I just received the next iteration from Shapeways. I changed the lettering on the covers and also designed a cover with a view port to directly see what type cartridge is inside. Here are a couple of impressions:

I also made the covers a tad thicker in the hope to get a tighter fit, but now they are a bit too tight for my taste. So, I guess the next iteration may be the final one...;-)

MMC Cartridge Box: A First Impression

I accumulated a few MMC20 and MMC4000/6000 cartridges over the years, and I only have a couple protective covers. I always wanted a better solution for keeping them safe. Protecting them definitely makes sense considering the prices they fetch these days in good condition. So I set out to design a 3D printable small box. First I took exact measurements of a MMC20 cartridge and built a model in Inventor. Then I created the lower part of a box moulded to the metal housing of the cartridge and a cover.

Yesterday I received the third version of the design from Shapeways, which finally seems to fit the cartridge perfectly, and also has enough friction between the cover to give a nice open-close feel. The issue with 3D printing really is that every technology and material behaves differently, while having specific tolerances and 'quirks'. So it takes a bit of trial and error to get a working product from a CAD design. Well, here are a few impressions:

This shows the empty container. The bottom part shows the characteristic slant of the bottom part of the cartridge. The front part is cut out deeply to make sure that the cantilever and tip never touch anything:

Pretty amazing the resolution that Shapeways can achieve. The slightly grainy surface is a result of their Selective Laser Sintering (SLS) process that blasts the plastic granules in the printing bed to fuse them into a solid body. 

And here with inserted MMC20CL cartridge. The cartridge body makes a nice smooth press-fit with the part to ensure protection even if turned upside down:

And closed. The cover shows the cartridge type on top:

I think I will redesign that a bit with bigger lettering. I will make a specific cover for each MMC20 and the MMC4000 and MMC6000 models that one can easily find the desired one. Shapeways also offers a bunch of nice colors, i.e. color coding will be possible, too.

Stay tuned for the final version...They will be offered at the Beolover Shapeway store.