i am going to make my own lathe ground up together with a team of engineers in denmark.
we ask if anyone have tried the making of the cutterhead, because the rest is doable right now. the cutterhead however is making trouble.
how is the needle placed in the cutterhead.
how is the needle connected to the two drives
what is holding the needle? are there springs or what?
kind regards
johannes gårdsted jørgensen
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johannesgj
- Posts: 4
- Joined: Mon Oct 19, 2009 7:27 am
Hi,
Are you doing this to create a product that will be made available for sale? Why a team of engineers? If you have acess to this much brain power, surely you can do the reasearch on your own. You don't need us to give you all of the details. You poll asks if it can be done. The answer is yes. I've made a decent attempt. I'm still working on improving my design. When I finally get it to a good point, I'll share any and all details for others who want to tinker as a hobby, but I don't want to see it used for a commercial product. Consider it open source hardware.
Mark
Are you doing this to create a product that will be made available for sale? Why a team of engineers? If you have acess to this much brain power, surely you can do the reasearch on your own. You don't need us to give you all of the details. You poll asks if it can be done. The answer is yes. I've made a decent attempt. I'm still working on improving my design. When I finally get it to a good point, I'll share any and all details for others who want to tinker as a hobby, but I don't want to see it used for a commercial product. Consider it open source hardware.
Mark
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johannesgj
- Posts: 4
- Joined: Mon Oct 19, 2009 7:27 am
just to make this clear.
we are first year students, we are besides studying developing open-source software in most of our sparetime. which is freely accessible to anyone.
being elektro engineer dosen't meen i will or we will have automatic knowledge of the mechanical skills needed for the understanding of the needlework and fine mechanics.
so the reason i ask questions is because i need answers. not because i am lazy or something. i have been making research on this subject on and off for a year, but haven't until now had any time to get into it practically.
if you have knowledge of this kind of project, and i mean deleopment of a diy cutterhead please share even though your project might not be finished or even working only together people can learn.
i used to put all my knowledge up on a google notebook which is public, but now i got a blog which i'll use for that matter.
check here
http://antima55.blogspot.com
with hopes of future mutual knowledge sharing.
kind regards
johannes gårdsted jørgensen and others
we are first year students, we are besides studying developing open-source software in most of our sparetime. which is freely accessible to anyone.
being elektro engineer dosen't meen i will or we will have automatic knowledge of the mechanical skills needed for the understanding of the needlework and fine mechanics.
so the reason i ask questions is because i need answers. not because i am lazy or something. i have been making research on this subject on and off for a year, but haven't until now had any time to get into it practically.
if you have knowledge of this kind of project, and i mean deleopment of a diy cutterhead please share even though your project might not be finished or even working only together people can learn.
i used to put all my knowledge up on a google notebook which is public, but now i got a blog which i'll use for that matter.
check here
http://antima55.blogspot.com
with hopes of future mutual knowledge sharing.
kind regards
johannes gårdsted jørgensen and others
Hi,
Here is a link to my crude web site with some pictures of my head and lathe. If you have any questions, feel free to ask. Make sure to look at the photos (If you click on them, you will see higher res versions).
http://home.comcast.net/~markrob1066/site/
Mark
Here is a link to my crude web site with some pictures of my head and lathe. If you have any questions, feel free to ask. Make sure to look at the photos (If you click on them, you will see higher res versions).
http://home.comcast.net/~markrob1066/site/
Mark
To Johannesgj
Yes it is totally possible to design and build a cutterhead, it's not complicated and it's all been done before. It is basically 2 voice coil motors (with feedback coils) coupled together by use of a tool (stylus) holder that is sprung so that the stylus returns to its resting point. Neumann used BeCu springs, mounted at the opposite end to the stylus, the axes of which match the motors' in this case springs are flat not coiled.
Research "voice coil motors" and "loudspeaker design" these are the same device in different applications all the maths required is covered by these two applications, many voice coil motors have feedback coils, so there are many documented designs on the web. You will need good engineering facilities like a lathe, mill, coil winding machine, measuring eqpt. Start point for design will probably need to be with the magnets, unless you are designing/making your own magnets, you need to find suitable magnets and design around them.
Research "voice coil motors" and "loudspeaker design" these are the same device in different applications all the maths required is covered by these two applications, many voice coil motors have feedback coils, so there are many documented designs on the web. You will need good engineering facilities like a lathe, mill, coil winding machine, measuring eqpt. Start point for design will probably need to be with the magnets, unless you are designing/making your own magnets, you need to find suitable magnets and design around them.
