| percy |
I am thinking of dumping the plastic headshell on my BIC 960 turntable and see what I can do to put a better headshell with a better contact with the tonearm. Here is how the end of the tonearm looks like after removing the stock headshell -
First, are there any ready made headshells that I could clamp/sleev over the open end of the tube ?(The outside diameter of the tube is 5/32"). Like the one on this Formula 4 arm -
http://www.audioinvest.no/tt_vinyl/...ms/ta_f4iii.htm
If there are any members who could fabricate one for me please do let me know!! (email or pm). |
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| bulgin |
Hi Percy
You seemingly trod where angels fear to step! Why did you remove the old headshell? Was it too floppy? I once did this years ago with a Beogram 1000. At the time I was too poor to afford a new SP7 or whatever from B&O. Besides I wanted to also play 78's. I rigidly bonded an all metal headshell and on it, I could have a much wider choice of cartridges.
I too stil have an acute shortage of headshells. I've got plenty of the plug-on (sme) type but the arms I use now are Micro's & Grace. Each of these headshells are different which make things difficult to change carts.
I suggest you look at the front end of the Clearaudio 'Satisfy' arm, which looks simple to make.
bulgin |
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| percy |
are you saying I am rushing in like a fool ?
well the whole cartridge->headshell->tonearm connection/arrangement just doesn't seem right, or lets just say there is a lot of scope for improvement.
Besides, this turntable was free so I could use it as a 'learning platform'. I have nothing to loose, all I can see is an opportunity to gain. |
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| EC8010 |
| You can make a headshell out of 1 1/2" aluminium angle (1/8" thick). I made this with the assistance of a Black & Decker power drill in a stand, a junior hacksaw, and a few files. |
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| bulgin |
Hi Percy
I didn't say anything about being a fool!!! It takes b#lls to remove a fixed headshell from an arm before planning what you are going to replace it with. This is only my personal view and no slight on your skills was intended.
Here is another idea but you would have to find an old scrap arm if you haven't any: How about fitting a female screw collar device (devised by sme originally) in the place of the old headshell. This way, you would have a wide choice of headshells.
@ EC8010
This is really excellent work with the tools you had available. The most difficult part would be to fabricate the male socket end which would involve turning an outer metal sleeve and an inner plastics cylinder, precision drilled to take the mating pins or tubes for the arm end, or is the shell going to be fixed?
Sooner, rather than later, I would also have to make a plan for additional headshells for the arms in use as I change carts all the time.
bulgin |
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| EC8010 |
Thanks bulgin. The headshell in the photograph was originally simply glued with epoxy to a Thorens TD166 arm "wand". Two years later, the bicycle style cup and cone bearings in the arm wore out, so the arm was ditched but I kept the headshell. The headshell is now on a Minisonic arm, and now that I have a lathe, acquired a bush to allow better fixing.
About twenty years ago, I made another headshell to the same design but cut a slot in the headshell near the arm tube hole using a jeweller's saw, then drilled and tapped 8BA across the slot to make the headshell clamp the arm tube (thus allowing adjustment). That headshell is still on a friend's Dual 505. |
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| percy |
EC8010, that is exactly what I had in mind!
I am also tossing around the idea of removing the socket from readily available headshells and then fitting the headshell over the wand. Or keep the socket and trim the locking pins if the entire socket fits inside the tube.
bulgin, the collar device might be worth checking into. Do you have a picture or link to it anywhere ? |
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| EC8010 |
| But all SME-type headshells are straight. You need one that angles the cartridge... |
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| percy |
| oh so they dont have the slots which allows a cartridge to be mounted at an angle. That's not gonna work. I need a 24°-25° degree angle (based on John Elison's spreadsheet for calculating Baerwald or Loefgren alignment). |
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| bulgin |
Hello EC8010
I acknowledge making your own headshell is skillful work and my 'hat' (I don't wear headgear!) off to you. I have access to my own small stock of various types of aluminium (incl angle) and I also know some headshells are made from an alu/magnesium alloy. I however also work with titanium for making jigs and have a supplier in Johannesburg where I buy small quantities from.
I think when I try my hand at making some headshells, I may use titanium as it is very light and will wear much better. This metal is not all that expensive, as I found out when I started using it.
I just would love having about 6 headshells for each of the arms I use here and to make these (12pcs) would be a lot of work. The guys with cnc facilities will probably give you 101 reasons why NOT to do the job for you and I may try getting the flat parts lasercut. The rest I'll machine.
@ Percy, I hope you solve the problem.
bulgin |
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| EC8010 |
Actually, making that headshell wasn't nearly as hard as you might think, it just required patience. Sadly, I'm reaching the age where you begin to see the point of hats...
Isn't titanium rather hard to work? Or at least, that's always what has been claimed when the prices of titanium bicycle frames are discussed. |
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| percy |
EC8010,
can I post the picture of your headshell on other forum(s) in regards to my question ? |
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| EC8010 |
| You may, so long as it says, "Made in UK by EC8010." |
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| bulgin |
Hi EC8010 & Percy
Sorry re the stupid tip about the sme sockets. If you go this route, you's still need headshells with offset holes/slots and there aint any as far as I know.
Titanium is hard but I usually mill with tungsten carbide cutters.
