October 2nd, 2007 - 8:48 pm

The Gray Ghost

We had a family gathering in Folly Beach, SC this past weekend so I looked up the local r/c sailing club and found out that they have club race events every Wednesday and Sunday. I sent an email to the webmaster at their website and was quickly invited to join in with the understanding that most of the club sails Soling One Meters. I packed up Bonnie, G’ma, the dog, and the boat and headed to the coast on Friday evening. After surfing with my brother, playing horseshoes, a low country boil, and a whole lot of relaxing on Saturday, I found the park and the beautiful pond easily on Sunday morning. We drove up a little late and there were already several boats on the water. Bonnie helped me carry some of the gear from the parking area across the street to pond side and I was immediately and enthusiastically greeted by the club’s Commodore, “Crazy Erv”. While setting up my boat, I inquired about radio channel and told Erv I was on 68. I was informed that there was already a club member on 68 and I felt myself on the verge of disappointment when Erv quickly said “no problem” and returned with a crystal set that I could use for the afternoon on 65. Elated, I quickly swapped out the crystals in the receiver and radio and finalized assembly of the boat.

At the beach house, the wind had been howling all weekend with gusts in excess of 22knots. At the pond, the breeze was a bit more gentle but there were some lulls, some crazy shifts, and some monster puffs still finding their way down the pond. The rest of my family eventually joined us and hung out at the park watching the racing as Erv creatively announced the races providing entertainment for all. Immediately Erv began referring to my boat as “Gray Ghost” and I think I like it. (NOTE: he later said that he always thought primer was fast for it’s hydroscopic properties….if ONE MORE person asks me “what color are you going to paint the boat”…..:-) )

I started my first ever r/c race with approximately 10 Soling One Meters and I was cautious to stay out of their way as I was the odd ball and didn’t want to mess with any club series or anything they had going on. I started in a big pack on the start line and struggled to get clear around the course. As I was near several other boats I steered wide letting them duke it out for their racing and I think I finished in 3rd. Several races later, I felt more comfortable mixing it up with these guys and when I started elbowing for starting room and getting clear, I would quickly jump out to a several boat length lead by the first mark as the US1M is a bit more powered up than the Solings. I won several races and didn’t win some more because of poor tactics or boat handling on my part. I did learn several new things about the boat and seeing it compete with other boats was very helpful (even though it wasn’t a fair fight). I’m ecstatic about the speed the boat displayed and several club members who were familiar with US1M boats expressed opinions that the boat has great potential and really had great speed when I wasn’t “dumb thumbing” it (my wording).

I also had my first ever collision with the boat as I tried to roll under a couple of starboard boats toward the finish line. I was also on starboard and close-hauled as one of the boats in this group peeled away reaching under the two other boats I was trying to pass (I believe he was trying to get somewhere he could do a penalty turn or get back to the mark he missed). I couldn’t see him through the other boats until it was too late and I t-boned him at full speed. Neither of us received any damage (although I am amazed he came out of it unscathed) but I was surprised at his reaction that seemed to imply that I was on port and at fault. I let it go since I really don’t know these personalities and I didn’t want to start a fuss.

As far as the boat performance goes, the mast and rig are not quite right yet. Under heavy close hauled pressure, the mast inverts and bends rearward in the middle even though I had a ton of backstay on. This is undoubtedly a result of having straight spreaders and I think installing a set of raked spreaders will prevent this reverse bending. The second issue I had was with the sheeting post in the middle of the boat being too high. The boom is not clearing it when the vang is really tight so I couldn’t crank on the vang and get the mainsail to gybe properly. Additionally, I was losing a lot of leech tension between setting it up on the beach and sailing - but I believe that is a result of not being able to maintain the mast prebend while under sailing loads. The last issue I had was with the Futaba servo. After about 1.5 hours of sailing, I lost the ability to sheet in under load. I would have to tack immediately after rounding C to give the servo a chance to reel in the sails. Once there, it would hold them fine. I had full rudder control so I doubted I was having a battery problem but I changed out the battery pack anyway to find that it didn’t solve the issue. I kept racing but will need to remove and test the servo later this week. I suspect something has gone awry inside the servo guts….I was impatient when I mounted that servo and radio board - removal of the servo is going to be difficult.

