5
Fabrics
The term ‘canvas’ is used to broadly define all the fabrics associated with a boat – from the sails, to the external fabric biminis, covers, cushions and all the other miscellaneous, pouches, containers, covers, bags and organizers that are found on boats. Most fabrics used in the construction of boat projects are synthetic fibers, designed for strength, durability, colourfastness and resistance to various environmental influences.
The most common materials in use are Acrylics (such as Sunbrella®), Vinyls (and vinyl meshes), Nylon (cloth and webbings), and Dacron™, which is actually a brand name for a polyester material commonly used for sails. All have different strengths and weaknesses, and are suited for different applications as described in this section. Included in this section are some hints on care and cleaning. For further details you should go to the Internet or to the manufacturer for information on general cleaning and stain removal. Sometimes the recommendations change.
Overall, however, you can’t go far wrong by rinsing off canvas or vinyl as often as you can with fresh water – synthetic fabrics grow mould on the dirt, not on the fabric. So, keeping it dust-and-salt free goes a long way to making it last longer. Also as a general principle, when cleaning, don’t rub the heck out of the fabric with brushes or abrasive cleaners – be gentle!
Acrylics
Acrylic is by far the most common fabric used for exterior canvas work. Sunbrella is one of the popular brand names of acrylic. It is available just about everywhere in the world in a wide variety of colour choices and is easy to sew.
Material – Solution-dyed acrylic. This means that the dye is incorporated into the fiber, not added on later.
Properties – Provides up to 98% shade factor depending on how dark the colour is. It is water-resistant NOT waterproof.
Strengths – Colourfast, resistant to mildew if it is kept clean, resistant to UV, environmental
chemicals and weather. It does not shrink or stretch under normal conditions but it can shrink if it is washed/dried at high temperatures. Use lukewarm water and never machine dry it. Acrylic ‘breathes’ which means that condensation does not build up under a cover or inside a bag made of acrylic. Weaknesses – Acrylics have poor resistance to chafe so be sure to place chafe protection patches at the critical areas.
Life Expectancy – can be made to last 10 years with proper care.
Width – available in 46” and 60”
Use for – dodgers, awnings, biminis, dinghy covers, sail covers, sail sacrificial strips, cushions, bags, equipment covers. Just about anything!
Cleaning Information – Mould grows on the dirt, not on the fabric, so rinse it regularly (monthly) with fresh water to keep it clean. Remember, the more you scrub, the more you remove the waterproofing. After a vigorous cleaning, re-waterproof the fabric.
Sewing Tips – It is possible to sew acrylic canvas with a decent home sewing machine and many have done it. Exterior projects won’t last as long, of course, due to the smaller size of thread and will have to be restitched more often. If your
6
home or industrial sewing machine can handle Tenara™ or Profilen™ brand thread then you will not have to restitch. Ever!
Use staples or seamstick to hold the seam together before stitching (See Section 2 - Seams). Pins are hard to use on heavy fabric and tend to distort it. Regular seamstick does not stick very well to Sunbrella, so press very hard and roll down hard to make the seamstick stick. Or use the seamstick designed especially for acrylics.
The selvedges (edges) are not true woven-in selvedges. They are hot-knifed at the factory. Therefore, they will fray eventually. Keep this in mind if you think you can use the selvedge as a hem edge.
The fabric is not forgiving of mistakes. The stitching holes will show if you rip out a seam. Be careful of the edges after you have hot-knifed them – they can cut you.
Lined Acrylics
Sunbrella Plus® is Sunbrella with a urethane coating on one side. It is more water resistant than regular Sunbrella, but it is still not totally
permanently waterproof. It does not ‘breathe’ as well as plain Sunbrella and is not available in all colours.
It is heavier than plain Sunbrella, and is best used for dodgers & biminis where you need a little more water-resistance.
Cleaning information – don’t try removing mould with chlorine bleach or you will damage the urethane coating.
Sewing tips- arrange it so that the coated side is on the underside of the dodger/bimini.
Sea Mark™ is Acrylic with a marine-grade vinyl lining. This fabric has all the benefits of Sunbrella (except breathability), but because it is bonded to vinyl, it is totally waterproof. Use it for dodgers & biminis
Sewing tips- Position the vinyl coated side as the underside of the bimini/dodger.
