Wow, I just acid etched a belt from the ones Thom made me for my Serac and there is a nice improvement in dynamics. Great tweak, I'll be making up extra belts in the next few weeks.
Upgrade for users of 1/2" mylar belt
This thread will be of interest to Galibier, Redpoint and Teres belt drive TT owners, or anyone using or thinking of using a drive belt made from 1/2" mylar. The belt material of choice on these tables for several years has been the silver holographic mylar streamers from sources linked on the Teres and Galibier websites. This outperforms everything else we've tried but like anything it's not perfect - and we've now found something better.
One of the silver holographic mylar's assets can also become a liability. That metallic layer, when new, gives the belt exceptional "grip" on the platter and motor capstan. Minimal slippage on transients is one reason the material works so well. Unfortunately, that layer can wear over time, leaving a silvery gray residue and allowing performance to deteriorate. The only solution has been a good cleaning and a new belt. No big deal, but if there was a better or more stable belt Paul and I wanted to find it.
I'll spare you a recounting of our many experiments and jump to the good news: thanks to (yet another) brainstorm by my resident genius/partner, we've developed a belt that both performs better and lasts longer. I've held off posting until we were sure, but after 4 months of steady use Paul’s idea is still working perfectly. The only negative is that making this new belt takes an hour or more of work spread over two days, but to us it's worth the effort.
HOW TO MAKE ONE
1. Cut a length of the silver holographic mylar tape sufficient for your TT, plus 3-4" extra.
2. Remove the silver metallic coating off the backside of the mylar. Paul used an acid etching cream popular with stained glass hobbyists to dissolve the metal - safe, quick and easy (use skin and eye protection).
3. Rinse thoroughly under running water, inspect to make sure you got all the silver off, wipe and hang to dry overnight.
4. Splice as normal to make a TT belt, making sure you tape on the OUTSIDE (which will be smoother than the now bare inside).
5. As always, the best splicing technique is to overlap the ends and cut on a 30-40 degree angle. Apply 1” video splicing tape (*not* tabs) across the belt at the *same* angle and trim away the excess.
WHY IT PERFORMS BETTER
Unlike any plain mylar ribbon you could easily buy, the silver holographic streamer has an ultra fine texture embossed on the back side of the *mylar* during manufacturing (*before* the metallic backing is applied). Once the silver layer is applied you can't see this texture, but that's what diffracts light like a million tiny prisms to produce the shimmery rainbow effect. Stripping the metal backing away exposes this texture, which becomes the contact surface of your new belt.
Paul realized this texture must exist and then hypothesized that using it for the working side of a TT belt might provide more “grip” on the platter rim and motor capstan than either plain mylar (which is extremely smooth) or the metallic backing. He was right. This belt produces more lifelike dynamics, both macro- and micro-, than even a brand new silver holographic belt - which heretofore was the best.
WHY IT LASTS LONGER
Removing the metallic backing exposes bare mylar, which is much sturdier than that fine layer of metal. Under normal use and assuming no accidents, one of these belts should last many, many months, perhaps years, while delivering consistent performance. Ours is going into its fifth month with few visible and no audible signs of wear.
Different motor capstan materials might interact with this belt differently, but I urge anyone with a compatible table to give this a try. Like all our favorite little tweaks, we'd find it hard to go back.
A FEW TIPS
1. Clean any silver/grey residue from your old belt off the motor capstan and platter before mounting the new belt.
2. As many of us have learned, the more inelastic the belt, the more critical motor leveling becomes. That is truer than ever with this new belt. Getting the motor set just right is touchy. Take care that your new belt is riding level in the center of the capstan before you start to play. You don't want it sliding up or down and mangling itself.
3. Motor distancing is also more critical than ever. Since this belt will not slip *or* stretch, tension must be perfect. The right amount is just shy of the tension that would tilt the motor off its feet.
4. Depending on your climate, the belt can build up static potential during use. Not enough to spark, but more than enough to attract airborne dust. I dust the belt's inside with my CF brush after each side before stopping the platter.
5. With this or any belt, always start your platter spinning with a helping push. Just pressing the motor's ON button creates lots of belt-wearing friction as the rapidly spinning motor tries to drag that heavy platter up to speed.
It all sounds like a pain, and it is! But the sonic and longevity results are worth the effort.
Cheers,
Doug
One of the silver holographic mylar's assets can also become a liability. That metallic layer, when new, gives the belt exceptional "grip" on the platter and motor capstan. Minimal slippage on transients is one reason the material works so well. Unfortunately, that layer can wear over time, leaving a silvery gray residue and allowing performance to deteriorate. The only solution has been a good cleaning and a new belt. No big deal, but if there was a better or more stable belt Paul and I wanted to find it.
I'll spare you a recounting of our many experiments and jump to the good news: thanks to (yet another) brainstorm by my resident genius/partner, we've developed a belt that both performs better and lasts longer. I've held off posting until we were sure, but after 4 months of steady use Paul’s idea is still working perfectly. The only negative is that making this new belt takes an hour or more of work spread over two days, but to us it's worth the effort.
