Here is subject I've wanted information about for years.
I heard it called "deck canvas" some years ago by a gentleman who sold Chris-Craft boats back in the '50s. Deck canvas is the treated natural canvas that covers the forward deck and cabin top and sides of my boat.
I know from doing repairs and restoration of this original material that it is canvas and very similar to natural (undyed) heavy duck canvas that can be purchased at many fabric stores.
The old boat salesman told me that a nasty goo called "Airball" (or something like that) was slathered on the deck or cabin wood surface and the canvas was laid on top of this. An additional coat of Airball went onto the top of the canvas before it was given a thin coat of paint. He also told me that Airball was a dairy byproduct made by the Borden Company, it smelled to high heaven during application and attracted flies.
So what's the dope on this doped canvas covering? I'm lucky, the original stuff is still on my boat and I've had little need to do much in the way of repair.
Active 
UnansweredDeck canvas
Moderators: Don Ayers, Al Benton, Don Vogt
Deck canvas
1955 26' Chris-Craft Sedan Cruiser with Fly Bridge
Dan,
Look at the Post in "Finishing" called "Canvasing Cabin Tops". I just finished mine and, in fact, just today picked up the re-chromed pieces to put her back together.
Using the "Search" feature of "Boat Buzz" I found a few previous threads on the subject of "canvas" that I based my installation on. One process used sanding sealer to "size" the un-treated canvas/duck and another used borate, basically the stuff they make soap out of. I don't think any of these posts stated that their's was the method that CC used originally. What ever they used it sure held up great, didn't it?
I went with the disodium octoborate (a mouthful) to do mine. I hope it holds up for as many years as theirs has. I still have the original canvas at the helm (where the windshield was installed after the cabin deck was covered). The original canvas looks a lot thinner than my newly installed canvas does.
Next summer I plan to canvas the forward deck as well. Maybe I should research the original method a little more before I start on that.
Al
Look at the Post in "Finishing" called "Canvasing Cabin Tops". I just finished mine and, in fact, just today picked up the re-chromed pieces to put her back together.
Using the "Search" feature of "Boat Buzz" I found a few previous threads on the subject of "canvas" that I based my installation on. One process used sanding sealer to "size" the un-treated canvas/duck and another used borate, basically the stuff they make soap out of. I don't think any of these posts stated that their's was the method that CC used originally. What ever they used it sure held up great, didn't it?
I went with the disodium octoborate (a mouthful) to do mine. I hope it holds up for as many years as theirs has. I still have the original canvas at the helm (where the windshield was installed after the cabin deck was covered). The original canvas looks a lot thinner than my newly installed canvas does.
Next summer I plan to canvas the forward deck as well. Maybe I should research the original method a little more before I start on that.
Al
Thanks, Al! I just read the Cabin Canvas thread and that answers a lot of my questions.
About six years ago I used a different way of working with canvas in a very small area. I obtained an authentic Chris-Craft 19" deck hatch from eBay, spent about two months restoring this beautiful thing in the garage and used it replace a very ugly homebrew rectangular hatch someone put on the forward deck.
The framing and deck work needed to do this was the best work I've done on the boat so far. The deck pitch and crown was the complicating factor. It's a long story, but I'll cut through the woodwork and get to the chase: the hole left by the old hatch was a rectangular void much bigger than the round hatch I was going to install.
I left the old deck canvas on the forward deck intact. When the woodwork was done, I had two pieces of canvas to install around the base for the hatch hinge. Each was about 19" wide, squared on three sides with a concave semi-circle on the remaining side.
The underlying new plywood was sealed with Pettit Clear Sealer. Sikaflex was spread thinly over the sealed plywood and the underside of the canvas. The canvas was pressed into place, any air spaces were rolled out, and the Sikaflex was allowed a full cure. After the cure, the top of the canvas was given a good soaking with CPES. After the CPES cured, a couple of thin sanded coats of Interlux Surfacing Putty went on. This was a thin application that filled the texture of the canvas, but nothing more. That was followed with a couple of coats of feathered high-build primer paint and then the finish enamel.
