Fiberglass canoe new vinyl gunnels

[twmattox]

Hope to wrap up paint this week and put on the gunnels this weekend. I just don’t recall the screw spacing for the gunnels. I called Old Town and the lady there said “oh, about every 3-inches”. I have read anywhere from 4-6 inches.

Looking for some advice.

 

[dougd]

I just went to check my OT Disco 158 with vinyl gunwales. They are spaced at 4" but they are pop riveted in and not screwed. When we put aluminum gunwales on my friends Bell Mystic years ago we did it every 4" as well. On wood gunwales I use screws every 6". Are you using screws or pop rivets on the vinyl? I would suggest going with rivets.

dougd

 

[twmattox]

I was planning on nuts/bolts with lock washers. My concern with pop rivets was that the gunnel channel is a bit over ¼ inch wide. But, the canoe sidewalk is closer to 1/8 inch wide. I thought that the nuts/bolts could pinch it together whereas the rivets wouldn’t.

Why would you recommend rivets?

 

[dougd]

I had troubles finding rivets that I needed for a recent rebuild, took a look seeking out to find the right length which is where your measurements are at. I like rivets for a clean end on both sides, not bolt heads sticking out. It doesn't always pan out that way so whatever method works is the way to go. I've used bolts before but only at the bow end and I also prefer wood gunwales so that is nothing more than screws spaced evenly

dougd

 

[latremorej]

I was planning on nuts/bolts with lock washers. My concern with pop rivets was that the gunnel channel is a bit over ¼ inch wide. But, the canoe sidewalk is closer to 1/8 inch wide. I thought that the nuts/bolts could pinch it together whereas the rivets wouldn’t.

Why would you recommend rivets?

I taking a stab in the dark here but I always assumed that cost and weight were the reasons you see aluminum rivets on those gunnels. SS bolts, locks, and cap nuts would get pretty expensive no? Every 3" for roughly 17' of gunnell..(16' canoe right?). about 140 bolts? How many bolts are in a 10lb box?

Maybe you could squeeze the gunnell in a clamp to close the gap, then rivet?

I have little experience on this.... just my thoughts

Jason

 

[recped]

SS bolts, locks, and cap nuts would get pretty expensive no?

Jason

Yeah, I got "sticker shock" once when I had to remove the end caps of a boat to enable nesting. It needed to be reattached in the field so rivets were not a viable option, 6 SS bolts and nuts for each end...ouch! Of course when you are spending a few thousand on a float plane a few bucks for bolts isn't a big deal but still..........

 

[Guest]

I was planning on nuts/bolts with lock washers. My concern with pop rivets was that the gunnel channel is a bit over ¼ inch wide. But, the canoe sidewalk is closer to 1/8 inch wide. I thought that the nuts/bolts could pinch it together whereas the rivets wouldn’t.

Why would you recommend rivets?

I am confused about how you would install vinyl gunwales with bolts and nuts. The usual vinyl gunwale has a box channel inwale that would be inaccessible to install the nut, unless you used a 2” long bolt or machine screw and went all the way through the inwale. Perhaps the vinyl gunwales you have are different.

FWIW, here is a section of vinyl gunwale in profile. Disregard the section of aluminum gunwale; I use that piece of RX hull with vinyl and aluminum gunwales with webbing loop and snap rivet for shop demonstration purposes:

P3150654 by Mike McCrea, on Flickr

Why rivets? They are less expensive, lighter, easier to install and less obtrusive.

I have an unadorned piece of scrap vinyl gunwale here, probably from Old Town or Mad River. The channel that the hull material fits into is skinny, although in this case over ¼” wide. The inwale is a rectangular “box”, fully 1 wide x 3/4” tall, plenty of room for a pop rivet shank to fit before it is compressed, squeezing the skinny outwale channel closed tightly against the sheerline.

