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Canoeing 101


Wood Gunwale Replacement for Composite Hulls

Canoes with fine woodwork are a tradition at Mad River Canoe. The rails, seats, yokes, carry handles and thwarts on your Mad River Canoe are native Vermont straight-grained ash, chosen for its resiliency, strength and aesthetic appearance. Unlike aluminum or plastic materials, white ash will not kink upon impact and cause undue damage to the canoe hull. 

Mad River Canoe has used a variety of woods for decks over the years, ranging from mahogany to butternut to walnut to beech. Most of the changes have been made to respond to sustainability of wood species. Currently, our decks are made of beech, a native American hardwood with excellent stability and durability and just as importantly, a wood that is well-managed and replenished. 

Wood gunwale replacement might require more craftsmanship than working with synthetic materials but the process need not be intimidating. It is recommended that you fully review the instructions before beginning the project so that you have a sense of what to expect and can judge whether you are comfortable with all the steps involved and have the necessary tools, etc. 

Most of the more complex steps occur at the ends of the canoe, from fitting the inwales (inside gunwales) to the stem of the boat and the decks. There are two alternative processes described in the instructions. One for a complete re-rail including new decks and another detailing a splicing process that allows the use of original decks.



Rails can be ordered from an authorized Mad River dealer. Replacement ash rails are available for all Mad River Canoes. Due to their length, ash rails cannot be sent UPS. The best alternative s to coordinate an order for replacement gunwales with a boat delivery to your dealer. 

A full set of wood rails has four pieces: two inside (inwales) and two outside (outwales) strips. The rails are not pre-bent or pre-drilled, but are flexible enough to follow the shape of the canoe by just clamping them to the hull. 

It is possible to replace a single outwale or inwale or the gunwales along one side if desired. On composite canoes, the outwale has a “kerf” on the upper surface. The kerf is a small extension that will cover the top of the hull laminate. The inwale fits flush against the inside of the hull and its’ top is butted up against the edge of the kerf, concealing the hull. Inwales can be solid or slotted. Slotted rails have cutaways evenly spaced through the central third of the gunwale. They can be merely ornamental or can be used to tie in gear or be used to set the canoe up as a hunting blind. Slotted rails do cost more than solid rails. Specify what rail you need (kerfed outwale or standard or slotted inwale) and the overall length of your canoe. The gunwales will need to be longer than the length of your canoe as length is measured straight along the keel line while the gunwales take a more circuitous route from stem to stem. To re-rail a 14' or shorter canoe you will need 15' gunwales, 15' or 16' canoes will require 17' gunwales, etc. 

For best results, however, it is recommended that you replace gunwales as a complete set. A better job results if all the rails are of the same age and moisture content. Older rails, especially if they have not been properly oiled, will be brittle and can break more readily than new one soaked in a penetrating finish such as Gunwale Guard. 

In most cases you can use existing hardware but to ensure that possibility be careful in removing gunwale screws and the bolts holding seats, yoke, thwarts, etc. The hardware is durable stainless steel but the heads or threads can be stripped during removal. 

It is an option to use non-kerfed gunwales intended for Royalex hulls on a composite hull if your dealer has such gunwales in stock. Care must be taken to sand down the exposed top edge of the hull laminate between the gunwales as this can be sharp and a bit ragged. The instructions that follow are written for the installation of kerfed gunwales but most of the steps are consistent for either gunwale style. 


On older model Kevlar/Airex models with foam core, the rails were glued to the hull as well as screwed and this can make complete removal more challenging. Use caution in breaking the glue joint as damage to the hull laminate can result. 

The other unique aspect of the Kevlar/Airex editions is that the inwales were kerfed. If you have a foam cored Mad River Canoe and are unsure of its’ construction, contact Mad River customer service with your serial number and we’ll help identify your canoe’s construction. 