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johannesgj
- Posts: 4
- Joined: Mon Oct 19, 2009 7:27 am
thanks so much for the reply!
this knowledge gives me a fast step forward!
is it ok if i quote you on my website. i try to make a project site around the idea, just to make it easier for others to do this as well.
will write back soon!
thanks again
- johannes
btw. my website is at
http://antima55.blogspot.com
is it ok if i quote you on my website. i try to make a project site around the idea, just to make it easier for others to do this as well.
will write back soon!
thanks again
- johannes
btw. my website is at
http://antima55.blogspot.com
Hi,
I would highly recommend the paper:
"Methods of High Quality Recording and Reproducing of Music and Speech Based on Telephone Research" by Maxfield, J.P. and H.C. Harrison Am. Inst. Electr. Eng Trans. 45:334-346
This was published in 1926 and is one of the first papers to detail the math required for cutterhead design. It will give you a good basis to start even though the head is a moving iron type, mono, and low-fi by today's standards. Hopefully, you can find it in your school library.
For design info on more modern moving coil type heads see:
"Lateral Feedback Disc Recorder" by G.R. Yenzer Audio Eng. 33:22-27 (1949)
This describes the first Westex mono head.
If you did not find it on my web site, see the description of the Sugden stereo head. Also there is a great technical description of the BBC Grampian head.
Finally, be sure to chech out this site for downloadable technical textbooks:
http://www.pmillett.com/technical_books_online.htm
In particular, see the Oliver Read book and the Radiotron Designer's Handbook.
Hope this is of help.
Mark
I would highly recommend the paper:
"Methods of High Quality Recording and Reproducing of Music and Speech Based on Telephone Research" by Maxfield, J.P. and H.C. Harrison Am. Inst. Electr. Eng Trans. 45:334-346
This was published in 1926 and is one of the first papers to detail the math required for cutterhead design. It will give you a good basis to start even though the head is a moving iron type, mono, and low-fi by today's standards. Hopefully, you can find it in your school library.
For design info on more modern moving coil type heads see:
"Lateral Feedback Disc Recorder" by G.R. Yenzer Audio Eng. 33:22-27 (1949)
This describes the first Westex mono head.
If you did not find it on my web site, see the description of the Sugden stereo head. Also there is a great technical description of the BBC Grampian head.
Finally, be sure to chech out this site for downloadable technical textbooks:
http://www.pmillett.com/technical_books_online.htm
In particular, see the Oliver Read book and the Radiotron Designer's Handbook.
Hope this is of help.
Mark
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johannesgj
- Posts: 4
- Joined: Mon Oct 19, 2009 7:27 am
hm funny.... I was just a medical student and I could find anything you're asking just by checking this forum. 
I know it's quite extensive forum but you can find practically everything here. If you prefer the paper I recommend DISK RECORDING VOL.1 & 2 edited by Stephen F. Temmer published at AES.
here is the link where you can also order these books (it's actually the collection of articles so you can follow the evolution of disc recording): http://www.aes.org/publications/anthologies
the only problem there is - you have to have a lot of time to check all the threads you need. good luck!
I know it's quite extensive forum but you can find practically everything here. If you prefer the paper I recommend DISK RECORDING VOL.1 & 2 edited by Stephen F. Temmer published at AES.here is the link where you can also order these books (it's actually the collection of articles so you can follow the evolution of disc recording): http://www.aes.org/publications/anthologies
the only problem there is - you have to have a lot of time to check all the threads you need. good luck!
https://lathetrolls.com/viewtopic.php?t=796&mforum=lathetrolls
I think it's exactly what your looking for.
I think it's exactly what your looking for.
IT NEVER PAYS TO BE A PIONEER
Generally anything can be built given the motivations. But should you?
I would say building a head would only make sense if you are going for a nice feedback design and had exact specifications for everything in detail (practically impossible). Otherwise, you may be building something experiemental that may not even work. Research and developement is very very expensive. It is today and it was back when most of these old heads were engineered.
As for building a lessor head in the Presto league, I would not even waste the effort. You can buy one much cheaper IMO.
I would say building a head would only make sense if you are going for a nice feedback design and had exact specifications for everything in detail (practically impossible). Otherwise, you may be building something experiemental that may not even work. Research and developement is very very expensive. It is today and it was back when most of these old heads were engineered.
As for building a lessor head in the Presto league, I would not even waste the effort. You can buy one much cheaper IMO.