Cutting threads are difficult but can be done.
bulgin |
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| steenoe |
| quote: | | Sorry re the stupid tip about the sme sockets. |
Not so stupid at all ;) Any chance someone could point to a source of SME socket's and plug's?? A DIY headshell makes all of us listen up:D Also when a SME is needed;)
Steen:) |
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| EC8010 |
| As it happens, I have both a fixed SME3009SII headshell and a removable one (plus mating socket). |
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| steenoe |
| quote: | | As it happens, I have both a fixed SME3009SII headshell and a removable one (plus mating socket). |
Any chance to see a pic?? I need only the removable thing though.
Steen :) |
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| EC8010 |
| If you can wait until Saturday, I can post a picture. |
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| bulgin |
Hi
I've salvaged two of these sme-type female 'screwed collar' headshell mounts over the years. I think these are some of the neatest, most secure fittings for headshells if you don't have an issue with removable headshells (which I don't have). There are 2 Micro arms and one Grace G-727 Gyromaster arms here in constant use. For these three arms, I've only got 1 headshell per arm, so the need for more headshells is great.
Like EC8010, I have inhouse machining facilities but just cannot motivate myself to start messing about with these arms.
Another solution to the problem would be to remake duplicate headshells but the male fittings at the back are the main problem.
I can precision mill the alloy shell, precision turn and drill the 4 holes for the armlead sockets into a suitable high temperature plastic, but here is the snag: both male headshell plugs have a flat machined on the one side (no problem) and a RIDGE at the other side. In other words, the only round sections of the headshell plug end are the top and bottom.
If I were to make duplicates for these arms, I will have to make the corresponding female fittings as well, each with four pins on the inside...
Therefore, still the best solution would be to turn 3 new mounting tubes (for my situation), configured to take the sme - type locking collars and fit these securely to each of my arms. Then to make headshells with offset slots and fabricate the male parts .
This sounds like a mountain of work fit only for a cnc precision machine shop.
bulgin |
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| EC8010 |
| Because your cartridge needs to be at an angle. All the removable headshells I've seen are for SME-type arms with a curved arm tube. |
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| percy |
I dont know exactly how much wide those cartridge mounting slots are in the first two headshells but isn't it possible to mount the cartridge at an angle in one of those ?
although is it neccessary that all of the mounting surface area of the cartridge makes contact with the headshell ?
for the last two they already have some amount of angle so it seems like it'd be just a matter of "fine-tuning" the zenith. |
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| EC8010 |
| quote: | Originally posted by percy
Although is it necessary that all of the mounting surface area of the cartridge makes contact with the headshell? |
Oddly enough, I was looking at an SME headshell and wondering that exact same thing a few minutes ago. I've always made my headshells like the one in the photograph because I've usually made my arm to suit my cartridge, and none of my cartridges have had any mounting surface forward of the screws. But what if you had a Koetsu or something that was effectively a big rectangular block with screws in the middle? If you imagine that you only support at the screws, then it's easy to imagine the cartridge rocking at that point. Supporting at each end would stop that rocking. So, I conclude that if your cartridge can be suported at each end, then your headshell should do so. In which case, my design would need to be extended forward a little.
I doubt if the slots on a straight headshell would allow you to rotate a cartridge by the 22 degrees typically needed (9" arm), and even if it could, it would look rather messy. |
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| EC8010 |
| quote: | Originally posted by bulgin
This sounds like a mountain of work fit only for a cnc precision machine shop. |
I agree. It's one thing to accept that making something yourself takes a great deal of time but is worth it because of the satisfaction at the end, but quite another to do a load of repetitive work. I once made seven little aluminium buttons in the shape of top hats, each drilled axially and fitted with a rod of 1.6mm clear perspex for the LED to shine through. Each part had to be machined precisely in all dimensions. It was a royal pain and at the end I vowed never to do such a thing again. |
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| EC8010 |
| As promised; photo of removable SME headshell in socket. |
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| percy |
| quote: | Originally posted by EC8010
You can make a headshell out of 1 1/2" aluminium angle (1/8" thick). I made this with the assistance of a Black & Decker power drill in a stand, a junior hacksaw, and a few files.
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http://www.diyaudio.com/forums/attachment.php?s=&postid=979709&stamp=1155196469
EC8010, would you by any chance know how much this headshell weights ? just the headshell without all the mounting hardware and leads and stuff.
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| bulgin |
Hi Everyone
The deed is done. I have a couple of arms (some new & still boxed) but all these use their own type headshell or wand which are either unobtainable or very expensive. My Micro arms have only really one headshell left in good condition. I therefore took the plunge and just finished making a replacement curved wand for it, plus all the fittings, including an addition to the armweight.
SME-type headshells are no problem to obtain and this arm can now take these shell.
All is ready for anodising tomorrow (sorry later today) and rewire. Looks very good, I must say but the proof of success is in using it.
Don't laugh, but the curved wand has been made from one of the landing sleds of a r/c helicopter (found last year in a black rubbish bag, sitting on the pavement).
bulgin |
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| EC8010 |
I'd weigh it on the kitchen scales I got as a Christmas present but the headshell is now on an arm in Hong Kong. You can calculate the mass by knowing that aluminium has a relative density of 2.7 and the headshell was 1/8" thick. |
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