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My last blog about Flats skiffs set off a good thread on the Micro Skiff site called "Name that skiff".
In my blog I used 2 unnamed pictures of a new skiff build I had seen on my FB page using two photos to illustrate my feelings towards what I feel is a trend of some companies today in boat building.
My statement was " this is old school boat building". This got the skiff world talking with questions of what I meant and people saying "how dare I !" I do not have an agenda against this company or any of the others, it's just that I was one of the developing forces in the designing of the building process that this company still uses today. I want to explain here why my past thinking is today's "old school building."
I do put my foot in my mouth from time to time. I feel it was worth it.
I will explain my thoughts now. To do so I will have to go over a bunch of terms with my personal thoughts explained along the way. Please consider again that this is just a personal blog of my writing of what's on my mind going from my head to Cyber paper. I share my thoughts in the hopes that some might get ideas to add to their own.
Today finds me with my wife Rachel, our daughter LIllian and our sea dog Bequia onboard the Hogfish Maximus anchored behind a mangrove island in Tarpon bay 11 miles up the Shark River in the Everglades National park for Christmas. Today is Boxing Day and as Rachel is Canadian we have had our special meal for noonday. It was supposed to be a concoction similar to the American "Turduckin" with my idea being to substitute the birds with a caught Python stuffed with Racoon that was stuffed into an Alligator,
Calling it a "PYCOONATOR ".
We ended up with a " Kieleppertato" instead.
I will start with SKIFF TYPES
FLAT BOTTOM skiff designs built in wood, solid fiberglass or aluminum are the basic skiff hull builds.
In wood they can be quite elegant being built in plywood or plank construction. These skiffs range from the simple elegant Bateau to the plywood beauty below built in stich and glue.
Built and designed by Morten Lovstad in Texas. She weighs 550 lbs.
If built in solid fiberglass these skiffs will need molded in stringers in the hull design or inside the hull to stiffen the flexible fiberglass skin. These can be heavy boats by today's standards but can last forever.
If built in aluminum then there are many different ways to go from simple mass produced skiffs with their inside hull reinforceing frames and ribs to keep the whole shell together. There is also the bent shaped welded aluminum hull that is similar to stich and glue hull shapes by designing your hull around a developed surface of the aluminums panels. With these hulls being all welded together you end up with a monocoque built skiff that is very rigid compared to their simpler sisters.
Build in any of these methods using too thick of planking and you just end up with a heavier craft.
ROUNDED HULL BOTTOMS go way back to the beginning of boat building. Starting with Carvel constrution all the way through to strip building, and cold molding hull skins.
These shapes can be very stiff if designed properly from the inside and because you are building in wood they too can be built into a Monocoque hull making them very strong, stiff and rigid.
This hull was built in Novia Scotia over 30 years ago and was then brought to the Florida Keys by Ted Williams along with 5 other bare hulls. This hull has been in this family since they acquired it from Mr. Williams many years ago. They hired Geneo Baker to make her new again last year. Geno showed me a sheet of paper their grandfather had kept of all that had been done to her and by who over the years. I'm on that list back in 1986 having repaired and glassed the bottom and stern, installed a "cored hull floor" and other work. See that spray rail. I noticed that back then.
Look for CHALLENGER SKIFFS, WIND RIVER SKIFFS, FIBERCRAFT, and other classic hulls.
VEE BOTTOMS
Vee bottom skiffs and boats have been around from the days of sailing till the era when engines took over sail. What happened was in going from sail to motor the curve of the hull bottom started to straighten out to gain the speed that could be had by ever more efficient engines.
Today just walk under any boat barns boat rack and look up at all the vee bottoms. At first glance they can all look the same but as you delve into design and skiff history you can pick out the good ones from the average ones. It's the details. Today there is still ongoing vee bottom development and improvement using the new materials of today along with the possible construction methods in conjunction with modern engines.
As a shallow water skiff designer you have to weigh all the pros and cons of these bottoms if going with one in your design.
THE PROS
- Allready well proven track record and very easy to not go wrong.
-Depending on dead rise... That is degree of vee they can give a good all round ride and be comparatively dry when running.
- They look "normal" so it's easier to sell to people that are just used to looking at what's already out there.
-They can be the fastest bottoms for the need for speed group.
- They look good
-They can be very quiet hulls when poling if their Chines are under water.