Prior to ordering gunwales, back out the screws securing the decks to the gunwales to confirm that the decks are not glued in place. If they are glued, you will need to order replacement decks as well as new gunwales. Mad River Canoe stocks decks for current canoe models and those that have been discontinued for 3 years or less. Older model decks may no longer be available and you should factor this into your plans. If you have an older model canoe and the decks are glued to the gunwales, you may want to consider the “short-splicing” process that allows you to utilize those existing decks. This process is described at the end of the following instructions. 

Prior to 1985, Mad River used square sided gunwales on all canoes. In 1985, a new lighter rounded profile was introduced and all replacement gunwales are rounded. If your canoe has the square gunwales, you will need to plan to replace the decks as well as the gunwales. 

In the late 1990’s Mad River switched from ¼” hardware to 3/16”. This change was made to lighten the canoes and to enable improvements such as double bolting the yokes to prevent rotation. The easiest way to tell the size of your hardware is to look at the bolt heads. The ¼” hardware had round carriage bolt heads whereas the 3/16” has a Phillips head. 

Older hardware can be recycled during a re-rail. It is recommended that extra care be taken in drilling the larger holes needed to accommodate the ¼” hardware and that you drill a smaller pilot hole first. 

The size change has more impact if you find out that your existing ¼” hardware cannot be re-used and has to be replaced. The only hardware available is 3/16”. You may prefer to make a complete changeover even if some of the original hardware is usable. 


Replacement gunwales will need to be treated with Gunwale Guard or equivalent penetrating oil before installation. This is the perfect opportunity to ensure longevity with your new gunwales and the only opportunity you will have to thoroughly treat the surface of the gunwale that will be against the hull once installed. Mad River Canoe does not recommend the use of varnish to protect gunwales. Varnish is a brittle top coat protection that will be broken down as the gunwale flexs under normal use. It is not an effective protection for gunwales. 

Gunwale Guard is available in a natural or dark-stained finish. If your canoe has walnut or dark stained gunwales and seats you will want to use the dark finish. 


  • Gunwale Guard of appropriate finish 
  • Disposable or foam 1” brush 
  • Dry rags 


  1. Support gunwales at waist height. Dip brush into Gunwale Guard and apply to gunwales from end to end. 
  2. Rotate gunwales to allow access to other sides and repeat process. 
  3. Make sure to coat the ends of the gunwales and if during installation you trim the ends, to coat the newly exposed surfaces. 
  4. Allow 5 to 10 minutes for oil to be absorbed into wood. 
  5. Wipe down gunwales with dry rag to remove excess oil. 

In most cases, the original rail screws are reusable as they are stainless steel and resistant to corrosion. It is recommended that to minimize the chances of stripping the screw heads, first back them out manually with a screwdriver and then remove with reversible drill with a #2 Phillips head bit. On the average, 80 screws are required to refasten a 16' canoe. It is recommended to have a package (12) of screws available should you inadvertently strip a few. Composite hulls require 1 1/4" #8 screws to secure gunwales to hull and 2” #8 screws to secure deck to gunwales. If your canoe has a few years on it, it’s wise to acquire a dozen or two of replacement screws in case of need. 


  • Number of gunwales needed (1-4) of proper style for job required: (2 inwales (slotted or standard) and 2 kerfed outwales required for complete re-rail). Inwales are non-kerfed; outwales should have kerf. 
  • 80 pack of #8 x 1 ¼” stainless steel screws (if existing hardware cannot be used) 
  • Replacement decks (if proved needed) 
  • 12 #10 x 2” deck screws 

All above materials are available via your local authorized Mad River Canoe Dealer. 


