will epoxy stick to pvc pipe?

[dpincus]

I'm installing a centerboard lift line. Would like to use pvc pipe as the housing. Will epoxy stick to it?

[Ian McColgin]

Huh why what ????

Is this essentially just a little bushing through the top of a CB case or is this an installation in the cabin of a larger yacht meant to get the pendent up from the case and through the overhead to the deck?

I don't know why one would want a bushing given how many generations of boats do fine with a hole in the wood.

In a larger boat, the pendent's angle changes depending on how far up or down the board is and thus a pipe, being a straight cylinder, could not accomodate the change unless you also install a guide pulley in the trunk.

So, better explain if you want an answer.

Epoxy does not stick well to PVC but you can use epoxy to bed PVC in wood. One sees this in some prop shaft alleys, for example.

G'luck

[The Bigfella]

I thought I had a photo of some PVC tube that I strengthened with epoxy and fibreglass tape for use in the prop shaft hole on my boat, but I cant find it.

We used a piece of PVC conduit tubing and to get a good result, we put it in a lathe at slow speed, with a bit of metal inside it to hold it straight, spread out some newspaper to catch the drips and wound on some fibreglass tape at an angle. Then I painted it with epoxy and we walked away and let oit keep spinning until the epoxy went off. It came out damn well, if I say so myself. No problems with it sticking.

[RFNK]

If it's ordinary electrical conduit or plumbing pipe you're talking about then the answer is no, epoxy doesn't adhere to it very well. However, there's a type of plastic electrical conduit (in Australia it comes in white) that does adhere well to epoxy. Unfortunately I can't remember what it's called but if you call an electrical supplier they should be able to advise. Just tell them that you know there's a plastic conduit that will adhere to epoxy - what's it called, where can you get it? Rick

[boylesboats]

Sand the PVC well to roughen the surface, and clean with Acetone, make sure Acetone is dried throughly before applying epoxy..
Epoxy should be able bond to it mechanically..

[P.I. Stazzer-Newt]

There are glues specifically made for PVC pipe - try a plumbing supplier.

And different ones for ABS - be sure you know what you've got.

[Boatsmith]

Jim Smith Tournement Boats has been epoxying pvc for 26+ yrs. Its hard to say something doesn't work when your looking at results that were achieved in the early 80's. I spoke with John Vance of Jim Smith last a couple of years ago about this subject and he said they just scuff it and glue it.We bent some pvc tube around a flying bridge wall for use as a bolt rope track for the bottom of the enclosure. I also talked to J.R. Watson of West Systems. They have documented and quantified results of pvc epoxy bonds. From memory, just scuffing gave psi values in an acceptable IMOHO range. Interestingly they told me that by passing a torch over the surface of the pvc you will dramatically increased the bond strength. When the torch passes quickly over the pvc you can observe the gloss go away on the pvc, it happens very fast , well before any scorching. J.R. 's values indicated that this increased the bond strength to the point where the substrate let go before the bond. They will send these results to you if you ask. I for one epoxy pvc and haven't had any problems at all. PS this technique only works on sch40 , in tests in our shop we observed no visual change on sch80 and our peel tests showed no improvement over just scuffing. We can only find 3/8" tube in sch80 and have used this with no failures David www.boatsmithfl.com (http://www.boatsmithfl.com)

[Bill Perkins]

Thanks for the info Boatsmith ( an impressive website ).

[spirit]

Some of the newer and more flexible epoxies, like West's G/flex epoxy, are recommended for bonding to plastics (after some roughing and/or heating, plus an acetone wash). Circling a plastic object, even a bucket, can help too.

[dpincus]

This is for a plastic C&C Redline 25 I got for a buck a couple of weeks ago. "this [is] an installation in the cabin of a larger yacht meant to get the pendent up from the case and through the overhead to the deck".

The former pipe and lift line were removed in this boat by a previous owner and the hole in the hull epoxied over and the centerboard just left to dangle. I want back the ability to raise the centerboard. So I drilled through the epoxy and reopened the hole (making it an oval with beveled sides to allow for the changing angle of the lift line) and need to install a tube to contain the lift line.4" pvc or galvanized pipe makes the most sense to me. If I use pvc it will be easier to shape the ends of the pipe to fit.

Here's a link to the plan. You can see the old pipe just behind the ladder going up to a reel winch which is in the cockpit. My reel winch is gone so I'm thinking I'm going to just use a shoulder block and cam cleat.

http://www.cncphotoalbum.com/brochures/25redline/25redb1pg04.htm

dpincus

[Ian McColgin]

dpincus, I think a PVC pipe epoxied into the hole will be just fine. I don't know how heavy the board is - one hopes the comma in the description means that the ballast is lead AND a weighted glass board, not a lead-weighted glass board of 1800#. Still, it's likely to be heavy. Try a lift in the yard before you commit to no winch.

It does seem to me that a plain pendent and cam cleat would be nicer than a winch obstructing things, if you can lift it.

G'luck

[Dan McCosh]

I epoxied PVC plumbing pipe into a holding tank about 20 years ago, and it is still holding up fine.

[JimConlin]

I've done OK bonding to PVC pipe using epoxy. Coarse sanding and flame treating are a good idea. Gougeons' G/Flex might be, too. However good a bond you get to the PVC, bear in mind that's not at all a stiff material and won't support much of a load, except in compression. I'd think about the load to be placed on the pipe and consider whether a tube of another material such as G10, shop-made glass, stainless or bronze might be better.

US Plastics (www.usplastic.com/) has Sched 80 PVC in a variety of sizes.

[boylesboats]

I've done OK bonding to PVC pipe using epoxy. Coarse sanding and flame treating are a good idea. Gougeons' G/Flex might be, too. However good a bond you get to the PVC, bear in mind that's not at all a stiff material and won't support much of a load, except in compression. I'd think about the load to be placed on the pipe and consider whether a tube of another material such as G10, shop-made glass, stainless or bronze might be better.

US Plastics (www.usplastic.com/) has Sched 80 PVC in a variety of sizes.

In Sch 80? Wow... It'll make hellva good potato gun/cannon...

[dpincus]

I can lift the board by hand. I'll use well scuffed pvc pipe.

thanks folks

dpincus

[The Bigfella]

Here's the propshaft tube I mentioned earlier.

http://i240.photobucket.com/albums/ff112/igatenby/iansecond/p6.jpg

http://i240.photobucket.com/albums/ff112/igatenby/iansecond/p7.jpg

Tape applied on a turning lathe (you could do it with a drill), epoxied and given a quick sand.... ready to install in the shaft log. This is simply 32mm diameter (1 1/4") PVC electrical conduit. The hole for it was bored with a boring bar we made ourselves, then epoxied to seal it and scuffed with a sanding mop.

Next step, slop on the goop and install.....

[ssor]

Polyester resin sticks, bonds, adheres etc. to pvc and epoxy bonds to polyester.

[Ian McColgin]

Query for another Ian: Why glass a tube that's going into a log anyway? Any gaps will be filled with epoxy either way.

[boylesboats]

Polyester resin sticks, bonds, adheres etc. to pvc and epoxy bonds to polyester.

Epoxy do pop loose from poly based plastics...

[The Bigfella]

Query for another Ian: Why glass a tube that's going into a log anyway? Any gaps will be filled with epoxy either way.

It stiffens it up, so it won't bend - not that there's a huge gap for it to bend in - and it gives a better shot at making sure there's no air gaps in there when it goes in - and then its an easy roughened epoxy to rougened epoxy bond during installation. Besides, Bazza told me to do it and I haven't found him to give me the bum steer yet. I'll check with Bazza what his reasons are.