CONS
- They have a chine that most all times runs up and out of the water causing noise for the ultra quiet fishing group when poling. The SUPER SKIFF, HPX, MAVERICK SKIFF, and the CHITTUM SKIFF have below the waterline Chines eliminating this noise problem.
-Some vee designs with lifting strakes can be a bit harder to pole than other designs with its deep vee dragging water eddies as you pole along.
Two of today's modern vee designed skiff hulls with their forward Chines staying under water at rest.
The CHITTUM SKIFF shown here. Look for HEWES, MAVERICK, PATH FINDER, WILLY SKIFFS, DRAGONFLY BOATS, PIRANA BOATS, SILVER KING, MAKO, EGRET BOATS and many others that have standard vee bottom thinking. All great looking and working skiffs until you get into the super shallow no noise easiest to pole along discussion.
HYBRID HULL shapes.
This is the skiff I designed and built 2 years before Hal Chittum asked me to design the WHIPRAY.
This is a hybrid hull as it's taking in some of the rounded hull shape of the Novi skiff shown above, has a below the waterline chine for lift, and upper spray rail chine that molds into the hull topsides and a reverse spray strake to help deflect the mid hull spray back down into the sea. The pocket was to get the engine up higher for shallower draft in running which it did, but caused too much poling drag to be worth the compromise.
Today the flats skiff world has a very good selection of hybrid skiff hulls. Look at these builds, BOSSMAN, EAST CAPE, BEAVERTAIL SKIFFS, DRAKE BOATS, CAYO SKIFFS, SPEAR SKIFFS, ACTION CRAFT, YELLOWFIN SKIFFS, HELLS BAY as well as many other home built designs.
I feel that the WHIPRAY design had a hand in leading the way to more out of the box or unconventional way of thinking, designing and building a flats skiff to today's technical skiff world. It's all been good. What made it work was its light weight build and engineering along with its hybrid hull design. I am proud of having played a small part of this new direction in skiffs.
Now to the PROS of these hulls.
- Because they follow no previous rules of convention they can be quite good at doing what is asked of them if they "get" it right.
- They can be dryer running craft from spray.
- They can pole easier if weight is part of the design build.
- They can be the shallowest craft for poling if designed and built right.
-They can be very quiet poling craft in varying conditions.
- They can ride quite well considering their light weight and flatish bottoms if designed and engineered properly.
CONS
- Because they are not conventional designs they look unconventional so can be odd looking to the old school traditional way of boating. This I have tried to blend so I have in my designs tried to mold new and classic together to get a look of " that looks right". It's very hard as I love classic but live in the present. In my latest LITIHUM design I have said to hell with looks lets just go for what I hope will really work well for the lets stay as dry as possible, go as fast as possible, pole as shallow as possible, and stay as quiet as possible for today's spookable harassed fish and hard core fishermen. We will see soon enough.
- Their bottoms are not the most efficient for speed so can be a bit slower if built too heavy and not designed to get the most out of speed but still keeping the shallow draft aspect and being as easy to pole along as possible.
-They can slide in a fast turn if not knowing how to drive to over come this possibility or by giving up a bit of draft for a keel.
- If built too heavy then you have spent money on a product that is not performing up to its potential as advertised and can be wetter running because of this weight gain.
NOW YOU HAVE TO CONSIDER THE FOLLOWING WITH ALL THE ABOVE.
Ultralight construction
Semi heavy
Heavy
ULTILIGHT
Let's take a skiff I know very well; the WATERMAN in its original design concept and construction.
The WATERMAN was my idea to have a price point skiff to sell to the consumer that could not afford the WHIPRAY.
The WATERMAN concept was to be a bare bones skiff with just a foredeck and two aft boxes to sit on with the battery inside the Port Seat. ( the WATERMAN IS THE SAME AS A WHIPRAY HULL, AS IS ALL THE GORDON WATERMANS IN BOTH THE 16' and 18' VERSIONS. THE SKATE, MOSQUITO LAGOON ARE JUST NAMES GIVEN TO WHIPRAY HULL BUILDS. ALL THE SAME BOTTOM BUT DIFFERENT INTERIORS.) The WATERMAN and the others under the different names were designed to be built with fiberglass Matt and Roving with core only on the bottom of the hull up to the upper chine and in the bow and stern boxes. These skiffs were very light with this build at 300 lbs. They to me were the best bang for the buck for someone who wanted to move up from a jon boat. These skiffs ran great but because of their open construction they could bang about, twist and were in no way the same ride as the WHIPRAY.