  • Variable speed reversible drill            
  • 11/64” tapered drill bit 
  • 1/8”, ¼”. 3/16” straight drill bits        
  • #8 Countersink drill bit 
  • #P2 Philips Screwdriver bit            
  • #2 Phillips Screwdriver 
  • (2 or 3 spring or bar clamps            
  • 6 - 12 "C" or Welder's clamps* 
  • 20' Tape Measure               
  •  3/8" & 7/16" Wrenches 
  • Non-permanent Marker                
  • Sandpaper: 100, 120, 180 & 220 Grit 
  • Saw                        
  • Flat file 
  • Waterproof Wood Glue**            
  • Pencil 
  • Mild Cleanser                    
  • Rubber mallet 
  • 4 Home-made “S” Hooks*** 

*C-clamps with round clamp surfaces can tend to walk off the gunwale as you tighten the clamps. Take some scrap cardboard and cut into 2” squares and put squares of cardboard between clamp and gunwale to provide better grip and reduce tendency to walk. 

**Waterproof wood glue is needed if you pursue the “short splicing repair process that preserves original wood decks by trimming new gunwales short of decks. 

** “S” hooks can be made easily from a wire clothes hanger. Cut off about 12” of wire and bend into an S shape with each bottom curve of S large enough to fit around the gunwale to be used as an outwale. Bend the opposite curve at a slight angle to the bottom. You will use the S hooks to hold the ends of the gunwales close to the hull as you begin to clamp them at the middle. Hang the top curve over the side of the hull and put the outwale in the bottom curve. 


Prior to removing original gunwales, the locations of the seats, yoke, thwart, etc. need to be marked on the hull before removal. The new gunwales also need to treated with a fresh coat of oil. Existing gunwales are next removed from hull with care being taken to protect original hardware upon removal. Original Decks will lift off of hull with the old gunwales. Depending on model of canoe and date of manufacture, decks may be glued to gunwales or released when screws are removed. 

New gunwales are then clamped to the hull and tamped down to ensure they are properly seated. New screw locations are marked on the gunwale and countersunk holes drilled at marks. Screws are driven through hull and both inside and outside gunwales to secure gunwales starting from center of canoe and working towards one end and then the other. 

Once the gunwales are in place on the hull the new or original decks are fitted into place and secured with 2” screws. Seats, yoke, thwart or carry handles are then reinstalled at original locatons and finally a coat of oil is applied for maximum protection. 


