Waterproofing Canvas Tents?

[Ranger58]

I've had a GP-Small now for almost 2 yrs now and after a less than spectacular first outing I attempted to waterproof it with Thompson's Waterseal.  It did absolutely nothing to prevent the water/rain from coming in not only on the seams but through the canvas as well.  Does anyone have an idea on how to save this tent?  I really like the tent; but in it's current state I can't use it.  Thanks in advance for any suggestions or ideas.

[chanumpa]

Can-Vak,but it is kind of smelly.Its the old military style stuff,but it does work.

[Orion]

I'm not familiar with that brand, but have you wet down the canvas with a hose?  I've had several canvas tents and none of them leaked after wetting them down, ever.

[Pointer]

what chanumpa said...Cabela's sells it by the gallon...

[Bjorn]

What Orion said! Never used anything but water to waterproof a canvas tent.

[TommyBoy]

Yep, Can-Vak is good.  Usually you can get it at most Army-Navy Surplus stores.

I can't believe the Thompsons didn't do anything though - how did you apply it?

[Sam McMichael]

I went to several outdoor stores and found several brands of spray on treatment at fairly reasonable prices. I can't comment on results yet, because it has not been out in the rain.

[reddogge]

Can-vak!!!!!

[mark stella]

Ranger, is your tent the old canvas or the newer nylon canvas? I have the newer nylon GP small. I have used it several years now. Mine has yet to be treated. I do however use 6 mil clear plastic sheeting over the top for extra protection from the snow and rain. I tie it off on the upper guide ropes. It holds the heat in a little extra too.

[mark stella]

Here is mine set up. Warm, dry, and comfortable.  

[Flinttim]

You say it's canvas but that's a general term. Cotton ? Man made fiber?. Simple truth is, if you put Thompsons on it you are basically screwed. Even Thompson does not recommend their product for canvas. Normally man made fiber tents need (if at all ) the seams sealed now and then.
 Treating with Thompsons does not do much but create a very large candle. It's not much more than paraffin dissolved in a solvent . Spray it on and the solvent evaporates and the wax left behind. If that thing catches fire, it will burn faster than you can get out of it.In 41 years in the boat canvas business, I've seen it all.

[Ranger58]

Tommyboy, Flinttim, it is the cotton canvas style tent, dated on the instructions was 1954 updated 1958.  It was brand new in the bag when i bought it!  The first excursion my tent got the full water treatment, didn't need the waterhose.  It rained non-stop for quite some time and the canvas didn't swell at all it just ran right through the material.  Flinttim, a best friend has a GP medium that has several applications of thompson's done with a garden sprayer and it has worked like a dream for him
I've got one application on mine with a garden sprayer with about two and a half gallons of sealer on the tent.  Thinkin about gettin a power sprayer and sprayin it down to remove the thompson's and starting over

[lone hunter]

If you have a stove-jack going through the canvas roof, you should know that Thompsons is flamable. Doesn't take much of a spark to set things off. Lost a tent roof using it. No problem for years using it outfitting but once is enough. Called Thompsons and they said not to use it around flame. Can-vac much better option. Just a thought. Mike

Some types of canvas hold no more water back than a pair of blue jeans and need something to keep out the water. My tents are made of Egyptian sail canvas from Backel canvas and they never leak and are not treated with any thing, other than one time an idiot sprayed bug dope at my campfire canoe tripping tent when it was rolled up. The folks at Beckel said to gently wash it with mild dish soap, if it still leaked spray that area lightly with Scotch Gaurd, it worked.  If you have sprayed your tent with Thompsons Water Seal and are planning on having fire in it or near it, wash it with soap and try to get that waxy oi8ly stuff off. Then use Aqua armor for natural fabrics to water proof it.

[Bjorn]

We have camped for weeks in my canvas tent in the worst snow, wind, and rain you can imagine- Wash state rain, Oregon rain, and Utah snow. A good canvas tent needs nothing but water and love! Put it away dry is the main rule.

[northener]

Thompsons water seal is nothing more than mineral spririts. Watered down mineral spirits besides.  Junk!!!!!!!!!!