When I hear people compare their WATERMAN to a full deck skiff in ride I know they have very little on the water skiff experience. The WHIPRAY in comparison is a yacht and as they say in the Bahamas
"Can take it".
To have a very light skiff work to the fullest it has to have all its design components all put together properly to function. With light weight, you need a stiff and monocoque hull that will not give and move about like a screwed on deck that is not bonded to the hull. You have to look at the target weight of the size of the skiff when built, loaded and used. That is if you have a very light skiff with nothing inside in calm winds she will fly along and pole like a dream, but when the wind picks up it could be hell to pay to pole and cross that bay back to home.
It's a compromise that has to be thought out in advance of how and where you will be using this craft.
To me a WATERMAN at 300 Lbs with a 25 Hp two stroke is a great all round light weight goal for semi protected waters for boaters on a budget. To get across a bay in big chop and wind it will not be fun but doable. This skiff and others like it can take it.
It comes back to the saying..."People take boats places, it's not boats taking people places"
Now take the exact same hull the WHIPRAY weighing in at 395-410 lbs with the same engine, its full fitted deck and cockpit and its a whole other world of total stiffness absorbing all the chop and away you go.
Go to the next level with a newer skiff design of today with a bit more vee and well.... Let's talk the ULTIMATE SKIFF CHALLENGE.
Skiffs that I think fit into this category
Some old and newer HB designs, Some GORDON skiffs, SPEAR Skiffs, CHITTUM Skiffs, GENOES, CAYO SKIFF, some small EAST CAPE designs, MITZI SKIFFS, detailed SUPER SKIFFS being poled by people that know how get them as shallow as possible and my guess would be the ANKONA SKIFF and others that fit into this category.
DISCLAIMER .... I really only feel comfortable talking about boats I really know well. Lots of the skiff builds I mention I only have an idea of how they are built. I get this basic knowledge by looking them over when I come across them in life and from the many pictures people send me when asking advice on how to repair something with their personal skiff. Here I get to see lots of open Heart surgeries taking place.
SEMI HEAVY
With today's knowledge of what "can" be built then I feel I can put forth the next 2 weight categories.
This is just my version of a guy that likes designing skiffs and looking at things so take it as just one mans personal view.
To me today if you have a skiff that is sold as a technical skiff and bought to fish in shallow water, be easy to pole, be very quiet, run in most inshore-nearshore conditions with confidence, and be a top quality build then you should be in this list.
Your skiff hull before bolting on the engine if between 16'- 18' should weigh no more than 650 lbs., draft no more than 8", have speeds in the upper 30s to the mid 40s without using high HP, be comfortable to ride in most protected bay conditions and pole along straight without too much effort in cross winds to down wind conditions. Only good friends are going to want to pole you upwind for long periods.
There are many skiffs built today that should fall into this weight class. I will let you make this list.
HEAVY
Here goes, to me the heavy skiffs of today are the skiffs of the past including all my first builds back in the 80s. These are skiffs that weigh more than 650 lbs. My Mako redesigns back then that became the SILVER KING SKIFFS weighed in at 750 lbs plus with the KEVLAR SUPER SKIFFS I built weighing less but by my standards of today way overbuilt.
So for this category if your skiff is in this weigt class it is heavy. This is not a bad thing by any means. Your ride can be very good due to the weight your engine is pushing along through the chop. It will feel way more stable at rest. It will not be much fun to pole if you don't do this lots anywhere but off the wind. It will be a great all round skiff for those that are not TOTAL SHALLOW WATER, NO NOISE, EASY TO POLE PEOPLE.
So rest at ease, I feel you are in the majority of the crowd that is reality.
I believe that your reality is that you would like to be able to get into shallow water at times, but you have kids, two big buddies, a wife and all, so what you want is an all round skiff to just get out on, and give you the chance to be a contender.
Just think.... there are most likely less than 2000 HBBWs skiffs ever built ? maybe 800 EAST CAPES ?
100 CHITTUMS ? 150 SPEAR SKIFFS ? and so on down the line with the total number of totally dedicated shallow water hard core enthusiasts out there on the water in the maybe thousands at any given time than in the many thousands.