  1. Mark location of all thwarts/yokes, seats, carry handles on hull of canoe with non-permanent marker. Trace outside of seat hangers to provide accurate reinstallation. All these fittings are hung from existing rails; removal of those rails will result in loss of position of original fittings. Also, trace the bottom edge of the gunwales on the hull from end to end and mark each screw location. 
  2. Remove all thwarts/yokes, seats, etc. from canoe. Canoe will become flexible once seats and thwarts or yokes are removed. This is not a problem. If you are concerned with maintaining shape especially if gunwale replacement may take extended period of time, make a brace from a 2 x 4 notched at same width as canoe's original beam. Label and mark ends of seats, yokes, etc. right or left to ensure proper reinstallation. Attach all hardware to each component to prevent loss. 
  3. Run tape measure around hull under existing rail. Mark center point of hull on each side of hull. These marks will serve as centering points for new rails. 
  4. Measure each new gunwale and mark center point on each piece. Note which are outwales and which are inwales and mark accordingly with pencil on gunwale (marker will bleed into wood causing discoloration). Lay new gunwales on top of old and determine which fits best on each side of canoe and label them as such. 
  5. For complete re-rail with new decks: 
  6. Starting from one end loosen and remove screws along one side of canoe. Leave other rail intact. You will be doing one side at a time. To ensure that hardware is re-usable, it is best to start with a #2 manual Phillips screwdriver (for 3/16” hardware and rail screws) and start screws loose before using variable speed drill. For short-splicing installation salvaging existing decks: 
    • Make sure that center mark on each inwale is aligned with center mark on hull. Clamp new inwales to old inwales to make sure they stay in place.
    • Mark and trim the new inwale 3” short of end of deck at each end.
    • Unclamp new inwale and move new inwale below existing inwale and clamp together.
    • Remove the screws located approximately 12" from end of decks. Draw a line bisecting a screw location at a 30-degree angle across the old rail. Angle should run so that end against hull will be closest to deck.
    • Making sure rails are firmly clamped to each other, pull both rails far enough away from hull to allow both to be cut with a saw. Cut both rails on line marked. Repeat procedure for opposite end.
    • Unclamp new rail and set aside. Be ready to clamp the deck and connected ends of gunwales in place on hull when the outwale is removed as per following instructions.
  7. Remove all screws securing gunwales to canoe. The screws that connect the decks to the gunwales are 2” or 2 ½” long and should be removed slowly if you are doing a complete rerail. If you are short-splicing the repair, leave these intact and clamp the remaining deck/gunwale ends assembly to the hull. 
  8. Clean the top of hull with mild cleanser, taking care not to wash off the traced line indicating bottom of gunwale. 
  9. Align new gunwales on hull, matching center line marked on hull with center line marked on each gunwale piece. Hook an “S” hook over hull at each end and put the ends of the outwale in the bottom curve. (If you are performing complete gunwale replacement: Let the uncut inwale ride up and over the ends of the canoe.) (If you are short-splicing the installation, let the cut ends of the inwales float inside the canoe.) 
  10. Starting at center clamp in place. Work towards one end aligning gunwales with top of hull and with each 
  11. other. Tamp down lightly on top of gunwales to seat them firmly on top edge of hull. Clamp as needed to maintain position. 
  12. Check to see that new gunwales are on line with line traced on hull at bottom of original gunwales. It is critical that the gunwales be fully seated on the hull, especially in the area where the sides of the hull begin to transition to the rise at the ends.   
  13. With pencil mark screw locations on inwale at center. Reference the old screw locations marked on the hull and position new screws to “split” the difference in old locations. It is preferable to drill new holes than try to re-use old holes. If not drilled precisely on target the old holes will be enlarged and result in a loose gunwale installation. Define center between older holes and mark gunwale. Move towards each end spacing marks 6” apart along the length of the rail. 
  14. Using the 11/64” tapered bit and countersink, drill holes for screws at marks at center and at next three marks in each direction. Set the countersink on drill bit by holding 1 ¼” screw against bit and aligning the countersink with the flare at the head of screw. Drill from inside of canoe towards outside, making sure that drill does not go all the way through outside of gunwale. 
  15. Insert screws into holes and tighten. Once these are secured you can release clamps at center.14. If you are short-splicing with original decks: 
    • With center of inwale secured, check to see that one end of the inwale fits snugly against the existing inwale attached to deck. If fit is good, cover ends of new inwale and ends of existing end pieces with glue. Slide a piece of wax paper between inwale and hull and then fit the ends together and clamp. If slightly too long, file down ends to achieve fit and glue. If there is a slight gap, mix some sawdust from sanding the rails into the glue and proceed to glue as described.
