Tyvek Backpack
Display Avatars Sort By:
Kendall Clement
(socalpacker) - MLife

Locale: Southern California
Tyvek Backpack on 02/16/2009 00:32:17 MST Print View

Roger,

Would you use a polycotton or nylon thread with cuben fabric? I'm thinking of making a cuben fabric pack and experimenting with a cuben fabric tarp.

You guys (people in the MYOG forum) have really fired me up. Tomorrow I'm picking up a 35 year old "White" sewing machine I found on Craig's List. She says it works fine. It's just due to be serviced and she decided to get a newer machine... $10!!!

Also, does anyone have an opinion about primaloft (about 2") for quilt insulation?

Edited by socalpacker on 02/16/2009 11:54:16 MST.

Roger Caffin
(rcaffin) - BPL Staff - MLife

Locale: Wollemi & Kosciusko NPs, Europe
Re: Tyvek Backpack on 02/16/2009 13:19:47 MST Print View

Hi Kendall

I need to explain the difference between the two threads.

Nylon thread is usually pure nylon, is sometimes bonded, and is usually very strong. However, it can be a bit tricky to handle at times: it can kink up in my experience.

Polycotton (the good version anyhow) has a core of polyester fibres, surrounded by cotton fibres. The cotton lets the thread slide through the needle a bit easier, and when the needle gets warm (hot) during high speed sewing the cotton prevents the hot needle from partially melting the synthetic part of the thread. Yes, this can happen - with 100% polyester or nylon threads. Finally, when the cotton fibres get damp they can swell up a bit, blocking the needle hole.

For this reason one is usually better off using a polycotton thread for most sewing. I would normally only use 100% nylon thread for sewing webbing and heavy Cordura where that is going to be under load.

But don't think that polycotton is a whole lot weaker than nylon: it isn't. I use it for my tents quite happily - in quite a fine version.

What to use for Cuben? I have tested this fabric, and I would use a fine polycotton thread, but I would tape the seams afterwards to spread the load across the film rather than having it concentrated entirely on the sewing holes. A 'seam stick transfer tape' such as 3M9485PC is good.

Cheers

Kendall Clement
(socalpacker) - MLife

Locale: Southern California
Re: Re: Tyvek Backpack on 02/16/2009 13:32:48 MST Print View

Roger,

Thank you. That was extremely helpful.

Kendall

Jeremy Gustafson
(gustafsj) - MLife

Locale: Minneapolis
RE: Tyvek Backpack on 02/16/2009 14:11:20 MST Print View

Ralph,

Are all of your seams sewn or are some of them taped? How did you seal the seams that are sewn? It seams that sewing and Tyvek would not work real well together as it would make a perforation like a paper towel.

I'm thinking that one would need to use the sewing machine to make the nice pretty lines and corners and then reinforce the seams with a Tyvek type tape, which would also seal them as well.

I am thinking about making a tarp tent out of tyvek which is why I ask all the questions...

Great Project Ralph!! Inspiring!

Jeremy Gustafson
(gustafsj) - MLife

Locale: Minneapolis
RE: Tyvek Backpack on 02/16/2009 14:13:30 MST Print View

Roger, would that 3M tape work well for sealing Tyvek seams as well? Would it be strong enough to relieve stress on a sewn seam in the Tyvek?

Thanks!

D LARSON
(epilektric) - MLife

Locale: Midwest
Kevlar thread on 02/16/2009 15:51:56 MST Print View

Roger, thank you for your knowledgeable insight on Kevlar thread. You are a wealth of information.

Tim Marshall
(MarshLaw303) - MLife

Locale: Minnesota
Re: Tyvek Backpack on 02/16/2009 16:29:06 MST Print View

Kendall,

Primaloft can be used for quilts but it requires you to "quilt" it. It must be stabilized to the fabric throughout the large panels. Climashield on the other hand can just be edge stabilized (sewn to the fabric on the edges) making it a much simpler choice for MYOG quilters like myself. Also XP has highest CLO i know of making it warmer for the weight.

-Tim

Jim Colten
(jcolten) - M

Locale: MN
Re: Tyvek Backpack on 02/16/2009 17:37:33 MST Print View

Hey guys, we hooked another one! he-he

Kendall,

An emphatic ditto to what Tim said about XP being easier to work with for quilts. But I do like Primaloft for clothing, where you get quite a bit of quilting for "free" as part of the construction process.