Today, going up the Shark River, I have counted seven skiffs; three HBBWs Marquesas with two having 3 guys in them. One with a couple. One was a SHALLOW CRAFT with 3 guys, two were vee bottom craft with 3 guys each, a real nice 20' power boat with 2 guys, and a Maverick HPX with 2 guys. All looked like they had put in at Flamingo and made the 25-28 mile trip.
If you were to include all aluminum skiffs, Jon boats, Scooter boats, Carolina skiffs and on down the line then yes there are a bunch of shallow water enthusiasts out there but here we are talking about dedicated flats skiff designs.
BUILDING TYPES
There are many categories of skiff building, here's my look.
SOLID SKIN HULL, SCREW ON DECK
These types of skiffs are what I term old school but very proven builds if done right.
Some of the skiffs that fell into this category in the past would be the HEWES, MAVERICK, PATHFINDER, ACTION CRAFT, SUPER SKIFF, SILVER KINGS, CUDA CRAFT, SHIPOKE, DOLPHIN SKIFFS, and some of my early 80s builds. These skiffs could be very heavy by today's standards but still make great skiffs. They will not fit into my idea of the technical skiff world though.
PRODUCTION SKIFF BUILDS
99% of what you can buy is a production built skiff. It's a boat made from a set of molds with very little ability from the builder to modify. To modify skiffs in a custom way in a production shop is hard as it takes a different skill set to do these modifications. Lots of shops steer away from this because of this. If a person is good enough to build anything on site they normally work for themshelves. But I have been seeing lots of shops now doing custom work and repairs to fill in during the slow times of new skiff sales.
I aways had custom or repair work on the side when Lawanda and I had BACK BAY BOATS in Key Largo to make sure we always had cash flow coming in.
These skiffs can be built to the highest standards but you have to know what you are after to find the right shop to buy your skiff from. All shops build skiffs that will last many life times if cared for in a reasonable manner.
The most successful person in skiff building has to be Scott Deal with HEWES, MAVERICK, and PATHFINDER boats. The rest are just a fraction of the numbers with my guessing to ACTION CRAFT as the next in line. I don't include Bass Boats here at all.
Here's a SUPER SKIFF ONE OFF build of mine that was built in 1985 and is owned by the original client. He has taken very good care of this skiff over the years.
Different owners but hey this skiff can be brought back to life.
TOP END PRODUCTION MARKET
Now we are in part of my past life. Catering to the very detail orinented crowd of clients. I oversaw the building of over 300 skiffs from 1997-2002 while at HB. At that time the boat company that had the best details were the EGRET line of two skiffs. Just fantastic tooling and detail by Jim Gardiner as master builder.
Today on sites like MICRO SKIFF you can get all the opinions and advice you want all day long from a myriad of experts all talking behind a made up name.
Most of it is very good information, but you have to wade your way through this. If you are new to the sport, to me, it would be daunting.
With this in mind please don't take what I say as gospel, do your own research and form your own opinion. There are lots of ways to get to the same end.
What I did at HBBWs is to design and engineer a way of building very lightweight skiffs at that time which have stood well the test of time.
NOW when I see a picture of my old shop that is still using the same process, build method and techniques that were developed under my leadership back in 1997-2002 and by just looking at a picture of a skiff build online today that is below my standards then I feel I can say "hey that's not what I would do".
I will explain what I see and why I felt I had to bring this standard of build up.
Not all skiff builders are falling into this realm. All it takes is to just ask around from people that have owned and run various skiffs over the years. Go to the various repair-renew shops around and ask what the difference in weight is of an old hatch weight compared to now. It's enlightening but not to some of the new parts at hand.
As I sit here writing with the mosquito screens in place on HFM, I am listening to the Mosquitos all complaining about my force field. We are anchored in Tarpon Bay 11 miles up the Shark River and sure enough the Tarpon are rolling about outside now.
ONE OFF SKIFF BUILDS
Here we will touch on the subject of those lucky few that build their own skiffs or have a new one built for them. This kind of boat is few and far between because in today's world not many people feel they would have the skills to build a seemingly complicated skiff design on their own. They also don't have as much free time to devote to the 500-600 hours needed to build one. The other factor is the cost of having a skilled builder build one for you. It can be as or more expensive than a store bought one to order a one off skiff. But to build a one off on your own will cost around $ 8,000.00- $15,000.00 in materials less the engine depending on the design, build type, and interior. So a huge savings factor if you have the time, space available with very modest skills.
