Balsa,Klegcell or Honeycomb?

[ScottyG]

I am in the process of recoring my Vector.I was wondering from those who have done recores what material did you use and how happy are you with the outcome.It seems most but not all put Balsa back in.Scotty

[jponfrank]

Scotty why don't you trash the vector and sell me the 2.5. I know where there is a nice 16ft John Dory for sale. Joe

[ScottyG]

Joe, If you remember, my Dory although only rated for 25hp had a 50hp Merc on it.Hey,check your e-mail, give me a call and lets go drink some beers and talk about the "old days".Scotty

[activator22]

First let me say I haven't done any re-cores, so take what I say with a grain of salt - however I am in the process of replacing my floor and have spent a good deal of time researching and actually laminating and weighing various core materials and talking with the techs at FCGI

Foam (specifically Kelgecell) will give you a lighter re-core than balsa at the expense of costing more. You can recoup some of the cost though by using polyester resin, where with Balsa you really should use epoxy so it can saturate the wood. Klegecell won't rot.

Balsa is the most cost effective, but will weigh the most when done, especially if you are careful to saturate the balsa to avoid it rotting in the future, if you aren't careful, it will rot if water gets in it.

The only honeycomb that I have been able to hand laminate without the use of pre-preg or vaccum bagging has been Nida-core, I tried Nomex and it was quite difficult to get good adhesion to the whole core with the laminate, Hexcel (aluminum honeycomb) was even more expensive, harder to laminate and I have questions about it longevity when exposed to water.

[vector mike]

I am in the process of recoring my Vector right now. I am using just what they use in the factory, PLYWOOD. There must be a reason why they use it besides cost. From what I have heard and read, wood is stronger per square inch then any of the other coring materials.:)

[Rickracer]

Hydrostream didn't use plywood for coring, they used balsa wood. They did use plywood for transoms, seatboxes, and other structural parts, but not for coring. :cool:

[H2Onut]

Kleg 75 and epoxy resin, strong and light, thats all I got to say bout that. I recored a vector with klegcell 75 and 3:1 epoxy resin. Talon 2.5 Rickracer, Shorepounder and BLeonard can fill ya in on the weight deal, but its pretty darn light. I made a hybrid transom out of Transom Cast epoxy sanwiched between and stainless plate in the center.

[ScottyG]

H20NUT, Did you have to vacumn bag to lay the Klegecel 75 onto the inside of the outer hull and did you have to vacumn bag to lay the inner hull ontop of the Klegecel 75?Thanks,Scotty

[vector mike]

The only repairs that I have made are the floor, transom, stringers, and seat mounts which were all plywood. Actually the stringer was a 2x4 with a 2x2 on top of it covered in glass. The only time I saw the balsa wood was when I removed the wedge on the pad and I don't know how you would even begin to replace it without removing the whole pad. Fill me in here since I have never had to replace the balsa wood.:confused:

[Rickracer]

Basically, you have to chip it out a chunk at a time. Here's mine with most of the core removed. BTW, I have a chunk of coring out of Skips boat from a past repair, it's either klegecell or airex. That stuff is tough, lightweight, and very strong. I'd use that over balsa anyday. :cool:

[ScottyG]

Vector Mike, You recore from inside the boat.Basically you are removing the last-upper layer of glass(The hull is a sandwich:Gel/Glass/Balsa core/Glass)Scrape out the balsa core,replace with a product of your choice and glass on top.Of course I am over simplifying the process but that's it in a nutshell.I will try to post pics when I get my hands on a digital camera.Scotty

[H2Onut]

nope, vavuum would have been ideal, just rolled all the bubbles out, lay pltic wrap over it and lay sandbags on it to compressess and dry. Epoxy is a little bit harder to work with, your pot times are shorter and it dries hard so sanding is a bitch. But if ya going to do it, do it right, many have used balsa, Boatmender has a good thread and instigator did balsa, but after ripping soggy wet stinky balsa out, was no way I was putting it back in.


TO remove old, an air chisel works wonders. make sure boat is well supported from bottom also. that is real important.

Look at those threads, www.hydrostream.org has some good articles as well. worth gether all the information and go for it.


I got my supplies at

www.fgci.com

[H2Onut]

.

