Member
Joined 2019
Hi! Greetings to all from a new member.
Some links related to my DIY turntable - TTT - utilizing a floating tangential tonearm after the idea/license of Nikolay Ivanov.
The TTT Vernissage clip:
YouTube
The first TTT development report:
YouTube
The "TTT Vernissage" series, all recordings made with TTT:
YouTube
I will be very glad to discuss with you on any issue related to my construction.
Some links related to my DIY turntable - TTT - utilizing a floating tangential tonearm after the idea/license of Nikolay Ivanov.
The TTT Vernissage clip:
YouTube
The first TTT development report:
YouTube
The "TTT Vernissage" series, all recordings made with TTT:
YouTube
I will be very glad to discuss with you on any issue related to my construction.
Member
Joined 2019
Member
Joined 2019
First of all, a small magnet adjacent to a steel bar will increase friction more than you want.
2nd, it is not a matter how light the arm is, it is the matter of its effective mass. The resonance frequency of your arm can be very high.
3rd, arm floating on water may still have more friction than you expect.
4th, a floating arm may have too much of movements in vertical plane especially the total mass of your arm is very light.
2nd, it is not a matter how light the arm is, it is the matter of its effective mass. The resonance frequency of your arm can be very high.
3rd, arm floating on water may still have more friction than you expect.
4th, a floating arm may have too much of movements in vertical plane especially the total mass of your arm is very light.
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Member
Joined 2019
May I ask which polystyrene?
One common one is white, made from beads. It's called expanded bead polystyrene (EBPS) and is also known as popcorn insulation. This is not a closed cell product and will absorb water over time.
The other common one is blue or pink in colour, and is not made from beads. It is an extruded product and is closed cell. This is the product you want as it resists absorbing water. It is known as XPS. Also referred to as RoofMate in North America.
Make sure you have the right one or it will lead to problems over time.
Nice project by the way.
One common one is white, made from beads. It's called expanded bead polystyrene (EBPS) and is also known as popcorn insulation. This is not a closed cell product and will absorb water over time.
The other common one is blue or pink in colour, and is not made from beads. It is an extruded product and is closed cell. This is the product you want as it resists absorbing water. It is known as XPS. Also referred to as RoofMate in North America.
Make sure you have the right one or it will lead to problems over time.
Nice project by the way.
Member
Joined 2019
- First of all, a small magnet adjacent to a steel bar will increase friction more than you want.
o The distance from the steel bar is adjustable, as declared in the 'TTT Vernissage' clip, 6:04. The friction "I want" is below 20 dyn and will be achieved in the future by use of higher quality bearings loaded by about 2 p force.
- 2nd, it is not a matter how light the arm is, it is the matter of its effective mass. The resonance frequency of your arm can be very high.
o It IS a matter how light the arm is. The effective tonearm mass is also a matter. In my case the effective mass is about 14 g. The resonance frequency is 11.5 Hz. Not very distant from the recommended optimal values.
- 3rd, arm floating on water may still have more friction than you expect.
o I do not 'expect' it, I have measured it. The friction is a function of the float speed and as low as 1-2 dyn for the playing tonearm speeds (less than 0.1 mm/s). The main friction source is that of the leading wheels.
- 4th, a floating arm may have too much of movements in vertical plane especially the total mass of your arm is very light.
o Water is a very good damper of any vertical movements and/or vibrations. My digital microscope videos do not indicate valuable vertical movements.
o The distance from the steel bar is adjustable, as declared in the 'TTT Vernissage' clip, 6:04. The friction "I want" is below 20 dyn and will be achieved in the future by use of higher quality bearings loaded by about 2 p force.
- 2nd, it is not a matter how light the arm is, it is the matter of its effective mass. The resonance frequency of your arm can be very high.
o It IS a matter how light the arm is. The effective tonearm mass is also a matter. In my case the effective mass is about 14 g. The resonance frequency is 11.5 Hz. Not very distant from the recommended optimal values.
- 3rd, arm floating on water may still have more friction than you expect.
o I do not 'expect' it, I have measured it. The friction is a function of the float speed and as low as 1-2 dyn for the playing tonearm speeds (less than 0.1 mm/s). The main friction source is that of the leading wheels.
- 4th, a floating arm may have too much of movements in vertical plane especially the total mass of your arm is very light.
o Water is a very good damper of any vertical movements and/or vibrations. My digital microscope videos do not indicate valuable vertical movements.
Member
Joined 2019
- It seems to me that changing water level is the only way to adjust VTA.
o You can also adjust the height of the "aquarium" with respect to the platter. Keeping the water level constant within 1 mm is important for the predictable work of the lift mechanism. During these warm summer days the daily loss of water is about 20-30 ml. I am planning a level indication system, providing a LED light signal for too-low , normal and too-high water levels. In a future development, this system will activate a water supply mechanism for automatic correction of the water level.
o You can also adjust the height of the "aquarium" with respect to the platter. Keeping the water level constant within 1 mm is important for the predictable work of the lift mechanism. During these warm summer days the daily loss of water is about 20-30 ml. I am planning a level indication system, providing a LED light signal for too-low , normal and too-high water levels. In a future development, this system will activate a water supply mechanism for automatic correction of the water level.
Member
Joined 2019
Panayotis,
I am thinking a liquid coating for the EBPS and essentially 'close' the cells. I will have to investigate as one has to be careful or the polystyrene will react to it. I know some epoxy resins are safe but apparently not all? I'm pretty sure a polyester resin, like they use for fiberglass is safe.
I am thinking a liquid coating for the EBPS and essentially 'close' the cells. I will have to investigate as one has to be careful or the polystyrene will react to it. I know some epoxy resins are safe but apparently not all? I'm pretty sure a polyester resin, like they use for fiberglass is safe.
Member
Joined 2019
Member
Joined 2019
Member
Joined 2019
For super10018
- 4th, a floating arm may have too much of movements in vertical plane especially the total mass of your arm is very light.
o The clip below is another answer. The two movements refer to exactly the same initial region of the LP.
Boat Movements.mp4 - Google Drive
- 4th, a floating arm may have too much of movements in vertical plane especially the total mass of your arm is very light.
o The clip below is another answer. The two movements refer to exactly the same initial region of the LP.
Boat Movements.mp4 - Google Drive
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Member
Joined 2019