I want to take a moment to give a “shout-out” to the Charleston Model Yacht Club for being so inviting and accommodating to me and my one meter. I had a blast and can’t wait to go racing again! Next time, I hope to get some one design racing in for a fair challenge.

August 5th, 2007 - 11:15 pm

Joggle This

For the first two hulls out of the mold, joining the two halves has been tricky because I hadn’t quite worked out how best to make that work. I was satisfied with a little extra time to join the two halves and fair them - but that won’t do from a future production standpoint. After some research, I set out to create a “joggle”. I doubt this is an official term but it’s one that I picked up from some detailed online documentation about a full scale glider build project…I’ll blog about that site later this week.

The joggle is a separate piece that will bolt into the starboard hull mold and will create a small offset on the lip of one half of the hull so that it will fit inside the opposing side.  This will (hopefully) leave a perfect surface for a glue joint and the capability to join the halves inside the molds with a high degree of repeatability and consistency. The joggle mold piece must be removable because it is opposite to the draft of the mold and creates a mechanical lock in the part being molded.

I created the joggle by waxing the mold and the original plug and then building up a fiberglass strip along the edge. Before I removed the newly created part, I drilled 16 holes through both the joggle and the mold, applied nuts to the back of screws inserted through the holes, and, after applying release agent to the exposed threads, and globbing resin and microballoons on the back to seal them so they won’t leak vacuum when vacuum bagging the next hull. This way the piece can be very accurately located each time it is removed and installed.

Then, with the joggle removed, I was able to clean up the flat edge, mask off the mating surface, and begin laminating glass to the side that will touch the hull.  This lamination will be slightly thicker than the hull thickness so it will create the appropriate offset of the fiberglass part.

Next, once everything is cured, I’ll sand the newly laminated fiberglass flush with the mating surface, trim up the raised edge for a consistent lip width, and apply some finish to the joggle so there are no sharp points that might puncture the vacuum bag.

Earlier this morning, Neville came over to get some key measurements and some small pieces parts to continue his build of hull #2.  We got most of his rigging points made, mounted, and glued into the hull.

July 30th, 2007 - 8:36 am

Variation on a Theme

Hull #2 of The Bogy is nearing completion as fellow designer, Neville Cork, is finishing up the body work on his ideas of the deck layout. The rear sugar scoop extends much further forward than mine and his hatch opening is longer but narrower too - I’m looking forward to seeing his final thoughts with regards to control lines and he’s apparently got some trick for sealing the hatch that I can’t quite make out in this photo.

Neville had previously designed a skiff-style US1M that he brought out and we did some sailing against on Saturday.  These two boats were very different in design philosophy so it wasn’t a refined “test” but the Bogy clearly had a performance advantage.  I look forward to getting it up against some other US1M boats.  In an unusual departure from standard, I didn’t take my camera along and only had a camera phone.  Here’s the only sailing photo for the day, which inconsequently, also shows a dragon fly on my head.

July 17th, 2007 - 8:50 pm

Video of the Launch

There wasn’t much to speak of with regards to the wind, but it was a good afternoon to shake out the boat. We’ll get some higher wind footage and some on-board video soon.

Launch

Click HERE to view / download the larger version of this video (15Mb).

July 17th, 2007 - 7:53 am

The boat is launched!

I launched the boat yesterday and sailed it twice. It was an outstanding success! She handles very well with only a bit of weather helm (this is desirable from a performance standpoint as far as the underwater foils are concerned). I’m fortunate to have this pond on the property where I work so I can take it out at lunch or after hours. During lunch, the wind was a bit fluky but had an occasional sustained 8 knot puffs come down the lake. She remained dry as a bone inside and the rig / sails look exceptional with a bit of pressure on them.

Later, on my way home at about 7pm, I drove by the upper pond and the wind was a nice steady 8 to 10…a quick call to Bonnie to relay that I wasn’t coming home just yet, and I was sailing again 10 minutes later. 10knots is getting to the upper range of this rig and I took a couple of knock-downs going upwind where the boat laid over and I lost helm until I eased the sheets. After a long upwind beat and another tack, suddenly the boat felt terribly unresponsive and I began to wonder if I was having radio trouble. I finally managed to get the boat to bear away and control did come back. I decided I would make an inspection so I pointed the boat onto a reach back at me. I immediately noticed that the mast was bending off to leeward and upon inspection, found that during tacking, if the sails flog a bit, they can shake the shrouds out of the spreaders (spreaders are slotted … it’s a long story). A little tape or thread holding the shrouds to the spreaders will solve that.  I also realized that I forgot to cover up the drain hole in the upper right corner of the stern.  However, even that didn’t allow in a single drop of water even through the knock downs and excessive healing.

