The C-Brats Forum Index
HomeForumsMy TopicsCalendarEvent SignupsMemberlistOur C-DorysThe Brat MapPhotos

Inflatable Kayaks Dropstitch

 
Post new topic   Reply to topic    The C-Brats Forum Index -> General Technical Discussions
View previous topic :: View next topic  
Author Message
colbysmith



Joined: 02 Oct 2011
Posts: 3888
City/Region: Madison
State or Province: WI
C-Dory Year: 2009
C-Dory Model: 25 Cruiser
Vessel Name: C-Traveler
Photos: C-Traveler and Midnight-Flyer
PostPosted: Fri Jul 08, 2022 2:20 pm    Post subject: Inflatable Kayaks Dropstitch Reply with quote

My inflatable Hobie has developed a bubble, and I'm not sure why. I have also discussed this some on the Hobie forum, and one response said it may have something to do with the drop stitch. Not sure I understand exactly how it all works, but trying to figure out if the bubble is an issue that a air leak could form from, or if it's just cosmetic. Anyone more educated about this? Colby



Back to top
View user's profile Send private message Send e-mail Visit poster's website
thataway



Joined: 02 Nov 2003
Posts: 19934
City/Region: Pensacola
State or Province: FL
C-Dory Year: 2007
C-Dory Model: 25 Cruiser
Vessel Name: thataway
Photos: Thataway
PostPosted: Fri Jul 08, 2022 9:35 pm    Post subject: Reply with quote

the inflatable floor (high pressure) drop stitch, is hundreds of strings which tie the top and bottom surfaces (re-inforced) of the hull or floor. If these threads break, there will be a bulge. Not sure that is what you have. I know that Hobie can recondition their boats. I sent my single sit inside back for repair under warrantee.

I would call/email the Hobie factory and see what they say-

worry is what is going on underneath.

_________________
Bob Austin
Thataway
Thataway (Ex Seaweed) 2007 25 C Dory May 2018 to Oct. 2021
Thisaway 2006 22' CDory November 2011 to May 2018
Caracal 18 140 Suzuki 2007 to present
Thataway TomCat 255 150 Suzukis June 2006 thru August 2011
C Pelican; 1992, 22 Cruiser, 2002 thru 2006
Frequent Sea; 2003 C D 25, 2007 thru 2009
KA6PKB
Home port: Pensacola FL
Back to top
View user's profile Send private message Send e-mail
colbysmith



Joined: 02 Oct 2011
Posts: 3888
City/Region: Madison
State or Province: WI
C-Dory Year: 2009
C-Dory Model: 25 Cruiser
Vessel Name: C-Traveler
Photos: C-Traveler and Midnight-Flyer
PostPosted: Fri Jul 08, 2022 10:09 pm    Post subject: Reply with quote

Hi Bob. I did email Hobie, but really didn't get much of a reply.

Quote:
Thanks for reaching out to Hobie regarding your Mirage i11s. From what I can determine, the air bubble looks cosmetic and may not impact the structural integrity of the boat. I am unsure how this occurred, although we would recommend to ensure you're storing your i11 out of the sun, heat, humidity and at least partially deflated. Hobie offers a self repair step-by-step guide for Hobie Inflatables, and here is the step-by-step guide below, as well as the recommended materials for this process. Here is a link to the video outlining a patch process in case it is helpful: https://www.youtube.com/watch?v=vmjdyhu_sVc


The youtube video has nothing to do with repairing this bubble, but rather how to patch a leak...

I have gotten a little bit more information from the Hobie forum, but not much. It is well out of warranty now, and they no longer manufacture this model. I'm still doing some research but at this point don't think the bubble is growing. Colby
Back to top
View user's profile Send private message Send e-mail Visit poster's website
colbysmith



Joined: 02 Oct 2011
Posts: 3888
City/Region: Madison
State or Province: WI
C-Dory Year: 2009
C-Dory Model: 25 Cruiser
Vessel Name: C-Traveler
Photos: C-Traveler and Midnight-Flyer
PostPosted: Mon Jul 25, 2022 9:35 pm    Post subject: Reply with quote

Did a little more researching, and closer inspection of my kayak today. I don't believe there is anything wrong with the drop stitch, as the bubble is only on the top. No bubble on the bottom. Also, I can press down on the bubble and feel more solid material under it. When I inflate the kayak, the bubble forms relatively slowly compared to the rest of the kayak inflation. Also, when I press down on the area, it sounds and feels like some tackiness between the bubble and the material beneath it. Somewhat like delamination where the inner and outer material was glued together. Not sure if I need to try to repair anything, or just leave it alone. I did mark the outer diameter of the bubble with a marker, so I can watch to see if it grows anymore.
Back to top
View user's profile Send private message Send e-mail Visit poster's website
thataway



Joined: 02 Nov 2003
Posts: 19934
City/Region: Pensacola
State or Province: FL
C-Dory Year: 2007
C-Dory Model: 25 Cruiser
Vessel Name: thataway
Photos: Thataway
PostPosted: Tue Jul 26, 2022 9:55 am    Post subject: Reply with quote

This may be a little extreme, but you can put some HH66 glue with a syringe into the bubble, then press it down--you will probably have to put a small patch over the entrance of the needle or hollow structure you use to convey the glue.

