On making original style Wiper Blades.
Firstly I want to say that I don't think the other forum "ORIGINAL GT40s" is the correct place for this kind of post, nor a few other threads recently posted on there.
Anyhoo I am posting my work here ....
Some views on refreshing these wipers to start with :
They are practically useless and just "concours" snake oil for judges at car shows, and by comparing asking prices to actual value - honey pots for dealers in black market parts or for kit-car builders like me deluding myself about originality.
The patent raised in 1963 by Trico Folberth Ltd for these wiper improvements specified "either die-cast metal or injection moulded plastic for the fasteners"
Although similar in appearance, some folks now call them "Speedblades" but the fully metal SB's used a simpler blade refill arrangement.
The original plastic parts are not white nylon and are actually formed in a pale grey lesser plastic. They only appear white probably caused by sun bleaching or oxidation.
There are major issues with these wipers - and probably the reason for their rarity is their early mechanical failure, being not fit for purpose and being binned early by dealers.
Reason ? material, on some sections the actual wall thickness of the so called fasteners is a very thin and brittle plastic. Or about 30 thou. which is easily molicated by a temperamental Lucas wiper motor and a sticky screen.
Four of the two-piece plastic parts connecting to the refill spine also have stainless angle inserts in them and also with patent Latch Locks at both ends. These inserts are also weakening the parts by reducing cross sectional mass of the plastic mouldings.
All of the examples of these wipers that I have inspected have linear stress cracks on every plastic piece in line with the wire and inserts and many with complete break failures which probably started propagating on day one of their use.
The die-cast versions mentioned in the patent registration were probably not considered due to reaction with the stainless wire, brittleness or calculated as too heavy. Also assembly of the two-parts of each fastener around the inserts and wires might perhaps be more involved than just hot ironing plastic through stud versions.
We have some genuine unused wiper refills for our Tricos and I think that we are half way there with the idea of making four working units for us, if we get more refills we will think about more, however for the rest of the frames I will be making parts using titanium wire and bar-stock and maybe trialling Duratron / Torlon for the fastener material.