Vinyls
Vinyls are typically easy to clean and are resistant to environmental insults. The heavier weight vinyls are extremely useful for making patches for areas of your project that are subject to chafe. Most vinyl fabrics are made of nylon or polyester yarns, coated on one or both sides with vinyl. Nylon is stronger than polyester, and the heavier the weight of the fabric the stronger and more chafe-resistant it is. Vinyl Coated Nylon
Examples are the brand names Shelterite® or Coverlight®.
Properties – Strong and flexible, waterproof Strengths – Resists tears and abrasion.
Weaknesses – If this actually is a weakness, a large cover made of Shelterite is tremendously heavy. Also, vinyls do not ‘breathe’, so condensation can build up inside a cover or bag.
Life Expectancy – 8 years or more Width – 61 ¼”
Use for – chafe and strength patches (e.g. reinforcing for grommets, bag handles, awning patches). It can also be used for canopies, industrial covers and tarps, keeping in mind the weight factor. Cleaning Information – do not use abrasives or solvents.
Sewing Tips – Look closely - one side of the fabric is smoother because it has the thicker layer of vinyl. This is the right side.
All vinyls are very unforgiving of sewing mistakes. When you rip out the stitches, the holes will show. Instead of stitching, vinyl fabric can be glued together with HH-66 Vinyl Cement.
Vinyl-coated Polyesters
Fabrics in this category include Weblon®,
Stamoid®, Top Gun™, Odyssey™ and Aqualon®. Polyester is not very resistant to UV, but it is very
7 strong and does not stretch very much. Therefore it
is used as a core fiber and coated with vinyl. Properties – Strong and light. It folds up small, is low-stretch and waterproof.
Strengths – Easy to clean, resists dirt, colourfast. Excellent resistance to UV, mildew, and bird crap. Weaknesses – won’t tolerate chafe or flogging in the wind. Protect ‘chafe’ areas with patches, and
reinforce areas subject to strain. Don’t place the fabric on a rough surface like a concrete dock and walk on it – you will hurt the finish.
Life Expectancy – with proper care, it can last 10 years.
Use for – Awnings, Dodgers, Biminis, Equipment Covers, Storage covers, Sunshades.
Cleaning Information – Don’t fold up and put away wet – although it is mildew resistant, eventually mildew will grow on the dirt. Do not use abrasive cleaners, solvents or gasoline – you will ruin the finish. Use dish soap and water, and rinse well. Sewing Tips – When turning up a hem, always seamstick the hem first – don’t try to freehand it, it’s too slippery.
Other Vinyls Upholstery Vinyls
These fabrics have soft vinyl coatings on backing fabrics and are most often used for powerboat seats, cockpit cushions and other exterior seating such as center console dinghy seats
Brand names include Naugahyde® and Nautolex®. Material – Knit-back vinyl or fuzzy-back vinyl. Properties – The knit-back reduces stretching. Strengths – easy to clean, waterproof, resistant to UV.
Weaknesses – Nautolex can crack if folded or in cold weather, Naugahyde is resistant to cold.
Neither breathe, so are susceptible to mildew on the inside.
Life Expectancy – up to 8 years if kept clean. The sun will bake in dirt and cause the fabric to go hard and crack.
Width – Both are 54” wide.
Use for – Interior & exterior upholstery, fuzzy-back is great for table covers.
Cleaning Information – Abrasives will very quickly ruin the protective finish and it won’t be waterproof any more. Rinse often and use mild dish soap and never scouring powders.
Sewing Information – Like all vinyls, upholstery vinyls are very unforgiving of mistakes. Holes will show if you rip out seams. Don’t sew over and over the same holes – it will weaken the fabric.
Quilted Vinyl is a fabric with a vinyl front, soft padding and a thin vinyl backing, all pressed together into ‘corrugates’ (Fig 1-1). It has all the same properties as Nautolex.
Sewing Tips – The quilting tends to pull the fabric in. Really stretch it out when stapling, sewing, measuring and cutting.
8
Vinyl Meshes
Brand names include Phifertex®, Textilene®, Awntex®, Phifertex Plus®.
Material – Vinyl-coated polyester yarn Properties – 70% to 90% shade protection
Strengths - stays flexible at all temperatures, flame retardant, resists UV and mildew. Gives shade without trapping heat or stopping air flow. The tighter weaves are more dimensionally stable, and provide more sun protection.