The other option is to send the boat back to Hobie and get it repaired. I did that with my. sit in 9' Hobie and they basically with thru the boat, fixed and upgraded it. (IF anyone is interested in a 9' sit in--it has only been used a few times and I need to "move it". Really good deal for someone.
Back to top
View user's profile Send private message Send e-mail
colbysmith



Joined: 02 Oct 2011
Posts: 3888
City/Region: Madison
State or Province: WI
C-Dory Year: 2009
C-Dory Model: 25 Cruiser
Vessel Name: C-Traveler
Photos: C-Traveler and Midnight-Flyer
PostPosted: Tue Jul 26, 2022 9:56 pm    Post subject: Reply with quote

Quote:
This may be a little extreme, but you can put some HH66 glue with a syringe into the bubble, then press it down--you will probably have to put a small patch over the entrance of the needle or hollow structure you use to convey the glue.

The other option is to send the boat back to Hobie and get it repaired. I did that with my. sit in 9' Hobie and they basically with thru the boat, fixed and upgraded it. (IF anyone is interested in a 9' sit in--it has only been used a few times and I need to "move it". Really good deal for someone.


Thanks for the suggestion Bob. The syringe and HH66 might be worth doing. I just wonder if it would work with whatever is currently in there that feels tacky. I have written Hobie again with pretty much the same information as what I wrote above. So far I'm not over impressed with their customer service. To often they more or less refer me back to the seller. (Maybe I should call the marine shop that I purchased it from, but I don't think Kayaks are their primary business. They just happened to have a few on the side, but I don't think they service or are knowledgable about them. Maybe I'm wrong.) Perhaps tomorrow I'll try calling the dealer, and if no help there, I'll try calling Hobie. Email doesn't seem to work well with them. Colby
Back to top
View user's profile Send private message Send e-mail Visit poster's website
colbysmith



Joined: 02 Oct 2011
Posts: 3888
City/Region: Madison
State or Province: WI
C-Dory Year: 2009
C-Dory Model: 25 Cruiser
Vessel Name: C-Traveler
Photos: C-Traveler and Midnight-Flyer
PostPosted: Wed Aug 03, 2022 9:29 pm    Post subject: Reply with quote

Some followup on my Inflatable Kayak issue. Someone else just posted a similar situation on the Hobie Forum. See this link for more information:

https://www.hobie.com/forums/viewtopic.php?f=47&t=70136&p=334088#p334088

From that link you can follow it to my original link.

Colby
Back to top
View user's profile Send private message Send e-mail Visit poster's website
thataway



Joined: 02 Nov 2003
Posts: 19934
City/Region: Pensacola
State or Province: FL
C-Dory Year: 2007
C-Dory Model: 25 Cruiser
Vessel Name: thataway
Photos: Thataway
PostPosted: Thu Aug 04, 2022 11:27 am    Post subject: Reply with quote

Interesting reply from Hobie tech. I'll bet they have seen this before. I am not surprised that this is the outer layer only. I don't know how the drop stitch are attached, but they may pass thru a layer, which is then attached to the "outside layer" My guess is this can spread--but you have it marked.

From their answer we can assume that you cannot leave the boat inflated in the sun--but that you have to let some pressure out if it is sunny or hot, after you use the boat, and then add pressure when you are ready to use it. If that is the case, then it makes the boat difficult to use as a dinghy.

Based on what they say--I would agree that it would be best to cut his open, fine the pinhole (?) and repair it--then you can spread the glue and put the top deck back on. You have to have some hard object to allow rolling the repair upper layer. HH66 is a contact type of cement, so if done properly you don't have to clamp it. I just used a wooden roller when I made the camper "canvas" enclosure for the back of the 25. Two part glues may be stronger, but when I did "destructive testing" the fabric pulled apart before the glue line failed. After you have sealed the bulged layer, you may want to put some PVC fabric over the incision.
Back to top
View user's profile Send private message Send e-mail
ssobol



Joined: 27 Oct 2012
Posts: 2945
City/Region: SW Michigan
State or Province: MI
C-Dory Year: 2008
C-Dory Model: 22 Cruiser
Vessel Name: SoBELLE
Photos: SoBelle
PostPosted: Thu Aug 04, 2022 3:19 pm    Post subject: Reply with quote

I have a Bote kayak. It has similar bubbles on the sides where a D-ring patch is attached to the surface. I really don't think anything of it.
Back to top
View user's profile Send private message
colbysmith



Joined: 02 Oct 2011
Posts: 3888
City/Region: Madison
State or Province: WI
C-Dory Year: 2009
C-Dory Model: 25 Cruiser
Vessel Name: C-Traveler
Photos: C-Traveler and Midnight-Flyer
PostPosted: Thu Aug 04, 2022 6:04 pm    Post subject: Reply with quote