I don't have any desires to build production boats again. My future AGENDA is in selling a few how to build plans of my designs to home builders and to maybe get some new design work. This kind of work I can do where ever I am on my sailboat in the world now with the right understanding clients. So far so good as I have a few new design commissions I'm working on now and will be ready to start shipping out some skiff plans sales next month.
I get more inquiries for shallow sailboat designs than powerboats. I like both worlds so good for me.
NOW ON TO THE BUILDING TERMS
Here I will explain the way I SEE THESE PROCESSES. THESE ARE MY PERSONAL OPINIONS.
I WILL BE VERY BRIEF HERE AS IT WOULD TAKE A BOOK TO BE ABLE TO GO INTO DETAIL.
-LAYUP-SKIN COAT
After spraying in the hulls GELCOAT onto the molds surface you let it cure. There is a time frame for optimal curing and then laying on what is called the skin coat. In my old school days it was when the gelcoat felt it had cured-hardened enough to the touch to accept a layer of 3/4 oz. fiberglass matt cloth wetted out in resin with a short nap haired roller on a cage handle. I sprayed first thing in the morning and would be skinning out before lunch. When rolling out you would lay on a wet layer of resin over the gelcoat, then lay the precut matt cloth over and then using the dryish roller roll over the matt cloth soaking up the resin and impregnating the matt cloth. If when this was done you had a spot or area that was still a bit more dry you would then dip your roller into your bucket of curing resin getting a bit more resin on your roller to finish the job. Training people how to do this has been a big part of my life so I can go and do something else in the shop. This is where the details start.
What I want to see is the matt just wetted out. Move around and come back to dry spots later as it takes a bit to soak up the resin. Once it looks just wetted out you now get out your hard roller with little groves in it and proceed to roll over all the matt cloth to squeeze out the air bubbles that are in the matt cloth resin layer.
During this process any place that looks a bit thick with resin you can roll over and wick up with your dry roller. Having a sheet of cardboard nearby is good to get the resin out of your roller. You can use the excess resin on the next section. You NEVER leave excess resin on the part being built.
Once all is hard rolled out and has a uniform dull look with no shiny pools about in the corners or in the channels you move onto the next section.
This is tedious work. It requires skill and a daily conscientious attitude of wanting to do your best for your personal pride and for the product you are building.
This is the first step in building a skiff.
Once the skin coat is on and cured your hull gelcoat skin is secured and pretty hard to mess up. Now you can if you have a very detailed hull bottom with short sharp Chines and edges lay in strands of cloth into these sharp edges to be wet out. In deeper areas a putty mixture is applied to help the following layers bend, flow and lay down well as you lay on the next layers of cloth and core.
If you are doing old school as I see it today and are laying your hull-part up by hand then every layer needs the same amount of attention to detail. NO excess resin. It adds weight and can make the part brittle in time as the resin cures in the sun. Today you would use a resin gun that sprays the resin out at the pre determind catalyst ratio which is so much faster, accurate and easy to do in skilled hands. No more buckets and stir sticks. This is a very good way to build a skiff today under skilled leadership and skilled hands.... But it's OLD SCHOOL to me as you have to rely on laminators and shop formen to make sure it's done right so the parts come out and weigh what they should and not be resin rich. By laying up a part willynilly with no regard to resin content, extra cloth weight, cloth being applied in the wrong order you are just building a part. Not a part that will be part of a well thought out designed and engineered process.
35 lbs of the wrong cloth and resin in one wrong hull skin adds unnessarly weight.
Now we can start looking at the rest of the build. Why is Kerfed core foam being used in vertical bulkheads? All that extra resin in those kerfs add unnessary weight and no added strength. Why so much bonding putty? I can go on. The dilemma I see is that these skiffs will never come apart.... But they will weigh way more than originally designed so will not be performing to their original design goals.
NOW IF you are building in the PRESENT DAY and will be INFUSING your part then you now are ready to lay in the dry layers of cloth and core. THIS IS TODAY's STATE OF THE ART TECHNOLOGY TO ME.
VACUUM BAGGING... WHAT IT REALLY MEANS
ok here it is.. Vacuum bagging is really just a big clamp, a very strong pressure to hold down materials.
