Waterproofing a homemade tarp

[BushBob]

All,

I've bought some lightweight, ripstop, nylon with a view to making a tarp. It isn't waterproof so I'll need to treat it with something. I'm looking for robust waterproofing rather than breathability.

Has anyone done anything similar and, if so, what works best?

Thanks in advance.

Bob

 

[crosslandkelly]

50/50 Silicone white spirit mix, is one I have heard of.

 

[Whittler Kev]

I've made both of the 2 I use out of ripstop. I used the tent waterproofer from Halfords. It stops a lot but drips if you have a puddle form, It also is still breathable so lets a little wind through but looks like a sail in a good blow . I found that thin (1mmish) bungee on the tie outs stops it stretching or ripping

 

[John Fenna]

On the tarp I made from downproof 100% cotton cambric (pillowcase linings) I just used Fabsil... works a treat...

 

[bilmo-p5]

Fabsil will be fine on uncoated nylon.

 

[BushBob]

Thanks for the info. on this. I'll give Fabsil a go.

I'd thought about using some thin bungee on tie downs and will definitely do that now.

Cheers,

Bob

 

[GadgetUK437]

I reckon you'll find 1mm shockcord a bit thin!
3mm at least.

 

[Whittler Kev]

I reckon you'll find 1mm shockcord a bit thin!
3mm at least.

1mm works for me. I'd sooner snap the shockcord than rip the tarp. I use it inbetween the guy rope and the tarp

 

[Whittler Kev]

On the tarp I made from downproof 100% cotton cambric (pillowcase linings) I just used Fabsil... works a treat...

yo John. What size did you make and how small does it pack?
My ripstop is 10'x14' and fits in a bag about 10"x6"

 

[John Fenna]

4x3m - but I have yet to measure it packed at I "stuff" it - not fold it - into a stuff sack. This stops repeated stress being put on the same areas ..like you pack a sail...
It packs about the same size as a Tatonka poly cotton of the same kind of size...

 

[Whittler Kev]

4x3m - but I have yet to measure it packed at I "stuff" it - not fold it - into a stuff sack. This stops repeated stress being put on the same areas ..like you pack a sail...
It packs about the same size as a Tatonka poly cotton of the same kind of size...

A lot larger than a ripstop then...but a lot more durable I reckon
BTW I stuff too for the same reason

 

[John Fenna]

I am trying to get all my kit - as much as is possible in this day and age - to be "naturals" ie no oil derived products. Yeah - I know it is next to impossible (ie I use fabsil!) but I am trying for minimal impact combined with absolute performance!

 

[mousey]

A good while ago I made a tarp from 1.1oz ripstop untreated nylon, it was 'seconds' @ 1 per metre there was nothing really wrong with it just some of the ripstop lines were a bit uneven at some points - not good enough to make something commercially with.

Anyway I used fabsil gave it a couple of coats and under heavy, heavy rain it let a light mist through - after a 10 hour night things were getting wet. Maybe not enough fabsil, maybe the fabric was too light / loose a weave and just let a little moisture through? I don't know. I've recently bought a commercially made tarp as I found a long and thin one which is my preference for a tarp.

I've heard people making their own mixture of silicone sealant and white spirits, I've also heard of people use brick sealant.

 

[Scotty Von Porkchop]

To make a decent waterproof tarp from nylon ripstop you'll need a tight weave. This is easily tested by trying to force your breath through it, sealing you lips on the fabric. Unless there's a significant impedance to you breath going through I wouldn't bother TBH.

 

[BushBob]

Scotty,

The stuff I've got is described as parachute material. It is supposedly made for the MoD. I'll try the breath test on it.

Thanks for the tip.

Bob

 

[Scotty Von Porkchop]

The 3' wide stuff (occasionally 4')? that's no good I'm afraid, tried it and leaked like a sieve! There is some of the MOD ripstop that I use for hammocks (5' amd 1.3oz/y2) that will work, easily spotted as this one is shiny, I've no idea if that's a parachute material though

 

[BushBob]

I've done the breath test on the fabric. It seems pretty airtight. I did manage to force some breath through, but there was a lot of resistance. Think I might give it a go.

 

[Scotty Von Porkchop]

Sounds promising, good luck