Width – 54” 12-15 oz/sq yd
Use for – Cushion bottoms, sheet bags, shade curtains. My personal opinion is that the open-weave mesh is really too rough to be comfortable to sit on – sort of like sitting on a screen door. If you want a vinyl mesh for the cockpit cushions, try a tighter weave like Awntex or Phifertex Plus. Sewing Tips – Mesh fabrics – There is no right or
wrong sides to these mesh fabrics.
Don’t use seamstick on any mesh fabric –
eventually it bleeds right through and makes a dirty sticky mess.
Cushion Underlining
This is a polyester mesh with a matte vinyl coating. It is light, inexpensive, easily cleaned and durable and does not stretch very much.
It can save you money on an upholstery project because you can make the cushion bottoms of this material and not have to use a possibly more expensive upholstery fabric for the bottoms. It is not really rugged enough for outdoor use, however, and is best suited for interior upholstery.
It should last the life of the cushions. Width – 54” 6 oz/yd
Sewing Tips – because it does not stretch as much as a vinyl like Nautolex, it pulls the cushion in nicely.
The underlining bottom may be just barely visible in places such as at the front of the cushion. To hide the underlining, sew a 1” or 2” strip of the
upholstery fabric to the edge of the cushion bottom
before assembling the cushion as shown in Fig 1-2. (See also Section 6 – Cushions).
Don’t use seamstick – like all meshes, it will bleed through.
Clear Vinyls (Window Material)
Window materials are usually clear vinyls, although you can use thin polycarbonate, too. Polycarbonate is wonderfully clear and non-wavy, but it cannot be folded and unless specially treated, does not last long unprotected in the sun.
Clear vinyls can be bought by the sheet (called press-polished vinyls) or off a roll.
The most well-known sheet vinyl is Strataglass™. It is a polymer-coated press polished vinyl. The polymer coating seals and makes the vinyl more scratch-resistant, and keeps the vinyl supple. It resists atmospheric chemicals, blocks 70% of UVA and 100% of UVB. It has excellent clarity and longevity – with a life expectancy of 12+ years. But it is quite expensive compared to roll stock.
Width is 54” x 111” sheets, 40 mil or 30 mil thick. Strataglass is very particular in its care and cleaning. See instructions on their website. Don’t use paper towels, or any cleaning products unless
9 any window vinyl to come into contact with silicone
or sunscreen – it will turn the vinyl cloudy.
Window vinyl – is extruded clear PVC, and comes on rolls like many other canvas fabrics – so it is called “Roll Goods” sometimes. It comes 20 mil or 30 mil thick. 20 mil is not as clear as the 30 mil, but rolls up smaller. 30 mil is not as easily rolled, but lasts longer. Use 30 mil for most dodger windows – some applications where the dodger is rolled up small and zipped into a cover will be better with 20 mil.
It is very prone to scratching, so handle it carefully. To clean – hose off any salt crystals – don’t rub them off – the salt crystals will scratch the vinyl. Wash with mild soap and water, don’t use paper towels because they will put tiny scratches in the surface. Use a commercial vinyl window cleaner for best results and nothing containing ammonia. Sewing Tips – Because window vinyl is so prone to scratching, cut it out on a smooth, clean surface, or better yet, cover the surface with a piece of fabric like a bed sheet. Don’t drag the vinyl along the cutting or sewing surface, place it down carefully. Put a bed sheet or something under it and all around the sewing machine. (Careful you don’t sew the bed sheet to the vinyl!)
Window vinyl is very prone to picking up marks from permanent marker – such as the marks you make on plastic pattern material when patterning a dodger. If you are quick, you can remove
permanent marker with a commercial vinyl cleaner. Use only a grease pencil to mark window vinyl – never permanent marker.
Use a long stitch on the sewing machine to reduce the number of perforations which can weaken the material.
Patterning plastic – use clear polyethylene drop sheets – the kind used for painting houses. Get it at the hardware store. It is cleaner to use than
newspaper.
Mylar film – 7 mil thick is a good material to use for more permanent patterns, or for patterns that you need to make many copies of – such as corner patches for awnings. Mark it up with permanent marker. Be careful of the edges – they are very sharp. You can also use thin cardboard but the edges get fuzzy after a lot of use.
