Maxim catamaran?

[Factor]

Originally Posted by andreas.mehlin

ehhh..name any mass-produced cats built with epoxy resin?

Not many, but a number with vinylester, which is near epoxy and light years ahead of polyester

[andreas.mehlin]

Originally Posted by bushytales

Hi...I am an Aussie currently living in the western cape SA. Have owned several catamarans whilst living in Australia. ALL used epoxy resins in their construction.
I have been staggered to discover that the catamarans being built here in SA , even today, continue to be built using polyester of different types - but still polyester! In asking why, I am told COST.
I continue to be amazed that large scale manufacturers of these catamarans continue to use poly....just be careful in what vessel you buy as regardless of what you might be told, polyester cannot compare with EPOXY in terms of strength, durability, how long it will last, water ingress, etc, etc.
best wishes

What I'm aware off...those built with epoxy is usually cold molded, strip planking, kits,. Those kind are more or less only used building one by one...Like schionning, spirit...or when carbon fibre os involved...like Gunboat etc.

Lagoons, FP, Leopard, Knysna, Outremer, nautitec....all uses polyester & vinylester

[Jacana]

As previously asked,has anyone put new engines in and what the best way to do this .Do you have to cut into hulls to get engines out and in ?Thsnks Geoff.

[Stingo]

Originally Posted by Jacana

As previously asked,has anyone put new engines in and what the best way to do this .Do you have to cut into hulls to get engines out and in ?Thsnks Geoff.

No need to cut a hole in the boat - the engines were the one of the last things to go into the boat when they were built, but things like the alternators, air filters and the like were removed and then reattached once the engine was in place.
There is a Maxim Owners group on Fakepoo and IIRC, there are a few owners there that have replaced engines, so are in a better place than I am to comment (although I did watch my Maxim being built, so watched them get the engines in through the cabin doors/bulkhead doors).

[Sand crab]

I was wondering about the older post regarding the 40'. Did they build these and were they a stretched 38' or a new design?

[Stingo]

They stretched them from 37 to 39 in about 2004. The last one was built in 2007 and then Maxim closed down.

[Go Wildcats]

This guy did a simple test (yes, very simple) on resins and deflection. While the vinylester results were thrown out because he believes the resin was too old to be used, the polyester and epoxy 2:1 mix were identical. When I read the comments, a great one was posted. He states that 2:1 epoxy will provide a mere 6% more stiffness over polyester. Dennis Simmons commented:

"Hi Andy. I am a retired structural engineer. The large deflection test you did (thin laminate over long span) causes the test specimens to deflect so much they go into membrane tension (think tension in the plane of the laminate like a suspension cable). Therefore, putting them rough side up or rough side down will make a difference (in theory, rough side down will create more friction at supports and permit a greater degree of stiffness during membrane tension and thus reduce the deflection). And as Todd Dunn commented, epoxy can take 4-5 days (my experience is 7 days) before you get the full stiffness. I think you should review the technical data and find which resin has the higher flexural modulus. The higher the modulus the greater stiffness it will add to the laminate. I did the homework for you and found 5:1 Total Boat Epoxy has a Flexural modulus of 450,000 to 460,000 psi. 2:1 Total Boat Epoxy comes in at 330,000 to 360,000 psi. Total Boat Polyester Resin is only 17,205 psi. So the Epoxy is your best choice for higher stiffness, with the 5:1 being the stiffer of the two. However when it comes to laminates, even though epoxy resin is much stiffer than polyester resin, the glass fibers provide most of the stiffness. 1708 fabric has 17 ounces of fibers running in +/- 45 degrees with 3/4 of an ounce of matt backing. Fiberglass fibers have a modulus of 10,500,000 psi. With 50% of this stiffness running one direction in 1708 fabric and 50% in the opposite direction, you still have an approximate modulus of 5,250,000 psi. Glass to Resin volume should be at about 60% to 40%. However, I find hand lay-ups are wetter and end up being about 50/50. So the glass in your laminate is going to provide 50% x 5,250,000 psi or an effective modulus of 2,610,000 psi. 5:1 epoxy will only contribute an additional 50% x 450,000 psi = 225,000 psi modulus to the laminate. 2:1 epoxy will contribute 50% x 330,000 psi = 165,000 psi additional modulus. Polyester will only contribute 50% x 17,205 psi = 8,602 psi additional modulus to the laminate. Summing up, 5:1 epoxy and 1708 at a 50/50 volume ratio will give a total modulus of 2,835,000 psi. 2:1 epoxy will be 2,775,000 psi and Polyester will be 2,618,600 psi. Therefore, in conclusion, the 5:1 epoxy laminate will be 8% stiffer than the polyester laminate; the 2:1 epoxy laminate will be 6% stiffer than the polyester. You will have to decide if this small increase in stiffness is worth the extra cost of epoxy or just use 10% more glass with your polyester lay-ups. Hope this helps."

https://www.youtube.com/watch?v=AfdF5gETgyc

Originally Posted by Factor

Not many, but a number with vinylester, which is near epoxy and light years ahead of polyester

[Sand crab]

That's great data but epoxy is waterproof and that is why it is better. Polyester is not, vinylester is mostly waterproof. It does seem like all manufacturers have gone the vinylester route at least in part for this reason.

[ak5609]

Hello,

So did you buy a Maxim?

Alex

[Tupaia]

FWIW Epoxy gel coats exist but are very difficult to use. Curing state between the laminate and the gel coat is critical and almost impossible in large scale operations. Without gel coat an epoxy shell will need to be painted. Not practical for production.

[rustyrusty]

Any one like to give me a valuation of a Maxim 38 with lots of good gear motors done 5000 but new legs.. Its in Qld No a lot of good boats around..

[ak5609]

There is a Facebook group of the Maxim 38.

[Jrwil1]

Love my new to me Maxim 380, but what is the procedure to lower the geona?

[chrisr]

Originally Posted by Jrwil1

Love my new to me Maxim 380, but what is the procedure to lower the geona?

um...is this a trick question ?

after unfurling, i usually release the halyard and ease it down. is there another way ?

cheers,

[Jrwil1]

I know sounds ridiculous. But there is no normal halyard. I have not gone up yet but seems to be steel cable attached to head coming down inside mast and exiting maybe 4ft off deck and then attached to an adjustable rail on side of mast. Ive never seen anything like it.