Does your lathe produce good results?markrob wrote:Hi,
Here is a link to my crude web site with some pictures of my head and lathe. If you have any questions, feel free to ask. Make sure to look at the photos (If you click on them, you will see higher res versions).
http://home.comcast.net/~markrob1066/site/
Mark
Hi RVonse,
I agree R&D can be expensive if your trying to build a commercial product. In my case its a hobby, so R&D is just about free. I have spent some money on textbooks, tech papers, and raw material. But I don't have that much actual cash invested. IIRC, I built the head over the course of a week or so working when I had time in the evenings. I had a basic idea of what I wanted to do. But it was really ad-libbed on the fly. I spent a fair amout of time making test cuts, measuring perfomance, and coming up with an EQ curve to flatten the response.
I have no illusions of creating the next SX74, but I think with some work, I can get the performance to a decent level. Look at what Vinylium and the folks at Vinylrecorder have done. I doubt they spent tons of Euro's to get the design together.
Its been awhile since I cut with the DIY head and lathe (I've since been playing with my 6N lathe, Grampian and Presto heads). But, I did get pretty decent results before I stopped. I have to look back through the stack of test cuts I made with the head and see if I can post an example. I got the best results doing half speed cutting. At the time, I was cutting using my home made stylii. I'm sure I'll get better results with a Transco stylus.
I've recently started to revisit the design and I want to mount it on my 6N. Its not so easy, since there is not much room to work with and I don't want to make major changes to the mechanics of the lathe. Based on what I've learned over the last year or so, I think a second pass will yield some nice improvments. My goal is to post some plans if I get something worthy.
I don't agree that feedback is a requirement for a good head design. I'm interested in it for the technical challange. Its hard to close the loop over the full audio range without having stability problems. In fact, the open loop design needs to be free of bad secondary resonances or it will be a mess to deal with.
Mark
I agree R&D can be expensive if your trying to build a commercial product. In my case its a hobby, so R&D is just about free. I have spent some money on textbooks, tech papers, and raw material. But I don't have that much actual cash invested. IIRC, I built the head over the course of a week or so working when I had time in the evenings. I had a basic idea of what I wanted to do. But it was really ad-libbed on the fly. I spent a fair amout of time making test cuts, measuring perfomance, and coming up with an EQ curve to flatten the response.
I have no illusions of creating the next SX74, but I think with some work, I can get the performance to a decent level. Look at what Vinylium and the folks at Vinylrecorder have done. I doubt they spent tons of Euro's to get the design together.
Its been awhile since I cut with the DIY head and lathe (I've since been playing with my 6N lathe, Grampian and Presto heads). But, I did get pretty decent results before I stopped. I have to look back through the stack of test cuts I made with the head and see if I can post an example. I got the best results doing half speed cutting. At the time, I was cutting using my home made stylii. I'm sure I'll get better results with a Transco stylus.
I've recently started to revisit the design and I want to mount it on my 6N. Its not so easy, since there is not much room to work with and I don't want to make major changes to the mechanics of the lathe. Based on what I've learned over the last year or so, I think a second pass will yield some nice improvments. My goal is to post some plans if I get something worthy.
I don't agree that feedback is a requirement for a good head design. I'm interested in it for the technical challange. Its hard to close the loop over the full audio range without having stability problems. In fact, the open loop design needs to be free of bad secondary resonances or it will be a mess to deal with.
Mark
YES EVERYONE SHOULD MAKE AN CUTTING HEAD
Should you make a cutting head???
Yes definitely, i think any enthusiast interested in this technology, should take inspiration from the work already shown on this forum, and take designs further. If you want hands on experience with cutting records and associated eqpt - unless you've got lots of £$£$ to spend or lucky enough to get a rare job in this trade - it's not going to happen, unless of course you build your own equipment! If you look at engineering hobby forums and sites, the hobby has got to a point where surprisingly complex and effective projects are being successfully being constructed at home by enthusiasts. The same thing needs to happen with disk cutting, but it needs people to take part in constructing eqpt, finding usefull off the shelf bits and pieces, working out ways of problem solving etc etc
So if you're thinking about doing this please do it and let us know how it goes.
Rog
Yes definitely, i think any enthusiast interested in this technology, should take inspiration from the work already shown on this forum, and take designs further. If you want hands on experience with cutting records and associated eqpt - unless you've got lots of £$£$ to spend or lucky enough to get a rare job in this trade - it's not going to happen, unless of course you build your own equipment! If you look at engineering hobby forums and sites, the hobby has got to a point where surprisingly complex and effective projects are being successfully being constructed at home by enthusiasts. The same thing needs to happen with disk cutting, but it needs people to take part in constructing eqpt, finding usefull off the shelf bits and pieces, working out ways of problem solving etc etc
So if you're thinking about doing this please do it and let us know how it goes.
Rog