This worked well for the small canvas sections that were feathered into the original canvas. No problem of any kind during the six years since the job was done. But, I like the CCABC methods for replacing cabin canvas: that's the route I'll take if I should ever need to do a replacement.
In 1955, Chris-Craft must have had access to some wide canvas, because the only sign of seams on my boat are on the cabin side not far from the rear sliding window. That's got to be more than 60". The seams look like slightly sunken lines.
Here is a shot of the original canvas covered cabin and 19" hatch. It's just the original canvas repaired in a few areas with brads, a little Marine Tex on one corner, Sikaflex, Pettit Clear Sealer, high build primer and paint.
About six years ago I used a different way of working with canvas in a very small area. I obtained an authentic Chris-Craft 19" deck hatch from eBay, spent about two months restoring this beautiful thing in the garage and used it replace a very ugly homebrew rectangular hatch someone put on the forward deck.
The framing and deck work needed to do this was the best work I've done on the boat so far. The deck pitch and crown was the complicating factor. It's a long story, but I'll cut through the woodwork and get to the chase: the hole left by the old hatch was a rectangular void much bigger than the round hatch I was going to install.
I left the old deck canvas on the forward deck intact. When the woodwork was done, I had two pieces of canvas to install around the base for the hatch hinge. Each was about 19" wide, squared on three sides with a concave semi-circle on the remaining side.
The underlying new plywood was sealed with Pettit Clear Sealer. Sikaflex was spread thinly over the sealed plywood and the underside of the canvas. The canvas was pressed into place, any air spaces were rolled out, and the Sikaflex was allowed a full cure. After the cure, the top of the canvas was given a good soaking with CPES. After the CPES cured, a couple of thin sanded coats of Interlux Surfacing Putty went on. This was a thin application that filled the texture of the canvas, but nothing more. That was followed with a couple of coats of feathered high-build primer paint and then the finish enamel.
This worked well for the small canvas sections that were feathered into the original canvas. No problem of any kind during the six years since the job was done. But, I like the CCABC methods for replacing cabin canvas: that's the route I'll take if I should ever need to do a replacement.
In 1955, Chris-Craft must have had access to some wide canvas, because the only sign of seams on my boat are on the cabin side not far from the rear sliding window. That's got to be more than 60". The seams look like slightly sunken lines.
Here is a shot of the original canvas covered cabin and 19" hatch. It's just the original canvas repaired in a few areas with brads, a little Marine Tex on one corner, Sikaflex, Pettit Clear Sealer, high build primer and paint.
1955 26' Chris-Craft Sedan Cruiser with Fly Bridge
Dan,
I think Chris Craft used that same hatch on pre-war cruisers. My 1960 model has one just like it too.
I was with Chris Smith this morning and wish I would have thought to ask him about the original method of applying the canvas. I passed up the chance. I'm thinking he would have had the answer. Rats!
Someone must produce canvas that's wider than 60". Do large tents have seams every 4 or 5 feet or so? Mine has an original seam down the middle with a 3/4" wide stainless rub rail covering it. My neighbor's '62 Connie has 2 seams (wider beam).
Al
I think Chris Craft used that same hatch on pre-war cruisers. My 1960 model has one just like it too.
I was with Chris Smith this morning and wish I would have thought to ask him about the original method of applying the canvas. I passed up the chance. I'm thinking he would have had the answer. Rats!
Someone must produce canvas that's wider than 60". Do large tents have seams every 4 or 5 feet or so? Mine has an original seam down the middle with a 3/4" wide stainless rub rail covering it. My neighbor's '62 Connie has 2 seams (wider beam).
Al
You are a lucky man to have access to the knowledge of Chris Smith.
I did some looking around in "Chris-Craft, The Essential Guide." It looks like those 19" round wood, brass and glass hatches appeared in the mid to late thirties and were made unchanged until around 1964. The brass was made by the same shop that made most of the CC deck hardware. I'm trying to remember but mine has the hull number of a cruiser built in the late 30's.
If Chris-Craft was using a lot of canvas on an industrial scale, they probably had access to larger sizes. I've seen old textile mills that produce material on very large spools. The material is then cut to stardardized sizes. What the fabric stores sell may be a small part of those spools.