HOW TO MAKE ONE
1. Cut a length of the silver holographic mylar tape sufficient for your TT, plus 3-4" extra.
2. Remove the silver metallic coating off the backside of the mylar. Paul used an acid etching cream popular with stained glass hobbyists to dissolve the metal - safe, quick and easy (use skin and eye protection).
3. Rinse thoroughly under running water, inspect to make sure you got all the silver off, wipe and hang to dry overnight.
4. Splice as normal to make a TT belt, making sure you tape on the OUTSIDE (which will be smoother than the now bare inside).
5. As always, the best splicing technique is to overlap the ends and cut on a 30-40 degree angle. Apply 1” video splicing tape (*not* tabs) across the belt at the *same* angle and trim away the excess.
WHY IT PERFORMS BETTER
Unlike any plain mylar ribbon you could easily buy, the silver holographic streamer has an ultra fine texture embossed on the back side of the *mylar* during manufacturing (*before* the metallic backing is applied). Once the silver layer is applied you can't see this texture, but that's what diffracts light like a million tiny prisms to produce the shimmery rainbow effect. Stripping the metal backing away exposes this texture, which becomes the contact surface of your new belt.
Paul realized this texture must exist and then hypothesized that using it for the working side of a TT belt might provide more “grip” on the platter rim and motor capstan than either plain mylar (which is extremely smooth) or the metallic backing. He was right. This belt produces more lifelike dynamics, both macro- and micro-, than even a brand new silver holographic belt - which heretofore was the best.
WHY IT LASTS LONGER
Removing the metallic backing exposes bare mylar, which is much sturdier than that fine layer of metal. Under normal use and assuming no accidents, one of these belts should last many, many months, perhaps years, while delivering consistent performance. Ours is going into its fifth month with few visible and no audible signs of wear.
Different motor capstan materials might interact with this belt differently, but I urge anyone with a compatible table to give this a try. Like all our favorite little tweaks, we'd find it hard to go back.
A FEW TIPS
1. Clean any silver/grey residue from your old belt off the motor capstan and platter before mounting the new belt.
2. As many of us have learned, the more inelastic the belt, the more critical motor leveling becomes. That is truer than ever with this new belt. Getting the motor set just right is touchy. Take care that your new belt is riding level in the center of the capstan before you start to play. You don't want it sliding up or down and mangling itself.
3. Motor distancing is also more critical than ever. Since this belt will not slip *or* stretch, tension must be perfect. The right amount is just shy of the tension that would tilt the motor off its feet.
4. Depending on your climate, the belt can build up static potential during use. Not enough to spark, but more than enough to attract airborne dust. I dust the belt's inside with my CF brush after each side before stopping the platter.
5. With this or any belt, always start your platter spinning with a helping push. Just pressing the motor's ON button creates lots of belt-wearing friction as the rapidly spinning motor tries to drag that heavy platter up to speed.
It all sounds like a pain, and it is! But the sonic and longevity results are worth the effort.
Cheers,
Doug
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- 171 posts total
Jp11801, Glad another listener is enjoying the improvement from this little tweak. *** Following up on the capstan topic, Palasr was kind enough to mail me four capstans he's used on his Gavia. This was so I could try one with straight vertical sides, rather than the mildly convex shape supplied by Teres. Three of the four were too large in diameter for the range of my motor controller. The stock Galibier capstan worked however, so we A/B'd with our Teres capstan. On our table, the Teres capstan was the winner, slightly less smearing and better micro-dynamics. My hypothesis is that the brass Galibier capstan's smooth finish may allow more slippage than the slightly (intentionally) coarse finish of the Teres capstan, which is made of some non-metallic material that I can't identify. Kudos to Chris for supplying a great performing material, and a suggestion to Thom and Galibier owners that a less polished capstan might further improve performance. Best of all (I think) would be a straight-sided capstan with the set screw mounting used by Galibier, but made of the material used by Teres. Any takers? |
Hello Doug was hopping you are others may have an answer to your long ago last post. My redpoints drive pulley has worn due to many hours of use. The brass make up has worn in to the friction and sliping of the mylar belt. Im still able to enjoy the TT but sure would like to have something on hand ready when the time comes. The pulley is super glued on so getting the original off will be a task in its self. Hopping all is going well Mike |
Hi Mike. Acetone will dissolve cyanoacrylate adhesives (aka 'Super Glue'). Work with the motor upside-down to keep residue from flowing down the shaft into the bearings. I use Lok-tite. Super Glue seems like overkill to me. I haven't found anyone to make a replacement capstan but perhaps that's because I haven't looked. ;) I presume any machine shop could do it. AFAIK all they'd need would be a lathe, a drill press and a length of bar stock cut from the material of your choice. A local tech school or high school shop might enjoy a little project. |
While I don't use mylar belts I was googling and found this link regarding ultrasonically sealed mylar belts. Maybe it will be of interest. mylar belts |
- 171 posts total