Regarding a 2" thick synthetic quilt. Warm quilt! For PL or XP That'd offer an insulation value of about 6CLO ... which would keep me comfortable at about 10*F with little in the way of insulated clothing (nylon pants and shirt over a light poly base layer, warm socks) ... as always, YMMV

A single layer of 5oz XP would likely serve you down into the lower 30's ... well down into the 20's if you add lightly insulated clothing that you will likely want to also have along at those temps.

Jason Griffin
(JGriffinRN) - F
Tyvek Pack on 02/16/2009 17:43:02 MST Print View

Very nice job on that pack! Could you give some close up shots of your seams please?

Roger Caffin
(rcaffin) - BPL Staff - MLife

Locale: Wollemi & Kosciusko NPs, Europe
Re: RE: Tyvek Backpack on 02/16/2009 18:02:32 MST Print View

Hi Jeremy

> would that 3M tape work well for sealing Tyvek seams as well

3M9485PC is used and sold as a 'seam stick' transfer tape for making lightweight spinnakers for racing yachts. They do actually make some spinnakers with JUST the tape: no sewing at all. It makes a 'permanent' bond.

As an example, some may remember a light-weight Dimension Polyant fabric which had a bright orange layer of PU coating on one side. It was often called something like 'titanium' as it may have had some titanium oxide in the PU coating to make it UV-resistant. It was originally made for NASA as a fabric for (very) high altitude ballons. The coating was utterly waterproof, and quite thick and well-bonded. My first MYOG snow tent was made of this stuff.

I had some 3M9485 tape on a bit of this fabric for testing. After a few days, I tried to peel the tape off the coating. It wouldn't come off; instead it ripped the coating off the nylon cloth. That's a fairly strong bond!

Yes, it will bond to Tyvek, and yes, it should be good.

Cheers

Kendall Clement
(socalpacker) - MLife

Locale: Southern California
Tyvek Backpack on 02/16/2009 21:18:26 MST Print View

Tim & Jim

Thanks for the great advice. I wasn't thinking that I have cocoon wear as well. I just got back from picking up my sewing machine. I think I want to start with a quilt. Climashield XP sounds great. Now, I just have to find a pattern and instructions that I like and order the materials. So, I probably wont start for a couple of weeks. It'll give me time to familiarize myself with the machine. BTW the materials are surprisingly cheap compared to buying gear from a manufacturer! I was shocked at some of the prices I've seen! And, you don't have to compromise. You can make your gear just the way YOU want it. Of course, that's not news to you guys.

>Hey guys, we hooked another one! he-he

-LOL- Yeap! I think you got another convert. I'm looking forward to learning how to make my own.

Kendall

Edited by socalpacker on 02/16/2009 21:27:58 MST.

Ralph McNall
(rumps) - F

Locale: SF Bay
seams on 02/16/2009 23:57:11 MST Print View

Congrats on the sewing machine, Kendall.

So the seams for the tyvek backpack are a combination of thread and tape. The thread was polyester, I think I got the regular size from Gutermann at Joann Fabric, they also had a heavy duty. The pieces of tyvek that I had were on the smaller side so I often had to join 2 together to make a larger piece, and that was done with adhesive transfer tape like the stuff mentioned in earlier posts. I found it to be amazingly strong. I thought of making the whole pack with only taped seems, but I had a hard time picturing how it would all come together and have the shape that I wanted. I would still need thread to attach the mesh pockets and straps. Sewing tyvek is definitely different than most fabrics, and is really more like paper. Dupont recommends about 5 threads per inch and it works out pretty well, giving a fairly strong seam without tearing apart from the perforations. Never the less, I still went back and taped all my seams. Primarily it was to add strength, but also to waterproof it. The hardest part about sewing the tyvek for me was ending the seam. Usually you can back tack at the beginning and end of a line, but that doesn't really work, so I just relied on the tape to keep the thread from coming undone. I'll have to come up with a project where I can play around more with only taped seams. Perhaps a tyvek tent will be next...

Oh, and watch out for sewing through that tape - it will gunk up your needle and make a mess. I found I could use a little bit of wax on the needle if I had to get through a spot that I had already used it.

Edited by rumps on 02/17/2009 00:01:11 MST.

