6 January 2023
https://www.facebook.com/groups/paipobe ... 086250080/
Facebook posts: Matt Pierce
-
bgreen
- Big Wave Charger
- Posts: 1395
- Joined: Fri Aug 19, 2011 5:17 pm
- City: Brisbane
- State or Province: Qld
- Country: Oz
- Contact:
Re: Facebook posts: Matt Pierce
John Dixson.
Has anyone used XPS closed cell foam and did you add a stringer.
https://www.facebook.com/groups/paipobe ... 184895080/
Bill Wurts
I have. But switched to XLPE for prototyping shortly after to eliminate glassing. So the XPS board has only been out once (42-inches long, less flex stress). Foam density, surface prep, glassing schedule and keeping the board out of heat and direct sun are critical.
Matt Pierce
I plan on doing a paipo build with it . Gassing off has always been a issue with xps. I remember reading about it's use in surfboards on swaylocks 20 years ago. I could never find it in California but it's everywhere here in idaho. I have left some out in the rain for a few months with seemingly zero water absorption. I might just gorilla glue some thin ply on top, shape the bottom and paint with exterior latex paint and see how it goes. Also want to try poor Man's fiberglass for surf application. Canvas drop cloth, titebond 2 wood glue and saturate with exterior paint. Been a thing on the boat building industry for over 100 years. I'm buildings a truck camper now and it's been in the snow/rain for a few months with no leaks
Bill Wurts
Matt Pierce XPS is “closed cell“ foam. Virtually no water absorption. If it doesn’t absorb water, it can’t off-gas. The problem is the very small closed cells. When sanded, there is minimal open cell surface — minimal epoxy resin penetration — so mechanical bonding is poor, especially if XPS surface has not been properly prepped. The most common mistake is using low-density XPS housing insulation (min. Compressive strength = 14 psi). The expansion and contraction of heating and cooling accelerates the development of delams from pressure dings. XPS for Surfcraft should have a min. Compressive strength of 25 psi (40 or 60 is better). All XPS needs proper surface prep.
Matt Pierce
Bill Wurts what some foamie builders solution is. I just finished with 40 grit and so far no issues. The one panel I have some bubbling was my first where I went light on the glue. After that I learned and panels came out perfectly . I made a few kneeboards with the crappy home Depot eps . Probably 3/4 to 1 lb eps . They would last a year or 2 . If dinged they soaked up ocean like a sponge and never dried out. Terrible choice in material but I could make a blank for 10 bucks and had connections to get deals on epoxy.
Alan Bruce
Not worth the aggravation. Just use eps - easier to shape & lighter. May as well use PU than XPS
Geoff Archdeacon
Why would u need obe so light???
Has anyone used XPS closed cell foam and did you add a stringer.
https://www.facebook.com/groups/paipobe ... 184895080/
Bill Wurts
I have. But switched to XLPE for prototyping shortly after to eliminate glassing. So the XPS board has only been out once (42-inches long, less flex stress). Foam density, surface prep, glassing schedule and keeping the board out of heat and direct sun are critical.
Matt Pierce
I plan on doing a paipo build with it . Gassing off has always been a issue with xps. I remember reading about it's use in surfboards on swaylocks 20 years ago. I could never find it in California but it's everywhere here in idaho. I have left some out in the rain for a few months with seemingly zero water absorption. I might just gorilla glue some thin ply on top, shape the bottom and paint with exterior latex paint and see how it goes. Also want to try poor Man's fiberglass for surf application. Canvas drop cloth, titebond 2 wood glue and saturate with exterior paint. Been a thing on the boat building industry for over 100 years. I'm buildings a truck camper now and it's been in the snow/rain for a few months with no leaks
Bill Wurts
Matt Pierce XPS is “closed cell“ foam. Virtually no water absorption. If it doesn’t absorb water, it can’t off-gas. The problem is the very small closed cells. When sanded, there is minimal open cell surface — minimal epoxy resin penetration — so mechanical bonding is poor, especially if XPS surface has not been properly prepped. The most common mistake is using low-density XPS housing insulation (min. Compressive strength = 14 psi). The expansion and contraction of heating and cooling accelerates the development of delams from pressure dings. XPS for Surfcraft should have a min. Compressive strength of 25 psi (40 or 60 is better). All XPS needs proper surface prep.
Matt Pierce
Bill Wurts what some foamie builders solution is. I just finished with 40 grit and so far no issues. The one panel I have some bubbling was my first where I went light on the glue. After that I learned and panels came out perfectly . I made a few kneeboards with the crappy home Depot eps . Probably 3/4 to 1 lb eps . They would last a year or 2 . If dinged they soaked up ocean like a sponge and never dried out. Terrible choice in material but I could make a blank for 10 bucks and had connections to get deals on epoxy.
Alan Bruce
Not worth the aggravation. Just use eps - easier to shape & lighter. May as well use PU than XPS
Geoff Archdeacon
Why would u need obe so light???
Who is online
Users browsing this forum: No registered users and 3 guests