How do you fill a hollow walleye reproduction? need help

Why do you need to fill them? Is there a block for attaching to the wall? If It were me I would glue in a block and then fill with expanding 2 part foam, if I felt I needed to fill them.

 

Filling with foam, you are at risk of blowing the cast apart.

 

You can use expanding foam to provide some backing but as mentioned you need to be careful as it can blow out a mold if too much is used. BUT, I don't use expanding foam for another reason - I'm cheap - lol! Usually, foam in a can is a one time use. So, I end up wasting most of a can (or find holes or cracks around my house to fill as I never use much on a fish.) All you need is something for your epoxies to grab onto or prevent from falling into the mold. For eye setting I like to simply shove a bunch of old newspaper in until it's kind've tight. For the gill area you can cut and glue fitted cardboard down for a foundation to build Apoxie Sculpt or the likes on top and around. Just make sure some of it is adhering to the mold too when you lay it down and not just on the cardboard so you get good adhesion. And lay your epoxies down in layers so the weight of the epoxies doesn't collapse the cardboard and/or newspaper inside...

 

I use 2 part foam. Just a bit if its just to set eyes, more if it is an open gill that needs filled. I will tape off the open gills with foil tape, pour through one of the eyes. You are only using enough foam to fill the head area, not the whole fish. I then remove the foil tape and carve my gills out of the foam that is left. You can coat your gills with some resin, epoxy, or plastic and paint. Works pretty slick.

 

Cole - what kind of two part foam do you use if you don't mind sharing? That sounds like the way to go as you don't waste a can of the Great Stuff for only a small amount needed and probably more supportive than the method I've been using. Newspaper is fine for setting eyes, but the gill area not so much. For me it only happens once in a while when I order a blank from an obscure source. But nonetheless I have seen a need for foam usage in the shop on other occasions as well. Does this two part product have a long shelf life?

 

I just use 3lb polyurethane foam. You can get a 2 quart kit from old barn for $30. It has a shelf life of about a year, but for this application it would work if it was older than that. Much older probably.

https://www.oldbarninc.com/products/3-two-part-polyurethane-foam?variant=41790016327

 

Thanks Cole. I am doing more replicas these days and this is a product I probably should invest in. Sold out for now, but I'll check back. Thanks.

 

You should be able to get the same thing from Matuskas.

 

The only thing to be aware of when using the expanding foam in a can is the fact that it does and will break down over time. As long as you have covered the foam with an epoxy, it should however not cause you any troubles. I would make sure to also get a good epoxy base behind the eye orbit for this reason.

 

foam in a can is not just one time use just remove straw and clean nozzle and straw...and the foam will only break down in sunlight... a shot of plain water in a syringe wil cure the "wet" foam