Glueing davits to an achilles inflatable????

So i got the davit kit, the rubber receptacles which are mounted on the inflatable.

I did the prep work as per the instructions, glued them on but only to find the adhesive didnt do the job, not sure where it went wrong but now i got to clean off all the adhesive from the back of the mounts and try again.

*

really hoping someone here has a few good tips on doing this properly...

I have patched a hypalon inflatable in the past using Defender's hypalon glue. I followed the instructions which I believe called for sanding the area to be glued.

The patches lasted years and were 100% intact when I donated the boat to my son 5 years ago and are still sound.

If it is hypalon fabric, it isa tricky process.* Everything has to be right.* I believe talulene is the solvent for tacking off and cleaning up.* Sanding, low humidity, and no direct sunlight.* I have glued on the pads for the Weaver snap davits.* They work well for light weight dinghys.

I tried to retrofit Weaver snap davits to my Tinker Tramp, which is hypalon. The Inflatable Boat Shop guy did it first - didn't last. I tried twice more myself with the correct two pack contact cement, sanding the area - all the right things - also didn't last. I think if put on properly from new they should be ok - a lot of people around me use them, but to an older inflatable, not so easy. Maybe part of the problem is the mushroom valves on my dinghy leak slowly over time, and the collapsing of the shape right at the weight-bearing glue site seems to cause it over time to come away as a result of the shape deformation. Later type dinghys seem to have better valves that leak less. Anyway, good luck with that. They are quite a good way of mounting a ducky on the swim platform, so worth a real good try. In the end I just left the part that is meant to be glued to the dinghy attached to the snap fittings on the duckboard ('swhat we call them), and use them as a buffer to swing the dinghy up against when we retrieve via a simple block and tackle arrangement clipped to the grab rope on the far side. I just loop the near side grab ropes, which are very stoutly fitted at three places along each side, over the hook part of the duck-board fitting, then pivot the dinghy up sideways and the pad that was meant to be glued to the ducky just protects the side of the dinghy from the metal hook-like projection as it then rests against it. Sounds complicated to describe - works well in practice and dead simple in practice, and no more gluing. However, if you don't have ropes along each side, you have no choice but to make the b**** glue work...

thanks guys, i did sand and then treat with some acetone but yes the sun was around.. and possible some humidity as well...
guess i get some talulene and a power sander to get the icky stuff off again and do over.

Peter i understand what you are saying, and thats not a bad idea either but i would prefer to get the buggers on the dinghy somewhat permanently...

I remember using acetone not toluene. Oh well, whatever I did worked.

Per
I have a Weaver Arc on the transom but have installed the front pad twice. The first round held a about a year before coming loose, the second time appears much better after about 2 years. The second time I designed a way to squeeze the pad onto the hypalon overnight after deflating the tube. Not easy to to.
Imagine two- 2 foot 2x4s. Now screw a 2x2 the width of the 2x4 onto the end of the boards. Now-at about 1.5' from the 2x2 you drill a 1/2" hole at the same spot on both boards. Pick up a one foot 1/2-13NC piece of all thread, 2 nuts and 2 fender washers. Install the all- thread through the holes and now you have a large "clamp". Hope this is clear. I could draw a picture and fax it if you want.

Steve,
Thank you, that makes sense. I have some ideas how to clamp it, and i believe you are correct that it need some sort of clamping during the curing process. I used tape as per the instructions but really didnt work all that well, the tube is slightly arched but the pads are flat, so there is a tendency for the edges to come off.
thanks for your input.
Per

I put Weavers on an Achilles, hypalon dinghy. I cleaned with Toluene, sanded lightly, used NEW GLUE. I sold the boat, kept the dinghy, so took the weavers off using a heat gun and sold the weavers. They were tough to get off after 4 or 5 years, wouldn't have come off at all without the heat gun.
the secret is to go and buy NEW GLUE from your dinghy shop. Don't buy it if the can looks like it has been on their shelf for a year, as it won't hold.
Did I mention, the most important thing is to use only NEW GLUE.

Did I mention the age of the glue is an important factor?

Well, if you want it to stick.......

Per:
Clamping isn't very important. You need to position the deflated tube so there is no tendency for the pad of the Weaver to try to pull off, while the glue cures. Otherwise, clamping shouldn't be necessary, just a little pressure.
If you find some NEW Glue, don't open it till you are going to use it. Throw it out when you have completed the job.
If you can't buy glue that is fresh, go to a different store.

I have tried old glue. Nothing has ever lasted for me using glue that was opened last week or earlier. It has to be fresh.

Carl:
Do you think that's enough?

koliver wrote:
Did I mention the age of the glue is an important factor?

Well, if you want it to stick.......

Per:
Clamping isn't very important. You need to position the deflated tube so there is no tendency for the pad of the Weaver to try to pull off, while the glue cures. Otherwise, clamping shouldn't be necessary, just a little pressure.
If you find some NEW Glue, don't open it till you are going to use it. Throw it out when you have completed the job.
If you can't buy glue that is fresh, go to a different store.

