Richard_Blake
New member
Made a mistake. Got mixed up 'tween cms and inches, cut too much off one arm of the bronze prop shaft A bracket (actually a "V" - no cross-piece). Cursed loudly.
Best solution: shorten the shaft tube by about an inch to bring everything back close enough to the hull (quarter-mounted propellor on a smack hull) and incidentally giving me the clearance for a shaft anode, plus bring the A bracket mounting blocks better over a frame.
That means I have to tap threads further up it (the shaft tube): Whitworth 55 degree, 14 G on a 1.5 inch outside diam. bronze pipe. Totally unavailable here. Nice engineer said he could turn the thread on the pipe for me on his lathe, but it's glassed into the boat. Don't think Edith would enjoy the spinning experience.
SO: if I describe the A-bracket, perhaps someone can tell me who made/makes it. They may be able to help me with tapping equipment.
OR: does anyone have a 1.5 inch whit. 14G steel nut (also of course totally unavailable here) lying about I can beg or buy for undying gratitude, etc.. Then I can do the old trick of the clever diagonal cut in the nut which makes it into a thread cutter.
BORING DESCRIPTION OF A-BRACKET:
It's bronze, of a type formerly often seen. Probably installed new on Edith in around 1985. No maker's name, just the number 205 on the mounting plates. Cast mounting plates roughly 3.5 inches square, four countersunk screw holes for fastening to hull, with a bit sticking out to accept the arm of the A (or V) - this sticking-out bit is wider than the arm, with raised edges like a shallow channel, to positively locate the arm. Holes in channel bit tapped to take bolts through arm. The bronze arms (1 and 1/8th wide by 3/8ths thick) are not drilled when you buy it new, so you can cut it to size (ha,ha!) yourself then drill it . The lump at the lower end of the "V" containing the cutless bearing is in three parts - the middle one of which is integral with the arms; the rounded/slightly pointed section at the propellor end has two large flats so you (or Charles Atlas) can unscrew it with a very big spanner; the forward end has the water lubrication holes in it, and is tapped to screw on to the tube.
Anyone recognize it? Or did half-a-dozen factories all make virtually the same thing?
We in fact have a spare, brand-new and exactly the same, which we saw by chance in a second-hand chandlery and snapped up in case we ever came down hard on a hard place. I would prefer to go on having a spare though, in case we ever come down...... So I'd rather not use it to correct the stupid mistake, when all I need is re-threading (apart from a new brain, that is.).
I now have a great deal of respect for those clever people on this forum who manage to ask for help in no more than two sentences!
By the way, can one get superscript little high and low letters/numbers on internet posting pages in order to efficiently write fractions? What knob do I press?
Help!
Richard
<hr width=100% size=1>LowTech
Best solution: shorten the shaft tube by about an inch to bring everything back close enough to the hull (quarter-mounted propellor on a smack hull) and incidentally giving me the clearance for a shaft anode, plus bring the A bracket mounting blocks better over a frame.
That means I have to tap threads further up it (the shaft tube): Whitworth 55 degree, 14 G on a 1.5 inch outside diam. bronze pipe. Totally unavailable here. Nice engineer said he could turn the thread on the pipe for me on his lathe, but it's glassed into the boat. Don't think Edith would enjoy the spinning experience.
SO: if I describe the A-bracket, perhaps someone can tell me who made/makes it. They may be able to help me with tapping equipment.
OR: does anyone have a 1.5 inch whit. 14G steel nut (also of course totally unavailable here) lying about I can beg or buy for undying gratitude, etc.. Then I can do the old trick of the clever diagonal cut in the nut which makes it into a thread cutter.
BORING DESCRIPTION OF A-BRACKET:
It's bronze, of a type formerly often seen. Probably installed new on Edith in around 1985. No maker's name, just the number 205 on the mounting plates. Cast mounting plates roughly 3.5 inches square, four countersunk screw holes for fastening to hull, with a bit sticking out to accept the arm of the A (or V) - this sticking-out bit is wider than the arm, with raised edges like a shallow channel, to positively locate the arm. Holes in channel bit tapped to take bolts through arm. The bronze arms (1 and 1/8th wide by 3/8ths thick) are not drilled when you buy it new, so you can cut it to size (ha,ha!) yourself then drill it . The lump at the lower end of the "V" containing the cutless bearing is in three parts - the middle one of which is integral with the arms; the rounded/slightly pointed section at the propellor end has two large flats so you (or Charles Atlas) can unscrew it with a very big spanner; the forward end has the water lubrication holes in it, and is tapped to screw on to the tube.
Anyone recognize it? Or did half-a-dozen factories all make virtually the same thing?
We in fact have a spare, brand-new and exactly the same, which we saw by chance in a second-hand chandlery and snapped up in case we ever came down hard on a hard place. I would prefer to go on having a spare though, in case we ever come down...... So I'd rather not use it to correct the stupid mistake, when all I need is re-threading (apart from a new brain, that is.).
I now have a great deal of respect for those clever people on this forum who manage to ask for help in no more than two sentences!
By the way, can one get superscript little high and low letters/numbers on internet posting pages in order to efficiently write fractions? What knob do I press?
Help!
Richard
<hr width=100% size=1>LowTech
