Deep Grooves Mastering - Opcode66 Transducer Project

[opcode66]

For some time now, I've made a study of coil winding. I've completed a number of coils for Mono Cutterheads with fantastic results. So, I decided to start making my own transducer...

I 3d Desinged and Printed the parts for the transducer: Base with Magnet holder, Bobbin, Cover and Frame Bracket. I have two Neodymium rare earth magnets in the base. I used a Jewelers Mill to make flat enameled wire. I wound my coil by hand. Aligning each turn manually with a blunt dentist's instrument. Coil #1 was 55 turns in 3 layers, and it measured 3.7 Ohms Resistance. After a brief bit of math, I rolled my second coil. Coil #2 was 100 turns, 4 layers and it measured 6 Ohms Resistance. That means Coil #2 had an Impedance in the ballpark of an 8 Ohm speaker. I could therefore attach Coil #2 to a standard home stereo amplifier.

I was completely blown away by the results. I think you will be too. Cutterhead to follow!!!!

http://www.youwantvinyl.com

[Stevie342000]

Absolutely we should all be excited at this, as there are so few people out there who are making cutting heads.

The options are limited if you just require a cutting head i.e. Caruso thanks to Flo. There may be others.

Many of the people who had the knowledge have fallen off the edge of the cliff of time and the remainder are very near the edge.

Have you looked at balsa wood as a former it's light and easily workable. I know it is what AR Sugden used so we know it works. You could fabricate the other parts out of plastic using a 3D printer.

But we need to look at workable alternatives as the issue is heat build up and melting. But if spare coils were provided and they were at a reasonable cost then that would be a work around.

I am personally thinking if you have the patents or an old head to work on by any manufacturer you could offer the service of head rewinding? Did you see the other thread on how to rejuvenate the magnets? I had been planning to do that with mine. The original Sugden head are now a bit weak as I may have broken the magnetic loop when I took a peek in the front.

It's a shame you can not look at ceramics for the former and or other parts to get around head build up?

Needless to say you latest experiment does have legs and there are a number of avenues you could explore. Repair, new manufacture and a full head in mono or stereo with or without feedback. There are plenty of old drawings, manuals and patents to work from. The BBC Grampian comes to mind as one as there is a full set of drawings to work from.

As for me I lack the money, the equipment to do many of the experiments to get a new head design up and running. But why re-invent the wheel refinements can be made with today's technology and techniques. In addition I am very good at a concept and an idea but lack the facilities to take it further as do many of us.

Your efforts have not gone unnoticed by me at least and the time/effort will pay off in the longer term.

[opcode66]

I'm working in plastic for now. Let's call it rapid prototyping. I think a finished product will be almost all metal.

It should be noted that I had the volume cranked when I smoked the coil. So, given reasonable expectations that wont happen again. I'll add a 1 Amp fast blow fuse inbetween the amp and the transducer. That will provide coil protection.

I'm going to build two more transducers tomorrow. As well as print the cutterhead body you see below. I need to finish a back mount for neumann suspension and a torque tube assembly. I also need to sort out a spring for inside the transducer. Then, more testing!

If all goes well, I'll add feedback coils next!

Please have a look at my other post here http://lathetrolls.com/viewtopic.php?f=15&t=5205 regarding mono coil winding. I can now in fact provide mono cutterhead repair service.

[Stevie342000]

Good news, I had checked out the Youtube clip on rewinding a RCA cutter head coil. Agreed metal would be good but you may need to look at heat build up in the coils, we do not all have helium cooling.

However just an idea perhaps it could be pre-looped in as part of the vacuum system, which may carry some of the heat away. I like the idea of slide in slide out cutter assembly with a face plate to hold it all in place.

[tragwag]

excellent!

[Babooino]

great todd! what's the wire gauge?

[chaosbc]

few questions :
- What is exactly the benefit of having flat copper wire instead of a round one ?
- Is it necessary the wire to Alignin each turn ? (I mean is it to get a "cleaner" construction or is there a specific (magnetic?) reason?
Oh by the way, That's a nice project ! I suppose everyone here is going to be a 'windowlicker' (nudge nudge)

[Babooino]

few questions :
- What is exactly the benefit of having flat copper wire instead of a round one ?
- Is it necessary the wire to Alignin each turn ? (I mean is it to get a "cleaner" construction or is there a specific (magnetic?) reason?
Oh by the way, That's a nice project ! I suppose everyone here is going to be a 'windowlicker' (nudge nudge)

Curious too!!

[mossboss]

Simple guys
Flat wire=greater contact/induced flux area
Take two round pencils lay them flat on your desk next to each other, look at them end on, what do you have?
Take two square or rectangular items like 2 CD cases, stick them together on your desk, look at them side on, where is the gap??
Cheers

[opcode66]

FYI, I'm going with a modular design for the transducer cards. If you blow a coil, you can just pull out the card and replace with a spare card. I'm making them with a row of pins. The cutterhead body has the reciprocal female sockets. When the card slides in, all are aligned. That would mean zero downtime!

There is a cavity in the body of the cutterhead that starts in the back and branches to each card slot. That is for helium. Things are going really well so far.

[opcode66]

More pics

[opcode66]

Need to design a torque tube bracket and something to hold a vacuum tube. Then, I'll wind two more drive coils and make a 2 pair cable long enough to make a proper test. Then, on to my Neumann for a proper test! I think that I should have the other pieces done by the end of the day tomorrow. Including the coils. Not too shabby for about one week's labor. Metal next, of course.

[Stevie342000]

Looking good so far so much progress in a week. Of course there will be nothing less than some videos of the prototype in action?

Any ideas or a ball park figure on a selling price?

I thought you had figured out for this have quick interchangeable cutting coils, that should be no excuse for over-driving and burning out coils.

Looking forward to the next stage in metal, which may take a bit more than a week to knock up. Assume you are looking at alternatives to just a Neumann adapter?

[opcode66]

I can design any kind of adapter you like. I'm also going to make some mono heads in plastic for cheap!

Metal will come later. After I get a working prototype in plastic. I'll have metal parts machined at that point.

[Stevie342000]

That sounds like a good plan.

Will there be a cheap stereo cutting head? Would fill a lot of peoples purpose and give them the opportunity to learn. Along with upgrading at a later date?

All looking good, awaiting further updates.

[Snakeheadfishlab]

Where do you get flat wire?keep doing what your doing,you rock!!


Sent from my iPad using Tapatalk

[opcode66]

I mill it myself from round.

As far as a cheap stereo option is concerned, I could sell the sell the head in plastic for significantly cheaper. Though I am unsure at the moment what kind of results it will give in plastic.

[opcode66]

More progress. Almost done with all the parts!!!

[Stevie342000]

It might just work in Plastic or with some parts in metal. You will only find out where the weak points are once you test it out.

Either way it is looking good...keep us posted.

[ROLANDJAYS]

I already tried this, and plastic is super heavy, compared to the weight of other parts on cutter heads.
up to 4 times heavier.
but try it out any way..... cant hurt