Brilliant idea, don't change the head geometry change the mounting geometry. This is why you are a bloody good builder and I am a muddler.
DIY Tonearm
- Thread starter audioflyer
- Start date
Brilliant idea, don't change the head geometry change the mounting geometry. This is why you are a bloody good builder and I am a muddler.
Chops54
pfm Member
It certainly would and I did consider that option but whilst most of us here could drill holes from a template not many of us would be able to mill the slots.
Chops54
pfm Member
Slot geometry would mess with the AROs unique and wonderful ability to take the three mount linn carts without any need for crazy setup shenanigans hole geometry would retain that. I believe 12" offset angles are distinctly different from at least one of the mounting holes so the left hole (with the cart facing) will be offset by approx 16 or thereabouts extra degrees, depending on the centre to needle pivot.
An un drilled run would be easy to request from any machine shop with a calculated template. If you are up to making a tonearm, then you are going to be up to drilling two or three holes.
An un drilled run would be easy to request from any machine shop with a calculated template. If you are up to making a tonearm, then you are going to be up to drilling two or three holes.
I will start dumping this data into a Google doc later today. We can use it to track anything decided so far. There are other more complicated tools, but I think we can get most of the way there with a simple editable document.
Some thoughts:
- I would definitely prefer Rega, they have been attached to almost every table in existence, and also I have a P3
- Yup. Perhaps even a fourth hole to accomodate the Rega three point cartridges too.
- This could be achieved by using two nuts and washers on a threaded mount. Clamp the armboard at the appropriate height and bob's your proverbial.
- I think it would be nice to make this a BYO armtube project, with perhaps a couple of off the shelf recommendations.
- Yup
- Regarding a 12" option. This could easily be provided as long as buyers were happy to pay the cost.
- Absolutely! If you find anything suitable as a bearing housing please let me know, I have drawn a complete blank here.
- The weight on a string method seems to be simple enough.
- I like the approach of the Skale. Make an eccentric counterweight and rotate it slightly.
- Nope
- Depends on the armtube used I would guess.
After looking into some costs, machining components in a reasonable quantity is very cheap. I estimate that a kit of parts (bearing cup, bearing mount, headshell) would be around $60-80 (in quantity of 50), which is comfortable less than the bearing itself. This would be machined to high tolerance, polished, and anodized. The problem comes with obtaining prototypes to test that the finished articles would actually work. Using eMachineShop, and my crappy headshell design as an example, the price breaks work out like this (price per item):
1: $486
2: $243
5: $101
10: $53
50: $15
500: $6
Removing the finishing stage (polish and anodise) brings the price down to $150 for one, and $30 for five (down to $4 each for 500), which might be acceptable for prototypes. I have not looked into other suppliers at all yet.
YNWOAN
100% Analogue
I think an element of reality check is in order - it's really very unlikely that 500 takers will be found (or even 100). Naim themselves only made batches of 10 or so at a time!
Changing arm length requires headshell offset angle to be changed.
You can't just randomly cobble arm elements together and expect it to not to gave a sonic impact.
Changing arm length requires headshell offset angle to be changed.
You can't just randomly cobble arm elements together and expect it to not to gave a sonic impact.
Chops54
pfm Member
Yup, I think we'd be doing well if twenty of us took up the challenge.
orangeart
KJF Audio Ltd.
TBH I'm not that bothered about the anodizing and polishing so long as it works. Anodizing at home for these small parts is fairly easy, we could pitch in par the stuff and one of us could do it. It seem massively cheaper done with just the precision machining. I'm sure we could get cheaper quotes anyway, e-machine shop are a little expensive, problem is once you've designed the stuff in their software you're a little locked in.
Getting more than 10 in the DIY room may be difficult, opening it up to the audio room (once plans were complete!) may push those numbers higher. Most of the DIY'ers from this room seem to have gone over to DIY audio nowadays so maybe starting a thread there might reap more rewards? They are well used to GB's, have a good pool of knowledge, and have a huge audience. It would be nice to keep it PFM thought if possible.
For my two penneth i'd rather have rega mount as my other arm's a rega.
There's not much in this GB that I can really help with, I'm happy to do distribution as I did with the hackernap and diode GB's or even assembly if need be. I guess pinning down a design and getting complete costings are more important at this stage.
Stefan
Getting more than 10 in the DIY room may be difficult, opening it up to the audio room (once plans were complete!) may push those numbers higher. Most of the DIY'ers from this room seem to have gone over to DIY audio nowadays so maybe starting a thread there might reap more rewards? They are well used to GB's, have a good pool of knowledge, and have a huge audience. It would be nice to keep it PFM thought if possible.
For my two penneth i'd rather have rega mount as my other arm's a rega.
There's not much in this GB that I can really help with, I'm happy to do distribution as I did with the hackernap and diode GB's or even assembly if need be. I guess pinning down a design and getting complete costings are more important at this stage.
Stefan
orangeart
KJF Audio Ltd.
Probably teaching folk to suck eggs but it's not been mentioned yet. The headshell needs to provide for the stylus to be dead centre to the amp/pivot, one way or the other and the azimuth will be pulled from perpendicular, this will change as the drag on the stylus changes and as the arm track record warps in a unipivot design.
Stefan
Stefan
audioflyer
No going back once you heard a ceramic cartridge
Found one of my cad files as a image on my memory stick.
Sharif
Sharif
Chops54
pfm Member
I'm not too bothered about the anodising or polishing either Stefan. You should see my 12 inch arm lol. It's rough but it works
I think the headshell is the issue and as I was already in discussion with a local machinist about doing some rather simpler head shells for another project of mine I think I'll go over and see him on Friday and have a chat.
A thought did occur to me, for those that want Linn geometry what about using a headshell from a busted Linn Basic Plus or an Akito even if you can find one? I've seen a few for sale on ePay.
I think the headshell is the issue and as I was already in discussion with a local machinist about doing some rather simpler head shells for another project of mine I think I'll go over and see him on Friday and have a chat.
A thought did occur to me, for those that want Linn geometry what about using a headshell from a busted Linn Basic Plus or an Akito even if you can find one? I've seen a few for sale on ePay.
I have been playing around copying the Ekos headshell. It looks like this at the moment (unfinished):
https://www.dropbox.com/s/yrm0jbm7rc5tt8c/3d headshell.jpg
https://www.dropbox.com/s/yrm0jbm7rc5tt8c/3d headshell.jpg
John Channing
fruit box forever
I only added the 100 and 500 quantities for some contrast
I agree, there won't be 500 customers, but even with 10 firm buyers, it might be worth getting 50 made as people will make mistakes, modifications etc. and if the tonearm works well there will be other buyers.
I also think, if you look at the second hand price of an Aro, which seems to have crept ever higher over the last few years (now well north of £1000), there is a reasonable sized DIY market if you can put something together for say, £100.