Sailcloth
Dacron® is actually a brand name but is almost synonymous with sailcloth.
Material - polyester
Properties – does not stretch much, does not absorb water
Strengths – very strong, resists many chemicals Weaknesses – rots in the sun, not chafe-resistant, does not ‘breathe’
Cleaning Information – hose off as frequently as possible with fresh water. Wash very gently with a mild detergent and rinse well.
Uses - reinforcing patches for strength. Not a good choice for an awning because it is not all that great for UV resistance, and it can be noisy in the wind. Sewing Tips – cut with a hot knife.
When patching sails, it is imperative that you match up the grain of the patch with that of the sail, and use the same weight of cloth.
Spinnaker Cloth
Material – rip stop nylon is nylon fabric with an added extra basket weave through it to give it extra strength and to stop it, well, ripping.
Properties – very light and strong, stretches. Strengths - Strong and resists chafe
Weaknesses – not resistant to UV, stretches when wet, shrinks in the sun
10
Cleaning Information - never use bleach on nylon Uses – sail bags, light awnings (these will be noisy in the wind), and bags.
Sewing Tips – reinforce corners and strain areas. This material is very slippery to sew – use seamstick or staples to control it.
Insignia – this is Dacron with an adhesive back. It comes in rolls of various widths – 2” through 8” or so, or by the yard in 54” width. If you want to have some on hand for sail repair, keep in mind that the 54” width is very hard to store neatly, the roll stuff is better. Insignia is very lightweight Dacron – like spinnaker material – so don’t expect it to repair a big structural rip all on its own.
Leather
Leather used in canvas work is usually split cowhide. It is stretchy, easily machine-sewn and shrinks a little when wet. It breaks down in the sun, however, and needs to be replaced periodically. Use it for chafe protection like the forward edges of dodgers but if you want better resistance to UV, use vinyl such as Shelterite for this instead.
Sewing Tips – Making seams in leather is not practical because it is usually too thick. Instead, just butt the 2 raw edges together and machine zigzag or hand stitch them together (see Fig 1-3). To hand stitch leather, sometimes it can be easier to ‘pre-punch’ holes in the leather using your sewing machine. Use the largest machine needle you have and use no thread in the sewing machine. This will also make your hand stitches nice and even. Making slits in leather – Mark the slit, punch tiny holes with a small punch at each end of the mark, then slit in between (Fig 1-4). This helps keeps the slit from tearing.
11 Foam
Closed Cell foam is dense, relatively hard and it shrinks. But it floats and does not absorb water. Use it for floatation gear and cushions if you can stand it. I have had good luck with gluing 1” regular interior foam on top of the closed cell to provide a layer of soft padding. Then cover with exterior-grade upholstery vinyl on top, and vinyl mesh fabric on the bottom. Made this way, the cushions can take an occasional light rain. But in a heavy rain situation you need to take them inside.
Open Cell foam is softer, feels ‘crunchy’ when you sit on it, and water drains right through. It is light, and it sinks fast if it flies overboard! To prevent this, secure the cushion to the boat with lanyards or other attachment.
To ensure the cushion does not ‘bottom out’ and to make it float, you can glue ½” closed cell foam to the underside. Punch holes in the closed cell foam before gluing it on to allow the foam to drain. Interior Foam comes in many densities and
thicknesses. The best foam is made from latex but if you can’t afford this, buy the best quality (usually this means the most expensive) foam that you can afford. Especially for foam that you will be sitting on or sleeping on regularly. If you buy poor quality foam, your hard work will be all to waste when the cushion bottoms out and loses its shape. See Section 6 – Cushions for much more information about working with foam.
Polyester Batting is used to wrap interior cushions so as to fill up the corners and give them a softer look. This is the same batting that is used in quilting and is available in most fabric shops. Use spray adhesive to stick it to the foam.
Notions
Basting Tape
Once you discover basting tape (seamstick is one of the brand names), you will wonder how you ever managed before! Seamstick is double-faced sticky tape that comes in rolls of various widths. The most common widths to keep on hand are the ¼” for zippers, the ¾” for joining large panels and ½” for everything else. 3M makes a more expensive seamstick that has no plastic carrier strip for the adhesive – it is just pure goo.
