Jump to content

Pete McCrary

  • Content Count

  • Joined

  • Last visited

  • Days Won


Pete McCrary last won the day on March 24

Pete McCrary had the most liked content!

Community Reputation

53 Excellent

About Pete McCrary

  • Rank
    Advanced Member
  • Birthday 01/30/1934

Profile Information

  • Gender
  • Location
    Manassas, Virginia
  • Interests
    Small boatbuilding, sailing, cruising, woodworking, history ..

Recent Profile Visitors

4,471 profile views
  1. A few days ago I was able to recruit an onlooker at the ramp to take a video of Chessie's launch. This time I backed the trailer into the river with the water just about an inch below the the WL boot. That put the wheel bearings just under water. Here's what it looks like: This shows position of the rig just prior to the launch video. Next is the video of the actual launch. I just let the pickup and trailer coast backward about a foot, then hit the brakes! That overcame the "slip/stick" effect -- and she slipped smoothly into the river. IMG_1928.mp4 In the pickup I carry a can of Johnson's paste floor wax -- and before recovery give the trough a good swipe. This time the trailer wasn't so deep into the river [than the first time] which caused a little harder cranking on the winch. The last foot or so I shifted to the low gear. The winch hook was attached from the dock and the boat nudged onto the end of the trough. Once in the right place the tug of the winch cable kept her "lined-up." Shown here after recovery. I consider the modification a significant improvement for both launch and recovery -- AND a much gentler highway ride for the boat. Probably less trailer maintenance as well. Next time I'll see how it worke if I back only so far as to keep the wheel bearing dry.
  2. Nice work Amos. You'll find the shelving very useful. For builders who haven't installed the sheer strakes -- it's much easier to install the shelf-supporting cleats before doing the s-strakes. Same for any drawers you may want that may be stowed between Blks 4 & 5 that [for easy access] slide out over the bunks. For Chessie I'm still trying to figure out where to put hangers for shirts, hats, jackets, etc.
  3. "Skeena" really looks nice. Hope to see her in October. I like the name and history of the nice kitten. We have two cats -- half sisters from a farm. Same mother, different Toms years apart. The oldest (14 yrs & all black) is very "skitish," and a third the size of the younger (6 yrs & orange). Our 4 kids and 11 grandchildren have never seen the older one. -- but she's very affectionate with me. But the young orange one pals up even to strangers.
  4. Thanks for the suggestion Mike -- but I couldn't make it work. However Frank Hagan got into the "codes" and all is well.
  5. Yesterday, April 1, was the launch test -- abbreviated. The trough worked just fine for launch and recovery. Much better than the three rollers that I was using. Here's how it went. Hampered by a very low tide and shallow ramp caused by three days of strong winds pushing water out the Potomac. I wanted to be into the water as little as possible -- but I was worried that the sliding boat might "plow" into the concrete ramp (just about 15" where the boat would plunge into the water off of the trough). The above photos show where I wanted (but didn't) launch. The tires were in the water, but the wheel hubs just above. So, I backed down a little deeper. Later in the season, I'll try a shallower launch. Wheels under, but not the fenders. Boat not yet floating. Next I unhooked the safety chain and the bow eye, drifted back a few inches and "tapped" the brakes. Chessie just smoothly slid into the water -- pretty-as-you-please. Shown above she floating but secured by her bow eye ready for recovery. Notice the yellow stripe on the dock -- that marks the end of the concrete ramp. You can see that the trailer wheels are not far from it. Recovery was easy, single-handed. Nudging boat's keel onto the trough (above photo) -- I took the winch cable and hook onto the walking-boards and secured it to the bow eye -- then (using the "high-gear" on the two-speed winch crank) she was easily pulled full-up onto the trailer. The effort was much easier than that required to recover over the rollers, where near the end I'd have to switch to the low gear. I think the damaged rollers weren't "rolling." She's part-way up. I think this is the full-up position at recovery. At launch the mooring lines would have been cleated to the dock. She's full-up and secure. Next time I'll try launching (and maybe recovery) with the trailer backed down the ramp just so the wheel hubs are dry. So far I feel pretty sure the wooden trough approach is much superior than the rollers. And simpler! KISS.
