Starcraft Holiday Reno and Hull Repair

[Grandad]

OK, I've lurked here long enough. It's time to tell my story over a few instalments to this thread. Much has been completed, but much more is to come. I have a 1972 21' Starcraft Holiday aluminum boat powered by a 120 HP Mercruiser I/O. I purchased it about 10 years ago, but it's been in the family since new. It was kinda tired when I got it, but had been properly maintained. The only shabby part was the sun damaged vinyl on the top decks and the yellowed plexiglass side and centre windshield panels. Sorry, no before pictures. My first task, replacing the plexi was easy and made a world of difference to the boat's appearance.

On the first trip out, it was evident that the sleeper style seats were too low. They had been replaced several years before and were in excellent condition, but no-one could see the horizon in front without straining up from a seated position. Using the original seat box as a pattern, I made new plywood boxes several inches higher and covered them with Formica wood grain laminate. With the tops of the seat backs now just at gunwale height, not only could we see a lot better, but the seats were more comfortable for our legs. There's more under seat storage space now too.

 

[Grandad]

Re: Starcraft Holiday Reno and Hull Repair

Next, I replaced the stern deck aluminum sheet, replacing cowl vents, gas filler and mooring cleats with stainless steel fittings and relocating everything to better locations. I used Tremclad (Rustoleum) spray bombs in "Recreation White" that identically matches the original Starcraft "Bermuda Cream". When I lifted the old deck, I found water had penetrated the top of the transom and rot had set in. Not wanting to pull the engine to replace the transom, I tried a stop-gap fix. I replaced only the top 12" of plywood, tying the new ply to solid old ply with 1/4"x2"x4" aluminum C channel. I know, "Mickey Mouse", but I got several years use out of it.

Eventually, I did have to replace the transom when I discovered it was spongy below the engine. So the deck came off again and the engine split from the outdrive. I used a double layer of marine grade plywood, glued and stainless steel screwed dead flat together. For waterproofing, I covered all sides and edges of the transom with Formica laminate and sealed the aluminum deck sheet at all points. I used 1/2" thick white plastic sign board material to replace the original plywood collar/spacer on the inside of the transom. Since I already had the aluminum C channel, I re-installed it on the new transom. It's one strong transom now. I learned that the engine and outdrive disassembly and reassembly is not that difficult with the help of the OEM manual.

Having removed the original painted steel gas tank from the port side of the engine to allow better access to the engine, I discovered that the tank bottom was corroded and questionable for future safety, so I ordered a new plastic tank. The floor beneath the old tank was soft enough that I was able to tear it out from under the sidewall without removing rivets and screws in that area. The mice have been enjoying the warm hospitality of underfloor styrofoam.

 

[Grandad]

Re: Starcraft Holiday Reno and Hull Repair

Next was the wormy deck vinyl. After pondering options, I chose a wood look composite material from HD. The material is designed for use in outdoor patio decks. Deck board planks of the material were too thick and too heavy (and too expensive), but I found the same material in a U-shape trim piece designed to cap the ends of the planks. These U-shapes were about 1-3/4" wide and 6' long, but the material thickness was only about 1/4". I bought a piece and stain tested it with oil and also scratched at the surface across the grain. No stains. I found that any surface scratches can be removed by wire brushing with the grain.

Cutting off the "legs" of the U with my table saw left a flat strip 1/4" thick x 1-3/4" wide by 6' long. Gluing multiple strips to the deck with PL Premium created a teak look that years later looks as good as new. There's no evidence of the glue releasing and no creep from expansion & contraction despite the extreme temperature changes in our area.

 

[GA_Boater]

Re: Starcraft Holiday Reno and Hull Repair

Nice work, Grandad. Your "patio deck" looks great and original. Good re-purpose for the composite.

 

[Bondo]

Re: Starcraft Holiday Reno and Hull Repair

Nice work, Grandad. Your "patio deck" looks great and original. Good re-purpose for the composite.

Ayuh,.... Sweet lookin' ole Holiday,...

