Plexus

[Tater]

So, if I search "Plexus" on the Web, I get a multitude of products. Even a refined search including "ITW" produces multiple hits. I have only known the name for polishing plastic windshields.

What exactly do I need for cracks on a 170 and where do I get it?

 

[sail sfbay]

Please post photos of the cracks. Suggest contacting crazy dave condon about plexisus. These threads on repairing cracks in ACP might be helpful: hunter 170 acp cracks and delamination | Sailboat Owners Forums and Hunter 170 ACP repair | Sailboat Owners Forums.

 

[Tater]

Descriptions are easier. None are major. They are about 1.5' long and in the cockpit area. I have stop-drilled them. Thanks.

 

[Ralph Johnstone]

I have stop-drilled them.

So I take it you are talking about the hard acrylic ports and hatches and not the soft windscreen such as strataglass.

In two words, forget it. What you describe are internal cracks which are not coming out with surface treatments.

These fixed portlights are bright and shiny on the surface because they are polished with a Meguiars cleaner and polish. The internal cracks are growing by the year.

This Lewmar opening portlight below looks like new from the outside as it's frequently cleaned and polished. Inside, a different story when passing sunlight. Replaced all of the opening portlights' lenses in the boat last winter.

Time to replace them.

 

[chuckwayne]

Plexus is the adhesive used to repair cracks in the luran skinned boats - like the 170 and the 216. I use plexus Ma310, which bonds well with the luran (it's also used to build other boats). the cartridges it comes in are designed to use a special mixing gun - once it's mixed in the disposable nozzle, you have a 10-15 minute working time. once set, you can fill and sand the crack and use krylon spray paint to cover - the plexus isn't white...
you can buy it online - google it, and from Amazon

 

[Tater]

So I take it you are talking about the hard acrylic ports and hatches and not the soft windscreen such as strataglass.

In two words, forget it. What you describe are internal cracks which are not coming out with surface treatments.

View attachment 210021

These fixed portlights are bright and shiny on the surface because they are polished with a Meguiars cleaner and polish. The internal cracks are growing by the year.

This Lewmar opening portlight below looks like new from the outside as it's frequently cleaned and polished. Inside, a different story when passing sunlight. Replaced all of the opening portlights' lenses in the boat last winter.

View attachment 210022

Time to replace them.

This is what I have used, also called Plexus. It is great on motorcycle windshields.
Plexus Plastic Cleaner

 

[Ralph Johnstone]

It is great on motorcycle windshields.

Windshields are soft acrylic and maybe 0.060" thick. Your portlights and hatchlights are usually 1/4" thick.

Which are you dealing with ?

 

[ColumbiaRiverDoug]

Some years ago, I used Plexus together with inlaid fiberglass to repair the many cracks in the interior hull my Hunter 14. I purchased the product from RSHughs in Portland, Or. Crazy Dave Condon was a great help in getting me started with the project. Plexus is a methacrylate; about the only adhesive you can use on polystyrene. After several seasons, all the cracks that were fixed are still holding well. There are, however, new cracks that I'll deal with next spring!

Plexus MA330 Gray Two-Part Base & Accelerator (B/A) Methacrylate Adhesive, 400 ml Cartridge | RSHughes.com

 

[stickinthemud57]

The product is also available in 50 ml dual syringe packaging (MA310, stock #31500). It's shelf life after opening is not great (at least that has been my experience), so buying the larger one would definitely be more cost-effective than the smaller, though may not last until next use.

Also, I have found the working life to be less than five minutes, so using it with inlaid glass could get tricky.

Methyl Methacrylate is the key ingredient. Nasty stuff. Definitely work use in a well-ventilated area.