Collection Home
|
|
 |
| Front | Rear |
 |
 |
 |
| Left | Right | Open for Rigging |
I acquired this bobbin from Collectibles from Maine in 2024. I have no information on who made it or when it was made.
This bobbin is 218 mm. tall, 50 mm. wide, 56 mm. thick, and weighs 436 g.
The two side plates are made of 1-1/4 by 1/4 inch (32 by 6.4 mm.) aluminum alloy, probably 6061. The ends of the side plates are dog-leg bent to converge. 10.7 mm. attachment holes are drilled through the plates at each end. The plates are bolted together with 1/4-20 UNC hex head bolts washers, lock washers, and wing nuts. The bolts pass through the center of the bollards.
The bollards are 3/4 inch (20 mm.) lengths of 2 inch (50 mm.) aluminum alloy rod, also probably 6061. The bollards have U-shaped grooves with an internal diameter of 37 mm. The bollards are bolted to one plate with a 1/4-20UNC countersink head machine screw that passes through the bollard about 11 mm. from the bollard center to prevent rotation or loss during rigging.
There are no markings on this bobbin.
This bobbin is larger than most. My first impression is that the side plates could be thinner to save weight while still being adequately strong. As is, this bobbin is robust.
Although the ends are not symmetrical (one is longer), this bobbin .s reversible. This helps spread the wear between the two bollards.
How might I modify this bobbin? The main feature that I dislike about this bobbin is the need to remove one of the bolts and its associated nut and washers for rigging. It may appear that one could eliminate one of the hex bolts, but this would allow the corresponding bollard to rotate on its countersunk screw. If one taped one of the bollards, it could be fixed to the fixed frame only. This would allow swinging the bobbin open for rigging without removing one of the hex bolts. The down side is that the two bollards would no longer be interchangeable. A better solution would be to use two countersunk screws per bollard. This would require some accurate - but straightforward - machining.
For far more content, use a larger monitor and a full-width window.
Hundreds of cell phone users complained and asked me to for a simpler, mobile friendly site. In particular, they wanted me to limit each page to a small number of pictures and minimize my use of text. This new site provides what they asked for.