I did some looking around in "Chris-Craft, The Essential Guide." It looks like those 19" round wood, brass and glass hatches appeared in the mid to late thirties and were made unchanged until around 1964. The brass was made by the same shop that made most of the CC deck hardware. I'm trying to remember but mine has the hull number of a cruiser built in the late 30's.
If Chris-Craft was using a lot of canvas on an industrial scale, they probably had access to larger sizes. I've seen old textile mills that produce material on very large spools. The material is then cut to stardardized sizes. What the fabric stores sell may be a small part of those spools.
1955 26' Chris-Craft Sedan Cruiser with Fly Bridge
-
Bill Basler
- Posts: 1996
- Joined: Thu Oct 20, 2005 4:48 pm
- Location: Cedar Rapids, IA
I've been reading this thread with interest. In Al's prior post, in which he talked about borate, I never gave much thought to the discussion until Dan mentioned a smelly dairy based product. Now, I had the light go on.
As an art student in college and studying the painting techniques of the Old Masters, we learned a lot about pigments and the make-up of paints. Long, long before synthetics, pretty much every adhesive had plant or animal based ingredients. You have probably all heard of "hide glue" for example.
Well, one of the things that art students do, is learn how to properly prepare canvas for painting. The most common method today is to use Gesso. Modern Gesso is a mixture of calcium carbonate and acrylic polymers. Old Masters Gesso, would have been something like gypsum, mixed with hide glue.
The paints of the Old Masters tended to use a protein as a binder. If you've ever tried to remove a dried raw egg from anything, you'll understand the power of these protein-based binders.
In early paints—egg temperas, for example, a raw egg white was actually used as a carrier for the pigments. The egg is what made the paint stay "bind". There were also casein-based paints. A casein is the primary protein found in dairy products.
So, I just had this revelation. I'll bet the mystery substance used to glue the canvas was a casein based product, an excellent adhesive, long before synthetics came to be. I am even guessing that Elmer's Glue (Borden) was a casein-based product before acrylic polymers were invented.
So, these Chris-Craft guys were pretty smart. Who would know how to treat canvas better than Renoir, DaVinci, and Michelangelo?
By the way, the upside of protein-based paints is that they are incredibly stable...at least as it relates to color fastness. On the downside, they get literally hard as a rock over time. That is why the paintings of the Old Masters are plagued by cracking. If the canvas gets flexed, even a minute amount, the protein-based binders will crack.
As an art student in college and studying the painting techniques of the Old Masters, we learned a lot about pigments and the make-up of paints. Long, long before synthetics, pretty much every adhesive had plant or animal based ingredients. You have probably all heard of "hide glue" for example.
Well, one of the things that art students do, is learn how to properly prepare canvas for painting. The most common method today is to use Gesso. Modern Gesso is a mixture of calcium carbonate and acrylic polymers. Old Masters Gesso, would have been something like gypsum, mixed with hide glue.
The paints of the Old Masters tended to use a protein as a binder. If you've ever tried to remove a dried raw egg from anything, you'll understand the power of these protein-based binders.
In early paints—egg temperas, for example, a raw egg white was actually used as a carrier for the pigments. The egg is what made the paint stay "bind". There were also casein-based paints. A casein is the primary protein found in dairy products.
So, I just had this revelation. I'll bet the mystery substance used to glue the canvas was a casein based product, an excellent adhesive, long before synthetics came to be. I am even guessing that Elmer's Glue (Borden) was a casein-based product before acrylic polymers were invented.
So, these Chris-Craft guys were pretty smart. Who would know how to treat canvas better than Renoir, DaVinci, and Michelangelo?
By the way, the upside of protein-based paints is that they are incredibly stable...at least as it relates to color fastness. On the downside, they get literally hard as a rock over time. That is why the paintings of the Old Masters are plagued by cracking. If the canvas gets flexed, even a minute amount, the protein-based binders will crack.