 

[ezmobee]

Re: Starcraft Holiday Reno and Hull Repair

Looks great. I really wouldn't have though that anything would stick to composite, nice to hear PL does.

 

[boatnut74]

Re: Starcraft Holiday Reno and Hull Repair

Looks great! That's one nice lookin Holiday.

 

[Grandad]

Re: Starcraft Holiday Reno and Hull Repair

Next project. I had noticed that the bilge pump was auto cycling more often than usual. On the trailer, I inspected for damage and found hairline fatigue cracks extending an inch or so from the outermost rivets in 4 port side midship ribs. Two of the cracks had actually joined under one of the ribs for a total length of about 5". That rib is at the forward end of the trailer bunk.

At first I beat myself up for not adjusting the bunk properly, but on careful inspection, the bunk was not set too high and the hull was not concave at that point. Hmmm. Something has bugged me for awhile. The aluminum base for the plywood side wall has been angled out at the bottom in this same area, the screws securing it to the floor having stripped out of the plywood. I suspect that the sidewall, when correctly positioned vertically adds significant reinforcement to the hull, but with the base tipped, the unsupported hull flexes more than normal in this area, hence the cracks.

I figured that the only fix would be to put a patch over the cracks and reinforce the hull in this area. You guys know the drill. Out with the seats, the center console, the walls, the floor and the styrofoam mouse hotel. When I took the walls out, I noticed that the original rivets securing the aluminum base to the plywood wall on the port side were a little short and most were broken or had wormed their way into the plywood. Maybe this initiated the flexing of the hull that caused the cracks. I dunno, but if you see yours doing the same, check it out ASAP.

 

[Grandad]

Re: Starcraft Holiday Reno and Hull Repair

Next, the waterless hand cleaner and scrub pads to get rid of the bilge goo. I removed 8 rivets from each of the ends of 7 ribs and would need to lift the ends sufficiently clear of the hull for a 4" x 72" aluminum patch and a layer of 3M 5200. I bent up some 1/4" x 1" hot rolled steel into seven 90 degree "levers" that I inserted under the end of each of the ribs, fulcrumed them on the hard chine and clamped them to the side pocket frame to hold the ribs up off the hull. With the ribs lifted, I was able to slide the 6' patch under all of them to position the patch for drilling rivet through-holes. I also drilled holes at the ends of each crack to stop them from advancing.

 

[Grandad]

Re: Starcraft Holiday Reno and Hull Repair

Next, before applying 3M 5200, I had to build a complex of spacers to keep the patch out of the 5200 as I put it into place. Tedious, but it worked great. With my son's help, we got all new solid aluminum rivets bucked. Got the rivets from Aircraft Spruce. Used the tougher structural ones, not the soft type. One picture shows 5200 oozing through the cracks with the rib temporarily bolted to the hull skin.

To strengthen the hull at the ends of the ribs, particularly in the patched area, I had 2 pieces of #14 gauge 5052 aluminum fabricated into L-shapes 1 3/4" x 14" x 96" long. I installed one on each side of the hull to fit under the floor and behind the walls on top of the ends of the ribs below the side pockets. After filling the voids below the side pockets with styrofoam flotation, I pop-riveted the L to all the rib ends and to the side pocket frame. One picture shows the port side L panel not yet slid forward into place over the flotation.

 

[sprintst]

Re: Starcraft Holiday Reno and Hull Repair

Beautiful work man. She looks great.

I'll try that composite decking myself for trimming.

 

[Woodonglass]

Re: Starcraft Holiday Reno and Hull Repair

Some people are just GOOD at fixin stuff... and you Sir, are one of those people. Excellent Workmanship and Design!!!!

 

[Grandad]

Re: Starcraft Holiday Reno and Hull Repair

When I removed the floor, I discovered that the pop rivets securing the port stringer to the ribs were all broken, except where I had already replaced them where I had access in the engine bay. The stringer was simply trapped between the floor to which it was still riveted and the hull, free to bend sideways as the hull flexed. No support for the hull at all. Little wonder it cracked.

