Repairing TR Side Curtains
Neville Turbit - Dec 2015

 

I have just completed window replacement on my side curtains, and thought it might be worth sharing the experience.  Before you read any further, if you are after originality, you can stop reading now.  I made the side curtains up using a different approach to the originals.  I built a frame around the forward window.

I had to do two sets of side curtains in fact.  I have one set for the hood, and have just finished doing up a hardtop.  Unfortunately the side curtains for the hood did not fit in the hole for the hardtop curtains.  Fortunately I had an old set of side curtains stored in the roof.  They had no windows and had not been on a car for about 45 years.  I adjusted those to fit the hardtop.

The side curtains were off my first TR which went to the wreckers around 1970 after an unfortunate meeting with a guy who had a license for all of one week.  It was obtained in Byrock.  In 2006 it had grown to a town of 90 people so I am not sure of the population in 1970.  This guy flew to Sydney and borrowed his brother’s car.  He was confronted with a new concept.  Traffic lights.  No problem. Turn right.  Unfortunately he was confronted by another new concept.  Oncoming traffic.  So endeth the first TR.

Up to now I had windows with two pieces of 2.5mm Perspex jammed in the channel.  It was a two handed job to make them slide, and they scratched one another over time.  At one stage, I did have some thinner Perspex which I used for the forward fixed window. It was about 1.5mm and jammed in between the side curtain frame and the Bailey Channel (I didn’t know the channel for the glass to slide was called Bailey Channel until I posted a question on the club forum).  Unfortunately it decided to leave home at speed and shattered when gravity propelled it towards terra firma. 

I did some serious research before I started (read Google), and found I should not be using Perspex for the thin forward fixed window.  I should be using a similar material called PETG which comes in anything from 0.75mm thickness to 1.5mm.  I bought a sheet which was more than enough for two side curtains, but not enough for four as I later found out, from Australian Plastic Fabricators in Silverwater.  Total cost $20.  I also bought 2.5mm clear Acrylic for the same price.  This is used for the rear sliding window.

The PETG is very flexible.  I rolled it up into a 15cm roll to bring it home. It was never going to stay in the frame without some sort of attachment.  I thought of gluing it in place but figured that was a bit too permanent.  One day I will need to replace it and it will likely do damage to remove the glued in sections.  I had also heard someone suggest Velcro to attach to the flap on the forward edge.  That seemed a bit complicated to get Velcro sown onto the flap so I came up with another solution.

Went to the local hardware store and bought some aluminium.  There were three sizes.

·         Angle 12mm x 12mm x 1.5mm

·         Strip 10mm x 3mm

·         Strip 12mm x 3mm

I was able to start making a template for the windows by using the existing windows.  I made it from cardboard as the existing windows were not a great fit.  I traced the window opening onto the cardboard then overlaid the Perspex on the drawing.  It became evident where I should add a little here, and remove a little there to make a better fit.  After cutting out the windows in cardboard, I was able to trim them to fit the frame.

Perspex is relatively easy to cut with a jigsaw provided you take your time and use a fine tooth blade. 

PETG is a whole different ball game.  You cannot cut it with a jigsaw as it shatters.  You need to use a router.  I found the best solution was to put a piece of corrugated cardboard over a piece of melamine I had lying around.  I use that as a bed to hold down the PETG. 

I used two clamps to hold down the sheet, then two clamps to hold down a straight edge (actually used the aluminium angle) as a guide for the router.

In the picture you can see a piece of Perspex with a cross on it in the foreground.  This is a spacer I made which gives me the exact distance between the guide and the cut.  Makes it easy to set up the guide bar.  Another tip is to put the guide on the window side of the cut.  It means you cannot inadvertently cut inside the marked line. The precision of my manual skills is legendary.  I am the sort of person who measures something twice to avoid error, and still comes up with three answers.

So with the fixed window cut to size, it is attached to the side curtain. Top and bottom go between the outside frame of the side curtain, and the Bailey Channel.  You might need to hand sand to fit, but don’t worry if there is a slight bow.  That can be fixed.  It is taken up when the frame is fitted.

The front edge of the window fits behind the flap that should be on the front of the side curtain window opening.  Traditionally the window was sowed into the flap but this will not work with PETG.  I dread to think what would happen if you attacked PETG with a sewing machine.  The nearest thing I can think of is standing beside a Formula 1 collision and ducking the flying shards of carbon fibre.

I cut a strip of the 12mm x 3mm aluminium to fit inside the window.  I drilled holes along the strip, then through the window and the vinyl. 

A trip to the local boat shop turned out to be more expensive than anticipated.  I bought 5/32” x ¾”countersunk screws, washers, cup washers and dome nuts.  Stainless steel of course.  Cost the best part of $100 but that was for 4 side screens.

I put a cup washer on the vinyl side, then pushed the screw through the vinyl, window and aluminium.  A dome nut is on the inside.  The window is effectively sandwiched between aluminium strip and vinyl. Not only that, it is held rigid by the aluminium strip.

On the back edge of the fixed window, I used a piece of aluminium angle cut to size.  It sat on the inside, with the angle pointing out from the car.  On the outside, I put a piece of 10mm x 3mm aluminium strip to sandwich the window.  Countersink the screws on the inside of the angle piece, and put washers and dome nuts on the outside against the strip.  The inside dimensions of the angle are close to the 10mm strip.

 

I had thought of cutting down the angle so it was flush with the strip rather than have a section of the angle pointing out from the car, still visible.  My hacksawing skills warned me against cutting with a hacksaw.  I tried a router to trim down the angle and it resembled a representation of a mountain range.  In the end I thought “WTF.  It looks good as it is”.

The sliding window is marked up the same way.  Trace the opening, then overlay with the old window.  Mark out the old window and adjust the dimensions where it may not be a good fit.  Of course if the old window is a perfect fit, no need to mark out the opening.  You can cut out the sliding window using a jigsaw.

One tip on this step.  Make sure the overlap of the two windows is about 50mm.  I will mention why later in the article.

There is a gap between the fixed and sliding window of about 3mm.  A trip to the local hardware store found a draft seal which is a brush seal (Moroday MWS 8 1-43102).  It has a self-adhesive backing.  I put this over the back aluminium strip.

Now to the handles.  I used some angle I had which was 3mm rather than the 1.5mm angle I had used on the rest of the window.  You could use the 1.5mm but I had the angle in the garage, and thought it would work better.  Never, ever throw anything out.  You never know when you might need it.  Children of course are an exception to this rule. 

Cut a piece about mm long, and also a piece of the 12mm strip the same length.  I drilled two holes in the angle and countersank the flat piece.  Screws go through the strip, the window and the angle.  Dome nuts on the handle side of the sandwich hold it in place. 

The reason for making the overlap 50mm is now obvious.  The handle never has to cross the brush seal.  It is always on the forward side of the seal.  If there was not enough overlap, the handle would be behind the seal.  The backing 12mm plate would slide through the brush seal each time it was opened.  Eventually it would destroy the seal.

The result is a side curtain that looks a bit “industrial” but this is a car that had its origins in the 50’s.  It is not out of place with the look of the TR.  I had one person tell me they thought the windows looked like something off a WWII fighter plane.  It may be non-original but I like to think that that is how it would have been designed if they were not cost constrained in the Triumph design department. 

It works for me.