BCD I/D Repair

[omron]

Here is the prototype repair kit I am assembling for BCD Repair.

The Kit will have: Internal Flange / Rubber Seal / Outer Washer
Photo #1 shows all of the parts.
Photo #2 shows threaded internal flange (these were made to repair SQ BCD) 2-1/4" Hole.
Photo #3 shows a cap cover (original black, made white).
Photo #4 shows an assembled kit using just a cap cover.
Photo #5 shows an assembled kit using I/D Connector
Photo#6 shows the order of assembly.

---------- Post added October 20th, 2014 at 10:05 AM ----------

I am in the process of making my own repair kit for 4 SQ BCD's that are in excellent condition but all of the Inflator and Dump Valve internal flanges deteriorated.
My kit will be the Internal Flange with a Threaded Boss to connect the Inflator / Dump Assembly with an Outer Sealing Ring that the Inflator /Dump Assembly will compress onto the BCD fabric and the Internal Flange to make a complete seal that does not require any adhesives.
I eventually want to adhere the Internal Flange to the BCD, but I have yet to obtain an adhesive that I feel would be the proper combination for the material I am using.

---------- Post added October 18th, 2014 at 11:25 PM ----------

The best way to remove the still attached pieces of the old internal flange is to heat the area with a hair dryer set on high (you can heat it from the outside).
While still hot to very warm use a small plastic tool as the ones that come with 2 part epoxy for mixing, or a popsicle stick to scrap off the remnants of the old flange.
Then with a small piece of medium to fine grit sandpaper give it a little scouring to help with the adhesion of your bonding agent.

 

[omron]

Update to repair; These are the 4 SQ BCD's I have repaired.



Photo #1 / SQ-Predator - As you can see the BCD is in excellent condition and fully inflated / I personally used this BCD approx. 50 times.
Photo #2 / SQ-Predator - Repaired both I/D Ports.
Photo #3 / SQ-Predator - I/D Port.
Photo #4 / SQ-Predator - D Port using Cap only.
Photo #5 / SQ-Pro - Again BCD is in excellent condition Fully Inflated / When I was OWSI, I personally used this BCD during OW Training Dives, Approx. ???
Photo #6 / SQ-Pro - This BCD only has 1 I/D Port.
Photo #7-8 / SQ-Basic?(forgot name) BCD - There are 2 of this style BCD / Again in excellent condition as the tags are still like new.
These 2 BCDs were used by students.
Photo #9-10 / SQ-Basic Fully Inflated with 2 Ports repaired.
Photo #11 / SQ-Basic - I removed the Repair Kit from this BCD so we could inspect the interior condition of the BCD.
Photos #12-13-14 / SQ-Basic - Internal inspection shows that the polyurethane coating is still in excellent condition,
therefore I feel the interior structure integrity of the BCD is not compromised.
Therefore I have no qualms about repairing these BCDs.
Photos #15-16-17 / Show the original parts (OP), on some of the flanges, just the internal flange cracked, on others the threads separated from the unit.
So, instead of waiting for all of the flanges to self destruct, I removed them all from these 4 BCDs and made the Repair Kits.
IMHO / I feel that the OPs were made of inferior material or maybe over heated during the lamination process?

Yes, these BCDs are over 10 years old, but with proper care, maintenance and storage they will be around for another decade.

 

[spoolin01]

Great solution to a problem that plagues owners of those older BCs! Where did you get the inner flange? Fabricated? That's the impossible part to find. Some of the older BCs have a removable inner/outer port system with a large flange, but the inner flange is still a little on the small side for the SeaQuest BC.

Have you tried any urethane adhesives for this application?

 

[cruiser352]

We just had two ScubaPro BCDs fail, in the same way, on the same dive. I'm not getting any satisfaction from ScubaPro or from the dive shop. Your solution is perfect, how do I get two for my BCs?

 

[omron]

@spoolin01, Because I stay in a very rural area, after I documented and drafted a drawing I took it to a local man who has a small but sufficiently equipped machine shop in his garage and we made them ourselves.

At this time I have been unable to secure a urethane adhesive to try, my next trip to Singapore I will try to get some.
A lot of companies will not ship to Indonesia? I do not know if it is because of the hassle of paperwork or because of the flammable materials rules?
These parts were made of delrin (because it was all we had), which is hard to adhere to any type of material, so I had to really rough up the mating surfaces using a course file to get it to adhere. If we make them again, I am going to use a different material and different assembly procedure where the outer support flange threads onto the internal flange, like the Scuba Fix Product does.
The flanges are 2.9 OD, and I used a product named ThreeBond 1104, which is a elastomer that drys to a rubber consistency for my adhesive.
The BCDs I repaired have been pressure tested and leak tested and to this date have not failed.
I even left them in water for 24 hrs to make sure the adhesive would not fail.

---------- Post added November 4th, 2014 at 11:15 AM ----------

@cruiser352, Have you checked out the Scuba-Fix.com site?

Not that I would not like to help you, but I know SP BCD has a smaller hole (1.5 OD) if I am not mistaken. I do own a SP BCD also, but it has yet to fail.
Therefore I have yet to design a replacement for SP BCDs as of his time.
Unfortunately, BCD companies would rather you buy a new BCD rather than repair one that you could use for another decade.
I can understand their reasoning to a point, but as all BCDs have a tag that says that "This is not a Life Support Device", meaning that it is not regulated by the government to be used for Life Saving situations.
In reality, it is no more than an inner tube used to compensate your buoyancy while diving.
I to often see divers over-inflate their BCDs while on the surface using it like a raft, this also stresses the strength of the seal of the flanges.

