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
dougdeacon
I just ordered the etching creme. I reread the thread and found it, many thanks.
Regarding the splicing tape, Is there any splicing tape available that matches the colour of the tape?
Splicing tape is always white so engineers can more easily find the splice afterwards.

They sure won't have any trouble seeing that splice come around on a clear belt. ;-)

Frank_sm,

just to clarify a little. The "metal" side has always been the side in contact with the platter and capstan. This surface required a certain tension, no more and no less, to perform at its peak. Over the course of a few weeks or months the metal would have worn sufficiently to cause slippage. So many of us would just make a new belt and sit in wonder at the improvement of a fresh belt. Little did we know that we should have gone in the other direction. But, had we found that Doug and Paul wouldn't have had anything to tinker with. With Paul's new trick there is no more slow erosion of the metal surface and it seems that this textured surface is superior to the old metal surface in every way.

Someone else may have a better method but I'll share mine. I use a plastic pan that is maybe 14x12x8 to contain the etching creme and wear heavy pvc gloves (Home Depot). Remember, it is the side the tape wants to curl to. Since I'm right handed, I start with one end of the tape in my left hand. I dab on the creme using a 3/16" artist's brush to get the end. Then I load the brush, hold it against the tape and pull the tape past the brush with my left hand leaving the treated tape in the pan. You can see the metal vanishing while you're working. Then I take the pan, brush and gloves outside to the faucet to rinse. It really is easy, using a little caution, and takes only a few minutes. The curl is still there, but you won't have any trouble telling which is the smooth side and which is the textured side.
For those looking for another color in splicing tape I got some Professional Archive splicing tape for 1" and 2" recording tape from US Recording and it is a nice shade of blue and works very well.
Here's another source for splicing tape:
http://www.tapecenter.com/splictapinby1.html
a little cheaper, for 100' vs. 82' on the other site I gave you above. I don't know if one is better than the other..

I've never seen splicing tape in anything but white... but I haven't seen everything...

Frank, to answer your question about stripping. It's done on the side where the silver is: if you do it on the other side, nothing will happen. That side then becomes the one in contact with the pulley and the platter, the "inside" side, as you assumed.
Hello Doug you sent me a link to McCormicks for mylar streamers a good while back. What i am using does not appear to have a silver metallic coating. I ordered black, i'm getting great use from it. Do you think i'm using the wrong mylar streamer?
Many thanks for the great tweak and have a good one.