The Secret Society of Lathe Trolls

HI, Sorry about the delay responding. I was away on vacation and then came down with the flu. I'm still recovering, so give me some time to respond better. Looks like you did a nice job getting that fabricated (the prints look a bit rougher than my resin printer, but that shouldn't matter). Are you ...

Hi,

I would go with the long shank and cut it down to size. The short shank is probably closer to the correct length, I think it's better to have extra just in case.

Mark

Hi,

Go slow and back the tap out every few turns. I ran the tap through to the hole on the opposite side. Then I blew out some of the powdery residue and ran it through again. Hope it works out for you.

Mark

Hi, You can fry the head if you feed it too much power for too long of a time. 100 watts is quite a bit of power for those old Astatic heads. They were typically run with 5 or 10 watt amps back in the day. Having more power is fine as long as you take some steps to monitor the drive level and keep t...

Hi, I did not use any tapping fluid, but I did go very slowly with the tap. The resin prints are pretty brittle. I'm still very much on a learning curve with my resin printer. If you have the correct tap drill for an M2, did you try running that through by hand with a small chuck prior to tapping? I...

Hi, Are the fans on a thermostat or do they run all the time? The reason I ask is that perhaps you could mod the amp to add that feature. In fact I wonder if you ever really need a fan given that you probably only ever hit the heads with low average, but high peak power. I have no experience with th...

Hi,

Its shown in the photo of the head just above my post with the files. You can also load the STL files into your 3D printer or CAD program to view in more detail. These will need to be printed in a MLCD resin printer. The details are too small for an FDM print.

Mark

Hi, See the attached files for my latest versions. I have two coupler STL files. One has a thicker base. I've been experimenting to see if I can reduce some of the resonances and I think the thicker is a bit stiffer. It does add some mass however. Feel free to experiment. That coupler should be tapp...

Hi Mark, Sorry about the delay responding. I've never owned one of these machines, so I can't really comment on how loud they were able to cut. I suspect that you may be up against the limits of what the head can do. Its unlikely that there are any original heads in working condition to compare agai...

Hi, Sorry about the delay responding. I would give the piezo pickup a try. Remember this is natively a displacement sensor, so you will need to high pass filter (differentiator) the output if you want to correlate to a flat magnetic pickup response. The big issue here is that there are not currently...

Hi, Good job testing and measuring the voltages. It seems like you are getting the correct drive to the head. So that's good news. Down the road, I would recommend replacing the caps, but not until you get the loudness issue solved. I was confused by your second posting. Are you saying that the sine...

Hi, You should be able to get to the top of the chassis. Just might require a bit of work to remove the knobs and some screws. Maybe its just too much hassle. It might work out ok if you add a small axial cap at each circuit point and use the closest ground. You will find out pretty quickly if this ...

Hi, The metal cans should be stamped with the values on the top of the chassis. If you can't read them, then you will need to trace out the wiring. Yes, you need to break the connections to the cans. You can use the lugs as tie points and the common ground can stay. It can get a bit messy to do that...

Hi, Is the PO-80 a one and done thing or is it just out of stock? That's too bad if it is no more as its a really nice little unit that would be perfect for your project. I assume you have seen my thread and some of the other threads on the hacking. I'm planning on posting more about my mods in the ...

Hi, I can't tell from the photo which 2 caps are the 10uf 25V, but you should be able to figure that out by looking at the cans to see the rating and also tracing the circuit. Given that that radio and record player plays fine, I don't think changing them will make any difference. Also, note that if...

Hi, If the record player/radio sounds fine, then its not the electronics. The same signal path is used for the cutter head. Might need to go back to Westech. Contact him and let him know and see what he recommends. It is possible that the output transformer is shorted and not developing the proper v...

Why not just print a QR code on the label.

Another idea would be to record a digital watermark in the audio that you would extract with a smartphone app.

You can also emboss onto CD-R and the digital side still reads fine.

No hardware like a NFC chip needed.

Mark

Hi, If you are looking to use as a teaching aid, I would recommend the Gakken or Teenage Engineering PO-80. Its small, low in cost, and a completer working kit you can build. It has all of the basic parts of a record lathe. There is plenty of room to hack and modify to make improvements (do a search...

Hi, You can limit the high frequency bandwidth which should allow you to cut at a higher level. If you are trying to push the head at the high end, you will eat a lot of your reserve power. You can also explore half speed mastering which will work wonders with both level and bandwidth. With the K8, ...

Hi,

Its interesting that since you made the changes, the main system resonance has moved up and the secondary resonance has moved down in frequency and you still seem to have that interaction.

Mark