Yes, the pop rivet will squeeze the gap differential closed, provided you install the pop rivets properly, pressing the rivet tightly against the outwale while you squeeze the rivet gun.

3/16” diameter x ½” long pop rivets should work. The pop rivets on our canoes with vinyl gunwales are, on every canoe, spaced about 6” apart. On a 16 foot hull you will need around 70 pop rivets, so buy two 50 count packages.

Your hand will hurt after compressing/installing 70 pop rivets.

 

[twmattox]

My initial plan was to drill a small hole on the inwhale so I could put an acorn nut on the bolt. Then planning on using those holes for shock cord etc. But, you guys are correct on the difference in cost of rivets vs bolts. Plus, the whole not having to worry about them loosening up. I was more worried about the pop rivet pulling through the vinyl gunnel. From my experience, softer materials like vinyl needed washers on the back side. Is that not the case??

 

[Guest]

I was more worried about the pop rivet pulling through the vinyl gunnel. From my experience, softer materials like vinyl needed washers on the back side. Is that not the case??

On most (but not all) vinyl gunwales there is an aluminum L inside the inwale box (typo correction, not "bow) channel. Actually an upside down L; the “foot” of that L runs along the top inside edge of the inwale and provides support for the flange washer and machine screws that hold the seats and thwarts.

The vertical portion on that L is along the hull side of that inwale box channel and the pop rivet goes through and seats against that metal strip.

That said not every vinyl gunwale has an aluminum L. I regunwaled an old Explorer with no-insert vinyl gunwales from a defunct canoe manufacturer and those pop riveted gunwales have held fine for 10+ years, although I shortened the distance between pop rivets to more like 5” just to be sure.

Mostly fine, the flange washers for the seat hardware have indented the top of the vinyl gunwale a wee bit, and I could have prevented that by using larger flange washers. That canoe also has extra thwarts, stoutly truss hung seats and wood carry handles in addition to the carry handles on the plastic deck plate; that extra cross-structure probably helped with the rigidity of non-insert vinyl gunwales along the sheerline.

Some heavy duty canoes have a full square of aluminum in that inwale channel. I was surprised to stick my finger up into the open end of the (factory installed) vinyl gunwales on the 20’ Miramichi and find a full box aluminum insert. That extra gunwale structure probably helps a lot with a hull that size.

Presuming you already have the vinyl gunwales check for an aluminum insert.

FWIW, if the gunwales are too long for the canoe and need to be cut to length. Not really an “if”, that has been the case with every vinyl gunwale I have ever installed) you will have a couple pieces of scrap gunwale perfect to experiment with, ie what length pop rivet works best, how does the seated pop rivet look inside the inwale channel, etc.

If you have vinyl deck plates that match the vinyl gunwales those plates have a groove to accommodate the shape of the gunwale profile, but that groove usually ends several inches short of the tip of the deck plate, so you’ll need to cut off the excess vinyl gunwale plus those extra couple inches at each end.

You should have some scrap vinyl gunwale. Stick a thin piece of plywood in the hull channel slot on the scrap, drill some holes and install some test rivets for a lookee see (and hole drilling practice).

 

[twmattox]

Well, that is excellent to know; considering my gunnels are new from Old Town, I would assume they have the aluminum insert you are talking about. That said, my vinyl decks are all cracked and I threw them out. I thought it would be an easy thing to just buy new ones. However, I don't know who made this canoe...and apparently finding an easy replacement deck isn't so easy. Anyone have any thoughts on what I could do to "pretty" up where the vinyl gunnels end???

 

[stripperguy]

You can buy ABS sheet stock from McMaster-Carr in various thicknesses. That stuff is easily heat formed with a cheap heat gun from Harbor Freight.
Or, you can make up a quick and dirty mold and make your own fiberglass decks.
Or use a little foam and glass to make/shape your own decks.
All of these can be attached to your hull with hidden cleats and epoxy.