Seamstick does not stretch – in fact, it tends to pucker the fabric it lays on, so apply the seamstick loosely. The easiest way to do this is to stretch the fabric out slightly using scratch awls (which will be described later) before applying the seamstick. Stitching through the seamstick can help seams to be more waterproof. It can make the sewing machine needle sticky, however, especially as the needle gets hot from friction. Spritz the needle with silicone spray occasionally as you sew, or use rubbing alcohol to clean things up periodically. Seamstick adhesive can bleed out with time and heat. If you apply it too close to the raw edge of the fabric (especially on vinyl), it will show eventually and look dirty and awful, so apply it about 2mm in from the edges.
To store it, keep it wrapped up tightly in a zip lock bag. It will go all sticky if kept in a really hot place, and it will not stick very well in the cold. In the tropics, I keep mine in a zip lock bag, buried in the fridge on the boat, and bring it out to warm it up before using it.
When sewing vinyls, you can use a smaller size of seamstick (say, ¼” instead of the ½” for joining seams), because the seamstick sticks VERY well to vinyl. Keep this in mind – if you make a mistake, it
12
is really hard to get the seamstick adhesive off vinyl fabric.
Seamstick also sticks very well to leather, so is useful when adding the chafe strip along the front edges of biminis and dodgers.
You can use ¼” seamstick on hard surfaces like outboard covers or steel dodger frames to hold patterning plastic in place. Don’t leave it on too long though! And make sure when using seamstick in this way, that you use the kind that has a plastic carrier strip (you can tell by taking off the paper and stretching the tape – there is a tough plastic film). Cleaning information – seamstick glue is really hard to remove. Try Acetone or Mineral Spirits, (check that it doesn’t harm the fabric first!) which will soften the adhesive to a horrible goop, then scrape it off as best as you can. Also, if you can find it, “Goo Gone” works pretty well.
Webbing
Webbing comes in several materials, widths and colours.
Polypropylene webbing is the weakest – it is not UV resistant at all, so don’t use it for outdoor projects. It is inexpensive, and it floats. Use it for interior reinforcing, and bag handles.
Polyester webbing (Dacron) is the best for use in sunlight.
Nylon webbing shrinks with age but is good for outdoor projects. There are various weights – regular, heavyweight and tubular. Use the
heavyweight (commonly bright blue in colour) for jacklines, tethers and straps that people are going to hang on.
Spectra webbing does not stretch or absorb water, it is light and extremely strong (breaking strength around 7000 lbs), very resistant to chafe, (also very expensive) and resistant to UV.
Tubular webbing, made of polyester, shrinks less than nylon, so is preferred for awnings for its strength and ‘less stretch’ properties.
Binding
Centerfold binding – is actually flat, but is woven so that it folds easily down the center. The acrylic centerfold binding is 7/8” wide and is sold in a wide variety of colours. You can use it to encase raw edges – on covers, dodgers, biminis, bags – to protect the edges and add a decorative finish. Double fold binding – comes in ¾” or 1” wide, made of acrylic and is a tape with both edges already folded under. It is great for binding edges. (See Section 2 – Binding Edges)
Double fold binding is cut on the bias so that it curves around corners easily. You can make your own by cutting fabric in strips along its bias, fold the edges under and iron with a very cool iron. (If
13 using acrylic canvas, use a very cool or even a cold
iron). It’s a real fiddly job to do.
Vinyl Binding comes in single or double fold, a couple of different widths. It is strong and resists mildew, but don’t use cheap vinyl binding for exterior projects – it will crack over time and look terrible. Use Stamoid binding for exteriors.
Piping and welting
For making up your own piping, you can buy a special cord made of hard foam – this is nice because it does not mildew or rot, it is easy to work with and inexpensive to buy.
Premade vinyl piping is also available. If you are planning to use it for exterior projects, check the UV resistance of the material.
There are a couple of specialty pipings available – “Hidem” is a vinyl binding that is already folded along its edges. The folds can be plain or with a piped edge (Fig 1-5). It is useful in areas where the fabric joins a hard edge. Apply the piping trim by opening up the folds and stapling or tacking it down in between the folded edges.
Boltrope or ‘Keder’ is used in conjunction with awning track to make a secure attachment for cushions, dodgers and sunshades to the boat. (See Section 2 – Piping)
Zippers
There are several different sizes of zippers. The most common are - #5 (teeth are 3/16” wide when closed), and #10 (5/16” teeth). The #5 size is usually used for cushions, and the #10 for biminis and dodgers and other exterior canvas. Sometimes you will see #8 but because it is not as common, it is harder to find replacement heads.
