Canvas Tarps

[Nomad]

Good idea, I think I'll give that a go... Do you think a few coats of Fabsil would be enough to proof it?

I think that would depend on the weave of the cloth. So far as I can tell, Fabsil puts a hydrophobic finish on the fibres, but if the fibres aren't sufficiently tightly woven, it isn't necessarily going to stop water getting through. (To take it to the extreme, you could weave a net from cotton string and soak it in Fabsil to prevent the fibres from saturating, but it won't turn the net into a water bucket.)

 

[Big Stu 12]

Has anyone thought about using Calico?

 

[Nomad]

I am in the middle of making a tarp from a dropcloth - I will let you know how it works out!

How windproof is it? (My standard test is to hold it up to the mouth and try to blow through - curtain lining material is rubbish, Tilley hat is very good.)

 

[John Fenna]

How windproof is it? (My standard test is to hold it up to the mouth and try to blow through - curtain lining material is rubbish, Tilley hat is very good.)

It seems fairly tight and wind resistant - so should work - I hope!

 

[copper_head]

Hmmm... Dust cloths here I come I think

 

[crosslandkelly]

Good idea, I think I'll give that a go... Do you think a few coats of Fabsil would be enough to proof it?

I think it would. It would be easy to test with the garden hose.

 

[crosslandkelly]

I think that would depend on the weave of the cloth. So far as I can tell, Fabsil puts a hydrophobic finish on the fibres, but if the fibres aren't sufficiently tightly woven, it isn't necessarily going to stop water getting through. (To take it to the extreme, you could weave a net from cotton string and soak it in Fabsil to prevent the fibres from saturating, but it won't turn the net into a water bucket.)

The weave on the good cotton dust sheet that I use at work, seem pretty tight. There i also a vid on youtube. of a guy proofing a sheet with silicone. I'll try to find it later.

 

[mousey]

Good idea, I think I'll give that a go... Do you think a few coats of Fabsil would be enough to proof it?

A while ago I made a tarp out of some light weight nylon, and proofed it with fabsil. A year later I took it out and it rained, while it stopped the rain ok-ish when it was heavy it forced it's way through as a very fine mist, that's alright for a bit but after a couple of hours even a fine mist can get things soaking. So I guess I'd need to keep re-proofing it - or I didn't put enough on in the first place - or [as in a previous post] the material is just too porous in the first place.

I have heard of folks mixing silicone and white spirit to make a sealant, also using a brick weather sealant on cloth materials.

 

[John Fenna]

I have just finished sewing the brute!
It is large - about 12'x10' - and was a nightmare to feed through the machine and this fact plus its weight and bulk made sewing the reinforcing tape around the hem and lumpy centre seam a big hassle (with some distinctly unstraight rows of sewing!).
So far it has cost me 4 needles broken - about £2 - £5 ish in thread, £10 for the cloth, £3.50 for the tape and £23 for the Fabsil.... so more than a nylon MOD tarp already - never mind my time.
And I am yet to find out if it is waterproof!
I will be applying the Fabsil over the weekend.....

 

[treadlightly]

Good luck John, let us know how you get on.

 

[Nomad]

Any thoughts on oiling or waxing the cotton? That strikes me as a good way to get it waterproof in the long term, may well help with rot/mildew resistance, and might make it more resilient to sparks as well. It will add weight, although I don't know how much (any guesses?), and is no doubt a bit of a pain to do.

 

[John Fenna]

I was intending to use a mix of linseed oil and beeswax - but I want to be able to lift it unaided and decided Fabsil might be lighter!
If fabsil fails then wax it is!

 

[mountainm]

I was intending to use a mix of linseed oil and beeswax

That would've been one huge candle wouldnt it?

 

[Nomad]

I'm looking into a 3x3 made from 8.5oz cotton, which I think is lighter than the dust/drop sheets. Dry, it should work out to about 6lb, so I need to get an idea of how much the waxing would add.

 

[Gray]

I think nik wax or grangers do a spray for cotton and polycotton. Dont know how much it is though, probably a fortune

 

[woodstock]

Also a soak in borax before hand gives it some fire proof properties

 

[John Fenna]

2.5 liters of Fabsil (£23 in our local hardwear shop) did ONE SIDE!
This is getting seriously silly now!
£66 ish for a tarp that may never be waterproof and another £15 for the ridgeline and guys which I am making from natural fibre twine....

 

[mountainm]

2.5 liters of Fabsil (£23 in our local hardwear shop) did ONE SIDE!

Is that the big jerry can or the small jerry can?

By one side do you mean your doing the topside and underside?

 

[Stew]

2.5 liters of Fabsil (£23 in our local hardwear shop) did ONE SIDE!
This is getting seriously silly now!
£66 ish for a tarp that may never be waterproof and another £15 for the ridgeline and guys which I am making from natural fibre twine....

Blimey! I'm hoping it waterproofs for you!!

 

[John Fenna]

Is that the big jerry can or the small jerry can?

By one side do you mean your doing the topside and underside?

I mean one half of one side and it was the biggest can in the shop!