Question on Epoxy

[propnut30]

OK I have been stocking up on supplies to carry out my refit/restoration/mods while deployed and Im close to coming home. Thank you Lord! Now I started to stock up on epoxy (west system) and was stopped. West Marine canceled my order for some strange reason, I tried to reorder and the shipping was double what it was the first time. So rather than order it Ill pick some up when I get home and go on vacation. Will save the money in shipping.

Heres what I am looking at getting, 105 resin, 206 slow, 205 fast, 207 special coating, 422 barrier coat additive, and some of the other fillers. for each can of hardener there will be one matching can of resin and meters. I should never have to run out between my hobbies home projects and hobbies this should be enough.

Most of what I want to do I replace the bulkheads and other wood panels in the boat, add some shelves and a better galley. Also refinish the existing wood trim inside and out. Is the 207 overkill on the interior wood? I'm going to be using okhume plywood for the flat stock. Being moisture is a common issue in a mac, why not seal all edges and call it good. Using this stuff I'm looking as roughly $190/gallon of resin and can of hardener.

As far as the rest of the resin n stuff, I want to clean up the area below the liner and inside. Where the Liner was joined to the hull, there are lots of rough edges and places that cut or leave glass splinters and gathers debris. I am still debating this part of the job, Unless you reach in those areas a lot, you wont know it is like that. It will serve no function toward better performance either. I will likely leave this alone. I do have some cracks int he hull to be repaired other places to be beefed up some. There is one area that looks like it was hit by another boat, not bad just scarred.

Am I well covered on the composite's or are there others that I should add to the gear. I kno the exterior wood will need uv protection.

[RobertB]

West System is good but not the only game in town.

I have used MAS epoxy alot and had great results. See http://www.clcboats.com for some good kit prices. They make their money on boat kit sales and sell the supplies for good prices

[propnut30]

I appreciate the advice and the link. I like that they have the kits set up so all you need to do Is decide what size you need. Thanks

[Ixneigh]

I generally regard West as top shelf resin. I only use it for critical stuff like lightweight bonding and taping or sheathing in light glass. Any place where weight is not an issue I'll use cheaper stuff. My windlass project was all done with fastco epoxy. I do think for sealing bare wood West is a very good choice. It has a thinner consistency. You will probably need to apply as many as three applications.
Ixneigh

[RobertB]

West System is top shelf but not alone. MAS has always had some very strong characteristics such as low blush (most epoxy when it cures develops a film that must be removed between coats). System Three is also a premium epoxy. I have used all three products - the decision should be about price and availability. While West Marine only sells West System in the stores, notice that it sells MAS in the catalog. Chesapeake Light Craft has always only sold "top Shelf" since if they sold inferior epoxy, they would not be still in business since the epoxy is a critical component of the boat kits they sell. John, the owner, if I remember correctly, has never sold West System primarily because of the cost of not just the epoxy but of the related fillers and accessories.

I built two boats with MAS and never found any characteristics that would put it in the "cheap" category.

[DaveB]

Why not use Polyester resin? Bulkheads require space about 1/4 inch for spreading hard spot, foam fill to prevent stress at one location. You need to flair it.
Epoxy is great but 4-6 times the cost of polyester resin.
Shelve life in both products is short. (3-6 mo.)
Always use current dated resins.
Dave

OK I have been stocking up on supplies to carry out my refit/restoration/mods while deployed and Im close to coming home. Thank you Lord! Now I started to stock up on epoxy (west system) and was stopped. West Marine canceled my order for some strange reason, I tried to reorder and the shipping was double what it was the first time. So rather than order it Ill pick some up when I get home and go on vacation. Will save the money in shipping.

Heres what I am looking at getting, 105 resin, 206 slow, 205 fast, 207 special coating, 422 barrier coat additive, and some of the other fillers. for each can of hardener there will be one matching can of resin and meters. I should never have to run out between my hobbies home projects and hobbies this should be enough.