Zipper teeth are usually separate little pieces of plastic, but also available is the ‘coil’ type. These are not as common or robust, but curve around corners easier.
Zippers are made as ‘continuous’ or ‘jacket’ types. Continuous means you buy the zipper tape by the yard, cut it to length and put on the heads as required. Use continuous zips for openings that don’t need to separate completely – like bags and cushions. Jacket zips open and separate, well, just like a jacket. They have a fitting at the bottom where the 2 sides hook together and are able to be separated entirely. Use these for things like biminis, dodgers and removable shade curtains.
Jacket zips come in standard lengths – 24” through 96” in one foot increments, and also 120” and 180” and others. If you need a different length than the standard length, just buy the next size longer, and cut and finish to the length required. (See Section 2 – Zippers)
Jacket zips are commonly the #10 size, but are also available in #5.
Zip heads are available with a single or double pull slider – double pull meaning they can be opened from one side or the other. Do not use zippers with metal heads if you are sailing in saltwater. Even for interior projects. The salt air corrodes them terribly. If you do have metal heads that are all stuck shut, soak them in vinegar to help work them free. And
14
then take them off and replace them with plastic heads.
Zippers die in the sun pretty quickly – about 2-3 years in the tropics. Black lasts longer than white. RiRi™ brand zippers, and zipper teeth made of Delrin™ plastic are UV resistant and are worth the extra cost for exterior projects. In any case, try to sew the zipper so that the teeth are protected from the sun by a flap of fabric.
.
Velcro
This is the brand name for the most common form of hook-and-loop fastenings. Velcro is one of those words that is used interchangeably for hook-and-loop, just As Sunbrella is used interchangeably for acrylic canvas.
Velcro is a very useful fastener, and here are a couple of things to know.
Nylon Velcro rots in the sun very quickly. Black lsts longer than white. It also shrinks a lot over the course of time. So, when stitching Velcro on, try to avoid stretching it. You can pin out the fabric and really stretch it out, so that when you seamstick on the Velcro, it fits more ‘loosely’ on to the fabric. If the Velcro is going to be anywhere near the sun, make sure you cover it with flaps, or you will be replacing it often.
Velcro is also available made from polyester instead of nylon. It lasts much longer in the sun, and does not shrink very much. I am not sure if studies have been done, but I feel that the polyester does not stick to itself as strongly as the nylon does. Velcro is also available with a sticky back – useful for outboard motor covers, as you will see in Section 4 – Covers.
15 Rope and cord
Small leech line is useful to have on hand for projects that need a thin cord (e.g. hatch covers) Solid braid polyester cord is commonly used for drawstrings and tie-downs. The table below describes the most common sizes available.
Size Diameter (“) Breaking Strength
3 3/32 200 lbs 4 1/8 310 5 5/32 425 6 3/16 620 8 ¼ 1050 10 5/16 1600 12 3/8 2175
For making your own boltropes and piping, nylon is not a good choice – it shrinks with age – use
polypro instead.
Shock Cord or Bungee Cord is the stretchy elastic used in canvas work. Common sizes are 1/8”, 3/16”, ¼” and 5/16” diameters, depending on the strength needed. It does not last very long in the sun so needs replacing periodically.
To cut shock cord, wrap a little piece of insignia sticky-back tape around the area to be cut. Heat up the hot knife and cut it fast (cuts it faster and stinks a lot less).
To join shock cord, align the two ends next to each other as shown in Fig 1-6. Place a shock cord clamp (also known as hog rings) around the join. Use special shock cord pliers (or ordinary pliers – it’s just not as easy) to squeeze the clamp shut. Put on another clamp over the join, with the opening facing in the opposite direction to the one you just squeezed shut. Use the pliers to squeeze this one shut.
To remove the clamps – once the shock cord clamps are squeezed on, they are practically impossible to remove. It is easiest to just cut the shock cord.
16
Hardware
Grommets
Grommets and the tools used for their installation are referred to either by size or by diameter. See the table below.
Spur Grommets – have little sharp points all around on one half of the grommet and are the best type for canvas work because they attach strongly to the fabric. These spurs lock onto the edge of the other half of the grommet. It can get expensive to have all the set tools and hole punches for all the various sizes, but the most common sizes used in canvas work are #0 and #1.