When you are "bagging" a part, a hull skin, a foam core panel you are using an air controlled Vacuum that sucks down a sealed plastic membrane over your part to a certain pre-determined level of weight per pounds per square inch to hold all your pieces together till they cure.
That's pretty much it. No more lead pigs, concrete blocks holding the unruly core down. The whole thing can be just squeezed down and held in place pretty much perfectly if you know what you are doing.
Before this I used to skin the hull out, then let cure. Then I would cut all the core for the hull by hand with a razor knife. I would lay the scrimed core down till It laid in naturally without pressure. All the pieces would be marked so when removing it would then be easy to remember where all the pizza shaped pieces would lay. The hull skin would now be laid in and when wet and all hard rolled out the core would be added on top having been wetted out with resin with hand pressure. With simple hull shapes this is still a very strait forward way to go if building simple boats. But to get to the next level you now go to bonding puttys, bagging and if at the top end you INFUSE.
VACUME BAGGING DOES NOT SQUEEZE OUT EXCESS RESIN...
IT DOES NOT MAKE SLOPPY RESIN WORK BETTER BY SQUEEZING OUT THE EXCESS RESIN.
IF THERE IS TOO MUCH RESIN THERE TO START WITH YOU..... DONT.....KNOW.......HOW.....TO FIBERGLASS PROPERLY TO START WITH.
If bagging is done properly it can apply a nice uniform pressure to a well laid up cloth panel to give a better more even laminate. Like over a one-off hull. BUT you have to be at a good skill level to make this work to start with. Trust me... If you laid up fiberglass alongside me for a couple of days you will get it and be on your way to a new career. Those that didn't, I let go.
If you apply too much pressure when bagging a core skin it will squeeze out all the bonding putty out from the layer between the core and the hull skin you are wanting to bond. It takes knowhow and conscientious skill to do this every single day in the shop. It's just a process that has to be followed every single time correctly.
When I race on sailboats it's all about the process. Be sloppy you lose the race simple as that. I Just spent the last year and a half as part of a twelve person crew racing in the Caribbean regattas on an all carbon 38' sloop. We won or lost our races after 3-5 hours of racing by 3-15 seconds or less.
ALL GREAT BUILDING STARTS WITH GOOD BASIC HAND WORK.
START SLOPPY END SLOPPY.
INFUSIONING BOATS AND PARTS
I feel this is TODAYS way to build a top end skiff. FIRST OFF IT IS ENVIRONMENTALLY FRIENDLY. YEA!!!!!
In this process you do not let out any Styrene into the atmosphere so this is good. It's all contained in the Vacuum bag that is covering your resin.
I believe that EAST CAPE SKIFFS were one of the first new skiff builders to embrace this technology. EGRET BOATS was from the beginning long before HB started up. Hal CHITTUM with his quest to stay at the top end has run the gamut of ways to build from preimpregnated Epoxy cloth post cured resin and cloth to Infusion of Vynelester hulls now.
What the basic process is if you are building a polyester resin hull you spray in your gelcoat and lay in your skin coat as described above. Once done you can then lay in all your dry hull skin cloths into the mold with the core on top and then your final inside skin layer on top of it. All dry. You have all the time you want to make your bed nice and neat.
Now you lay your vacuum Infusioning bag over all this. This is different as you will be sucking all your resin from pre catalyzed containers through many tubes that are spread through out the plastic sheet membrane that encompasses the mold. These all have to be airtight. The bag edge can not leak. You can hear the pinhole leaks with a head phone listening device. Once set and sucking away with the knowledge of shop temperatures, resin temps, hull temps, cure times and ratios you can then catalyze the resin to your math and watch it get sucked into your hull or part like an evil movie.
Well this is the simple version here.
There are lots of things to consider depending on the size of the part, complexity of moldings, cloths being used, temperatures and so on. Now that the resin is flowing through you have to know when to stop.
There is no bell that rings telling you your cake is done. It's a process but when it's done right it's the best process for today's technical skiffs. Ah, well when there's no resin left in the bucket then maybe it's time sit back and watch your part cure.
What you get is a skiffs parts that are built using NO bonding puttys as the resin is sucked through all at one time bonding all together at once. Weight savings and all is bonded together at ONE time so no secondary bonding of hull lay ups taking several days.
The added bonus is there is not much overhead in the materials needed and waste afterwards.
