New Possible Molding Material

[bamabass]

The stuff is called Hydrogel-Alginate. Mix 3 part water to 1 part powder.

[MTfishingrods]

If I read it right the mold has to be kept in a sealed plastic bag and is only good for a few days.

[bamabass]

Good point there MTfishingrods

Somehow I missed that before

I think ill just stick with the RTV

[K.C.K.]

Alginate is a 1 time mold .. it has incredible detail. we use it for doing nude live casts then pour plaster in it to make a positive..then you can do a silicone negative mold from the positive...this would work great if you wanted to cast a dead fish..

hope this helps

K.C.

[Mattlures]

Alginate works good for cheap fast prototyping

[diemai]

@ bamabass

Never heard of this molding material , that you have described , I am not into molded lures , anyway .

But here is another material , that people might probably be interested in , saw it first time published in a German angling magazine in summer 2001 .

The chief writer of that magazine , also an ardent lure tinkerer , has thought about it on ocassion of some dental surgery .

The molding material is that stuff , that dentists use to make negative prints of jaws and teeth to furnish braces or false teeth .

Anybody , that had gone through sucha procedure knows , that this putty cures within minutes .

Well , I have tried to do the same with a bigger minnow , but my attempt had badly failed , since I obviously had obtained the wrong material or did not mix it well .

So I asked that guy from the magazine(I know him personally)to borrow that very mold pictured here and I cast about 150 blanks with it , and it would still have made up for 150 more .

Astonishing , how this stuff withstands the heat of molten lead .

I have uploaded some jigging spoons made with that mold in the gallery before , named "The Real Thing" in there .

Hope , that the important things are visible on those pics(sorry , don't have a printer/scanner) , the text is in German , anyway .

Greetz:yay: , diemai

[dramone]

if alginate or similar is used as mold material, keep in mind, that not all resins work with a "wet" mold!

Edited December 31, 2008 by dramone

[Vodkaman]

I occasionally use alginate. I sometimes make a cast of a carving. I can usually get two plaster pours before too much degredation occurs. Alginate is really a one shot material.

I am sure I tried it with resin and it dissolved the alginate, so no good.

Dave

[millwood]

Alginate is a great product only in certain conditions. You must maintain a stable field (moisture, temperature, humidity). If you are going to change any of those variables then you had better not use it. As for stability, it is really only there for 24 hours under constant conditions. If you are looking for something more stable then look into PVS or VPS (polyvinyl siloxane). This is what dentists use to make stable impressions that can last a life time. PVS comes in different viscosities so you can let a light body that flows easily or a heavy body that is stiff. Usually a llight body is flowed onto the surface and then followed by a heavy body for the "filler". These do not have to be maintained in a wet field either. Not sure you can get PVS on the open market....I have access to it by trade and it works wonders at craeting duplicates of pour items.

[bamabass]

Welcome To Castaldo/F.E. Knight, Inc.'s web site

Another product worth mentioning.

Seems like it would work great not only for hard baits but also lures requiring lead pouring as it is resistant up to 900 degrees F

Anyone used or heard of this?

[redg8r]

Welcome To Castaldo/F.E. Knight, Inc.'s web site

Anyone used or heard of this?

Ive used Smooth-on's poyo putty..... not very impressed, I prefer the liquid, but it works nice for 1 part molds.

The castaldo temp. tolerance is interesting, however.

Back to Alginate, I get mine on ebay in 1lb bags, pretty cheap, its the dental variety, so it sets up fast (@ 30-45 seconds) & has a nice minty flavor

Like was said above, alginate is only usable as a temporary or intermediate mold material, it's food based (made from Kelp) so it will shrink, dry-out & spoil over time, so if you use it, use it shortly after it cures.

PS, Plaster is about the only material that can be cast in alginate molds, I've tried poly resin and urethane resin. didnt work & given its water based I hope no one's careless enough to try & pour hot plastisol in it

[Vodkaman]

The alginate material is also very soft and so will easily distort under its own weight. So if making a cast of a larger object, it may be necessary to reinforce the mold. I used strips of material (old socks), soaked in PoP mix and laid over the alginate. You can use mod rock, which is a material, pre-impregnated with PoP, but it is more expensive, the socks worked fine.

Dave