---------- Post added November 4th, 2014 at 12:27 PM ----------

@cruiser352, also you can search this site: https://www.divegearexpress.com/bcs/bcdparts.shtml.
Someone else mentioned this site, I emailed them, but they said their ports were only 1.5 OD, I think they are more inline with the wing BCs.
That is why I decided to make my own.

---------- Post added November 4th, 2014 at 01:46 PM ----------

@spoolin01, just reread one of your older post about having to add material to a hole in BCD, I would think the best material to use for that job would be the iron-on denim patches that mom used to iron onto your jeans. If my recollection is right the patches have the same type of adhesive that you see inside the BCDs, therefore making it an ideal adhesion compatible material and you could use an iron to adhere them.
Also, if I had a BCD that had a small leak I think I would try to use a piece of the iron-on patch to repair it, granted I could insert the patch into the BCD and maneuver it into position of the affected area. Just a thought.
I also think the iron-on patches might be a good fix for torn wet-suits, personally I have never had to repair a wet-suit.

 

[omron]

@cruiser352, This is the email I received from Dive Gear Express regarding the flanges they sell.
If you right click on the inserted jpeg and open in new tab you can read it, I have been trying to convert it to text but was unable to.

 

[omron]

@spoolin01,
Didn't you mention in one of your post that you bought one of the Scuba-Fix Repair Kits?
I was wondering what size their flange is?
I finally came across the video that someone uploaded to You-Tube from the Scuba-Fix Kit, I found it interesting.

 

[spoolin01]

@spoolin01,
Didn't you mention in one of your post that you bought one of the Scuba-Fix Repair Kits?
I was wondering what size their flange is?
I finally came across the video that someone uploaded to You-Tube from the Scuba-Fix Kit, I found it interesting.

I didn't buy the Scuba-Fix product, it is just too expensive for what I'm repairing. I did buy an older junk SQ BC, that has the screw-together 'large' port. I've only done a quick try-fit with it against the BC with the crumbled port, but there's not going to be a lot of overlap with the inner flange from how it looked. The hole in the fabric for those BCs where they glued/welded the port in place was apparently larger than those with the screwed-together ports.

I've got some vinyl and hypalon patch materials from inflatable boat repair that I'll probably make a gasket out of. I think urethane or quality rubber cement should work well to mate the fabrics, and with smooth rubber material to face against, it shouldn't be necessary to glue the flange to the material since the port can be screwed tightly together. Lol, I tried fixing a favorite t-shirt with one of those iron-on patches and the glue sucked. I remember the patches mom used to use - they don't make 'em like they used to, I think. If you can find a good air-tight patching material of almost any construction, I think you can patch a bladder from the inside pretty readily - it's the nylon outer fabric that is tough to adhere to.

I didn't catch that your parts weren't threaded. I'd think delrin is excellent stuff for the port, so if you can machine a screw-together port so you don't have to glue it in place, you solve that problem. If you can identify an adhesive you'd like to try, maybe I can help get it to you. I looked up that Threebond 1104, it looks like good stuff. It's liquid hypalon! I'm going to have to try it out. I just did some quick internet research and it looks like 1104 has lead in it, so now there's lead-free 1194 that's more readily available but otherwise supposedly the same product.

 

[omron]

@spoolin01,
The kit we fabricated worked good with out the adhesive, I just want to make it simpler if some one decides to open the ports.
The Threebond 1104 is some good stuff, I pity the guy who has to remove these flanges, but I seriously do not think that will ever be necessary again.
Yes, delrin is a good material, that why they make motor gears out of it. I already researched a family member of delrin which has a better adhesion property, but I put the darn file somewhere were I can't find it again.

The reason I didn't thread the outer flange was because I wanted to try it out before I made the other 6 kits, but I went home that day and the man who was helping me, helped me too much and made all the flanges and outer rings that night, so I didn't want to inconvenience him by making the parts over.

The only Problem with delrin is it is a little flexible under pressure apposed to the standard PVC replacement parts.
Because when I used compressor to fill the BCD until the over-pressure vales opened, I could see the BCD material was wanting to stretch because my flanges are flat faced compared to the convexed original inner flanges.

Also the holes in SQ BCDs are way to large, so therefore your main pressure point is only going to be about 1/16" to 1/8' past the threads on the locking collar, that is why if you do not glue it you must use rubber seal on inner and outer surfaces for gripping force.
I thought about making a flange with a groove in it to pinch the fabric with a matching boss outer flange.

---------- Post added November 7th, 2014 at 10:35 PM ----------

@spoolin01,
I talked to the man who was helping me and he would be happy to make these flanges, I would just have to figure out the best way to ship them from Indonesia.
The last time I sent out some paperwork from here, approx. 32 oz package thru DHL is was $35.00.

 

[omron]

@spoolin01,
The other day while I was waiting for the glue to dry I serviced 2 old SQ Air Sources and found the diaphragm covers were scrapped so I went and bought 2 poppets that are used for securing interior panels in cars and made my own covers out of plastic bottle with the poppet inserted in the center for the purge button.LOL