Taping seams on old tent

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Blackredgold1964
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Joined: 21 Dec 2007, 11:03pm

Taping seams on old tent

Post by Blackredgold1964 »

Dear All,
I’m doing maintenance on a 30ish year old tent after the tapes on the seams on the inside of the outer tent have come loose. I read about tape you can iron on but found that way too complicated. I got McNETT’s SEAMGRIP (‘Seam sealer&repair adhesive for holes&tears in flexible materials’), thinking I can brush over the seams, on the outside. Turns out you do it to the inside of the tent. The instructions suggest that prior to applying SEAMGRIP, to clean the seams with isopropyl alcohol. As I’ve had methylated spirit (for fondue burner) at home and found out that it’s quite similar to isopropyl, I started on a small patch as on the photo. The meth however seems to take the sliver coating away, see photo, treated patch in the middle, to the right the loose seam, to the left the outside of that tent.

P1150434.JPG


Some questions:
Would isopropyl alcohol (aka rubbing or surgical alcohol) be kinder to the sheet?
Even if, would I likely to be doing more damage than good?
I don’t really want to put that much work into it but should I go the whole way and get some ironing-on tape (but I’d still have to clean the seams first)?
Ideally I’d simply spray it with something like Nikwax Tent and Gear SolarProof
I’ll be setting the tent up now to test with water. If nothing leaks, then I’d maybe just cut off all the old tapes?
At some stage I must have used some material to reseal, as on this photo.
P1150435.JPG

This seems to be rock solid now that I suppose I best leave it on as it is, rather than risking damage when trying to remove it?
I don’t know the exact material, especially the silver coating on the inside, but the tent is called Globetrotter K2, polyester, so I assume that’s the material. I bought it in a German department store. My daughter took it for a 4 day festival last year and intends to do the same again next month, hence the preparation now.
I did a bit of research, also via this post, viewtopic.php?f=42&t=122327 but any additional advice would be welcome.
Thanks for reading this far.
Blackredgold1964
Blackredgold1964
Posts: 100
Joined: 21 Dec 2007, 11:03pm

Re: Taping seams on old tent

Post by Blackredgold1964 »

So, stress testing completed and the result doesn’t provide confidence although the weak link seems now to be a different one. Had it sprayed with water and was sitting inside the tent. Wherever I moved, I got wet – I assume the groundsheet is porous everywhere. The little bit of water that runs off the flysheet and onto the grass seems to cause this, plus the moist grass itself. Looking at the low sides of the groundsheet it looks a little brittle or transparent in places.
On the plus side, although I could see some drops coming through, there does not seem to be major leaking at the seams.
As for the groundsheet, I noticed these recommendations - Fabsil Gold Aerosol, https://grangers.co.uk/products/fabsil-gold-aerosol
Any thoughts would be welcome, plus some pictures.

inner and outer tent
P1150437.JPG


P1150439.JPG


P1150442.JPG
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pjclinch
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Re: Taping seams on old tent

Post by pjclinch »

The coatings on tents that make them waterproof, particularly the groundsheet, tend to involve the sort of application that you can't rellay replicate at home. Notably, the sheet is used as a basis for a continuous layer of molten PU: it's the PU that keeps out the water and the fabric is, I think, just something to bind it all together.
Put another way, once the groundsheet has got porous you're really looking at a new groundsheet. Putting a waterproof footprint underneath a porous groundsheet isn't the answer many hope, because without bathtub sides it's easy for water to get between the two and then the footprint just helps push it through the top.

And a new groundsheet is non-trivial (sourcing the right material, cutting it to shape and sewing it in, or stamping up the readies to have it done professionally), so it might be the time to cut your losses given the age of the tent.

The seam tape, I'd be inclined to just do it with goop rather than add more tape. The main reason for seam tape is vendors can proudly announce "100% waterproof", but applying it weakens the flysheet as well as adding a little weight and bulk. Taking the time to goop the seams should stop any leaks, and it's much easier to reapply than seam tape.

Pete.
Often seen riding a bike around Dundee...
Blackredgold1964
Posts: 100
Joined: 21 Dec 2007, 11:03pm

Re: Taping seams on old tent

Post by Blackredgold1964 »

Thank you Pete, for that well informed reply. It makes decisions now much easier. I think I won't invest any more effort into this tent. As 'plastic waste' has finally become such a big topic it's a great shame that it's not worth sewing a new groundsheet into it, and keep using the tent. but for now I'm able to make the next step.
Thanks again.
crazydave789
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Re: Taping seams on old tent

Post by crazydave789 »

you can't prevent damage when removing old seam tape whether fabric or the PU type.

the cheapest fix is the silicone and white spirit solution, I use a thick solution on the inside where the tape comes away then on the outside a thinner solution which soaks into the seam and stitching for a non shiney look.

