Hi folks,
So, I recently purchased a second hand tent for £60 (F10 Nitro 200+). When I got home, I realised that the tents PU coating was sticky and degraded. Fortunately, the seller gave me a full refund and let me keep the tent!
So rather than throw it out, I thought why not try to repair the coating? (The new version of this tent is £400+)
This info took me a little while to put together as there are a lot of opinions on the matter of degraded PU coatings. But I thought it might be of use to someone someday so I've put together a little guide.
This guide should only be followed for PU coated tents, it won't work on Sinylon.
A bit of research threw up two options; 1) wash the tent with normal detergent to force the PU coating to delaminate 2) soak the tent in dilute ammonia to dissolve the coating.
I chose to experiment with the ammonia approach and then wash it for good measure.
Equipment:
1000ml Household ammonia 10% - I used ‘Max Strength’ from Homebase at 9.5 %
Gear Aid Tent Fabric Sealant x 2 bottles (only just enough)
Gear Aid Seam Grip + WP (polyurethane based adhesive) I had one of the extra large tubes to hand from another job (Mcnett brand £27 on eBay)
Toulene - approx. 150ml
Fabsil Gold
500ml – 1000ml Isopropyl alcohol
Talcum powder
Permatex flowable silicone (far more flexible than normal silicone and doesn’t require diluting with white spirit), ‘Seam Grip + Sil’ can also be used but costs more and maybe has a weaker bond.
Foam brush 4" or a thin foam pad
Coarse sponge
Stiff brush
Small paint brush (8mm – 10mm)
Large tub (enough for 13 liters + a tent)
Extra long rubber gloves
3M respirator mask
1) Peel off as much seam tape as you can and remove any guy lines.
2) Dilute 1000ml of household ammonia in 12 litres of warm water (wear a respirator if you value your lungs)
3) Submerge the tent completely agitate it and ensure all surfaces are covered, soak it for 10 – 15 mins, ‘stirring’ occasionally.
4) Ensure all PU coating is removed and scrub any remaining patches with a stiff bristled brush or coarse sponge
5) Rinse the tent in clean water.
6) Place the tent in a washing machine with normal detergent and wash without a spin at 30C (I added 3 extra rinse cycles) * This step can be skipped if your happy with the results of step 4.
7) Hang the tent up to dry.
8) At this point I used seam grip to repair any small holes in the tent - I used a small amount of Cotol 240 to speed up curing (2hrs)
9) This step requires a dry undercover area or a 24hr dry period. Erect the tent inside out and using a mixture or water, washing up liquid mixed 50:50 with isopropyl alcohol clean off any remaining PU coating or seam tape residue.
10) Hose down the tent to remove and liquid soap and leave to dry.
11) Once the tent is completely dry, shake your tube of Fabric Sealant and pour it into a container, using a foam brush or sponge apply an even layer to the whole tent (inner side of the outer that should currently be facing outward, if that makes sense?). This will take at least 24 hours to dry. After a couple of hours I used the remaining sealant to put a second coat on the areas that surround the inner tent.
12) This step requires rubber gloves and a respirator, Toulene is nasty stuff! Mix 3 parts Seam Grip with 1 part Toulene, this will make the seam grip easier to work with and improved curing times, only mix as much as you can use in 20 mins.
13) Cover all of the tent seams in this, as you would if seam sealing normally. Ensure that you also coat any areas of stitching i.e. guy points and peg points.
14) Once the seam grip is set apply a light dusting of Talcum powder to the whole tent to prevent surfaces sticking to one another.
15) Re-erect the tent normally and use a damp cloth to wipe down the outer.
16) Seal the outer seams with Permatex (I just smoothed it on with my finger ensuring to push it under any joins/folds near the seams). I used Permatex as my tent is a Silnylon/PU hybrid, meaning Seam Grip won’t bond to the outer as it has been treated with silicone on the exterior side. *Seam grip may work but I'd perform a small test patch first.
*This step can be skipped if your happy with the interior seam sealing, it’s just my belt and braces approach
17) Using a wide paint brush apply Fabsil Gold to the whole outer, this will take approx. 6 hours to dry.
Now go test you work (your mileage may vary)
All the best
Michael