I have tried old glue. Nothing has ever lasted for me using glue that was opened last week or earlier. It has to be fresh.

Carl:
Do you think that's enough?

Click to expand...

Good info- but in my earlier post I may have forgotten to mention that I used NEW glue on my first application. I also was installing a NEW pad . I also marked the pad area, sanded per instructions and completed the job in OUR KITCHEN to make sure the humidity was low. All supplies were ordered through Triad Marine in Kemah. And STILL it started to lift at the edges in in a few months. On the second time I used new glue again, built and used the clamp, and installed the pad outside- here in good ole Louisiana. Much better result. I recommend a clamp AND new glue!!

Old Stone wrote:
Steve - Did you use NEW sandpaper ???????? I think Keith is trying to hoodwink us all !

Click to expand...

CRAP!!
That's where I went wrong!!

well, so far all i have done is tear off the half loose pads, cleaned up all the old glue from pad and tube.
now i am ready to try again..
i dont have a good place to actually do this job.. (cannot be in the sun and must have low humidity).
btw, the instructions that came with the pads indicate that you should NOT deflate the tube.
i found some strong guide lines on the web
http://www.shipstore.com/SS/HTML/INFO/INFOHYPNEO.HTML

I FIND THE BOTTOM COMMENT A LITTLE IN MY FACE...:
Believe us, we do not enjoy grinding off dried glue from a botched job. You won't either!


but i can totally agree, grinding the dried glue off is annoying work and not at all as easy as one could think.

My conclusion is to take the inflatable apart/deflate, take it home to the garage and do the job away from the water.

And how did that go in the end Per? I have been reading about the new Ring davit, (bought 3 Brit boating mags as something to read on a long plane flight back from UK, as had run out of books, there was an article on them - gosh 7 hours one leg and 14 the next is a drag), and it seems to me these might be a good solution to the inflatable tender on the transom board issue....? If I was setting up for a tender from scratch now, I think this is the way I'd go....
http://www.cooneymarine.co.uk/pages/tender-ring-davit.html

- gosh 7 hours one leg and 14 the next is a drag,

Think of doing it 3x a month for years on end!

A real butt-dragger , tho the pay is nice.

Peter B wrote:
And how did that go in the end Per? I have been reading about the new Ring davit, (bought 3 Brit boating mags as something to read on a long plane flight back from UK, as had run out of books, there was an article on them - gosh 7 hours one leg and 14 the next is a drag), and it seems to me these might be a good solution to the inflatable tender on the transom board issue....? If I was setting up for a tender from scratch now, I think this is the way I'd go....
http://www.cooneymarine.co.uk/pages/tender-ring-davit.html

Click to expand...

*you had to ask

i deflated the tender, took her home.

upon removing the other of the two pads, i guess the glue showed its strength and peeled some of the outer layer off from the achilles tube..

now consider taking it to a shop to get it done.

*

thanks for the link, it looks workable but for me, i'd rather prefer not to have those arches on my swimstep, to me they look dangerous (we actually use the swim step for enjoying a swim in the water).


-- Edited by Per on Monday 6th of June 2011 11:45:34 AM

update: the pads are on.. did the job at home, went 100% by the book.
right temp, right humidity, no direct sun.
sanded and prepped using a solvent containing MEK/Toulene, two thin layers of glue with curing time in between.
used gripwise x 4 to keep the pads firmly in place while curing for 48 hrs.

since i am now also redoing the varnish on the transom and the wood floor it will be a day or two before i get her inflated to see if them pads actually stick.
hopefully i got them in the right place also.

Well good luck with that. It sounds like you did everything right, so as they tend to stick when done by the shop from new, this oughta work. If it does not, then they never will stick properly, as you left no stone unturned, as they say, so there is always the other ring thing approach. I don't think they would interfere too much with swim step function.

We put her together and inflated the tubes on Fathers day morning. Even treated the tubes with a cleaning agent so her blue coat really shone as she went back in the wet.
Her new varnished floor, transom and bench seats were glistening.
The new bottom drain plug kept her dry on the inside.
When pulling her up to our swim deck, I put the brackets into the pads, clicked in the the one davit, holding my breath and much to my amaze they fit perfectly.. i was very stoked.

Per, if that NEW GLUE fails you, let me know. I just found some OLD GLUE sitting around from a couple years ago that you can have for free!!! ;-)

the glue will not fail, least i will never admit to it, should it happen...

I have a 9 achillies rib I came to me with the weaver pads glued on I managed to get hold of the remaining weaver parts to mount on my swin platform So my question is can I expect the glued on pads to hold a 9' hard bottom boat ot is it just a matter of time before they pull off? I believe that boat weighs around 150lb

I think the should if applied right - preferably from new. The secret to not over-stressing the glue join in my view, and which I was not able to ensure, is that the pontoons remain fairly tightly inflated, so the glued area is not subjected to sheering forces from under-inflation buckling the joined surfaces. Ie, keep them well pumped up - repair leaks immediately. My problem was slowly leaking valves from poor valve design.

