Selecting the right materials for fibreglass work

[Kennedy_150]

I have a 14’ fibreglass Kennedy that’s a picked up knowing it needed a full rebuild (transom, core and stringers) got it home and got right to work building a jig so I could start the tear down. Ended up also splitting the boat because bump rail was gone and all rivets Had previously been drilled out so it was just a matter of cutting tabbed fibreglass. I now have all rot removed and am just getting rid of all leftover fibreglass, so it is time to start ordering all the materials. This is my first real fibreglass project so I have been doing a lot of research and scouring the forms. I am planning on a balsa core and using marine grade wood for the transom and stringers but was unsure about resin. I would like polyester for $ wise and have also heard it is a very suitable resin for this job, but would love to hear some feed back on that. I also had some questions about the layup and what order is best between csm and cloth and also what weights
recommended for both materials. The boat will be a 2 seat river runner and around small lakes. Thanks👍🏻

[David]

That was the boat of my dreams when I was 15. A friends family had one with a 55 Chrysler and then a 60 Merc. There are a lot of knowledgeable glass guys here who can help you. You could also get local advice from the Fastboats Canada Facebook page

[LakeFever]

I know how you feel. I spent many years plotting out restoring a glass boat. My thoughts are the best way to ensure the results are worthwhile was to use the best bonding resin I could in case my layup skills turned out to be sub par. I ended up using vinylester because it binds better than polyester over old polyester. The best bond is epoxy and it also has a major advantage for newbs because you can set the cure rate and give yourself a lot more working time.

I can say thus far ( I’m only about 20% through my layup ) that I have had resin kicking faster than I wanted three times. The first time I peeled the glass right out before it bonded it would have been a mess. Since then I have learned you get about 20-30 minutes of good work time and after that it’s a gamble pending temps and catalyst percentage.


the downside to epoxy is cost and gel coat bonding. The gel coat bonding issues was the main reason I skipped epoxy because I want to gel the hull inside and out for water protection. Vinylester is a good balance between the two where it bonds like epoxy but has great secondary bonding with poly ( gel etc )

I also chose core bond for the core and transom because it’s more forgiving on uneven surfaces and my supplier talked me into it. Seems good so far.

One of my helpers is helping me to learn how to do his and he’s going poly everything for cost reasons. It is major savings to do this but you really have to make sure the old surfaces are prepped really well to get the correct mechanical bond. There might be more I can’t think of to suggest but that was my thought process on materials. It’s fun work

[powerabout]

whats the temp where you are doing this?

[Kennedy_150]

Ya I love the look of these boats, it’s my second one. I also have a 18’ with a merc 150XRI hangin off the back

[Kennedy_150]

Thanks lakefever, I will look into vinylester, I haven’t even considered it. I also will take a look into core bond����

[Kennedy_150]

It will be mostly mid summer so 20 degree Celsius during the days and it will also be done it a garage

[XstreamVking]

Use the vinyl resin, 1708 bi-axial cloth, 1.5 oz mat and you can't go wrong. Only put back in what you take out weight wise. Small boats are very weight sensitive.

[Kennedy_150]

XstreamVking Do you recommend 1708 as base layer and also last layer down?

[XstreamVking]

1708 has a layer of 1/2 oz mat stuck to the underside. This goes against the part. You may know that already.

If the hull is in good shape then grind clean and maybe a put down a layer of 1.5 oz mat to work off of. You can roll it into the surface with no air voids. Then install stringers and such with the 1708. Pay attention to what you take out and try to replace it closely in thickness. I don't know these boats so a pic or two might help. I also like some mat to cover the bi-axial so you can grind it before gel cote is applied.

[MattGreen]

Kennedy keep listening to Xstream, he'll steer you in the right direction. The Canadians on here are also happy to help. Composites Canada and Noah's Marine (both in Toronto) both have all the supplies you will need. Some pictures would help.

Matt

[Kennedy_150]

486394486395

[Kennedy_150]

i have added pictures of the boat and ya i was planning on Noah's marine for supplies.