Bill Basler
Bill,
Sounds like you might be onto something there. I'm thinking the name "Airball" may have been a nick-name for whatever kind of dairy byproduct CC used to size the canvas. It may have been an early version of Elmer's Glue that Bordon supplied by the train load.
What ever it was I'm thinking it had to be a slow-setting substance that not only sized the canvas but also shrunk it. It had to stay slimy for a while in order for the canvas to shrink and tighten in the process before it stuck.
I don't think the canvas was actually glued down as such. The original canvas that's left on my boat doesn't appear to be stuck. I removed some trim and carefully peeked under the stuff. No glue.
One observation, however, in preparing the cabin top this fall was traces of trowel marks that may have been used to spread the product on the roof. A prior owner removed the canvas and merely painted over what was left. I stripped the paint using a heat gun which didn't disturb the trowel imprints. Don't know, there may have been vinyl on there between the original canvas and the paint job though. There was some old vinyl on the forward deck before I rebuilt it and covered it with Nautolex (soon to be gone).
John DeVries commented on sizing canvas prior to applying oil base paint as well. He said the oils would deteriorate the canvas if you don't. I just hope the Disodium Octoborate I used sized it enough to last a while. (If it lasts 50 years I could celebrate it on my 114th birthday).
Al
Sounds like you might be onto something there. I'm thinking the name "Airball" may have been a nick-name for whatever kind of dairy byproduct CC used to size the canvas. It may have been an early version of Elmer's Glue that Bordon supplied by the train load.
What ever it was I'm thinking it had to be a slow-setting substance that not only sized the canvas but also shrunk it. It had to stay slimy for a while in order for the canvas to shrink and tighten in the process before it stuck.
I don't think the canvas was actually glued down as such. The original canvas that's left on my boat doesn't appear to be stuck. I removed some trim and carefully peeked under the stuff. No glue.
One observation, however, in preparing the cabin top this fall was traces of trowel marks that may have been used to spread the product on the roof. A prior owner removed the canvas and merely painted over what was left. I stripped the paint using a heat gun which didn't disturb the trowel imprints. Don't know, there may have been vinyl on there between the original canvas and the paint job though. There was some old vinyl on the forward deck before I rebuilt it and covered it with Nautolex (soon to be gone).
John DeVries commented on sizing canvas prior to applying oil base paint as well. He said the oils would deteriorate the canvas if you don't. I just hope the Disodium Octoborate I used sized it enough to last a while. (If it lasts 50 years I could celebrate it on my 114th birthday).
Al
While working with this old canvas I've done some snooping under the exposed edges. Something with a light adhesive quality was used under the canvas. Surprisingly, the underlying wood shows no evidence of paint or oil-based sealers of any kind.
Whatever the adhesive or sizing was, very little sign of it remains after all of the years. On some of the edges of this material, the bond has broken away or seepage from varnish or paint has re-established a bond. The edges are the first to break loose.
When installing the deck hatch I had to do some trimming of canvas and wood in an area far away from any edges. I used a small screwdriver to lift a little of the canvas and it was definitly stuck to the wood with something. There was a trace of some light colored powder residue as well.
When I work with loose canvas areas I'll do something to glue it down again before finishing up. If the area can be clamped or weighed down with something, I use Sikaflex. If it's a vertical surface I've used Tight Bond wood glue. It shrinks up while it dries.
There are two kinds of duck canvas in our fabric store. They call it "heavy duck", and "duck" canvas. The canvas used by CC is a little thinner than the fabric store "duck canvas."
As an aside, natural heavy duck canvas made excellent curtains for the cabin windows. This stuff shrinks a lot, so pre-wash it and hot dry in a dryer before you cut it. Treat with Scotch Guard. Very nautical-looking.
Whatever the adhesive or sizing was, very little sign of it remains after all of the years. On some of the edges of this material, the bond has broken away or seepage from varnish or paint has re-established a bond. The edges are the first to break loose.
When installing the deck hatch I had to do some trimming of canvas and wood in an area far away from any edges. I used a small screwdriver to lift a little of the canvas and it was definitly stuck to the wood with something. There was a trace of some light colored powder residue as well.
