Rubstrake replacement, seeking tips and advice

bowfront26 · 28 April 2017, 22:55

I'm looking for tips on applying rubstrake and overall just working with Hypalon glue. I'm hoping to apply 3 strips of 3.5" rubstrake to my Avon SR 5.4. Currently the deluxe mode has an old single strip of rubstrake that is in need of replacement.

I will be purchasing the material (part #20200) from technorubber.com. Current price is $1.44/ft with a minimum of 120' order. I'll use Clifton Hypalon glue from NRS.com , $55 for 32 oz.

Considering this is not an airtight patch application, do I still need to apply 3 thin coats to material and boat? Should I thin with toluene?

After the necessary prep work, I'm planing on applying the strake (masking the border) with tape. The person I spoke to said when applying long strips of material with the glue you can use toluene to re activate the glue right before adhereing the pieces together.

Does that sound correct?

Any other tips for applying 14-15' strips of 3.5" wide strake?

I plan on using a hair dryer to remove the old strake and then using an abrasive flapper wheel dremel attachment to remove old glue.

Rogue Wave · 29 April 2017, 11:04

The glue we use is Bostik 2402 2 part and providing you glue matches it's specs you should be good. the thinners for the glue is Bostik m501 and that does indeed contain toluene. be careful with the Toulene as its bad for you.

your plan seems fine but be careful with the Dremmel as it can be bad for the boat the Toluene will help remove the old glue also. if you can get a or nylon brush attachment that's the best tool. RIB Tube Tools - Tilley Inflatables

When attaching the strake you need to pull it very firmly from the end so that the strake gets stretched on to the tubes. if you got a friend who is strong he's your man for the job.

jwalker · 29 April 2017, 14:09

Reactivating the adhesive isn't normally necessary for hypalon adhesive, the surfaces are brought together when the adhesive is touch dry and this period last for more than enough time to glue a side. When applying the strake try to press it on to the boat in a way which excludes the air so you don't get trapped air bubbles, then it need to be pressed very firmly to the boat - use a narrow roller to get the necessary pressure or use something like a plastic screwdriver handle and press the surface in a sliding manner.

Be sure the atmosphere is dry and not a sultry type of day, and definitely don't do it over grass or damp ground, any moisture present will prevent proper adhesion - it will feel fine initially but it will fail at a later date.

bowfront26 · 29 April 2017, 14:29

Thank you. Yes I will be doing this with a friends help and will be sure to do so on a low humidity day (under 50%). My tubes hold air so I'm assuming to do this with the tubes inflated to normal pressure. My boat is older (1987) so the idea of flattening and applying pressure seems like it would possibly damage a seam or internal baffel but perhaps I'm being to cautious?

My initial thought was to use some tie down ratchet straps around the boat (going over and under to the other side) to apply constant pressure while the glue cures. Maybe i will fabricate something to go over the new strake to distribute the pressure more evenly(scrap 1x4 wood pieces) . Any thoughts?

Regarding reactivating the glue, I thought that the layers of glue you apply need to still be tacky right before joining the materials? How long does the glue stay tacky... meaning how long is my workttime after the 3rd layer of glue is applied?

jwalker · 29 April 2017, 15:22

You don't need to arrange for constant pressure to be applied, the adhesive is contact adhesive and the surfaces should be brought together as soon as the adhesive feels dry to the touch. It will immediately attach firmly together, there is no second chance!, though if it really goes pear-shaped with your alignment you may be able to flush between the surfaces with solvent and get it to peel apart. It is best to get it right first time!

Yes, you're being too cautious, roll it down firmly.

It's possible there is confusion between your hypalon gluing and gluing PVC. When gluing PVC the adhesive can be brought together when tacky or allowed to touch dry then flushed with solvent just prior to bringing together. Does this sound similar to the advise you've been given?

Edit: I've just read the Clifton adhesive usage instructions and they are pretty much as our Bostic ones are. They suggest a knuckle test for assessing the drying of the adhesive where it is dry to the touch with just a hint of tack - that sounds about right to me.

Always use the accelerator, we refer to it a hardener so if you read stuff from over here you'll know what we are referring to.

Rogue Wave · 29 April 2017, 19:58

NICE WORK WJ Saved me some typing

bowfront26 · 29 April 2017, 20:39

Yes the person I spoke to said that the last layer of glue should be slightly tacky (similar to masking tape) before joining together.

I'm wondering what length of section I can apply at a time without the glue fully drying? I would plan on having a table or such next to the boat to hold the remaining strake all prepped and read to adhere together. Could I have the back of the rubstrake fully glued with all 3 layers and then also have the full section of the boat glued as well (maybe 2 layers). The. Working my way along, I would only need to apply the 3rd layer of glue to the boat, wait until just tacky and join together and repeat until done?

jelwood · 29 April 2017, 23:43

Really you'd want the strake sanded, and 2 coats of glue a day or 2 before so that it's completely dry.

Then once you've prepped the boat roll it out round the boat, glue the tubes and then strake and get sticking, you can usually get away with sticking it a bit wetter than a normal patch.

Boat that size shouldn't take long at all to apply the whole thing, then once it's on give it a good roll.

Give it a bit of a stretch but don't go too mad cus it will get slimmer and you'll be left with over sanding

bowfront26 · 30 April 2017, 04:02

Good tips. The material is EPDM rubber so from what I've read I would be using Stabond instead of Clifton to adhere the rubber to Hypalon.

ncp · 04 May 2017, 03:27

Quote:

Originally Posted by jelwood

Really you'd want the strake sanded

This was my $0.02 - rough sand the strake and then wipe it clean to the side you're going to glue. Make sure it's not shiny anymore!

I used their dark grey - their light grey is closer to the stock Avon colour. It's a hair less in width that the real stuff you can buy from the UK, but the price is MUCH cheaper.