Paul,
It was painfully slow.
Literally hours of work with my wife and I taking a few days.
We laid out the sleeping bag on our rectangular dinning table.
I would press down on a section of the sleeping bag with both hands and "stretched" out the fabric so that the seam was in the middle of my two hands and the line of stitches was flat and taught/straight.
My wife (bless her for putting up with my anal retentiveness and compulsive behaviors!) then would squeeze out some Seam Grip Sealer onto the small brush that came with the tube of Seam Grip.
She would then lightly brush some of it along the seam.
She would carefully thin out the sealant with multiple small brush strokes.
In the beginning it was a thick, wide line of sealant.
As we got the hang of it, the line of sealant needed was just a little wider than the seam.
We made a point of making sure that there were no "dry" spots along the stitching, which would be the tell tale sign that we missed a spot….due to my not stretching the seam out with my hands.
We had to do only a few feet at a time because we had to be very careful that the parts of the bag that we had finished did not end up sticking to other parts of the sleeping bag shell or to itself if the fabric folded up on itself.
The hard part was doing the head and foot ends of the bag.
The seams along the top and bottom that went horizontally across the bag on the top and bottom (across the chest left to right) and the vertical seams that went head to foot along the zipper for example were the easy ones.
In order to seam seal the head and foot area required that I "inflate" the head area so that it could keep its shape.
To do this, I used my bear vault….sometimes a really big book like an unabridged dictionary. At times, I hand to unzip the full length zipper and reached inside the bag to use my hand to hold the "back" of the seal that I was trying to seal.
In the case of the head and foot area, I left the bear vault into the bag to keep those areas from "deflating", which could result in the seam folding over on itself and having the mess of the sealant sticking to itself….pulling those apart would tear away the Seam Grim and ruin that area.
Fortunately, that did not happen often.
The next morning, I found that the sealant was tacky/sticky to the touch.
To solve this problem was easy, but a bit messy.
Once all of the seams had been sealed (2 or 3 day process), I took the whole bag to my bath tub.
Using a small brush, I would take a small cup of baby powder and I dipped the brush into the baby powder.
Then I would lightly dust/brush the seams to coat the Seam Grip.
This would adhere to the Seam Grip and eliminate the tackiness.
This is critical….without the baby powder, I found that the Seam Grip would stick to any other part of the bag that had Seam Grip and would/could tear away the seam sealing that I had previously done.
Once I had dusted my entire bag, it had a chalky look to it….I had to shake off or beat as much of the powder off as possible.
To be honest, my bag does not look pretty anymore and my friends look at my bag as if I had ruined it.
I kinda agree with them, but fact is that I would rather have performance over looks and it isn't a beauty contest when you are out there with the bears and squirrels. :)
I am sure that this could be done with one person, but having someone else makes it go a lot faster and the results would probably be better.
Since doing this to my Helium EQ we have done this to my wife's Mountain Hardware Phantom 15 with good results…cleaner looking than my bag with smaller and tighter lines on the seam.
It is also hard on the hands to keep the fabric and seams flat and taught to allow for a good line of sealant to be put down.
Hope this helps.