The Secret Society of Lathe Trolls

chaosbc wrote:I am no way affiliated to aliexpress but : http://www.aliexpress.com/item/Large-Surface-Transducer-with-Wires-4-Ohm-5-Watt-4K-5W-Free-Tracking-Number/2020210299.html

That's a great price. I think I paid $24 each for the ones I'm about to play with.

Bryan

I'm saying this is something that is not present in your design. So, probably best not to guess at things that are present in your design. Best to guess at what is absent. Todd, this is fun and educational. Thanks for putting up with me. Your head has several advantages. 1). You are using a press f...

But, you still don't have the secret knowledge. Has nothing to do with centering the torque tube after sound stops. Has to do with keeping the tube parallel? Guess a V mounting at the rear rather than a single mount point. Like yours until you glued them in place. :P I bet you are changing those in...

opcode66 wrote:There is one additional critical factor that you haven't mentioned...

Holds the stylus, and keeps it from pulling forward when cutting?
Share the #SecretKnowledge. Share the #SecretKnowledge. Share the #SecretKnowledge!

I should also add a photo of what the setup looked like with piano wire...
And how bad the over-modulation was when I just about blew the divers.
Bryan

I also learned that it is called a torque tube for a reason. Without understanding that the tube does in fact torque.... It has a rotational aspect to it, ie torque. But in a conventional sense it also supports the upward force from cutting. The tube has to rotate as the L and R push rods try to do...

Let's go over how things went this weekend. As you know the driver discs got installed off center, last ditch push rods were installed with flex in them... After some extra messing around with the Presto to tune down some rumble, some more of the LF noise is gone. I tested the head with nylon, carbo...

I made some response measurements on the bench using a Kaman Eddy current position sensor I got cheaply from eBay. Mark, I'm very interested in your eddy current measurement. First, can you tell me where the measurement was made? At the stylus or the holder or other? Did you buy a sensor with modul...

like yourself I have been trying to keep the moving mass as low as possible I am starting to realise how difficult it is to maintain the required geometry during the build Hey emidisc, great progress there. It's so fun to see other peoples versions. Looking forward to seeing your results. Are you u...

opcode66 wrote:In fact, it isn't really buzzing. It is simply distorting. That is how the phono pre-amp sounds when over saturated.

Ok, I'm with you. Just was going by the audio in the YouTube video.

Bryan

That sort of buzzing in my recording is my 700 hz resonant frequency. Todd, is it possible that the slide in driver cartridges need something between them and the housing? Like some kind of non hardening liquid gasket material - something like "permagasket"? I wonder if something that stays flexibl...

CONTINUED FROM PREVIOUS POST I mentioned playing around with 3mm tubing for the push rods. The big issue was how to attach it. I found a product called Alumiweld, and bought some at Harbor Freight. It has a much lower melting temperature than normal Aluminum and can be used kind of like solder or b...

My new phono cartridge arrived and I ran frequency sweeps and did some listening to some old favorites. WOW! That’s more like it. Now I’m confident in my playback and ready to do some test cuts. I’ve messed with a bunch of things in this down time, and here are some updates. We already discussed the...

For your replacement grommets, do you have any information on the material you cut from? I don't. It was left over from another project and came from the scrap bin at the rubber place. For the other project I bought several types by the pound. That piece looks like it was a section of an industrial...

Lot's of stuff to go over. I'll have to do this over several posts. I've had to hold off with my great mechanical updates and lessons learned, because I discovered my playback cartridge (an M95ED from the late 70's) is toast, and all previously obtained data is total crap. Wow! Let's dive into that ...

Carbon fiber seems seldom addressed in this blog. It is easy to form, modify weight of [add more resin to match weight], has very high heat handling, and is very rigid. Bennett, you are right. I discovered tonight I could get rods and hollow tubes at the local toy and hobby shop (in some sizes, not...

Very reasonably priced. Less than Caruso. ...I plan to supply the cutterhead with one set of spare transducers cards and an instructional video on how to change them out. Todd, please elaborate: Head, plus spare transducers, and are you providing populated Caruso cards, or unpopulated with the opti...

Forgot to add this photo of what the driver disc looks like on the driver....

OK, It's been too long since the last update. Many changes are coming into focus. Tonight I'll discuss the driver discs. Tomorrow I'll hit on the stylus holder. The next day I'll discuss the push rods. By then the weekend will be here and I'll get it all together for another go! So the big issue as ...

I was just thinking and I know you may not agree with this but it might save you some money. Thanks for the note Steve. Your note has merits and I'll try them out for other experimentation I plan to do like those "playing the bones" X-Ray discs. The costs I'm running right now is high, but no worse...