Wednesday, April 25, 2012

The Teflon Paste

When completing an application of Teflon powder try this paste.  Place a small amount of Teflon powder in a bowl. Mix in some isopropyl alcohol to make a paste.

Then apply that paste to the leather or buckskin knuckles. The alcohol evaporates quickly and leaves only the Teflon. Applied this way keeps the Teflon dust down to a minimum.

I have also found that the alcohol allows the Teflon to migrate further into the fibres of the buckskin. After several applications over time, even when the knuckles are brushed, one can see that a certain amount of Teflon remains impregnated in the material of the knuckle. 

Another observation I have with this paste is the fact that at times the paste will shrink the knuckle buckskin a certain amount. This is beneficial when technicians find certain knuckles have gone soft from use, which is the buckskin stretching. The paste can be used in certain circumstances to replace bolstering.  At times, if I am aware that the knuckle materials are soft prior to applying this paste, I will use the 70% isopropyl instead of the usual 91% solution. The added water in the 70% helps to shrink the buckskin making the knuckle hard again.
I would recommend mixing this up in small batches, otherwise the alcohol evaporates before you get a chance to use the mixture and you will have to remix.

I cannot claim the original as my own. This came to me a few years ago from Jerry Groot RPT who lives in Grand Rapids, Michigan. Thanks Jerry!

Here is a set of photos showing the Teflon paste.

Teflon Paste 

Williams Piano Company

Williams Piano Company of Oshawa was another leading Canadian piano company that developed a rather unique response to compete with the new Heintzman plate design.
Robert Sugden Williams had a new plate designed called New Scale Williams. This involved a new plate flange similar in look to the Heintzman Patented Agraffe bridge flange.
In the New Scale Williams design holes were not drilled into the flange itself but an agraffe was set into the backside of the flange, in what I have called a reverse agraffe assembly.  
Recently I came across one of these instruments and took a series of photos of this particular set-up.
I can imagine if one of these agraffes ever broke it would be impossible to repair without removing the entire plate.

Please note that recently Google has changed the Picasa web albums that I use here on this blog. If anyone experiences problems with viewing the photos let me know and I will assist in solving the problem.

The link below is the photo set for the New Scale Williams plate design. 

Saturday, February 18, 2012

Heintzman & Co of Canada

Finishing a piano scale design on his kitchen table in 1860, this drawing is often thought to be the one that launched his career in the piano building business. By 1866 enough capital had been raised for Theodore Heintzman to open his own factory.

By 1879 more than 1,000 instruments had been manufactured, and this factory passed the 2,000 mark in 1884 some five years later.

In 1896 Theodore Heintzman completed a drawing of a particular plate design that would catapult the Heintzman Piano Co to the top of the Canadian piano market, where this company would remain for more than 100 years.  
This plate design incorporated what is called the Patented Agraffe Bridge. This bridge takes the place of the pressure bar assembly usually found in upright pianos. In the grand piano, this bridge takes the place of the v-bar design which the strings pass under. 

The bridge has holes drilled at 7-10 degrees angle for bearing purposes. Each piece of treble piano wire must pass through one of the holes and then be attached at both the hitch pin and the tuning pin. 

This particular piano plate design causes the Canadian Heintzman piano to be one of the most difficult pianos to re-string. In the upright version, one can tilt the piano over onto a tilting piano truck which will help to find the hole for each piece of wire. Another way to accomplish restringing of an upright with this bridge is to have a mirror placed underneath the working area and a lamp on top to shine light into the holes.

In the grand version of this piano the flange with the holes cannot be seen at all from either the tuning pin side or the sounding board side of the plate. Also, because the grand piano pin block must be supported from underneath when driving the pins in, usually a small mirror is used or the job is done by feel only. 

 One of the benefits of having this type of design is to keep each piano string of the unison equal distance away from each other for quality sound and for equal hammer wear over the entire surface of the hammer strike point. 

Another benefit of this type of design is to prevent bridge roll. Bridge roll syndrome is when the treble bridge attached to the piano sounding board is slowly dragged, in a lengthwise rolling motion, towards the player over years being under tremendous tension. This is often one of the contributing factors in the sounding board deterioration of pianos. 
Here are some photos of the Heintzman & Co Patented Agraffe Bridge. Both the upright version and the grand version of this design are shown here.