Alex Black's Window cable clamp screw

[gherlt]

Hello,
as Alex at present cannot supply more of his much acclaimed clamp screws and he was encouraging me to source them by myself, so I tried to do.
I bought sets of different M6 screw types, different materials, some with even a hole (length wise) in them, and then tried for myself.
Alex advised to have professional equipment, I can now confirm that with "consumer level" tools it is quite difficult. Even buying professional drills and taps, all more or less broke.
I then came up with a different aproach, I think a smooth one.

So, I went to a professional with a lathe, he is willing to do the work.
He is currently working on a steel screw replicating the Alex Black screw and will come back with an cost estimate for doing 50. I will update here as soon as I get feedback.

Now to my approach to the clamp screw:
The original screw catches the cables by the force of the nut "against" the window glass (with some washers in-between).
Alex Black separates that and uses a grub screw to hold the cable and a nut to fix the assembly to the window glass (less force on the glass).

My approach is a mix between the Lotus and Alex' one. Instead of using a nut, I use a shortened version of Alex' screw (about 10mm long), but the grub screw has a wide head and his length is exactly that needed to hold the cable. And the space between the heads is exactly that needed for window glass and spacers.
I was advised to do this in brass, as it is much easier to manipulate then steel.
The prototype does work quite well, so I would like to ask the more experienced people here what the think about this approach, about doing it in brass. Same question applies to the replication of Alex Black's screw, would it be OK doing it in brass ??

Here some pictures:

These are M8 screws made of brass, threads taken off, interior M4 thread, cross drilled hole for the cable

Shortened to correct length and head flattened to half

with washer placed

pressed on glass from below, wit cable and washers

assembly completed but not screwed down.

[h20hamelan]

Is the force on the cable equil between all contact surfaces?
I am midway restoring an old pedal bike, I have used some newer hard plastic directional plates under the crank. Toyed with a few different options. Though, I know not what would work best here.

[billwill]

It looks to me to be too long and will foul on the metal frame or pulley spaces.

[Craven]

Grade of Stainless is everything when it comes to machining, some grades, 201, will work harden making life difficult. Grade 303 is your best chance in taping the central hole, have a clearance diameter hole other than length of grub screw.
Brass is a machinist dream material.
Personally I think the original arrangement with correct soft copper and fibre washers suitable, using a stainless nut & bolt.

[gherlt]

It looks to me to be too long and will foul on the metal frame or pulley spaces.

It does not. And this screw is not yet perfectly grinded, it is crooked.

This is at the lower plate

This is at the top plate, tight, but still passes with no touches.

[gherlt]

Has anybody one of Alex Black's screw at hand ?

I would like to know the height of the screw head.

[elanner]

Has anybody one of Alex Black's screw at hand ?

I would like to know the height of the screw head.

Is this what you're looking for? About 95 thou. I'm sure 1/10" would be fine.

Nick

[gherlt]

Great, thank you very much Nick !