I wasn't overly concerned with the bubble. Until I read the other persons post. My bubble is very close to the plastic rim where the peddle (Mirage) drive is placed. If that seam there was to let go, I would lose air pressure in the main body. Not what I'd want to happen while kayaking away from shore in deeper water! So at this point I'm a little leary about using the kayak in colder water away from shore. It'll be interesting to see what the next reply from my dealer or Hobie is. These Kayaks aren't cheap, and if Hobie isn't going to stand behind their product, you can bet I'll be honest with others about that fact, and will likely replace this Kayak with another Sea Eagle Kayak like my wife has. Or perhaps switch to more of a dinghy like the Kaboats. Colby
Back to top
View user's profile Send private message Send e-mail Visit poster's website
colbysmith



Joined: 02 Oct 2011
Posts: 3888
City/Region: Madison
State or Province: WI
C-Dory Year: 2009
C-Dory Model: 25 Cruiser
Vessel Name: C-Traveler
Photos: C-Traveler and Midnight-Flyer
PostPosted: Thu Aug 04, 2022 6:42 pm    Post subject: Reply with quote

Not really sure where to go with this reply, other than to say I guess Hobie feels 5 years is a normal life span for the I11S Mirage Kayak used recreationally... Colby

Inflatables are susceptible to heat and over-pressurization... and heat causes over-pressurization too. Inflatable products using glues are subject to glue degradation and failure from age and heat. This is an issue across the board with other companies. There are restrictions on better (but toxic) glues (EPA) I believe and this can limit the choices companies can use. Our product is unique in that we also have a well that the materials have to bond to. No mechanical connection should be required.

Unlike rotomolded and thermoformed products, inflatables can degrade just sitting in storage as the glue materials age and succumb to heat. 5 years depending on conditions and level of use is actually pretty good. I have been to the Caribbean and seen mountains of inflatables that have failed in use by charter companies.

Inflatables offer many advantages in weight, storage, and transport space required... but they do have limitations in lifespan. One of the reasons the warranty on inflatables is less than on other products.

We don't do repairs here at our facility, but there are companies that do in many areas of the country. I would contact those kinds of people (if your dealer is not able to help) for the best help in handling a repair.

_________________
Matt Miller
Director of Parts and Accessory Sales
Warranty and Technical Support
Hobie Cat USA
Back to top
View user's profile Send private message Send e-mail Visit poster's website
thataway



Joined: 02 Nov 2003
Posts: 19934
City/Region: Pensacola
State or Province: FL
C-Dory Year: 2007
C-Dory Model: 25 Cruiser
Vessel Name: thataway
Photos: Thataway
PostPosted: Thu Aug 04, 2022 8:40 pm    Post subject: Reply with quote

There have been inflatables which have lasted a long time. For example I had an Avon RIB and it was over 20 years old, and still in good serviceable condition when I sold it--no patches, no busted seams, but some fade in the outer Hypalon skin.

My son buys a 10' Costco dinghy every 6 years for running around Dana Point harbor. , and has an older Avon he uses for serious work.

The good Achilles also lasted many years.

When Zodiac started buying up other companies and went to PVC, there was a marked decline in longevity.
Back to top
View user's profile Send private message Send e-mail
thataway



Joined: 02 Nov 2003
Posts: 19934
City/Region: Pensacola
State or Province: FL
C-Dory Year: 2007
C-Dory Model: 25 Cruiser
Vessel Name: thataway
Photos: Thataway
PostPosted: Thu Aug 04, 2022 8:41 pm    Post subject: Reply with quote

There have been inflatables which have lasted a long time. For example I had an Avon RIB and it was over 20 years old, and still in good serviceable condition when I sold it--no patches, no busted seams, but some fade in the outer Hypalon skin.

My son buys a 10' Costco dinghy every 6 years for running around Dana Point harbor. , and has an older Avon he uses for serious work.

The good Achilles also lasted many years.

When Zodiac started buying up other companies and went to PVC, there was a marked decline in longevity.
Back to top
View user's profile Send private message Send e-mail
colbysmith



Joined: 02 Oct 2011
Posts: 3888
City/Region: Madison
State or Province: WI
C-Dory Year: 2009
C-Dory Model: 25 Cruiser
Vessel Name: C-Traveler
Photos: C-Traveler and Midnight-Flyer
PostPosted: Thu Aug 04, 2022 9:47 pm    Post subject: Reply with quote

I have to laugh at the continuing discussion on the Hobie Forum. The "Director of Parts and Accessory Sales
Warranty and Technical Support
Hobie Cat USA" last post says he was just giving his two cents, that he's not really an inflatable guy... Colby
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Display posts from previous:   
Post new topic   Reply to topic    The C-Brats Forum Index -> General Technical Discussions All times are GMT - 6 Hours
Page 1 of 1

 
     Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You cannot download files in this forum



Page generation time: 0.0676s (PHP: 82% - SQL: 18%) - SQL queries: 31 - GZIP disabled - Debug on