Making your own blocks
pended from short lengths of chain, and that the two vang blocks that at- tach to the deck, do so via a short length of cable, and a hook. When the blocks are all in place, step the boom, if you haven’t already done so. Cut four lengths of thread, about 3¹₂′
to 4′-0″ feet long. Thread one end through each hole in the deckhouse wall, over a drum, and down through the floor. Pull enough down to let you bring it up and around the outside of the barge hull, and temporarily tie each one off to one of the towing bitts. The first set of tackle I rigged was the main boom lift. Bring the line up the mast, through the topmost block, and from there down to the two blocks, on the top of the boom. This line will be tied off at the block at the masthead. Position the boom at approximately the height you want it to end up at, but don’t worry about getting it tight just yet. Next will be the main lift tackle. The line will lead up the mast, and pass through the cen- ter sheave of the triple block mounted
3. 4.
3. At the top of the mast, the two spiders can be seen with the vari- ous eyes for the stays and running rigging blocks. The uppermost block is for the boom lift tackle and has two sheaves. The one just below it has three sheaves, one each for the port and starboard vangs, and the center one is used for the main lift tackle. As these blocks move depending on the angle of the boom, they hang from short pieces of chain. 4. A close look at the boom rigging shows that the main lift tackle hangs below the end of the boom. It is
block will need at least one, from which it will be attached to the mast or boom. In addition, if a running line termi- nates at a block, you will need a second eye. Depending on where you obtain your blocks, you may be able to avoid this step if you were able to obtain blocks with eyes already in place. I had some hard finished cotton thread that I used for my rigging. Some- thing along the lines of “button thread” is what you want, lighter than the wire
RAILROAD MODEL CRAFTSMAN
hooked onto a piece of chain fastened to the deck, and the slack is taken up when the derrick is not in use. Any slack is also taken out of the vangs. The two vangs angle back to a point on the deck at each side of the barge. They are used to slew the boom to port or starboard as required. As the angle of the boom increases, the vangs need to be moved further aft. There are three attachment points on each side of the deck for this purpose. The two blocks on the top of the boom comprise part of the boom lift tackle.
stays, but not ordinary weight sewing thread. If you are using regular cotton, pull it through some beeswax several times to seal it against moisture. Noth- ing looks worse than a ship model where the rigging has a case of the fuzzies.’ Using the plan, fasten the blocks in place using the eyebolts you placed on the masthead and the end of the boom. Note that the main lift block at the end of the boom and the two blocks for the downhauls at the masthead are sus-
just below the masthead. From here, it passes through the outermost of the two holes you drilled through the boom earli- er. (You did drill those holes didn’t you?) Then it passes through the block with the lifting hook and eventually termi- nates at the block at the end of the un- derside of the boom. I had installed two eyebolts in the deck, just inboard of the two forward towing bits. I fastened a length of fine chain between these to pro- vide a place to put the lifting tackle
57
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