We took some video this afternoon and I’m doing a little editing on it - will probably have it up by the end of the week.

July 11th, 2007 - 4:01 pm

The rigging

The mast and sail rigging is complete now and the only lines left to run are those to the main winch servo.  I hope to work on re-installation of the deck hardware this evening.  The main sail and jib sail clew attachments to their respective booms is done by means of a rubber grommet that tightly fits the .25″ carbon fiber boom.  They fit tightly enough to not move under line pressure but you can slide them up and down the boom manually to adjust the angle of the clew attachment for better sail shape control.  The jib tack is tied in place to the leading edge of the boom, but the head has a tension adjustment on it.  As for the main, I have temporarily tied the main downhuaul in place but will work out some sort of adjustment on this in the future.

The vang worked out particularly well and the carbon fiber bowsie presents a great deal of “bling”.  All long line terminations at this point are neatly spliced - no knots unless they are on extremely short lines (like the ones holding the main sail to the mast or the ones wrapping the grommets).

July 9th, 2007 - 1:47 pm

Lead Mold

Lead is heavy but it flows almost like water when it’s molten!  I found this out when the old mold half (on it’s second cycle) cracked mid-pour on Saturday.  As you can see evident in my pouring stand / setup, I was concerned about this possibility and wanted to take precaution that molten lead did not end up on me.  I put in a blast shield constructed of 3/16″ plywood and an old towel in the workbench to shield me from the pour…good thing too.  As it turns out, when the mold cracked (ever so slightly), the lead went between the mold and the plywood and just pooled and cooled there.  I gave it just enough time to cool and seal the crack before I finished the pour.  The crack should not have been result of moisture in the mold because both halves spent 1.5 hours in the oven at 350 degrees.  However, this mold half was showing some hair-line cracks and that’s why I built the other half mixing in strands of fiberglass into the Rock Hard Putty.  Although it needed a little extra finishing work, I still ended up with a usable bulb.  If you recall, I also made a slot in which I could embed a piece of the same aluminum extrusion that forms the keel strut.  I was quite concerned that I wouldn’t be able to remove the aluminum piece after the pour, but it came out with surprising ease.  No tools required.

 

I still feel obligated to remind you that lead is a dangerous substance to work with.  It is toxic to the body and presents a very serious burn hazard in molten form.  If you work with this stuff, be sure to protect yourself from the shavings and dust, wash hands, and be overly cautions when it’s hot.
July 9th, 2007 - 8:56 am

It Floats (and doesn’t leak)!

More later, good progress made this weekend on rigging and keel fin.  Maiden voyage might just happen this weekend!  And yes, for the last time, sans a few accent stripes, that is the final color (why does everyone keep asking me that?)

July 5th, 2007 - 8:34 am

I Can Taste It

After seeing an “early show” of fireworks on the 3rd with Bonnie, the 4th provided a solid day of work on the one meter.  I set out first thing to make the little pulley block I had dreamed up the other day.  While I did save $10 by making this thing myself, after the first three tries, I had almost 1.5 hours invested in it…the next ones will be faster!  I used some .030 aluminum plate and cut out a simple flat shape, drilled one hole, bent it, drilled the sister hole, cut a piece of 1/8″ aluminum tubing to fit the center of the sheave, and assembled with a 2mm screw and nut.  It sounds simple but it took several attempts to get the bend right in the middle and I finally discovered that it bends perfectly around the end of a pair of forceps.  A small hole in the middle of the bend provided room for another 2mm screw to fasten it to the deck.  I suspect, however, that I will need the aluminum plate to extend beyond the top and further back to keep the line for shaking off the sheave and jamming.

