The good news is that the shelter is probably salvageable. However, since you're asking advice on how to do it. It's a pretty good bet you're not capable of doing a permanent repair. As Roger suggested send the shelter back to its maker. No one should be in the business of making and selling CF shelters until they've made a number for themselves and used them in some pretty harsh conditions. It takes a lot of time, money and failures to overcome the inherent issues with Cuben Fiber.

Hopefully you'll get your money back and the designer can use it to experiment on new manufacturing techniques before trying to sell any more.

This is Judy from LightHeart Gear (under my husbands log in) - Yes, the tent is repairable, the tie out webbing probably needs to be removed first, and patches glued over the ripped area, the webbing needs to be re-sewn with some sort of support -
use regular contact cement, tape off the areas you plan to patch, smear some contact cement on the area and on the patch, wait for them to dry, stick together and roll over it with a wallpaper roller - use pressure. then put the webbing back, put a piece of grosgrain ribbon or something similar on the back side of the tent and sew back in place. Then put some cuben tape over the needle holes. - someone mentioned 'clamping it' - I have no idea what this is, just get a good roller and roll over it after putting the 2 parts together. I have a wide rubber roller (from scrap booking section of craft stores) and a hard plastic wallpaper roller that I use. If I can glue a seam - that's all I do, if it has to be sewn, and most of my tents do have to be sewn, then they get sewn. Areas that are under very high stress get heavier cordura nylon patches to support the seams.

I sew cuben all the time (wish I didn't) but any seam that gets any stress will have to be taped, especially if it's cuben to cuben. generally if I sew cuben to mesh or zippers it doesn't always get reinforced, but sometimes it does. This is why I hate working iwth cuben, it is VERY labor intensive. Sew a seam, tape it, cut a pice, glue a patch on it before sewing... it takes twice as long to make a cuben tent as it does to make a silnylon one. I know I've been threatening for a long time to quit working with cuben, but somehow, my stock just keeps getting replenished, and I keep getting orders. Some day...

Along the ridge line, I would probably just tape it to reinforce the area, it may need a patch glued on , but probably not. One of the reasons it's pulling apart is that it's not a lapped seam - this was a plain seam sewn on a single needle machine and then folded over - so the one side wehre it is pulling apart does not have the reinforcement that the other side of the seam has. Occasionally this type of seam is needed, but a true lapped seam is much stronger. - it requires a sewing machine that has 2 needles, 2 bobbins and special folders.

I'm curious, if this is the outside of the tent, how is it seam seled? This is why I have never been an advocate of using silnet as some have on cuben, the holes do stretch, and silnet does not bond with cuben. I tape all outside seams to seam seal and reinforce.

Also, since this is brand new - return it!

Edited by MarcPen on 12/12/2012 19:42:22 MST.

Yeah, I agree with most that Marc had to say. The upper seam still needs reinforcing, somehow. A full lapped seam would have been better...

The apparent stress on the seams cannot be from a light breeze. The loops, pole pocket and ridge line are all damaged. Remember that the spectra fibers are stronger than the plastic. So where thay have anchored behind some stitiching, they will stress the fulm for several inches away from the joint.

Anyway, unless you are very interested in saving 1-2 ounces, all the patches, glue and reinforcements also cost weight. The extra material you will need will cost money. The time spent (perhaps a day or two of solid effort) to get the thing straightened out would be better spent in simply making one yourself... I know you decided to return it. Good decision. I do not think you would be saving any weight over a silnylon version by the time you tried to repair it.

For Cuben fiber, it is extremely strong as long as there are no punctures. The minute there is a puncture, it loses it's strength almost completely and will tear from that point in a straight line outward somewhere. To fix that, you would have to remove the stitching, cut away any dammaged material, then re-sew taping the areas that are being sewn so the holes caused by the stitching are not stressed in a way where they would pull apart.

The fact that the manufacturer of your product was not aware of this would lead me to believe that any other craftmanship done on the unit could also be compromised in a way that could cause a catastrophic failure while in the mountains which given the weather scenario you are in could be a very bad situation.

"I will send the shelter back, I want one of those MLD DuoMid"s."

Definitely the best plan...I wouldn't even mess with taping/stitching, etc. as this will just add weight, look horrible, and the tent will just fail somewhere else anyway by the looks of the construction!

Contact cement and strips of cuben over the seam, probably both sides. Will take a lot of fiddling. That part of the repair will
be a pain.

Tape would work, but would be harder to get and
more expensive.

On the tie outs, A much larger glued reinforcement patch of cuben inside and out, then restitch the web back on. Don't
over do the amount of stitching. The stitching shouldn't be a box x. That's for parachute harnesses with force in multiple directions.

Silicone caulk won't hold.

The forces on that shelter were pretty high.

