Dry bag for sleeping mat?

[Guest]

Do you happen to have any pics of the top flap/opening of a finished bag? I read the instruction guide you posted, but I am still having a hard time visualizing what the top looks like when it is finished.

Sadly, no. All of the process photos disappeared with Community Webshots photo hosting. When the next Seattle Fabrics order arrives and I figure out what I want to make next I will take more photos along the way.

Also, it looks like 2 pieces are cut to form the bag, sealing both edges and the bottom - in other words, 2 side seams and a bottom seam. Would it be better to cut one larger piece of fabric, folded over onto itself, in which case there would only be one side seam?

Nope, and yup. One piece of heat sealable fabric is cut and folded over to form the bag. Iron the bottom seam and the folder over side seam and those two sides are done.

Lastly, once it finished, does the coated side of the fabric stay on the inside of the bag or do you turn it inside out?

The heat sealable side stays inside. So far, 7 years on, even with the DIY bags in the worst imaginable heat conditions, baking inside a closed vehicle or sun beaten atop a kayak deck in the Everglades, that heat sealable side has not “melted” or adhered to any contents. I think it takes a lot more heat and pressing down to make anything happen on the heat sealable side.

Once ironed together that material makes a helluva tenacious seam. We tried tearing apart some timed test strips of 1 inch wide x 6 inch long fold-over loops. with a 1 inch x 1 inch heat sealed area; I could forcibly (hurt my fingers) pull the 5 and 10 second pressed iron pieces apart, but after that iron duration it wasn’t gonna happen. 30 seconds to 1 minute is not coming apart, and the material doesn’t start to scorch until 2 minutes +.

I will sweeten my top template pattern offer; I’ll include a test strip of heat sealed material to try to pull apart. We tested everything from 20 seconds to 3 minutes iron pressing time.

Back to hand sanding birch. I’ve got blisters on me fingers!

 

[flyingbison]

Back to hand sanding birch. I’ve got blisters on me fingers!

Those blisters should be treated by holding a cold beverage.

 

[latremorej]

NRS sells a really long one.

 

[Odyssey]

I'm gonna sound like a tight Scotsman asking this, so I know Mike will understand, but how much does it cost approximately to make a bag with this fabric, comparable to store bought ready made bags? Big cost saving? Negligible? None?
This fabric is incredible stuff. Thanks for this Mike.

 

[Guest]

I'm gonna sound like a tight Scotsman asking this, so I know Mike will understand, but how much does it cost approximately to make a bag with this fabric, comparable to store bought ready made bags? Big cost saving? Negligible? None?

The heavier weight fabrics come in 58 inch wide rolls. Fabric costs run $14.95 a yard for 70 Denier Tafetta to $21.50 for the heaviest 430 Denier Packcloth.

http://www.seattlefabrics.com/dry_bag.html

For funsies I pulled out the template for a large Therma-Rest pad; material needed = 44 inches x 25 ½ inches, so one yard will make a sleeping pad bag with lots of excess. The bag for my giant camp chair required a piece 58 inches x 29 inches, so again one yard will do.

Add the cost of webbing and side release buckles and dang near any size bag can be made for a little over $20, even using the heaviest weight packcloth.

I don’t know how much a bag for a 30 inch wide sleeping pad costs, or if one that tall even exists, and I’ve never seen one sized to accommodate a large folding camp chair. We did look at the price for a manufactured dry bag for the guitar. Jeeze Louise; this was lots less expensive:

http://www.joesacher.com/blog/how-to/creating-a-dry-bag/

For anything that needs a dry bag in an unavailable size, or for a custom sized or custom shaped dry bag the heat sealable fabric is the easy solution. A SealLine Kodiak tapered bag is $60 and the heat sealable packcloth is much thicker and more durable.

https://www.amazon.com/SealLine®-Kodiak-Taper-Dry-Wide/dp/B0013FPENO

 

[Odyssey]

Thanks Mike. I'm not sure what I'd use this for yet ( already thinking thwart bags? ) but the possibilities seem endless.

 

[Guest]

I forgot to mention we made all of the sleeping pad bags a little extra long. I carry a pillow case to stuff with spare clothes, sometimes even a small pillow, and a sheet in hot weather camping. I stuff those things in the bag atop the pad. Instead of searching the clothes bag for the pillow case all of that bedding goes into and comes out of one bag

 

[sailsman63]

@Mike McCrea

Did anyone else look at this stuff and go "Custom float bags/Ballast bags?"