Because the aluminum mold is a bit delayed, I also worked on getting the putty mold repaired to cast another bulb or two.  If you remember, this mold was poured in two parts using a PVC plug in the middle suspended in a box with a screw.  The first half that was poured saw the air bubbles suspend at the surface right against the plug.  There was really no way for us to eliminate them.  The second half did just fine since the plug was at the bottom of the pour.  The air bubbles caused a problem when I poured the lead and the rapid expansion of the air in those pockets caused the mold to chip out.  I used the old top half, without the air next to the mold surface, as a new bottom, and poured a new top - I put fiberglass in this one to help with some of the minor cracking that seemed to happen too but now I wonder if that didn’t trap some air bubbles near the mold surface again.  We’ll see when I pour again.  This time around, I attached a small section of the keel spar so I can maybe leave a piece in the mold to create the slot I need to attach the real strut when pouring the lead.  With any luck, I’ll be able to extract the aluminum piece from the poured lead leaving a nicely fitted opening.  I have some doubts that the aluminum will come cleanly out of the lead though.  This way I could get more precision with the slot.

While that setup, I finally installed the rudder servo in the underside of the deck.  I realize that most things need to sit down low, but this is a very small light-weight high-torque micro servo and it really reduced the amount of linkage needed to get it to drive the rudder.
  Because the screws would be really difficult to get at for the servo arms, I made a fiberglass / balsa box that glued to the underside of the deck that had grooves for the servo mount flanges and a cover that screws on it to box in the servo.  It works great and has no play.  I also decided that I really didn’t like the ratchet action of the sail control stick on the new radio (usually intended for throttle on an r/c airplane) and wanted a smoother action.  I discovered that if I take the ratchet detent spring and flip it over, that it gives a much smoother action and still provides enough resistance so the stick will stay where you leave it.

Next up was some filler on the hull half joints and a few minor imperfections.  Before I did that though, I marked the location of all the holes and hardware and took photos to have documentation so I can find them later if they get covered up in the finishing process.  Finally, a coat of primer.

July 2nd, 2007 - 10:36 pm

I see a light

Yes, I realized tonight that I can see a light waaaayyy down the tunnel.  If we’re lucky, it’s not the headlight of a train!

I guess when you work on a long term project over so much time, you rarely (well, I do anyway), pick your head up and look ahead.  Tonight, I looked at the boat and thought that I could be within a couple of weeks of a test sail.  I have ordered what should nearly be the last of the knic-knacs for the boat, a 2mm tap, some 2mm screws, nuts, washers, a 4-40 tap, etc so I can make some of the hardware I need.  By the time I purchase two miniature turning blocks at $8 each, I can easily make them and buy the tools required for less.

Tonight I present the pictures of the installed radio tray…its a bit dusty and needs some cleaning but here it is…also shown with the hatch lip I installed over the weekend (not terribly pretty yet).

I didn’t spend much time with it this evening, but I did work out the geometry of the sheets, main and jib sheeting points, and the other related hardware and control lines.  Tomorrow I’ll take the sail rig into the shop and finish the rig by shortening the booms, tying up the outhaul grommets, and adding the sheeting points.  As for the boat, if my tools come in tomorrow, I’ll get the deck hardware mounted and it’s going to be time for some primer.

The aluminum machined mold for the keel bulb is not going to be done terribly soon so I’m going to rebuild the plaster mold we made late last year using the same PVC plug.  The lead, once cast, will require a little more finish work but it won’t be too bad.

I should make a list (edit: geesh, I keep adding to this):

  • Install sheeting hardware (must cut temporary access hatch in bow since the Team Seacats dummy sealed up the main bulkhead before the wood reinforcement was in place up front). need taps for final hardware install
  • Make a slew of bowsies
  • Install sheeting points on the booms, replace temporary Dacron lines with spectra including outhaul grommets - do some eye-splicing if there is time
  • Build the main boom vang
  • Install rudder servo, rudder linkage, and linkage boot
  • Mold new lead bulb, machine for strut, cut and drill strut, make keel fin (this could take some time)
  • Primer, Paint, wetsand, clearcoat, wetsand, buff
  • Sail

Oh and if you noticed the picture quality improved, it’s because the replacement camera charger arrived…and not 3 hours after I found the old one (in the closet with the spare light bulbs of all places - told you I left it somewhere stupid).