[H2Onut]

..

[H2Onut]

yummy

[sho305]

I talked to a guy at Checkmate about my old '73, and he told me it was not cored as it was so old. Also said it did not have floatation in it either. It does not. The sides look like big matting in the inside under the carpet. I know the seat stands and transom are plywood, guessing the floor too. Did they use more stringers this way and just make the skin thick? He seemed to know a lot about it, and said it should be lighter than the new boats but the data says 930lbs for a 17' BR.

This Bayliner I just put a transom in was that way with 3/4 only in the center of the (90hp rated) transom, and a 4" chunk for the ski hooks. The rest was a good 3/8" of solid resin/mat. You could see the pieces of wood from the inside. Also the metal gas tank has worn into the floor in back and I could see light from under the boat it was so thin. Had to beef that up, so there is no wood in the bottom. Spent two damn hours tonight trying to get the lower unit back on that Force. Done twenty or more, but they did not have a stupid rubber seal that falls off every time you miss the splines. A special thanks goes to those engineers that I will not repeat here.

[ScottyG]

H2oNUT, Thanks for the info.I am leaning towards Klegecel 75 especially after seeing and scraping out all this wet smelly balsa.I have read both recore stories at the Hydrostream owners site so I think I know what to do.Thanks again for the pics and the info.Scotty

[H2Onut]

No Problem, If I can be of ANY help, drop me a line!:D

[vector mike]

How can you tell if the coring is bad? The wood is easy to tell but how can you get to it to see if it is bad? Also, how would it get bad if it is sandwiched between two layers of glass? One more thing, has anyone removed the flotation rails along both sides under the top that are glssed into the bottom.(On a Vector) There seems to be alot of wasted space there. I also need to find a spot to mount my battery and in the back is this glassed over flotaion taking up all this needed space. My Viper doesn't have any of this in it and I'm wondering if I can take it all out or is it used as support too?:confused:

[H2Onut]

It will be a different color than surrouinding dry coring, Look for dark spots, an esy way is an Ice pick or drill a small hole if water seeps out.......... it will tell ya real quick. also soft area. How does water get in, stress cracks, shoody glass laying, poped bubbles in glass, wear and tear, in Northern states water freezes...and well you get the picture, standing rain water.

I saw somewhere that a guy built in a vent fan when he recored his boat, when in strorage circulates air to dry it out.

My Vector had 2 foam logs in the bow, ooops they've gone a missing. Flotation is my life jacket and 1500 gph bildge pump:eek:

[Rickracer]

Polyester resin is not waterproof unless it's sealed (gelcoated). I believe epoxy is though. Right Nut?:cool:

[vector mike]

This Vector has flotation glassed in on both sides on the bottom, stuffed up into the top but not glassed over on both sides and a big chunk stuck up under the bow. My Viper only has a piece under the bow. I guess somebody wanted to make sure that this Vector didn't sink. Is the stuff down both sides on the bottom that is glassed over also used as support? If it isn't, it may also come up missing because the stuff under the top sides will soon disappear while I have the two halves sepperated:)

[captcarb]

If you tap on the bottom from the outside, the wet areas will sound "dead" compared to the good areas. I use the butt end of a wooden handled hammer.

By the way, I have a 1977 Hydrodyne with a balsa core that has never had any water. The balsa is put in "end grain" with the filaments running vertically and dipped in epoxy resin before putting it in.

I could give you the phone number for the guy that still builds these hulls, if you would like to discuss his procedure.

Jim

[H2Onut]

Epoxy = waterproof

Harder to sand

Shorter pot life (at least my mixes were)

More expensive

But, alot stronger and waterproof.

[Talon2.5]

I have a chunk of coring out of Skips boat from a past repair, it's either klegecell or airex.

i do believe it was klegcell, and man that is some good sheot!!!

[Rickracer]

You mean this stuff here????:cool:

[Rickracer]

:cool:

[Rickracer]

:cool:

[Techno]

Epoxys pot life is very long. But it is heavily dependant on how much you mix at one time and what the containers shape is. If you mix up a lot and put it in a beer can it will kick off quick. If you put it in a baking pan- spread out so the heat doesn't concentrate then its fairly long.

