35 replies to this topic

[toonces]

Are there plastics that mix together like acrylics, but are less brittle?  Kind of like PVC pipe?  And have a decently long cure time, so one can work with it sort of like resins for fiberglass?

 

 

[Dave McG]

Would epoxy do the job? JB Weld is hard & brittle, but plain two part mixtures are not.

[toonces]

Don't want it to be brittle.

 

And I'm looking at Fiberglas size job.  Like 10-15 square feet.  Want it to be about 1/4" thick.

Edited by toonces, 14 September 2022 - 10:37 PM.

[Dave McG]

https://www.westsyst...epoxy-adhesive/

[Patrick C.]

You want to cast something, and then be able to work it before it sets? There are slow setting epoxies for casting- I imagine that you could pop it out of the mold while still soft and deform it.

[toonces]

You want to cast something, and then be able to work it before it sets? There are slow setting epoxies for casting- I imagine that you could pop it out of the mold while still soft and deform it.

Not necessarily work it, just a long set time because it's not going to be small, and it's likely going to be just me doing it.

 

https://www.westsyst...epoxy-adhesive/

This looks really close, if not it.  In the vein of some of the boat and canoe projects.

[Brian72]

An actual fiberglass kit with the cloth and resin wouldn’t work?

[dondewey]

Epoxies are the obvious answer, but also consider urethanes:

https://www.fibregla...Learning_Center

[BlackBeerd]

Everything you could ever need.

 

https://www.smooth-on.com/

[Hines]

so what is the actual project?

[Dave McG]

Not necessarily work it, just a long set time because it's not going to be small, and it's likely going to be just me doing it.

This looks really close, if not it. In the vein of some of the boat and canoe projects.

West System has several other variations. The G-flex I linked is made to be flexible, and I've seen people use thickened versions of it to mold parts.

[davelew]

Epoxies are the obvious answer, but also consider urethanes:

https://www.fibregla...Learning_Center

 

Yeah, polyurethane was my first thought after epoxy.  It's pretty commonly applied to large projects like floors.

[toonces]

so what is the actual project?

https://www.groundfridge.com/

 

They don't sell in the US, and shipping would kill me.

An actual fiberglass kit with the cloth and resin wouldn’t work?

Don't think it would be strong enough.

Edited by toonces, 15 September 2022 - 01:08 PM.

[SnowMan]

Isn't that just a root cellar? I don't see anything special any that that you can't get by burying your standard big frp tank. They just make it easy

[Hines]

That’s what I was thinking, use large water reservoir and cut to shape.

[Patrick C.]

 and shipping would kill me.

 

 

 

Where have we heard that before? 

[Patrick C.]

You trying to cast the whole thing, or joining sections together?  

[toonces]

With that inner diameter, the volume is ~1650 gallons.  I've yet to find any spherical FRP's that volume.  Even if I did, there's the issue of getting in and out.  Most other underground water tanks tell you to not let the volume get below ~1/3 of the volume, otherwise the weight of the dirt will cause it to collapse.

 

 

You trying to cast the whole thing, or joining sections together?  

Do sections around a bisector of the sphere, along the axis of the stairs.

[dondewey]

Guy I work with put an 8 foot diameter metal culvert underground for his wine cellar. It looked fantastic after he finished it.

[toonces]

Do sections around a bisector of the sphere, along the axis of the stairs.

Similar to this...  With fiberglas, or maybe woven poly like what malt comes in.