After washing the seams and joints with acetone as recommended by Woodonglass, I painted them with Gluvit. One quart was enough to seal the hull seams at the transom, the hard chines and the stem and with the leftovers to paint the undersides of the plywood floor panels on either side of the engine.

Before replacing the floor and walls, I filled every void I could with flotation. I used only closed cell rigid foam board below the floor to avoid problems with water absorption. I used a combination of foam board types in the walls, based on price and available thickness. I managed to find space to install 35 cubic feet of foam, displacing an equivalent volume of water weighing 2100 lbs. Since the boat, including batteries and some gear, weighs about 1700 lbs, I figure in the event of a capsize, the boat should float at the surface. Since fuel is lighter than water, I haven't included its weight. The minimal flotation provided by any wood structures is also not considered.

 

[Grandad]

Re: Starcraft Holiday Reno and Hull Repair

To avoid a styrofoam snowstorm that I'd get using power saws to cut and shape the flotation, I investigated using a hotwire foam cutter. I experimented a bit and found that I already had everything I needed to make a decent foam cutter. For a power supply, I used an old model train transformer that powered my train as a kid in the 1950's. It has a 50 Watt 15 Volt AC output that perfectly matched the .020" stainless steel safety wire. I even had a suitable 1 1/2" thick piece of plywood left over from a basketball backboard project (that never got completed) to cut for a harp.

I mounted a small turnbuckle and spring on the top of the harp to adjust the tension on the hot wire. I secured an aluminum U channel to the bottom arm of the harp and installed #10-24 rivnuts and bolts every 15 degrees to adjust the bottom of the hot wire to cut the foam at many different angles. I wired the transformer output between the turnbuckle and the U-channel. Clamping the harp in my B&D Workmate provided a versatile workstation. I C-clamped 2x4's to the harp as fence guides for cuts. I spent more time than necessary to build the cutter, but it sure saved me time and a big mess later. If you're considering building one, perhaps an old wooden window frame minus glass would work just as well.

 

[Grandad]

Re: Starcraft Holiday Reno and Hull Repair

Other than the piece under the gas tank that I'd already replaced, the 1/2" plywood floor was in such good shape that there was no need for replacement. Note in the pictures that the old plywood still has the rough splinter edges from the original Starcraft machining. Although many restorers have opted for 3/4" when replacing the floor for additional stiffness, I couldn't justify replacing what is still perfect. Yes, it flexes, but its a boat, not a dance floor. Adding another 1/4" would also reduce the space for the original walls which are still in good shape. I had already lost about 1/8" for the thickness of the L-shape chine stiffener and hull patch. I don't know what preservative was used in 1972, but its still working fine.

 

[Grandad]

Re: Starcraft Holiday Reno and Hull Repair

I was able to purchase Nautolex (Seaway Marine) Sandstone vinyl flooring, but I found no suppliers of Nautolex 88 adhesive in Ontario. The marine store where I bought the flooring said they use 3M 80 Spray Adhesive, but these spray bombs would be too expensive for about 20 square yards. I did buy one $40 can to use on the side pocket liners, but it only did one side. As a substitute for Nautolex 88, for the main floor area and the forward sidewalls, I used Ducan Dek-Master vinyl decking adhesive from HD.

Of all the stages of this project, the one that most intimidated me was putting down 12 lineal yards of flexible material costing $30 a yard with contact cement. Contact cement! My experience with contact cement is that you get one shot at aligning two contact surfaces that can't be re-aligned or even pried apart after they touch. I experimented with scrap pieces, seeing what would happen if I applied the Nautolex while the cement was still wet, rather than wait the prescribed tack time. My thought was that if it's still wet, I could reposition or get wrinkles out of the fabric. Then, given sufficient time, the cement would still dry and hold adequately. Wrong. My test showed that although the cement did dry over several days, it's hold was nowhere near as good as it was when proper tack time was observed.

With the foredeck and the engine still in place, I needed a good plan. First, having rough cut the Nautolex, I stapled it along the port edge only so it would hold in position. I cemented the starboard side only from just under the dashboard back to the engine bay. I was able to drape the vinyl on overturned refuse recycle bins to roll the cement on the underside. After the proper tack time, with 2 helpers, we carefully spread the vinyl in place without wrinkles. We repeated the process for the port side, then under the foredeck and then each side of the engine. I was a relieved and happy camper when it was all stuck down.