If you use a pump system and only mix a 1/4" depth in a bison chip dip container it is very long. keep pumping and mixing as you go and you won't have the "smokies" and $$$ of wasted epoxy.

If you have a dog then obtaining mixing containers is easy. Whatever little plastic tub you buy give it to the dog when its empty and they'll do a fantastic clean up for you. Stack them somewhere for future use.
A gallon jug with half cut away but the handle still attached works pretty good too. Only need 2-3" of depth on the new container. the handle is above the resins so stays cleaner too. Holds more than a chip dip container at the same depth.

[Rickracer]

Take an old antifreeze jug with the top screwed on tightly, and basically cut out the label, making a window in the side about 8"X10". Then you lay it on it's side. Big enough for dipping, nice handy handle, flexible, but not too flimsy, and re-usable. After the resin hardens, you can bang it on your knee, and the old hardened resin pops out. Voila, re-cycling at it's best. When it no longer pops out cleanly, grab another jug. Most garages will save a few old jugs for ya if you ask em to.

[Techno]

But my dog doesn't like anti-freeze.

I like that idea you can lay it on its side for a large amount or stand it up for smaller amounts 2 in 1.

[vector mike]

Is that a Vector in the pictures? It looks like it had those long rails down each side. Did you install anything back in there for strengh or just leave it all open?

[H2Onut]

You get long pot life but wil temps pushing 100 and humidity at about 96% , Pot life is short term 15-20 minutes MAX, I get at least 30 from poly. Granted shape of container plays alot to do with it. I ended up puttting epoxy in a coffe can and setting it in a bucket of ice, it slowed trigger time alot.

[Rickracer]

That's about as far as that project has made it, so far. My plans include Klegecell coring. , and virtually no flotation. No, they won't be going back in. :D

[vector mike]

So I guess they arn't used as some sort of support, just floation.

[Techno]

H2Onut
2 relativety items. I mix my poly for fast cures, why I usually use it. The epoxy normally is much longer than this. With the west system you can also get the "slow" hardener for someone in your situation. But would probably be that time you said. 20 minute pot life is long for me.
Old Einy had it right when he said "everything is relative".

I thought all youse people down there had ACd garages????

[H2Onut]

Garage..whats that, Vector restoration 100% in the elements...it sucks big time...possums, dogs, lizards, nats, debris is air, hot hot hot hot.....

But the paint is DONE just finished yippeeee

[Techno]

Garage- a repository for cars that don't run, yard tools that aren't used, parts that will never be re-used, "garage" sale items previously bought with no place to go.
I'm outside too and I have 2 car garage!

[sho305]

Did this Bayliner transom under a nice Maple tree. The ants would fall into the boat and get trapped in the splashwell. Right in front of my face there would be 20-30 ants trying to climb out. Too stupid to go down and out the drain after I drilled it back out even. Thought I would spray bug stuff around the tree, then I had drunk ants stumbling around in there instead. Could not plug up the garage that long, but put it in there when it rained. I prayed to the garage-gods every day for that new polebarn...

I re-sprayed the lower unit last night as I scratched it on install, had bugs getting stuck in there and stuff. Not getting too fancy on this rag so no big deal. I used car paint, we will see if it lasts. This thing has no anode, so have to bolt something on there.

[Ro Yale]

I've done several streams in the past 20 years. H20nut is telling you right no use to discuss further!
Later, Ro:D :cool: :D :cool: :D :cool:

[Alan Power]

Hey scotty,

I have done a good deal of research into composite construction, and while saving weight with foams and honeycomb you sacrifice strenght in various ways. Although it is the most cost effective balsa shouldnt be looked at in a negative way it has extremely good propertys when laminated correctly and can yield the best glue line adhesion without the use of a vacum pump.

Another way to go would be to use multiple types of core in critical area's depending on their properties, check out www.spsystems.com in the introduction to core materials section, good info
and nice graphs to illustrate various properties.

Also a vacum cleaner makes a good cheap vac-pump
for doing small areas would probably work OK if you decide to do the boat in sections.

If you have any other questions you can email me on alanp@iol.ie, but I'll be away for 2 weeks from tomarrow, will check back then.

Regards;
Alan...