Most of what I want to do I replace the bulkheads and other wood panels in the boat, add some shelves and a better galley. Also refinish the existing wood trim inside and out. Is the 207 overkill on the interior wood? I'm going to be using okhume plywood for the flat stock. Being moisture is a common issue in a mac, why not seal all edges and call it good. Using this stuff I'm looking as roughly $190/gallon of resin and can of hardener.

As far as the rest of the resin n stuff, I want to clean up the area below the liner and inside. Where the Liner was joined to the hull, there are lots of rough edges and places that cut or leave glass splinters and gathers debris. I am still debating this part of the job, Unless you reach in those areas a lot, you wont know it is like that. It will serve no function toward better performance either. I will likely leave this alone. I do have some cracks int he hull to be repaired other places to be beefed up some. There is one area that looks like it was hit by another boat, not bad just scarred.

Am I well covered on the composite's or are there others that I should add to the gear. I kno the exterior wood will need uv protection.

[ChuckieTodd]

I personally don't trust new to old bonding with polyester resin. When it cures, it shrinks creating internal stresses.

[propnut30]

I will admit they poly is cheaper, but I have read about delamination and shrinkage also. I also have not seen a poly that gave a good finish to wood. I do want to have a good finish that is clear at least on the woodwork. I may go with the Mas, the main deciding factor between West and Mas will be whats available locally. After seeing $28 for shipping and the distance was only 40 miles, I will just wait till I get home to pick it up. I'll be at Morehead City and there are quite a few locations that carry epoxy. Will also be pickin up the wood for the boat to. Found a place called Atlantic Veneers that carries all kinds. They work to supply local boat builders and shops. Ill be using Okoume ply on the interior. A few other projects I have lined up include making molds and door and interior panels for a car I'm working on. Gettin super hard to find original parts for a 15 supra so ill just go custom. I did simular making plug molds for an RC boat hull, out of foam than use the plug to make a female mold from epoxy. This will just be a much bigger scale.

I didn't know Epoxy has such a short shelf life though.

[propnut30]

I did a little checking this is what i found. SOURCE: http://www.westsystem.com/ss/storage-shelf-life


Store at room temperature. Keep containers closed to prevent contamination. With proper storage, resin and hardeners should remain usable for many years. Over time, 105 Resin will thicken slightly and will therefore require extra care when mixing. Repeated freeze/thaw cycles during storage may cause crystallization of 105 Resin. Warm resin to 125°F and stir to dissolve crystals.

Hardeners may darken with age, but physical properties are not affected by color. After a long storage, verify the metering accuracy of the pumps and mix a small test batch to assure proper curing.

I used up to now mostly hobbico brand epoxy but those are thicker and in small batches. The finishing epoxies are thine and not as flexible. But I never had any problem with them sitting for a year or two. Polyester, I had a can of that crystalize in my Dad's shop, but God only knows how old it was.

[Ixneigh]

Epoxy has a longer shelf life then poly. It will adhere better to old poly structures.
A subspecies of poly called vinyl ester reportedly has almost as good adhesion to old fiberglass but I still would not use it on wood. For wood, epoxy is the way to go.
What goes bad the fastest in the poly resin is the clear liquid hardener component MEK. Always buy new MEK for any project even if using older resin.
I've used epoxy before but did not like it as much as west. Mas and steel flex seem about the same to me. I use steel flex all the time, but prefer west if cost is no object or for low volume high strength applications.
Ixneigh

[raycarlson]

I'm with DaveB, use poly anywhere you can,its way cheaper and structurly just as strong and bonds just fine if preped well.last place you want to buy epoxy resin is west marine.way overpriced for a re-labeled product.check the three largest commercial fiberglass supply houses, they also sell epoxies to boat manufactures and you can get a much better price,or if you know any one in the aircraft repair field you can get their expired 6month old stuff for free because the FAA requires them to throw it out after 6 months.and the first time your wife or girl freind reaches under a hatch and gets a two inch shard of fiberglass under her fingernails you'll be fixing all that underliner unfinished glass work that macgregor is to cheap to finish due to labor cost.I've spent a hundred or more hours under my bottom liner doing glass work and gelcoating everthing under every seat and hatch,it was well worth the effort. good luck with your project.