Nidaplast Honeycomb Core

Discussion in 'Fiberglass and Composite Boat Building' started by bundaberg42, Apr 16, 2012.

  1. bundaberg42
    Joined: Apr 2012
    Posts: 5
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Australia

    bundaberg42 Junior Member

    Nidaplast Honeycomb Core, can it be used to replace plywood 18mm on cabin decks and roof as per this boat ? There doesnt seemed to be any comparison to ply other than you have to have some sort of engineering degree to understand the specifications .

    following is the stuff i was thinking about , being plastic i thought well this is not going to let rot back in

    this is boat im cutting rot out of , pretty much all the windows are rotten and some part of the cabin roof maybe half a sheet , all about 18mm thick.

    I would really apreciate it if some one knows much about this stuff as it seems to be good match to epoxy
  2. tunnels

    tunnels Previous Member

    Have laid quite a bit of Nida core !!, laid it into just 450 wet csm pull a thick bag over it and suck some of the air out !!! ,just enough to hold it against the wet glass only So be very carefull and watch what you are doing !!!. by using vac it takes all the guess work out !!,is its incontact with the surface underneith or not . Dont need peel ply or anything else just a bag thats all . Light pressure only !! Just enough to hold it against the wet csm glass till its gone hard .
    Finishing the edges were always a hassle till we started to make and use foam the same thickness cut on a 60 degree angle and placed that around all the edges !!! Made life easy to glass over when it was hard !!, just a block sand to get rid of any dags or hight spots !!.
    Tried taping but was a mess and to rough!!!! the foam core worked a treat and put in at the same time and sucked it all down together !!:D:confused:
  3. Alik
    Joined: Jul 2003
    Posts: 3,076
    Likes: 363, Points: 93, Legacy Rep: 1306
    Location: Thailand

    Alik Senior Member

    PP honeycomb can be used almost anywhere in structure excerpt bottom panels of high-speed and relatively large boats. Shear strength of PP is comparable with 60kg/m2 foam, this means that panels (between stiffeners) should be smaller and one might need thicker FRP skins. Compressive strength is higher compared to foam. We use PP widely in many designs of pleasure and small commercial craft, never had issues of delamination, but of course should treat this material properly.
  4. Jetboy
    Joined: Feb 2012
    Posts: 278
    Likes: 6, Points: 0, Legacy Rep: 65
    Location: USA

    Jetboy Senior Member

    I'm interested in this topic as well. I'm building a small 18' tri out of PP honeycomb (plascore). I laid up the first three sheet panel this weekend. I found that it took quite a large amount of resin compared to what I had anticipated.

    What are your thoughts on vacuum bagging it? Tunnels seems to like it. I'm concerned about having really heavy print through of the honeycomb. Has this been an issue? Have you had problems with sucking resin into the open cells?
  5. tunnels

    tunnels Previous Member

    The only way to get it down and 99.9% stuck is to use a light vacuum other wise you are just guessing !! :D
  6. Jetboy
    Joined: Feb 2012
    Posts: 278
    Likes: 6, Points: 0, Legacy Rep: 65
    Location: USA

    Jetboy Senior Member

    How much print through are you getting? Also how much vacuum are you using? I don't have a vacuum pump yet, but the ones I've looked at don't seem to have a good regulator to do low pressure vacuum. Are you using a traditional vacuum pump?
  7. tunnels

    tunnels Previous Member

    I found that it took quite a large amount of resin compared to what I had anticipated.

    What glass did you lay and how much did you put down (number of layers and glass weight ) ??

    What resin are you using ?? polyester ? vinylester ? epoxy ? There is only 3 ,but are differant !!

    Ok how did you work out the amount of resin you were surposed to use ??

    Each glass type and weight will use differant ratios of resin to glass plus hand layup can use a little more than you think !!

    Print throught as in what ?? glass print ??or core print ??

    You dont need a lot of suck pressure !! two bits of wood and a clamp on the hose will form a regulator just watch as its coming down and make sure its firm pulled firm and even but not tight!!
    Do a small dry test run first and get the feel of what you are going to be doing !!! Vac is a interesting medium to work with and you can do interesting things with it !!. :p:):D:D:D:p:p
  8. Jetboy
    Joined: Feb 2012
    Posts: 278
    Likes: 6, Points: 0, Legacy Rep: 65
    Location: USA

    Jetboy Senior Member

    I'm using epoxy. I used approx 1 gallon to wet out the factory veil and 12 oz 0-90 biaxial over 4' 20'. So approx 9 yds or 6.6lbs or fabric. 1 gallon of epoxy weighs about 9lbs. So I'm using about 20-30% more resin than expected. However I believe the factor veil is where most of the extra resin is being used. The veil soaks up a lot of resin. That was something I hadn't planned for.

    Not a huge deal, but will add some weight and add more resin cost to the build. I'd love to have a better way to use less resin and compress it, but I don't think vacuum bagging will do that for me as it will just pull more of the resin into the cavities.

