This soaked up a lot of my work time, (The boss is going to kill me BTW) so it better get some response.
Like most of the equipment on the boat the outriggers had seen better days. It took some research and an accidental find in a magazine article to determine that these were made by Rybovitch, and probably date to 1970. Unfortunately, none of the parts, particularly the cast spreaders are available any longer.
The first option is to buy complete new outriggers, which will only cost about $5K to $6K plus installation. Being... ahem.... frugal, I elected that we could select option 2 and make some of the parts to spruce these back up. Simple right?
The biggest monkey wrench is one critical feature of these 'riggers; they can be lowered for getting under bridges. Without this option we run afoul of the new CG regs for drawbridges or at best have to wait for openings. The way they accomplished this is to attach the back leg of the outrigger to a slider which latches onto a pin on the lower spreader. Thus, the back leg can be slid up the tube which allows the 'rigger pole to rake back and drops the tips several feet. Here's a picture of the original setup:
IMG]http://i54.tinypic.com/2nhd9w5.jpg[/IMG]
Sorry it's not clearer, it's the only one I had. But if you look you can see that two of the spreader arms are broken, there's other hidden damage as well. If the antenna wasn't laying on it you could see all of the latch and slider assembly.
Anyway, our first step was to rule out duplicating the original spreader. It had already failed once. We investigated and decided that we could buy new arms from Lee's and make a hub to put them on. It started out with "Oh, we'll just make a collar and screw the arms into it."
Now when I say "we" it's not an editorial we. My friend and fishing buddy Mike happens to work as an Applications Engineer for one of the biggest CAD software companies around. Big as in GM designs and builds their cars with this software. He's got about thirty years of machining, engineering and CAD experience and best of all, a vested interest in getting this to work because of the "fishing buddy" part. So he sets to work modeling the components in 3-D and discovers a problem. A simple hub will not accommodate the latch and arms and guy wire attachment points. About three incarnations later he comes up with the answer:
IMG]http://i56.tinypic.com/fu7vp3.jpg[/IMG]
So here's the highlights of how we went about going from a CAD drawing to a part without the benefit of a CNC milling machine.
*Disclaimer: Several copies of the parts were made and the methods changed a bit during production, so there may be some discontinuities in the parts you see in the photos since it wasn't always the same part being photographed in each step. So, sorry for any confusion.
Step 1: Turn and part off two pieces of 4 inch round Aluminum stock:
IMG]http://i56.tinypic.com/2yws5mx.jpg[/IMG]
Step 2: Bore to appropriate diameter to fit outrigger tube:
IMG]http://i51.tinypic.com/4u80tw.jpg[/IMG]
Step 3: Machine bottom step into the part. The upper step is much more complex because of the guy wire attachment points:
IMG]http://i53.tinypic.com/mn2bo1.jpg[/IMG]
Step 4: Using your Bridgeport vertical mill, machine four flats for the arm attachment points:
IMG]http://i53.tinypic.com/15ass6.jpg[/IMG]
Step 5: Actually, this was step -1, make an indexing fixture to orient the facets of the part for machining:
IMG]http://i56.tinypic.com/10qkxfo.jpg[/IMG]
Step 6: Using a slotting saw, make cuts for the arm attachment point extensions:
IMG]http://i51.tinypic.com/35jcgvm.jpg[/IMG]
Step 7: Using the indexing fixture, mill material from between arm extensions. Two sides have some material left in to form an integral pin for the latch mechanism. Only one is necessary, but it was deemed prudent to have a duplicate 180 deg away since it interfered with nothing and would leave us with a spare in case of breakage:
IMG]http://i53.tinypic.com/t7odbp.jpg[/IMG]
Step 8: Fixture the part in a V-block and using the slotting saw, remove remainder of material from pin-side of the cross:
IMG]http://i56.tinypic.com/29zquy8.jpg[/IMG]
Step 9: Using the indexing fixture, mount the part on a rotary table on your Bridgeport Mill and remove material leaving the flanges for the guy wire attachment points:
IMG]http://i55.tinypic.com/2ajdy80.jpg[/IMG]
Step 10: Again using a V-block drill and tap for arm attachments and other holes as per the drawing:
IMG]http://i51.tinypic.com/24b673n.jpg[/IMG]
Step 11: Test fit arms and compare to original for size and function:
IMG]http://i54.tinypic.com/2hxn8s8.jpg[/IMG]
Step 12: After cleaning and deburring parts send out for tumbling and check assembly prior to sending out for anodizing.
IMG]http://i56.tinypic.com/xd9udk.jpg[/IMG]
Verify that part matches drawing:
IMG]http://i56.tinypic.com/fu7vp3.jpg[/IMG]
Obviously it's not as easy as all that. There's more man-hours in this than a new set of outriggers is worth, and these are only the lower arms. The uppers are simpler, but still required a lot of work. However, having the tools and the skills available, little cash outlay was required. So Project Avenger gets one step closer to tuna fishing without bankrupting her owner.
Hope you enjoyed our program today. Please share your comments and questions.