The best part is no bending over a smelly hull mold rolling out fiberglass cloth by hand wearing rubber gloves with your sweat dribbling out and down your arm. To me it's a no brainier. It's today's technology.
The best technical boats built in the world today build using this method. They don't hand layup.
EPOXY RESIN VERSES VINYLESTER RESIN
Epoxy resin is by far the best resin for many applications if needed and cost is not a factor. I can write a few chapters on using different resins and materials but let's just say that epoxy is very good.
I like working with it because it has no Streyne smell, can have plenty of working time with the right catalyst and brand and has many different cure properties that I like. But it costs.
If you are infusioning a boat in epoxy you are stuck with having to paint the part after being built as there really is no good way to bond epoxy to gelcoat. They say "oh yea my product works." Good, guarantee me it for 20 years. "What!?"
Painting a skiff properly takes as long as building one and very expensive if you are having to pay skilled labor to do this for you. It's hard to sell a top end skiff not using what is perceived to be top end products like AWLGRIP paints. When home building you can buy as good or better automotive paints for a fraction of the costs. You can't sell a $70,000.00 skiff not using the so called best stuff.
When infusioning a skiff in Epoxy or Polyester it's virtually the same time in the build process. It just comes down to resin costs. That's it.
POLYESTER RESINS
So many to choose from. All depends on what type of design you are building. Such as a river Canoe bouncing over rocks to a light weight Flats skiff that wants a resin to have good memory when laying against a foam core inner hull laminate. What I am describing is a type of Vinylester resin that can be bent to 60% of its shape and spring back... Many times in conjunction with the core. You will never do this much to your skiff but bouncing off of logs, limestone ledges and such, this pairing will help.
If for instance you had a general purpose polyester resin in your layup with a very hard core you could end up with a bunch of crushed dings and dents in your hull bottom. When you read the word Fiber- Glass, that "glass" part can break.
In order to make it all work for the best then talking to your Resin supplier is the first start. Someone like a Gene'o Baker. He has built boats with his own two hands so knows what really works. He has seen it all because he has been to every shop at one time or another. When I get around guys like Gene'o I just try to garner as much info from them as possible to add to the back of my brain. It's lots of fun realizing how far down I am on the knowledge curve when around these experts.
When building boats these guys will come by for free and dispense info, advice and such. But when they are salesmen they are looking to make a sale. They all have helped me many times when a well known product they sold me was not working as per it's technical stats. They know where to go and how to proceed. I am not a chemist, just a boat builder.
For me if building a one-off skiff and you were not on a real tight budget I would build in epoxy resin from the start because of the virtual no smell factor. This will help keep things at home happy if using your garage. It's very forgiving to work with if using the right brand. All epoxies are not created equal.
If price matters then there's nothing like polyester resin and just deal with the styrene smell. Polyester cures quicker so you can do lots of things in one day. It too, if understood, is very easy to work with.
The only difference in an epoxy verses a polyester built boat in cost is the resin. All else stays the same.
If building a 400 lbs skiff in core you might use a total of 20 gallons of resin.
Epoxy retail is $1700.00 with the brand I would use for 20 gals.
Basic Polyester retail is $ 400.00 for 20 gals.
Both can be bought wholesale for less.
My last boat building project was an all cored epoxy skinned trimaran that I had to cure in an oven for 4 hours at a temperature of 120 degrees for the brand of epoxy I was using to achive its final hardness.
It also helps precure for shrinkage in cloth printout later for the finish paint job. Sheesh what a job building an oven around a 32' sailboat and cooking it in a day and tearing it down the next.
This boat is one of the strongest hulls I have ever felt in stiffness. Amazing... But boy is she jumpy. So taut and non giving. It's what she needs for racing but not for fun to be aboard.
The same can happen in a small skiff if not planned for in advance.
CLOTH TYPES
I will give a brief description of the basics of cloths used today and what I think of them personally. It's personal to me as I have worked with all types over many projects so I have a good rapport with some and others I just try to avoid. They all work great if used in the proper way or by just using common sense.
Today there is a large selection of cloth weights and types to choose from. I will just talk about the basics here now, and give some opinions from my exsperiences working with them in both building and repairing boats of all sizes.
FIBERGLASS MATT
Look at the first drawing with its scratchy hash mark rendering. The thin line next to it shows its finished thickness when wet out with resin. This is a 1-1/2 oz. Matt.