Eyelet Grommets – or plain rim washer grommets are used for light-duty areas that do not have a lot of stress such as for ventilation holes. They have their own set of die sets but use the same hole punches as the spur grommets.
Grommet Sizes:
To install grommets you need a rubber mat (or other surface like hardwood – not metal or it will dull the hole punch), a hammer, a hole punch cutting tool and a matching setting tool with pedestal as shown in Fig 1-8.
Place the rubber mat on a really solid surface. Use a flat faced (rawhide is best) hammer to bang a hole in the fabric with the hole cutting tool. If you have a hard time cutting the hole, move the rubber mat to a more solid, less springy surface like concrete or stone, not wood.
Now take the setting tool. Place the pedestal on a solid surface. Set the male part of the grommet onto the pedestal. Force the hole you just made in the fabric over the grommet’s shaft. Place the spur ring on top, spurs down, and wham it hard with a hammer – a heavy rounded hammer with a nylon head as shown in the diagram is a good tool to have f you are doing a lot of grommets. An eyelet
grommet doesn’t need nearly the same ‘wham’ as does a spur grommet.
It is important to know that a spur grommet must be installed in the proper thickness of fabric layers. If the layers of fabric are too thick, the little spurs will not be able to cut through the fabric and grab onto the other half of the grommet. If the fabric is too thin, the spurs will cut a hole into the fabric and it will rip right out. In that case, add a reinforcing layer of fabric to add thickness.
Size Size “ 0 1/4 1 5/16 2 3/8 3 7/16 4 ½ 5 5/8
18
To remove spur grommets, turn the grommet ‘upside down’ (the side with the spurs on top) so that you can see the little retaining ring formed by the male part of the grommet. At several points along the inside of this retaining ring, bang at the edge, towards the grommet hole, with the point of a flat screwdriver (Fig 1-9). Use a screwdriver that you don’t care much about. This breaks the ring’s seal and lets you separate the two sides.
To remove eyelet grommets (which are much weaker), just bend the edge up and pull it away from the fabric – use pliers if necessary (Fig 1-10).
Snaps
Snaps are good general purpose fasteners – stainless steel will corrode far less for outdoor applications than nickel plated brass. You can get regular snaps, or a special ‘one way’ snap that only opens when pulled in one direction. This is useful but not necessary for dodgers or something that you don’t want to come off accidentally. These one-way snaps use a special setting tool, different than the ordinary snap setting tool.
To remove snaps, use a pair of side cutters. Insert the jaws of the side cutters between the socket (or stud) and the fabric, and squeeze underneath to pop it off (Fig 1-12).
19 Lift the Dot™ Fasteners
Lift the dot fasteners are designed to open when lifted from one side only, making them quite secure against accidental opening. They are most often used to attach dodgers and enclosures to the side of the boat. No special setting tool is required to install them – just make slits with a jackknife (you can heat it up with a flame to seal fabrics like Sunbrella) and use pliers, a hammer and screwdriver or something to bend the little hooks around. The studs are available with a screw for use in attaching to hard surfaces.
Tenax™ & Menax™ Fasteners
These fasteners are not commonly seen in North America but are seen in Europe. They are quite expensive. The Tenax fasteners are metal, and the Menax are plastic. They consist of 4 pieces like a snap fastener – one pair of fittings for one side and one for the other. They operate like a lift-the-dot but are even more secure. No special tools are required to install them.
Twist-lock Fasteners
Also called turn buttons or Commonsense™ fasteners, these consist of an eyelet, through which a stud is pushed, and turned, to secure the
attachment. It is a good fastener to use if the connection will be subject to strain.
A special cutting tool is recommended for cutting the oval holes although I have used a grommet hole punch for this. Just punch twice to make an oval hole.
The stud portion of the assembly is available in three styles. A base with screws, prongs for use with a backing plate, or with 2 holes in the base. The studs with 2 holes in the base can be screwed onto a hard surface, or you can use the eyelet portion of a snap fastener to secure the stud to fabric, or you can rivet them onto a backing plate, or you can even sew them on.
Usually these fasteners are made of nickel-plated brass, but there is another brand called Permalock® made of UV resistant plastic – these are long-lasting and don’t corrode.