Roger Caffin
(rcaffin) - BPL Staff - MLife

Locale: Wollemi & Kosciusko NPs, Europe
Re: seams on 02/17/2009 01:56:58 MST Print View

Hi Ralph

> I found I could use a little bit of wax on the needle

Ah so! You are SO right about getting adhesive on the needle - a real mess. I had not thought about using wax, but I will try it out. I have tried light oil, but it is rather messy and does not last very long at all. Make marks on the fabric too.

Another problem is that the thread can get adhesive on it as well, and that also gums up in the eye of the needle.

Cheers

Rod Lawlor
(Rod_Lawlor) - MLife

Locale: Australia
Teflon lube on 02/17/2009 02:59:20 MST Print View

Roger,

You may also like to try a spray on Teflon lube on the needle. Oil and fabric scare me a bit. I always expect the oil to degrade the fabric rather quickly, although I'm not sure if this is true or not.

What's your stance on 100% polyester thread? I used some today to repair my Mid.

Dan Dyk
(leger) - F
ditty bags on 02/17/2009 03:36:44 MST Print View

Recycle Tyvek envelopes for ditty bags. Turn inside out so printing is inside. Closing flap can be cut off or used as bag flap or reinforcement of top. Roll a "cuff" about three or four thicknesses, crease each fold, maybe 1/2". Use paper punch to make holes around cuff, then thread a drawstring through holes. Or, two lengths of string, making loop of each after threading through holes. Pull loops and wrap and tie. Tyvek can be "softened" by crumpling into a ball several tiems. crushing and rolling in your hands. Tyvek bag will also serve to fetch water. Good as emergency mitts, over gloves. Or booties. Mukluks or gaiters can be made from Tyvek. Good for full face balaclava maybe with slit eyeholes, in bright snow. You can make slit goggles also. On and on. Tyvek footprint mat for your tent.

Jeremy Gustafson
(gustafsj) - MLife

Locale: Minneapolis
RE: Sewing Tyvek... on 02/17/2009 08:49:08 MST Print View

I am slowing becoming a convert as well. It was easy enough before to just buy my own gear as I got bonuses, but with the economy down, no more bonuses... so now I start making my own gear.

My wife is totally making fun of me and telling everyone that I am going to take up sewing. Funny thing is that just a couple years ago I told her that she should sell her sewing machine as she never used it and hated sewing. I guess it all comes back around...

I think I am going to start working with Tyvek just because I already have it... Not sure how easy it is to work with, but we will just have to see. I had crafted a Tyvek bivy last summer with a footbox, but an open top... Never got a chance to use it. I just used Tyvek Tape to make it, but sewing it will be a whole different story.

Being an engineer, I have drafted up a few different designs in AutoCAD. Don't normally draw in 3D, so there has been a bit of a learning curve there. But it is nice to get a visual of what I am creating before I start cutting up a bunch of fabric.

How does working with Tyvek compare with SilNylon or other Nylons? I will be working with the HouseWrap type. Would it be best to crumple it up and wash it before I sew it?

Joe Clement
(skinewmexico) - MLife

Locale: Southwest
Tyvek on 02/17/2009 09:14:38 MST Print View

I'm going to make a tyvek bivy some time myself. Need a good plan though......

Jeremy Gustafson
(gustafsj) - MLife

Locale: Minneapolis
RE: Tyvek Bivy on 02/17/2009 09:47:20 MST Print View

Joe,

I've been thinking about making another one as well and have found a couple plans that I would modify a bit.

Backpacking Lite out of the UK has a super simple bivy pattern.

Six Moons Designs also has a bivy pattern on their website as well. It has a mosquito net attached to it which I would remove and then extend the top up like a normal bivy. These shows how to make a footbox which would be nice.

I was thinking I would take from a little of both of these and draw up my own template. Since I am 6'-4", I would probably add a little bit to the length.

If I get a chance later, maybe I will draw one up in AutoCAD and post on here...

Kendall Clement
(socalpacker) - MLife

Locale: Southern California
Tyvek Backpack on 02/17/2009 09:55:45 MST Print View

Jeremy,

If you don't mind, I'd like to see your bivy plan when you're done. I looked at the Six Moon Designs bivy lasty night and had the same thoughts as you about the netting.

Kendall

Joe Clement
(skinewmexico) - MLife

Locale: Southwest
Tyvek Backpack on 02/17/2009 09:57:32 MST Print View

Some guys on here had a neat bivy plan, I'll have to go look for it.

To the OP....amazing backpack.