I've couple of items with PU tape that strips an inch wide strip from the coating, I sometimes which you could specify non taped seams so you could do it yourself properly.
Blackredgold1964
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Joined: 21 Dec 2007, 11:03pm

Re: Taping seams on old tent

Post by Blackredgold1964 »

Thank you crazydave789, I'll keep a note of all the home made solutions, including the goop stuff mentioned by Pete. I have another tent in the attic and might come back to some of those DIY solutions.
mercalia
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Re: Taping seams on old tent

Post by mercalia »

you might try some of this stuff
plastidip
I have been thinking of renovating my old Karrimor panniers (which used to have some thing similar ) with the stuff as it is a flexible rubber skin

https://www.ebay.co.uk/itm/PlastiDip-Plasti-Dip-Rubber-Paint/151047448649?ssPageName=STRK%3AMEBIDX%3AIT&var=450177784917&_trksid=p2060353.m1438.l2649
Blackredgold1964
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Re: Taping seams on old tent

Post by Blackredgold1964 »

Interesting, thanks, mercalia.
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pjclinch
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Re: Taping seams on old tent

Post by pjclinch »

Blackredgold1964 wrote:Thank you crazydave789, I'll keep a note of all the home made solutions, including the goop stuff mentioned by Pete. I have another tent in the attic and might come back to some of those DIY solutions.


Note that "goop" is just my generic term for some kind of sealer rather than a specific product. In the past I've just wandered in to a good outdoor shop and asked if they had any seam-sealer (been the best part of 20 years since I last did any). McNett's seem to have a pretty good reputation in this line, but I'm passing on hearsay with that rather than direct experience.

Pete.
Often seen riding a bike around Dundee...
mercalia
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Re: Taping seams on old tent

Post by mercalia »

I was looking at their advert it seems they have some goo particlurly for seams - PLASTISEAM

"Plastiseam is a weatherproof seam sealer!
Plastiseam is a flexible sealant, designed to weatherproof seams in outdoor equipment.
It is easy to apply, and dries really quickly.
Excellent for sealing out moisture caused by pin holes in sewn seams, in most fabrics.
Waterproofs seams on camping gear, awnings, sails, backpacks, rain suits and a lot more.
Seals out wind and dirt.
Will not become brittle.
Plastiseam formula is great on all nylon and synthetic fabric seams.
You are bound to find hundreds of uses for this unique product!
Plastiseam is second to none in performance and will last far longer than any other seam sealer on the market."

https://www.ebay.co.uk/itm/PlastiSeam-Seam-Sealer-Weatherproof-Tough-Flexible-Sealant-Clear/311664951901?hash=item4890adc25d:m:mAP_lOE8UeWbuG6TvCajD2A

seems abit expensive but the advert seems to show a smaller packet than advertised for sale

There is a cheaper alternative called SEAM GRIP
https://www.blacks.co.uk/activities/101553-mc-nett-seamgrip-outdoor-repair-28g.html/368944/?istCompanyId=d92b362f-ac8a-4a8a-87ca-c56eafad7955&istItemId=raxlaqxax&istBid=tzlt&gclid=EAIaIQobChMI5bzxyoTP2wIVqbXtCh2qng8LEAQYBSABEgJtQfD_BwE&gclsrc=aw.ds

[youtube]2doJ92EgTN4[/youtube]
Blackredgold1964
Posts: 100
Joined: 21 Dec 2007, 11:03pm

Re: Taping seams on old tent

Post by Blackredgold1964 »

Good you clarified, Pete, I thought you meant goop specifically for bike/bicycle tubes
https://www.amazon.co.uk/Goop-Puncture- ... B004EK5P4I
crazydave789
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Joined: 22 Jul 2017, 10:21pm

Re: Taping seams on old tent

Post by crazydave789 »

silicone white spirit mix can seal old and new kit, thin it down and its good for rucsac type fabrics to make them repellent as well as sealed or PU backed tent fabric. thicken it up and its good for seams and groundsheets.n apply with a sponge or a brush and wipe off any drips.

budget silnylon or even silcotton.

I've some coffin tents that need their seams doing and a set of AGU fabric panniers I want to proof up this year.
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