That's certainly frustrating Paul!
I guess/hope there will be some sources somewhere that can supply though.
For the rails, weight doesn't matter and certainly a pair of rods, carefully assembled could work well.
I glued my stainless steel ones to a carbon plate, paying careful attention to flatness.
Anodised aluminium is easily hard enough to work satisfactorily, i have run many test and use hours and seen no marking at all.
One can obtain hard anodised aluminium and special coatings like teflon as well, and that is one route i have yet to try. i have handled some examples and it seems likely the coatings fill some of the micro sized dips.
I found a local supplier who would coat all the arm parts i need for £100, but i haven't made any yet!
I recommend you build a carriage with commercially available anodised angle and get a feel of that set up.
Materials in contact interact depending on material types and the forces between them may be more important than simple hardness and flatness.
Good luck
M
I guess/hope there will be some sources somewhere that can supply though.
For the rails, weight doesn't matter and certainly a pair of rods, carefully assembled could work well.
I glued my stainless steel ones to a carbon plate, paying careful attention to flatness.
Anodised aluminium is easily hard enough to work satisfactorily, i have run many test and use hours and seen no marking at all.
One can obtain hard anodised aluminium and special coatings like teflon as well, and that is one route i have yet to try. i have handled some examples and it seems likely the coatings fill some of the micro sized dips.
I found a local supplier who would coat all the arm parts i need for £100, but i haven't made any yet!
I recommend you build a carriage with commercially available anodised angle and get a feel of that set up.
Materials in contact interact depending on material types and the forces between them may be more important than simple hardness and flatness.
Good luck
M
TwinArm - a passive servo linear? #5480 to #5525
Another step of my box kicker method - some more due infos.
c
Another step of my box kicker method - some more due infos.
c
Attachments
Last edited:
Paul, whilst you're gathering thoughts i would like to introduce you to 4 other areas you might consider (or discard!!)
Wiring, leverage, levelling and vertical orientation.
There have been a number of explorations on thread here that are of interest.
1. Wiring is probably an easy one, many folk, including me start out with something available and rapidly find springy wiring is a significant failure.
I followed Niffy's advice and use two spiralled cores per pole all wrapped in a sleeve of three cores of screen, so 11 cores in total of fine enameled magnet wire, you may have found the references already. With this there is no perceptible effect from the wiring.
2. The much used wand and carriage asks the stylus side force to move the carriage on a long lever, like pushing a car to and fro with a pole out the side, rather than pushing it on axis, Radial arms where the carriage is above the stylus remove this lever.
3. Levelling your arm will be critical, way more critical than any bubble will show you, and so also stability of your TT/carriage base set up in level will be important. so, locking the arm in vertical orientation (balanced level, stylus off the record) you can adjust for level travel.
4. On a wand the cartridge will change its vertical orientation to the record constantly with factors such as record thickness and warp. Carlo resolved this with several of his RTA's with a solution for leverage at the same time. In my opinion these are well worth a study.
M
Wiring, leverage, levelling and vertical orientation.
There have been a number of explorations on thread here that are of interest.
1. Wiring is probably an easy one, many folk, including me start out with something available and rapidly find springy wiring is a significant failure.
I followed Niffy's advice and use two spiralled cores per pole all wrapped in a sleeve of three cores of screen, so 11 cores in total of fine enameled magnet wire, you may have found the references already. With this there is no perceptible effect from the wiring.
2. The much used wand and carriage asks the stylus side force to move the carriage on a long lever, like pushing a car to and fro with a pole out the side, rather than pushing it on axis, Radial arms where the carriage is above the stylus remove this lever.
3. Levelling your arm will be critical, way more critical than any bubble will show you, and so also stability of your TT/carriage base set up in level will be important. so, locking the arm in vertical orientation (balanced level, stylus off the record) you can adjust for level travel.
4. On a wand the cartridge will change its vertical orientation to the record constantly with factors such as record thickness and warp. Carlo resolved this with several of his RTA's with a solution for leverage at the same time. In my opinion these are well worth a study.
M
Hi Andrey, Sorry for the late reply I have been away. I don't have a dust cover over my TT and I do wipe the rails occasionally with a cotton bud. I haven't had an issue with dirt on the rails causing problems. Dressing of the wiring harness is more important and if not done correctly can cause the stylus to skip.
cheers Warren
Hi Paul, I'm a bit late to this conversation. I think building the original design is a good idea as it works extremely well. My first build was the version 2 with dual glass rods. If I was doing this again I would use linear shaft it's inexpensive and if you buy good quality also straight.
I used off the shelf ball race bearings. Removed the dust covers and removed the grease. If you spend a bit more you can buy fishing reel bearings that use dry race, these are sold for casting competition.
Hi,
@Mike56 "
1. Wiring is probably an easy one, many folk, including me start out with something available and rapidly find springy wiring is a significant failure.
I followed Niffy's advice and use two spiralled cores per pole all wrapped in a sleeve of three cores of screen, so 11 cores in total of fine enameled magnet wire, you may have found the references already. With this there is no perceptible effect from the wiring."
That sounds as quite a lot of copper and stiff wiring for such a small wire... But then I have to admit that I quite don´t understand the recipe in fullness.
Do You have a sketch or pics of the construction or more info about it?
Thanks
Calvin
@Mike56 "
1. Wiring is probably an easy one, many folk, including me start out with something available and rapidly find springy wiring is a significant failure.
I followed Niffy's advice and use two spiralled cores per pole all wrapped in a sleeve of three cores of screen, so 11 cores in total of fine enameled magnet wire, you may have found the references already. With this there is no perceptible effect from the wiring."
That sounds as quite a lot of copper and stiff wiring for such a small wire... But then I have to admit that I quite don´t understand the recipe in fullness.
Do You have a sketch or pics of the construction or more info about it?
Thanks
Calvin
And 5291 gives a picture. To give a feel of the flexibility, this is about 175mm long in my set up and moving the connector end from one side of a record width to the other will not "pull" the carriage, despite the low friction. There is enough form in the group to retain the spiral shown. There is no perceivable hum now with shielding as described.
A satisfactory solution for a few cents of wire and some simple work.
M
I did then make a capacitance selector set for my preamp and measured the frequency response to choose an optimum, but that's a different story!
A satisfactory solution for a few cents of wire and some simple work.
M
I did then make a capacitance selector set for my preamp and measured the frequency response to choose an optimum, but that's a different story!