Personally, I would avoid wood (unless laminated inside glass and resin) since it's generally heavy and becomes a maintenance issue.

 

[Guest]

Well, that is excellent to know; considering my gunnels are new from Old Town, I would assume they have the aluminum insert you are talking about. That said, my vinyl decks are all cracked and I threw them out. I thought it would be an easy thing to just buy new ones. However, I don't know who made this canoe...and apparently finding an easy replacement deck isn't so easy. Anyone have any thoughts on what I could do to "pretty" up where the vinyl gunnels end???

All of the DIY deck plate ideas Stripperguy mentions above will work to varying degrees of attractiveness depending on your DIY skills. Another DIY possibility is to use Kydex (Google “Making a whatever using Kydex”). And I agree about staying away from wood deck plates with vinyl gunwales, for a variety of reasons.

You have Old Town Gunwales, so a set of Old Town deck plates will fit the profile of the gunwales with a perfect match. Of the other two factors are both angles, and only one is really critical.

That important one is the angle/dimensions of the V shape from tip to wide ends of the deck plate. I have a set of OT vinyl deck plates off some Old Town; they are 20.5 inches long at each gunwale channel side, and 12 inches wide outwale edge to outwale edge. That V angle really needs to match the dimensions of the gunwales in the stems. If that angle is too narrow the deck plates will not fit, although if the deck plate is a little too wide you can hit it with a heat gun and clamp induce a little arch in the otherwise flat deck plate to narrow the width at the wide end.

The other less important factor is the shape of the “vertical” tip of the deck plate where it covers the top inch of the canoe stem. More of those symbolic drawings you like.

On a canoe with recurved stems that “vertical” lip will be angled in towards the canoe /.

On a canoe with layout, where the stem of the boat projects outward, that “vertical” lip will angle outwards, away from the hull \.

On a canoe with near vertical stems that lip will be |.

That matching \ or / or | lip shape is minor, if the deck plate has correct V angle and wide end spacing to match the sheerline stems the not-quite-matching lip is inconsequential (still nicer if it form fit matches)

One more caveat with plastic deck plates for vinyl gunwales. I have a set of old Mohawk deck plates in the shop that are almost the same angle and dimensions as the Old Towns. They are from a whitewater canoe and the tip of the deck plates isn’t a sharp V shape, it is a wide, fat U shape to accommodate the blunt stems. And the scrap of Old Town vinyl gunwale I have will not slide into the ever so slightly different channels on those deck plates.

If you opt to buy new plastic deck plates from OT, with a form fitting gunwale profile, try to find a current OT canoe with similar dimensions, or a little wider for length, and induce a little heat gun & clamp arch if necessary to make them fit.

https://oldtowncanoe.johnsonoutdoors.com/canoes

I don’t know how responsive OT is on the customer service side; you might be able to mail them a pencil trace of the hull sheerline stem V shape, say 20” long on each side, and have them try to match it to some existing OT deck plate shape.

BTW, the last time I bought plastic deck plates they ran close to $30 a set. For a piece of molded plastic that must cost all of $2 to produce. Even the winky little 5” long deck caps are pricey, though less than a full sized deck plate. If you can find a winky short little deck cap that fits the OT gunwale profile just add wood carry handles (eh, I add them anyway, because I do not like picking up a canoe via the pop riveted deck plates.

Another caveat; that “$30 a set” was also years ago; they could be $30 apiece by now. But you have to weigh that against the materials cost to make something perhaps less than perfect.

Two more questions.

Out of curiosity, do your OT vinyl gunwales have aluminum inserts?

And, regarding plastic deck plate availability, where are you located? There are a few full service paddlesport shops that might carry the replacement deck plates you need; Blue Mountain Outfitters in PA carries plastic deck plates and end caps, Appomattox River Company, Austin Canoe & Kayak or one of the many outfitters near the Adirondacks or Boundary Waters might as well. Just bring a tracing of the hull at the stems.