Honeycomb Use

[Saqa]

http://www.duroplastic.com/polypropylene-honeycomb.html

Can panels cut from this stuff be bent over frames and stitched using cable ties then taped and sheathed with glass the way ply is used?

Can cotton or uncoated spectra fishing like be used with a suture needle if cable ties cause too much damage?

 

[upchurchmr]

Are you asking if you can make a laminate with core and one skin of glass?

Probably but you loose the major value of core if you don't have glass on both sides

What do you see as the benefit?

 

[Saqa]

I was under the impression that it is best to sheath both sides of ply, and intending to do the same with honeycomb but for sandwich construction reasons. I just dont know if it can be stitched together like ply before taping and glassing

 

[Tungsten]

I've seen small boats stitched with this material, it bends easy with out glass.Typically the joins are glassed heavily so a few holes from stitching isn't a big deal.

 

[whitepointer23]

it does say that it is suitable as a core material between aluminium , ply , steel and fibreglass. it also states it is suitable for long term water immersion. your link answers your questions if you read it.

 

[Moggy]

Looks like polycore or nidaplast... best with glass both sides I understand. You just butt join it.

 

[Saqa]

I've seen small boats stitched with this material, it bends easy with out glass.Typically the joins are glassed heavily so a few holes from stitching isn't a big deal.

Good to know that its compatible with stitching, I guess a suture needle with some spectra line be good and can be left in there after epoxying and filleting

I am now trying to find out about repairing hull damage with honeycomb but information is hard to come by

it does say that it is suitable as a core material between aluminium , ply , steel and fibreglass. it also states it is suitable for long term water immersion. your link answers your questions if you read it.

Yup, all that info is there but they dont mention anything about securing the cut panels together with ties which is what I am trying to learn about

Looks like polycore or nidaplast... best with glass both sides I understand. You just butt join it.

I take it you mean butt joined at the chines? All the info on the sites are about securing to a mold with screws and nails but no info about just stitching panel edges together instead. Leaves me wondering if its unsuitable for that

 

[Tungsten]

Repairs can be a ***** since nothing sticks to the poly core,people probably over glass for this reason.

I think what Moggy means is panels can be just butt jointed then glassed over to make bigger panels.

 

[Pericles]

This might help.

http://www.bateau2.com/howto/foam1.php

 

[upchurchmr]

If nothing sticks to poly, then there is no value in using the honeycomb, except as a form.

 

[Moggy]

I take it you mean butt joined at the chines? All the info on the sites are about securing to a mold with screws and nails but no info about just stitching panel edges together instead. Leaves me wondering if its unsuitable for that

Anywhere, I was looking at making a hard deck in the stuff (Polycore) and I needed 1.5 sheets each side. Apparently you just butted it up, laid glass over the whole job then same the other side. I didn't go through with it but I guy I know did one, said it was remarkably stiff and strong. He used 15mm which is their thinnest structural grade. Apparently it has limited flex, that may be an issue.

 

[Moggy]

If nothing sticks to poly, then there is no value in using the honeycomb, except as a form.

Resin sticks to the scrim which is bonded to the core, the 'end grain' is where you have issue sticking stuff to it.

 

[Saqa]

I am ruling out honeycomb for repair reasons. Need something thats easily repaired when holed or smashed.

 

[Alik]

We design a lot of boats with use of this material. need to know some tricks on how to handle it, also for repair. As big advantage, material is cheap, never delaminates as foam, compressive strength is high.

Disadvantages: lower shear strength compared to foam of same density. Say, 0.6-0.8MPa for best brands, 0.3-0.5MPa for others; it will correspond to 60kg/m3 foam while PP honeycombs will give about 100kg/m3 in structure.

 

[Moggy]

I am ruling out honeycomb for repair reasons. Need something thats easily repaired when holed or smashed.

It is actually very difficult to hole or smash, the stuff is surprisingly resilient. I can't see why it would be difficult to repair. There is a story out there somewhere about a boat made of the stuff that was written off for some other reason (I forget) but apparently when they set to and tried to destroy the structure it became a real problem.

http://www.buildacat.com/lyra1.html