 

[Grandad]

Re: Starcraft Holiday Reno and Hull Repair

Re-installing the walls turned out to be easier than I expected. As mentioned earlier, many of the original rivets securing the aluminum base to the plywood wall were broken or too short for the task. I couldn't find long enough rivets, so I resorted to using #10-24 bolts, small fender washers and Nylock nuts instead.

I knew the port side wall in particular would be tight. With a little help from my "handraulic" jack, things went pretty smooth. To get the walls in place, the inner edges of the gunwales had to be jacked up to allow enough space for the walls. Fortunately, I was able to remove 4 stereo speakers that were conveniently located at the exact points I needed to jack the walls. With the jack angled into the top of the speaker holes, I was able to lift the gunwales and the walls easily moved back into place. I had previously extended my 2 ton bottle jack with a piece of 2" schedule 40 aluminum pipe and a 2" solid cylinder of aluminum.

 

[Grandad]

Re: Starcraft Holiday Reno and Hull Repair

The standard doghouse always seemed oversized for the 4 cylinder engine and wasted space whether it was open or closed on the floor mount piano hinge. When doing engine service work, it really was the elephant in the room. The jumpseats on either side never seemed to hinge properly, tending to bind somehow and occasionally would dismount themselves. I feared losing one while trailering. The spaces behind them were occupied by twin batteries on one side and gas tank on the other, neither location suitable for additional cargo. I also found we needed a place to change and to use a portable toilet, so after taking measurements, I rough sketched changes that would give us what we needed and then precisely modeled the entire plan in a 3D CAD program to ensure it would work.

Moving the batteries to a point directly in front of the engine freed space on the starboard side for a pop-up change room. Twinning the 2 jump seats as a loveseat bench in front of the engine and above the batteries created additional storage space in front and above the portside gas tank. Relocating the batteries meant that the battery selector switch needed a new and easily accessible location. I chose to put it in a control panel below the center seat along with a fuse panel and the ON/OFF/AUTO bilge pump control. Access to the top of the engine and storage area behind the port seat would be via hinged lids.

The design looked a little radical, but it worked (on paper anyway). Of immediate concern to me was access to the engine for maintenance and troubleshooting and access to the bilge and bilge pump in an emergency. I determined that using only hand screw knobs, rather than tools to secure the major components would ensure simple and speedy access. The structure had to be strong and stable enough to stand upon, yet not be dependent upon rigidly glued joints, since a boat is always flexing. I would use glue only to laminate two 1/2" layers of plywood for the horizontal compartment lids, strong enough to dance on. The rest of the structure depends upon aluminum angle bolted to 1/2" plywood partitions.

 

[Grandad]

Re: Starcraft Holiday Reno and Hull Repair

First, I cut out the floor directly in front of the engine to position a pair of Group 27 deep cycle batteries recessed a few inches below the floor into the bilge. I built a frame to firmly nest 2 battery boxes clamped down by a sturdy piece of oak contoured to fit the tops of the boxes.

In front of the batteries and above the floor, I built a wood and black plexiglass enclosure for the battery selector switch, an ATC fuse distribution panel and bilge pump control. There is sufficient length of wire and cable covered in split loom that the battery boxes and control panel can be lifted out as a unit and rotated to sit on the floor out of the way of major engine work while still remaining functional.

 

[Grandad]

Re: Starcraft Holiday Reno and Hull Repair

I secured aluminum U channels are to the floor to guide the bottom edges of a plywood partition wall on the starboard side of the engine and a storage cabinet surrounding the gas tank on the port side. I avoided using glue, preferring to bolt things together using aluminum angle to allow some flex yet still remain strong. I disassembled the jumpseats from their tubular aluminum frames and re-mounted them together on a single upholstered plywood frame as a "loveseat". The loveseat assembly mounts port side of centre above the control box, batteries and a storage space.