In reading this thread there hasn't been much discussion on PVC material for the tubes.
I just purchased a 10' used PVC RIB and intend to place Weaver Snaps on it.
In checking with Weaver, while the pads that came are Hypalon the tubes are PVC the pads. They will work with the correct glue
There are two formula of glue. For PVC with a different solvent for cleaning and the glue for Hypalon and a different solvent.
So I will have to purchase the correct PVC blue and use Acetone as the cleaner.
Fine now for the second issue and inquiry to those who have installed the pads. In my case, with PVC, the seller of this model-'Endeavor' placed their signage in such a location that installing the pads at a distance apart and balanced on the tube, is impossible.

With PVC unlike Hypalon, heat can not be applied to remove the name plaque. Weaver representative allowed that one can sand down the edges to allow the Weaver pad to flow over the edge. Care with the sanding results must not allow a 'hump' allowing water to enter under the pad. Sounds challenging to be sanding near a surface that specifically speaks to NOT sanding PVC. Even that the offending signage is a rubber material. This begs the question, has any trimmed the pads to clear objects on the tube that were factory installed? With a bit of trimming around each end of the Weaver Pad would allow fitting the pad between said signage and the lifting handle mounted on each tube aft.

Al-Ketchikan

Okay Inflatable owners- so now we have to become serious:

I have not received any response from any source that I Googled and inquired: "Is it possible to remove manufactures/seller applied raised rubber type signage plaques off PVC inflatable tubes?" As one can not 'sand' the surface of PVC. the only option which seems a bit scary, is to grind off the emblem with a Drumal tool. Has any attempted to remove a raised rubber emblem? and if so how? and lastly, opinion on final surface that will suffice the glue application. If I sand, and grind to the outer limits felt to not attack the PVC your concept of 'Final' (aside of puncturing the PVC skin)

Al

Contact a respected and "old" dinghy repair company and talk to a real person.

bilge53 said:

Contact a respected and "old" dinghy repair company and talk to a real person.

Click to expand...

Sorry Bilge, I mis-spoke. In deed I spoke with the Weaver folks and they are the ones that suggested the 'sanding' off the naming plaques. At the same time, emphasizing that sanding the PVS material would result in a puncture. Hence my concern in asking if someone out here in the forum had access or knowledge of a better process. Your response was a correct one given my error in describing.

Regards,

Al-Ketchikan

Al, rather than a risky sanding, puncture, and repair as prep, could you apply Sikaflex or similar polyurethane over the offending brand plaque, and glue to that. Maybe the Sika would even work as the glue, an all in one job. I`m not sure what the contact type glue typically supplied for pvc repair patching consists of, but I successfully used a liquid polyurethane glue where a dinghy pvc panel came adrift from the transom outboard panel.

BruceK said:

Al, rather than a risky sanding, puncture, and repair as prep, could you apply Sikaflex or similar polyurethane over the offending brand plaque, and glue to that. Maybe the Sika would even work as the glue, an all in one job. I`m not sure what the contact type glue typically supplied for pvc repair patching consists of, but I successfully used a liquid polyurethane glue where a dinghy pvc panel came adrift from the transom outboard panel.

Click to expand...

Hi Bruce, Different thought! The naming rubber plaque is of raised lettering on a raised form. The border on the form is also raised. I hope this is clear enough a description. Think of a brass plaque and trust you will see what I mean. Your suggestion would have me physically filling in the plaque surface flush and then as the Weaver pad will extend beyond the border of this offending plaque, It would need to have that surface raised to the level of the rubber naming plaque. (This sounds confusing as I type but will see if I can explain better!)

To clarify the issue. Weaver company remarks that the pads should be placed at the further out point on the tubes to distributed the weight on pivot points.

Between the aft hand hold pad, and the naming plaque the space is too short to fit the Weaver pad between. To place the Weaver pad before the naming plaque would have the aft Weaver pad just short of mid-tube with the forward Weaver pad located too far forward in respect to distance (At the point of the front tube curving ) So to balance the pads the naming pad has to be removed or modified. (10' RIB)

As I consider these replies, the grinding of the naming plaque is becoming the option much as I dislike the end result if the surface after grinding should not be sufficient to allow the glued Weaver pad to secure sufficiently. Then what? If I can not remove the naming pad due to the constraints of not using heat, or a dissolving material to soften the material, how am I to remove a insecure pad that will not fasten sufficiently, yet fasten enough to not release intentional?

Should have held out for hypalon boat!
No guts, no glory I suppose.

Al-Ketchikan

Al-Ketchikan

Bilge/Bruce.

Sent the following to Weaver Company (It included Bruce and my give and take)

Greetings- First thank you for the several conversations I have had with your phone representatives. Very professional. She answered twice to those inquiries. However I remain with a quandary regarding the issue of placing the Weaver Pad in a correct installation location on my RIB (Endeavor) 10'
Below is a give and take on the Trawler Forum where a suggestion is made and my response.
I am looking for confirmation to what I am now believing is the single option.
I think I am asking for a professional thought on "What is an acceptable surface level" to accept the Weaver pad with glue.
Or better yet, a better venue to proceed.
Thanks,
Alk-Ketchikan