June 30th, 2007 - 8:50 pm

Radio Tray Installation

The radio tray is installed.  The large taper on the tray both accomodates the widening of the hull and puts the tray at a bit of an angle so that the line enters the winch in a straight line.  Pictures of the installation coming tomorrow.  The entire tray weighs slightly more than 0.5oz!!!

June 30th, 2007 - 8:55 am

Radio Tray

Today we finish the radio tray installation…here’s the plan…I left some extra room for the battery because until I get a special LiPo charger, I’m going to use the 600mA Nicad that came with the radio.  I know that’s not much capacity for a day of sailing, but I do have three or four of these packs lying around.

June 25th, 2007 - 9:37 am

Rudder Mold

I made my first, and last, rudder out of the new rudder mold.  The result was pretty good.  Although I brushed in an early thin layer of epoxy in the mold with the intent of holding a nice outside finish, I didn’t let it cure enough before vacuum bagging the carbon and the vacuum sucked the still-to-soft resin out leaving some pinholes between the carbon weave.  After trimming away the rest of the pieces, I put in some filler but will probably have to make another pass to get it right.  I filled the core with a thick epoxy / microballoons (tinted dark gray) before sandwiching the two cured skins back together in the mold.  The rudder looks good and while it is probably about average in weight, I think I can cut a little more weight out of it.  The brass rod itself weighs as much as the rudder so first step would be to find a lighter alternative.

Oh, the reason for the “last rudder out of this mold”?  The newest mold-half warped badly while cooling after I left it in the sun curing the rudder.  I’m getting tired of looking at this rudder mold and don’t think I’ll remake this half again until I need another rudder.  I think maybe I laminated the mold too thickly in one step…or something.  Might have to talk to some folks to figure out how to keep this from happening again.

I also worked out the bulkhead and radio tray material.  I took some light weight PVC foam and ripped out a .25″ thick sheet from a large block.  I then planned the position of the main servo winch and using a razor blade, cut out the foam to receive two balsa blocks to provide something to screw into for the winch servo mounting.  I then vacuum bagged one layer of 5.7oz carbon cloth using epoxy resin to each side of the foam.  It’s amazing stuff.  The whole sheet ways a touch over 2oz and is enough to make the main bulkhead and the radio tray.  I admit to being a little stumped for a while trying to figure out how to template the bulkhead without a ton of trail and error fitting.  I finally decided to utilize the hull molds to make a template so I marked the position on the molds with electrical tape and laid up two layers of 1″ fiberglass tape in the same area where the bulkhead will be inserted into the hull and used those to trace a template on the foam core carbon material.  After trimming the carbon, I fitted the bulkhead and with only some minor cleanup of the resin where I had placed fixtures inside the hull it fit perfectly.  The bulkhead is flat on the bottom leaving an opening for water to drain out of the front of the boat should there ever be a reason to do so.  It will be much easier to perform the assembly of the shroud connection points and mast compression post in one step next time.
 

 

  

I’ve also been trying to sort out how I can mount the keel trunk and get it accurately placed.  Obviously a jig of some sort would be great but I need to have the first one setup to jig anything.  I decided to hang the boat from the stern and the bow and use a level to sort out squaring up the keel.  For the fore and aft measurement, I measured the height of the waterline at the bow and the stern from the floor getting them pretty level (I know where the water line is from the computer design and verification through the float test we did several months ago).  With the keel trunk attached inside the hull to a long aluminum bar (that will later be in the center of the future keel foil), the bar acts like a pendulum and as long as the hull is level fore/aft and side/side, the bar will be plumb where I want it.   I’ll glue up the main bulkhead and the trunk together at the same time and fit the radio tray in as a sub-deck reinforcement to the keel trunk later this week.  It should be very solid.

June 23rd, 2007 - 11:39 pm

Success!

Aaaaaa…more on that later….I’m not sure which needs a rest more - the washing machine, or my favorite t-shirt…

June 21st, 2007 - 10:01 am

Do Over

Gosh I hate titling a post that way.  The second half of the rudder mold did not come out well.  It appears that I applied the gelcoat far to thick and it got too hot causing the PVA to outgas and causing the gelcoat to lift at the trailing edge of the rudder.  It is not salvageable.  The first half of the mold is gorgeous…I’ll have to start over on the second half….spraying that gelcoat isn’t looking so bad now.