  6. The original trailer for Chessie (a Core Sound 20 Mk 3) carried her (1" yellow pine keel w/SS half-oval) on three hard-rubber rollers. The side bunks were adjusted to carry loads just enough to keep her balanced at the verticle. That arrangement concentrated her load on just three places and, over many miles at highway speeds, the stresses caused by potholes, RR Xings, unseen speed "humps," etc., -- caused the rollers to be severely damaged at their centers (the only load-bearing part). Note that there has been no noticeable damage to the keel. The chipped-away rubber pieces made the roller no longer cylindrical to the point that they often didn't "roll" at all -- causing launching and retrieval problems. I learned that Graham had similar problems and was considering a trough with many rollers. That reminded me that I had used flat platforms to carry my CLC PocketShip and a Com-Pac Eclipse (both had, respectively, wide ~2" & ~4" flat keels). So, maybe the concept would work for a CS20.3 and other boats without flat keels. So, here's what I came up with. This shows the rip-cuts made on a 16' X 2 X 8 straight piece from Home Depot. The bottom of the board was covered with two epoxy saturated and overlapping (only by an inch at the center) 4 inch X 10 ounce FG tapes over the entire length. The top and sides were covered with three coats of neat epoxy -- and the top with a final coat of neat epoxy mixed with powered graphite. For Chessie's trailer I trimmed the 16' trough down to just 14 feet. The "rough cut" cross section. The sharp edge of the half-round centerline trough was rounded over with a smooth plane. The 4 coats of neat epoxy tended to collect (at bit) at the bottom of the half round -- which was desired, as it would carry the concentration of stress and sliding fiction. BTW, the half round SS screws (thru the keel's SS half oval) were "smoothed" over. I measured the height of each roller (above) their wooden mounts and planned to mount the trough such that it's bottom would duplicate the position of the [three] rollers being replaced. Alan provided me with offsets (from the waterline) of the keel at the three points where the rollers were mounted on the trailer. From this I determined that the mid support (under the trough) should be ~ 1 and 15/32" lower than a straight line from the forward mount to the aft mount. Trough lined up on the trailer centerline. Forward support with spacers. Notice X-beam doubler (new wood) under. View from port side slightly aft. Middle support. Trough is not loaded. Now the trough is artificially loaded with clamps. When the boat was lowered onto the trough, there was ~1/2" space -- into which was placed a spacer. Aft support. Shallow-V guides to help guide the keel into the trough. Note that the CB catcher is raised so that the CB won't hang up on the X-beam. The centerline of the trough was further lubricated with paste floor wax. Next I'll report the proof-of-concept trial launch and recovery.
  7. Well Chessie's dinghy, "Catnip" (a Two Paw 7), is finished (except for painting her interior a "battleship" gray). So I'm finishing the conversion of Chessie's trailer from 3-rollers to one 16' trough. Today applied the last coat of epoxy with one tablespoon of powered graphite. Here's a photo: Once the cure was at the "thin-film set" stage -- can you believe that I was allowed to move the sixteen foot epoxied 2x4 board into our living room to cure in 70 degree comfort? Now that's a wife you can live with for 60 years (come July)! I'll smooth out that groove with 400 grit aluminum oxid paper. Once installed, I'll help it be nice and slippery with some paste wood-floor wax. The loading will be reduced from ~500 lbs/roller to just ~100 lbs/foot, or only about 8 lbs/inch! I think the keel will be much relieved and the boat will have an easier highway transport. Chessie is in a lift at Backyard Boats in Woodbridge so that I can have the trailer at home for the modifications. Too much sunshine! Better pix later. Forward roller (aft to right). Middle roller. Note "walking board" going forward (to left). Very useful (recovering) for attaching winch hook to bow-eye and keeping dry. Aft roller. The board at the bottom of pix is the CB catcher. This keeps the CB from ever dragging on the highway -- and also never hanging up on the aft cross member when launching. Once the new trough proves itself in a trial launch -- I'll discard the rollers.
  8. My DN iceboat (sail #2141) could definitely make way downwind faster than the wind -- but not directly downwind. To do that we had to tac (jibe?) -- during which we had the [apparent wind in our faces]. Here's a link to a wind-powered machine that goes much faster directly downwind than the wind: https://www.google.com/search?q=going+downwind+faster+than+the+wind&oq=going+downwind+fas&aqs=chrome.1.69i57j33l3.38470j0j4&client=ms-android-verizon&sourceid=chrome-mobile&ie=UTF-8#imgrc=_ An iceboat sail performs just like a propeller blade with a very large radius. The skipper of an ice boat is always pulling hard on the sheet (usually with x6 purchase) on any heading mainly to flatten the sail which improves its L/D ratio.
  9. The "polar plot" shown previously is not for a "water" boat, but for an idealized iceboat (steel on ice friction & windage, both) = zero). The plot is with respect to a wind-speed of unity. A water Catamaran would have a polar plot looking something like this: And it would look different for various wind and wave conditions. Years ago I had an Auqua Cat with an A-frame rig holding up a lanteen loose-footed sail. On smooth water in a good wind it made better progress downwind by tacking as opposed to going directly downwind.
