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.

MMC20 Cartridge Mount Replacement: Second Design Iteration

This is a follow-up to my initial post about the design of a MMC20 cartridge mount replacement. In the meantime, I acquired a Beogram 4000 with a broken off mount, so now this is 'personal'...;-). Ouch!:

I just received the redesigned Version 2 prints from Shapeways. The main issue with the initial version was that the back part would not fit on the lower part of the original mount that will be reused, and that the contact tab would make intermittent contact. I realized that the issue was the 'bump' that I designed into the tab to press the contacts into the cartridge contacts. One I looked at the broken off tab of my Beogram 4000, I saw that a simple straight shape should work. So version two of my design aspires to closely resemble the 4000 version of it.

Here are a few impressions. Along with the changed shape, I also needed to redesign the tool bodies that are used for pressing the circuit board into the mount while the glue dries:

Hers is a picture of the curing process:

And here the result in comparison with the original mount (this one is from a later Beogram and was supplied by Sonavor (Beoworld)):

Then I tested it on a MMC20S cartridge. It made good Ohmic contact and I measured the usual 770 Ohms per coil:

This iteration now fits very well on the lower (original) part of the assembly:

Consequently, the part also fits into the arm tube:

However, the mounting angle is a bit too steep. From the gap, using a protractor, I deduced that I need to reduce the angle by about 4 degrees. Oh well, back to Autodesk Inventor for Version 3.  While I will be waiting for the Version 3 prints I also need to figure out how to plate the PCB traces with gold to ensure long term stability. We do not want to have oxide layers getting in-between our precious vinyls and our ears...;-)

Designing a new part: Quite a laborious process - A resuscitated Beogram 4000: Priceless! This is Beolove!

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.