When I work with loose canvas areas I'll do something to glue it down again before finishing up. If the area can be clamped or weighed down with something, I use Sikaflex. If it's a vertical surface I've used Tight Bond wood glue. It shrinks up while it dries.
There are two kinds of duck canvas in our fabric store. They call it "heavy duck", and "duck" canvas. The canvas used by CC is a little thinner than the fabric store "duck canvas."
As an aside, natural heavy duck canvas made excellent curtains for the cabin windows. This stuff shrinks a lot, so pre-wash it and hot dry in a dryer before you cut it. Treat with Scotch Guard. Very nautical-looking.
1955 26' Chris-Craft Sedan Cruiser with Fly Bridge
-
Bill Basler
- Posts: 1996
- Joined: Thu Oct 20, 2005 4:48 pm
- Location: Cedar Rapids, IA
My guess is that the canvas was fairly well saturated with this mystery substance. As yzer notes, this canvas will shrink quite a lot. If the substance was casein, this would have served as a glue and and a sizing. Over time, as the casein turned brittle, it looses its ability to stay adhered to a wood structure that's expanding and contracting.
Here are a couple of interesting links:
http://www.wackyuses.com/experiments/plasticmilk.htm
http://www.bordenchem.com/aboutUs/history.asp
Here are a couple of interesting links:
http://www.wackyuses.com/experiments/plasticmilk.htm
http://www.bordenchem.com/aboutUs/history.asp
Bill Basler
Thanks, Bill & Dan,
It looks like Bordon was into making synthetic resins in the 30's after acquiring Casein Company so it's possible that the "Airball" stuff was a combined product with some synthetic resins added for stability.
Plastic Milk! I'm going to copy that for my wife's 8th grade science class. She's always looking for interesting things to do with them. Hey, maybe they could produce enough for my forward deck project. Hee Hee.
I have gobs of untreated canvas left over from the roof job. The curtain idea sounds like a good way to make use of it.
Al
It looks like Bordon was into making synthetic resins in the 30's after acquiring Casein Company so it's possible that the "Airball" stuff was a combined product with some synthetic resins added for stability.
Plastic Milk! I'm going to copy that for my wife's 8th grade science class. She's always looking for interesting things to do with them. Hey, maybe they could produce enough for my forward deck project. Hee Hee.
I have gobs of untreated canvas left over from the roof job. The curtain idea sounds like a good way to make use of it.
Al
Canvasing a Deck
I did the hard top and cabin top on my '58 30' seaskiff years ago. I used a canvas bedding underneath. I think it was fairly close to good old bedding compound thinned to gooey consistancy. You spread the stuff with a towel and work fast so the thinner doesn't evaporate out. I layed the canvas in the stuff an pulled and rolled out the air and stapled and tacked it around the edges.
I had a choice here. I could use the old timer's method of shrinking down the canvas - just saturate it with water and bake it in the sun or do what they do with canvas cover airplane wings and "dope" it. I chose to use the dope. You can get the stuff from aircraft supply places. Petit used to sell it as canvas sealer. It dries in a flash so you can re-coat as fast as you put it on and shrinks really tight. After that I built up the paint with plain old flat white. I thinned the first few coats to get it to dy faster. Then keep pilling it on. Gloss enamel to finish.
That was a beautiful - original - finish. The local tent and awning shop still has 12' and wide canvas in stock. Belle Isle Tent and Awning, Detroit, MI on Jefferson Ave.
I had a choice here. I could use the old timer's method of shrinking down the canvas - just saturate it with water and bake it in the sun or do what they do with canvas cover airplane wings and "dope" it. I chose to use the dope. You can get the stuff from aircraft supply places. Petit used to sell it as canvas sealer. It dries in a flash so you can re-coat as fast as you put it on and shrinks really tight. After that I built up the paint with plain old flat white. I thinned the first few coats to get it to dy faster. Then keep pilling it on. Gloss enamel to finish.
That was a beautiful - original - finish. The local tent and awning shop still has 12' and wide canvas in stock. Belle Isle Tent and Awning, Detroit, MI on Jefferson Ave.
Who is online
Users browsing this forum: No registered users and 9 guests