  10. Reacher: What you need is a polar plot of your boat's performance on all points. For a boat with zero friction at the "interface" (which an iceboat approaches because steel on ice friction is very very low) -- the polar plot approximates a circle. It looks like this: The vector W is the wind velocity and V is the boat velocity (showing speed and direction with respect to the wind vector -- which is straight up the page). The circles represent the boat's performance expressed as a function of its heading and the L/D (lift to drag) ratio of its sail (ignoring the boat's windage). So, an iceboat with a sail having an L/D of 3 (typical) or 5 (high performance) can, on a broad reach make V = 3 X W (typical) or V = 5 X W (high performance). Note that directly downwind the polar plot shows that V = W no matter what the L/D is. The horozontal L/D of a keel-less boat is quite poor, but is vastly improved by a centerboard, especially one with a hydrofoil with high aspect ratio (length to width). For steel on very smooth ice, the "L/D" is probably close to the inverse of its coefficient of friction. The velocity polar plot is affected by these performance figures (in each medium) for the vehicle traveling in this "ancient" interface -- water/air for boats, hard sand or Tarmac for land yachts, Gravity/air for airplanes, air/string/anchor or surfboard (gravity) for kites. Note that iceboats always sail "close hauled" even when on a broad reach -- and, because they are going much faster than the wind, the sail luffs and a gibe is quite tame. The polar plot shown above was in an article that I wrote back in 1974: I don't know the link, but the article is available on the Internet If you had a compass, a good GPS plotter, a steady wind, and a lake with no tide or current, you could easily create your own polar plot and determine the best point to sail in order to fetch any destination in minimum time.
  11. Green also goes nicely with buff tan -- remember the Jaguar sports car with a buff tan canvas top and British racing green body?
  12. Green bottom. Next the white topsides, then gray interior. Maybe I'll make the aft seat green too. A pair of oars ordered today. Getting there -- six more days of painting.
  13. And when I started my law practice in 1977 my secretary and I had to use an IBM typewriter and carbon paper because I couldn't afford a Xerox copier for the office. It was like the dark ages. On the other hand, I wonder how historians (a hundred years from now) will be able to root out true history? Where will they find and authenticate uncorrupted ones & zeros (recorded as invisible electrons, micro magnets, photons, etc). Won't the number of ones & zeros approach or exceed the total of all protons, electrons, neutrons, etc in the universe? I'm glad I won't be my problem.
  14. Here are the rest of the photos. I tilted her so I wouldn't have to fight gravity while gluing on the tank sides. Cleats ready for the tank sides. A place to stow stuff in the tank and still be useful for flotation. The aft seat will be held in place with a bungee cord. The styrofoam will go into the open space under the mid-ship seat. It's hard to get at anyway. The space under the removable seat is still available for stowage. Annie, ready to help with cutting Catnip in half. Note the hold-down bungee at aft end of the keel. Turned her over. Annie is so pleased -- she signals "no hands" now. This is the last cut. The nesting Blks were spaced with small pieces of 1/16" cardboard. I used a Japanese "pull saw" with a thin blade. But they are so sharp I had to be especially careful to keep it from "drifting" and cutting into the Blks. But the glue used to place the cardboard pieces was harder (than the Blk wood) and there was a little "drifting" of the blade. That was later corrected with fairing compound. IMG_1838.mp4 The video shows Annie and I "nesting" the two halfs. Press the "arrow" to view the 30 second video. I don't know why there is no "postage-stamp" image.
  15. The Two Paw 7 was started back in early 2018 and was interrupted by that year's sailing season. Her name "Catnip" was suggested by Steve Warfle as the intended tender to my CS20.3 -- named "Chessie" after the C & O RR's sleeping kitten -- which previously was named after our beloved Chesapeake Bay. Here are a few of the "build" photoes that were accidentally deleted. The nesting bulkheads. Cradle and build setup. Going 3-D -- the first step. 3-D complete. Getting ready for the bottom. The all-important gunwales. Port & Stbd glued at-the-same-time to preserve semmetry. The end pieces are temporary to provide purchase for the extended gunwales. The kit provided pressure treated 1/4" strips to be x3-laminated for each side. But they became (over time) severely warped -- so I found some cedar clear of enough knots to rip 6 eight foot pieces. Hopefully, the cedar will hold up over time. Ready for trimming. Flotation tanks and aft seat supports. More in the next posting.
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.