These photos show cuben fiber .51 oz versus silnylon 1.4 oz. All failed at the same time, the thread(7 lbs per stitch), the cuben and the silnylon at 42 pounds. Nylon stretches to reduce force over a large area, but when the force is concentrated, the .74 oz
cuben should be stronger than the 30d silnylon even stitched without other methods of reinforcement.

Edited by oware on 12/14/2012 09:47:28 MST.

Hi, Maker has offered a refund without me asking, which is great.

As soon I recieve refund, I will be ordering a Cuben MLD DuoMid. If I had the money now I would order today.
9 week waiting period, Ouch. And further two weeks postage time. Thats going to hurt, as I was planing to use shelter this coming Febraury at Tasmania.

Thanks to everyone that have offered advice, very much appreciated. Its been a distressing couple of sleepless days, upon word of refund, the relief was instant, I had a good nights sleep last night.

When you order the Duomid, Call MLD and talk to Ron about when you need it. I'm sure he'll try to get it to you in time.

One thing to think about with the Duomid in cuben is whether you want the "normal" cording and Lineloks (very easy to use), or go with the thinner and lighter cord, and perhaps the MiniLoks. The Lineloks are more versatile, but do add a couple of ounces. I use the smaller cords and no MiniLoks - just tying a slippery half hitch. No failures so far.

Spoke to Ron yesterday via email. He strictly sticks to orders as recieved. No chance for a quicker build.

I even offered to pay more. Not to worry, I will just have to wait, I think it will be worth the wait.

Edited by Phillipsart on 12/14/2012 20:30:12 MST.

It'll definitely be worth the wait. High quality shelter that will last many years with care

Edited by Empacitator on 12/15/2012 00:01:25 MST.

I have received a full refund on the shelter and ordered a MLD Cuben DuoMid.

I decided to go for a Oookworks Custom Inner for my DuoMid, but sean from Oookworks has not responded to any of my email's I've sent for the past two weeks. I am not sure what to do in regards to a inner for my DuoMid.

Really want one of those Oookworks, but there's no response from them for two weeks, which is a concern.

Edited by Phillipsart on 12/30/2012 18:51:12 MST.

Phillip,
Wondering why you did not order the inner that MLD makes for its shelter.
If you order the Oooworks, suggest you not order the Chikara nylon floor.
I ordered some Chikara 42 gm from Europe and found that altough it looks bombproof, it is actually not very water resistant, a big consideration for a floor.
Best of luck.

Hi Samuel, Thanks for the tip, yes I was going to order the Oookworks inner with a Chikara floor, but if it's not totally waterproof, that's not good, very important I have a waterproof floor. maybe will order with a nylon floor or better yet, cuben floor. I could ask them, but they don't reply to emails and the cost of adding a Cuben floor might be to high for me.

I've put off ordering the DuoMid till today, for the reason of the inner, I been tossing and turning weather to get the Oookworks or the MLD inner, decided today to go for the Oookworks for the higher walls, as I plan to mainly use this shelter in cooler climates and wondered if the full mesh of the MLD would be suitable for me. I now wonder if maybe I should have just ordered the MLD inner. To late now, I've ordered and paid for the DuoMid.

Oookworks looks like they make a fine inner with great features, I'm a sucker for features. I wouldn't mind the OookWorks Duomid hybrid inner he has linked to on his website that's 315 grams, but that's with a Chikara Floor. I wouldn't mind a quote for the inner with a Cuben Floor. But I sent an email out to them a couple weeks ago asking about this and thus far no response. The lack of communication with Oookworks is not good. I might have to look elsewhere. I might send Ron of MLD an email when he returns if maybe he could make some mods on his inner and add it to my order for the DuoMid.

Will give Oookworks a couple more days to respond if no response I will talk to Ron.

Edited by Phillipsart on 12/30/2012 20:21:42 MST.

Sean at Oookworks has recently moved house and has had problems getting broadband installed IIRC. You can search or ask at Outdoorsmagic to get more information.

Odd to hear about the Chikara leaking water. I also have a Oooknest with a Chikara floor and did not experience any leakage this summer. And Norway was plenty wet at times ;-) I normally pitch the nest without an additional groundcloth. Though on two days I used a polycryo sheet (fully covering the floor of the Duomid) because the ground was already saturated and it is much nicer when your knees and bum stay dry in the vestibule!

My only "regret", is that I bought a regular Oooknest instead of the nano; now that I used it for three weeks I think I would prefer a little more space in the vestibule at the expense of room in the inner.

Regarding Cuben, I believe it is not as abrasion resistant as nylon, so you need a thicker quality (Zpacks recommends at least 1.0 oz/sqyd for ground sheets) and that is more difficult to pack small because it is stiffer. No free lunches ;-)

I sent first email to Sean 3 weeks ago in regards to ordering a custom inner for my Cuben DuoMid and to date no replies.

I'm afraid, his missed out on a sale. Not waiting any longer.