All Fiberglass cloths in both E-Glass, Arimid, Carbon, and S-Glass all come in different cloth weights. They all start their life out as one long strand rolled up into a round wheel shape. From here they are woven into all the many weave types you see today.
FIBERGLASS MATT is composed of many short 1-1/2" lengths that have been chopped off this roll and pressed and glued with a binder to form a flat sheet of cloth. It comes in several weights and thicknesses. If you are building a boat with a "CHOPPER GUN" you are using a gun that sprays out precatalized resin into the chopped off strands of E-Glass that is being rolled off and chopped off this round spool onto your part. Linger too long in a spot and you have a thick layer to hard roll out. This is old school building but if used with a knowledgable operarator it's the back bone of the boat and fiberglass industry. It gets this material onto the mold quickly. Go look at Geeno boats.
MATT is used as a filler cloth to hold resin and be a place to lay your woven cloth material onto. Both are then hand rolled with a hard roller with grooves in it to squeeze out air bubbles and to help wick out excess resin.
MATT has very little strength as its fibers are very short which means it has to be used as it was originally designed as the underlay of a woven cloth. It's ok to use as a moisture barrier on a plywood deck at your house but not as the last layer on a boat.
On light weight skiffs I use it to "tab" in bulkheads and interior parts as these are all inmoble and in compression.
It's a huge waste of weight, labor time, money and no strenght gainings if used as the last layer in a boat build anywhere.
FIBERGLASS STRANDS
The next drawing illustrates the size of the strands of the beginning of a cloth materials life. These can be used in a single length to lay down in a sharp molding edge to be wetted out and make that edge very strong. The only time you buy rolls of material is if you own a chop gun. Otherwise to get a strand you just pull one out from a layer of your cloth. You do the same thing when you want a straight edge line to cut your cloth with scissors.
CLOTH SIZES
This sketch shows the relative size and weight of regular E-Glass cloth.
Carbon fiber, KEVLAR, S-Glass can all be woven Into these and many other cloth weights.
This type of woven cloth can be very easy to work with both in designing and in building by hand.
I like the way they can be used in conjunction of a Fiberglass Matt underlayment. Most all my past skiffs have been built with a combination of these two cloths.
If you lay up a single layer of 1-1/2 oz. MATT on a waxed table and let cure it will be very easy to bend and break in half when removed from this table.
If a layer of 7oz. Cloth was added to the MATT. It would bend over 60 % off its original flat shape before it would fracture.
If CARBON cloth was added instead of the E-Glass cloth then it would be very hard to fracture. But it would.
If KEVLAR was added using the right resin that KEVLAR needs it would just bend with the MATT slightly fracturing a bit when bent into a full circle. And it would return to 80% of its original shape.
This is just a sample of what can be achived with different types of clothes.
BI-AXEL AND TRI-AXEL CLOTHS
These cloths are simply strands of E-GLASS cloth that are laid at varying angles and numbers on top of each other with a light thread weaving them together. Some have a layer of 1-1/2 oz. Matt bonded to this weave too.
They come in many different types of weaves so you have to do your research to use the best for your project.
The standard B-AXEL cloths I find to be suited to larger boat construction for quick build up of skin thicknesses. I find that in hand layed up hulls and parts that you get lots of air in between the strands of cloth that is almost impossible to roll out. Also because the whole cloth weave is all stitched together it will not blend and flow well into complicated hull and boat moldings. Because of the air in the weave, the added resin needed to lay these cloths down by hand I never use them.
I have repaired many boats with this type of construction and I find these hulls to be quite brittle and easy to fracture. A typical hand layed up B- AXEL hull skin that is punctured can be pulled part by hand stripping huge chunks of the hull laminate away. Because of this and many other first hand exsperiences I stay away from this cloth in hand layup builds.
NOW use this cloth in a part that is being INFUSED then to me it's a different story. Because the skin and all is being infused with the resin under great pressure you end up with a great resin to cloth mixture. Different world now.
This has been just a glimpse of what modern boat builders and designers have to choose from and work with.
Ok enough... But
To summarize, I still feel that details matter when you are at the top end of the market chain in skiff building.
In my personal life I live on a plywood bulit sailboat that I designed around the motto of...
"THE NORTHE SYSTEM"
NO
OTHER
ROUTE
THOUGHT
HEAVY
ENOUGH
Another world, different discussion
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