    • Check to make sure the rails are seated down to marked line and proceed to drill holes at new marks and then insert and tighten screws to secure gunwales. Withdraw the wax paper before tightening screws at ends. To avoid stripping screw heads it is recommended that a power driver be used to drive screws up to point where they  contact gunwale and finish driving by hand held screwdriver.
    • Repeat process at other end of canoe. Return to original end and wipe up any glue that may have run down from gunwale. Check other end as well.
    • Once glue has set on each joint, drill hole bisecting angle cut and secure with screw.
  16. If you are performing a complete re-rail with new decks: 
    • The inwale will need to be trimmed to fit inside end of canoe. Holding the rail in place over stem of canoe, trace contour of stem of canoe onto rail so that rail will conform to hull shape.
    • Make straight line at end of rail by sighting down to opposite end of canoe along keel line. Set saw just inside lines and trim off rail to form rounded end with straight side at center of canoe stem. If re-rail job will include complete replacement of inset decks, care must be taken to ensure proper fitting of the ends of the inwales. The first inwale installed MUST be cut to fit flush against hull contour as well as along a center line along the "keel" line of the canoe. The second inwale must be cut to fit against this centerline and hull contour. It is best to cut conservatively and hand shape with file or sandpaper to achieve best results. Coat all cut surfaces with Gunwale Guard. Set rail in place in hull and clamp to make sure both inwales are level.
    • Check to make sure gunwale is seated on the marked line and proceed to drill holes at new marks, working from center towards ends of canoe. Remove the “S” hooks. Even though the outwales are not trimmed at this point, they can be positioned properly to allow installation of screws to secure gunwales. Repeat for opposite end of canoe.
    • Tighten screws to secure gunwales. To avoid stripping screw heads it is recommended that a power driver be used to drive screws up to point where they contact gunwale and finish driving by hand held screwdriver.
  17. Repeat steps above to install opposite rail. 
  18. Drill a ¼” hole through junction at ends of inwale to provide drainage for any trapped water when canoe is inverted. 
  19. Treat underside of decks with Gunwale Guard and allow to dry before commencing installation. Decks will be installed with the more pronounced point at end below the gunwales, not above. 
  20. Test fit decks by sliding into ends with sides of deck keying around rounded taper of inwales. Ideally, decks will fit snugly against junction of inwales at stem of canoe. If getting the deck all the way up into position in end requires hull to be spread slightly that does not create a problem. 
  21. If satisfied with fit, tape the deck in place with duct tap running from wide end of deck down center of deck and over stem. 
  22. Align the outside rails along the outside edge of the hull. Mark point on rail where deck ends. Measure distance from stem to end of deck and mark 4 evenly spaced screw locations on each side. At narrow end, it is necessary to offset the first two screws so that they do not conflict with one another. 
  23. Using 11/64" tapered bit and countersink, drill holes for deck screws at marks. Insert 1 ¼” screws in first two locations and secure. Remove countersink and drill other holes deeper and insert 2” screws in other locations and tighten. It is not necessary to glue the decks to the inwales. The screws provide adequate purchase to secure the decks in place. 
  24. Drill ¼” hole vertically through the point of the deck to provide a drain for water trapped when canoe is inverted for storage or transport. 
  25. Trim off the ends of the outwales, leaving about ¼” extension beyond end of hull. Cut outwales at a slight angle with point of junction of outwales forming the point of the “V”. 
  26. Locate the marks defining seat locations, yoke/thwart, carry handles, etc. and transfer from hull to top of gunwales with pencil. 
  27. Using appropriate bit for the hardware being used (1/4” hardware needs 5/16” bit; 3/16” hardware needs ¼” bit). Carefully drill vertical holes through gunwales. Brush a coat of Gunwale Guard on the shank of the hardware before inserting hardware into hole. This will help seal the exposed wood inside the gunwale. 
  28. If using ¼” hardware insert bolts through rail and reinstall components. Tighten lock washers and nuts until contacting bottom of component. Lightly tamp top of bolt to set bolt throat in wood and tighten fully. 
  29. If using 3/16” hardware, slide cupped finish washer onto bolt and bolt into hole. Below component, place flat washer and lock nut and start nut. Draw nut tight. 
  30. Lightly sand top and sides of gunwales with progression of sandpaper grits. Collect a handful of sawdust and set aside. Apply fresh coat of oil to top and sides of new gunwales. Let sit for 5 to 10 minutes and wipe off excess. 
  31. Flip canoe over onto gunwales and mix up some glue with the saved sawdust and use mixture to fill the “V” shaped void at each end of canoe where outwales meet. This will strengthen that point and keep it from splitting if canoe is dropped on its’ end. Let dry. 

Apply coat of Gunwale Guard to bottom of gunwale, let sit, and wipe off excess as done prior.If additional information is required, contact your Authorized Mad River Canoe Dealer or call Mad River Customer Service 
@ 888/525-2925.