Composites Central


Reply
Old 08-23-2013, 04:25 AM   #1
compoforo

Member
 
Join Date: Aug 2012
Location: Cantabria
Posts: 111
Thanks: 31
Thanked 10 Times in 6 Posts



Default Sandwich panels edges finish

Hi all, I have a question about panels, I have observed that many people do not use core over all surface of the panel, they make edges without foam, however I don't understand why. I think while more surface have core in your panel, best weight / stiffness going to get because it will produce more sandwich effect and you could use lighter skins.

So, why you do this? Saving foam?

I see this particularly in skate manufacturers:




Regards

Last edited by compoforo; 08-23-2013 at 04:51 AM.
compoforo is offline   Reply With Quote
Old 08-23-2013, 05:27 AM   #2
PabloB

Forum Donor
Member
 
Join Date: Oct 2012
Location: Spain
Posts: 11
Thanks: 12
Thanked 0 Times in 0 Posts



Default

Do you mean leave the core expose in the borders?, if that the question you alredy have your anwser, and is easier to infuse, or for wet layup and bagging. Beside that you will have extra work after. I don't know if my english is understandable)
PabloB is offline   Reply With Quote
Old 08-23-2013, 08:17 AM   #3
susho

Composites Expert
 
Join Date: Dec 2007
Location: Lemmer, the Netherlands
Posts: 537
Thanks: 10
Thanked 72 Times in 67 Posts



Default

it is for me :P

why? Because it's easier/faster/cheaper. I like Urethane sidewalls more, like used in kiteboards. Much better finish.
susho is offline   Reply With Quote
Old 08-23-2013, 10:39 AM   #4
compoforo

Member
 
Join Date: Aug 2012
Location: Cantabria
Posts: 111
Thanks: 31
Thanked 10 Times in 6 Posts



Default

Quote:
Originally Posted by susho View Post
it is for me :P
You already have a very good boards , these board,like you say, are made thinking on profitability, I don't think that they are better than your boards .

Quote:
Originally Posted by susho View Post

why? Because it's easier/faster/cheaper. I like Urethane sidewalls more, like used in kiteboards. Much better finish.
I think same, but maybe, the examples I have given were too oriented to Easier / faster / cheaper, but it is these others I haven't so clear:


This deck costs about $ 1,000 O:, Easier / faster / cheaper should not be a goal here.






In these cases I don't see that the target is Easier, cheaper or faster, for example, cut just where the foam ends, is useful because you do not need a template.
I've only seen a manufacturer bearing the foam to edge! this make me doubt ... perhaps cosmetic reasons?

Another possibility that could be is that first manufacturer made of this form and everyone else did same after...

Regards!
compoforo is offline   Reply With Quote
Old 08-24-2013, 03:18 AM   #5
susho

Composites Expert
 
Join Date: Dec 2007
Location: Lemmer, the Netherlands
Posts: 537
Thanks: 10
Thanked 72 Times in 67 Posts



Default

Wefunk, nice boards, prepreg carbon (but a 1000 $? I'll need to build more of mine and start selling, could be way cheaper and still make a nice profit, haha)
Quote:
Another possibility that could be is that first manufacturer made of this form and everyone else did same after..
Seems like that. I borrowed my PU sidewall from kiteboard building. I guess Loaded had the same idea around the same time :P
susho is offline   Reply With Quote
Old 08-24-2013, 11:34 AM   #6
compoforo

Member
 
Join Date: Aug 2012
Location: Cantabria
Posts: 111
Thanks: 31
Thanked 10 Times in 6 Posts



Default

Quote:
Originally Posted by susho View Post
Wefunk, nice boards, prepreg carbon (but a 1000 $? I'll need to build more of mine and start selling, could be way cheaper and still make a nice profit, haha)
Yes, I thought so too.

Quote:
Originally Posted by susho View Post
Seems like that. I borrowed my PU sidewall from kiteboard building. I guess Loaded had the same idea around the same time :P
Yes, seems that you and loaded have used same method, I think skis and snowboard uses this technique also to suport impacts, however, seems difficult and expensive, besides that add an extra weight, right?

Another reason to use margins on the edges. Could it be to avoid delamination?

Regards

Last edited by compoforo; 08-24-2013 at 11:58 AM.
compoforo is offline   Reply With Quote
Old 08-24-2013, 01:12 PM   #7
susho

Composites Expert
 
Join Date: Dec 2007
Location: Lemmer, the Netherlands
Posts: 537
Thanks: 10
Thanked 72 Times in 67 Posts



Default

takes about 15 mins and 5 euros on materials, plus extra mould. Not that difficult. costs about a 100 grams. And yes, definitely better on impacts! I throw it around all the time, hitting curbs, etc. The boards with just fibre on the sides would have them exposed (carbon splinters...) and it hides the relatively soft core
I have used red ceder wood on foam cored panels too. Easier to finish, harder then foam, higher shear strength to avoid delamination. But Interior use don't takes the beating a board does, although a wood sidewall around a foamcore board would be a relatively easy, fast and cheap method, again to protect the softer core and prevent delaminating. Probably would help the vibration dampening a bit too
susho is offline   Reply With Quote
Old 08-27-2013, 07:47 AM   #8
riff42

Composites Expert
 
Join Date: Oct 2003
Location: Uni. of Delaware.
Posts: 2,128
Thanks: 5
Thanked 105 Times in 88 Posts



Default

1: yes, avoid delamination. The shear strength of the foam is a lot LESS than interply laminate.
2: you can damage foam easily. It will get dirty, look ugly, and after awhile, it can wear away and you have no foam on the edges.
3: see #1!!!
__________________
---
I want my last words to be:
"Hey, this is fun!"
riff42 is offline   Reply With Quote
Old 08-27-2013, 08:54 AM   #9
compoforo

Member
 
Join Date: Aug 2012
Location: Cantabria
Posts: 111
Thanks: 31
Thanked 10 Times in 6 Posts



Default

Hi Riff42 , I don't explain me clearly,I don't let foam exposed, but I extend it for all surface as possible, I mean this:




Respect delamination, I guess depends largely of fabrication method and the resin used, but I found that when the panel is infused adhesion between the foam and the laminate is even better that between the laminate. Could be?

Regards
compoforo is offline   Reply With Quote
Reply

Bookmarks

Tags
edges, finish, panels, sandwich

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -8. The time now is 09:28 PM.
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

Inactive Reminders By Icora Web Design