    As far as print through, I'm talking about the honeycomb cells - the surface of the finished fiberglass being compressed into the voids so that the final surface would be dimpled. That would make for a lot of work in fairing the hull.
  9. tunnels

    tunnels Previous Member

    So you use Veil!!!
    What for ??
    Did you lay the veil ,let it go hard and then put the 0/90 over the top ?
    If you did next time Lay the veil and the 0/90 straight in on top and roll them out together !!. you can get 0/90 with a light layer of csm attached so dont need the veil and if you are useing epoxy you really shouldnt need veil any way
    Epoxy has the lowest shinking rate of all the resin systems !!!
    The more resin you put on the more the layers of glass with float and separate and you get a resin rich thick layer !!!.Better to use peel ply over the top of the wet rolled out layers and apply your resin with a paint roller then steel roll it all together starting from the middle alsways and pulling to the outer edges !!, make sure the peel ply looks shiney wet on the surface all over when you finished then let it harden and peel it off !! .
    Vac the core down lightly is the only way to make sure your core is bedded properly and consistantly all over !!:D

    I work with a bunch of know it all experts that load lots of bits of concrete all over everything !.
    The last deck we did was a complete disaster with pockets of air bubbles here and there and every where that had to be dug into and ground out and patched and so weakened big patchs of the deck !!
    Repairs are never as strong as the original laminate !!!
    So far they had 4 goes at it and still there are pockets that keep coming up as we slowly creep into summer and the weather gets warmer so and the air inside the bubbles exspands and pushs against the surface !! If they had vacuumed the core down it would never happen !! Some people never listen and think they know it all !!. :eek: The other small problem as they never wet out the core properly before it was laid into the wet layer of glass so its dry almost in places , like the bubbles are the thickness of a sheet of paper but about hand sized and bigger !!. Idiots !!. :rolleyes:
  10. Jetboy
    Joined: Feb 2012
    Posts: 278
    Likes: 6, Points: 0, Legacy Rep: 65
    Location: USA

    Jetboy Senior Member

    The Veil comes from the factory attached to the core. Epoxy will not bond do polypropylene. The veil is polyester fabric that is bonded to the PP core. It needs to be wetted out along with the fiberglass so the glass and veil are bonded together. I wet out the veil first, then lay the fiberglass and work out all the wrinkles and bubbles. Then I use a knife (tapers knife - like hard card/scraper) to work the glass onto the veil. I usually use 80% of the resin on the veil first, then about 20% worked over the top to ensure it's all properly wet out. Once it's wet, it is clear through to the PP core, and I can see all the cells. At that point I can be sure there are no air bubbles. The finished product seems very good. I have no blisters or visible imperfections. I was just surprised by the amount of resin I needed to get a good wet out - mainly due to having to wet out the polyester veil in addition to the fiberglass.
  11. tunnels

    tunnels Previous Member

    Bubbles !!

    :confused:This what happened to the deck that they use concrete weigths to hold the core down into the wet glass . instead of using vacuum to suck !! this is just a few theres lots more :idea::?::p
    Has to be dugg out from behind and repaired !! its getting up to 8 months agao and the glass has cured in that shape and is rock hard to me its a write off !! thai is just a small part of the problems there lots more !!

    This in the non slip areas of a deck on a 28 fooboat we still have sitting in the factory !! To take good photos i waited till the late afternoon and got shadow and then enhanced the photos to make them really stand out !!! but this is just a fraction of whats on this deck !!,The picture look much worse than they really are !!
    Its just a standard production boat nothing special just the bubbles are special .
    Over the years i have taken hundreds of pictures of laminating problems and the causes have always been the same !! Bad workmanship !!!

    Attached Files:

    • 003.JPG
      File size:
      1.3 MB
    • 001.JPG
      File size:
      314.9 KB
    • 004.JPG
      File size:
      1 MB
  12. sabahcat
    Joined: Dec 2008
    Posts: 792
    Likes: 28, Points: 0, Legacy Rep: 273
    Location: australia

    sabahcat Senior Member

  13. Jetboy
    Joined: Feb 2012
    Posts: 278
    Likes: 6, Points: 0, Legacy Rep: 65
    Location: USA

    Jetboy Senior Member

    What is the material blistering in your pics tunnels? That looks nothing like the fiberglass I've seen before.

    Anyway I only had a couple small blisters on one test layup when I didn't use enough expoxy. Otherwise I get a good full clear wetout.

    It looks like this from the factory:

    Then with fiberglass like this:

    These are not my pictures BTW.

  14. tunnels

    tunnels Previous Member

    If you are putting that core onto a wet layer of glass and with a light suck down you should not have to pre wet the core at all !!. :D:p

    That bottom picture looks like the cell is filled with resin !!:confused::idea::idea::?:
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.