Before you began, I was sure a surface application wouldn't make much difference in breakability. You have to add something to the plaster mix itself. Without evidence, i would think the Titebond or Durhams might be the best choices. I might also try Weldbond glue. I used to teach art in public schools. At the end of each year, I would haul out boxes of dead pens & markers, scrap pieces of wood from the wood shop, styrofoam "peanuts", cardboard, empty plastic container, etc. to create "junk sculptures" glued with Weldbond. The first year, a few students didn't take their sculptures home. I decided to break them apart so the pieces could be used the next year, But Weldbonded items were impossible to break apart, even with a hammer. So I would guess some mixed with plaster would increase its strength. It might also impede staining since the plaster would probably be less porous. Again, these are assumptions made from my own experience with hundreds of art materials I've used in my 79 years..
The Durhams water putty when mixed correctly ( the consistency of glue/pancake batter) will harden to the strength almost equal of Bondo. For these small parts, I would use nothing else. Look no further. A word of caution, Bondo is actually easier to sand.
I use this all the time for other materials but I would imagine glass fibers would massively increase durability. But it definitely depends on the mold or project.
I never worked with Plaster of Paris (or any other kind of plaster) before, but I recently bought some costume props from an organisation. The helmets have some damages, and I want to repair them. It looks like the helmets are made of, which I assume, cardboard (or paper machee) and then covered in a thin layer of plaster. What would you recommend I use for those damaged parts for regularly wearing the helmets (inside and outside, with posibility of rain)? Just normal PoP? Seeing that you use water based coloring (and water to make it), I assume rain won't do much harm? It's obviously not the intention to drop the helmets, or use them in combat simulation, so that's why I think they used plaster in the 1st place Also, I'm going to spray paint & then varnish (or maybe lacquer?) when the helmets are finished to my liking
Probably too late for your needs. I might try using one of the following: Outdoor strength spackling. Once dry it can be painted with exterior water-based paint. It is water resistant, so would probably withstand sweat and or rain. I would seal the pieces with something like Minwax polyurethane (outdoor/indoor, water & fade resistant) before adding the spackling and then as a sealant after painting. I also saw a video of someone using flour, white glue, baking soda and vinegar in a similar way. Unfortunately she didn't include amounts. The vinegar is to prevent the mixture from getting moldy before it dries, which might take several days. I plan to try several mixtures of that flour clay on small items to create my own recipe. Look for videos of homemade air-dry clay. You can add paint to color it ahead of time or paint it after., Pieces can be glued on with Elmer's or wood glue. One disadvantage is that the pieces do shrink a bit while drying, so they won''t work with everything. For example, if you were to make a bowl with it, you could press it inside of an existing bowl to create the shape. As it dries it will get smaller inside of the bowl. But if you put it on the outside of a bowl to create the shape, as it shrinks, it will probably break. I've also use modeling paste to fill in missing pieces or breakage. In small areas, it dries in an hour or so. For large areas it might take a couple of days.
I watched the movie until the end and I have two conclusions. It is enough to change the type of plaster, i.e. use dental plasters of class 4 or 5, they are slightly more expensive, but have very high mechanical strength. The second option is to add dispersed fibers to the plaster of Paris, they will strengthen the interior. Plaster of Paris has poor early strength and is therefore brittle. These are two options that will significantly improve its durability :) PS. Epoxy resin can be diluted with cresyl glycidyl ether and or benzyl alcohol :) Greetings from Poland :)
Any other suggestions? You demonstrated exactly what I am searching for! I have premade plaster ($Tree Christmas) orniments. Several broke on the drive home. Now I need to safely transport & store the unused ones for painting next year! 😮 Also, I'd like to strengthen the painted ones. I am not going to cast multiple orniments for 8 grandchildren & their parents plus the grand parents. I'm grateful to have found cute, affordable, premade orniments, although fradgile. Wish I'd thought of looking this up sooner. I'm grateful to not waste my time on these options. I'm going to experiment with the broken orniments. Maybe a paintable base acrylic primer would work. Thanks again! Good topic, demonstration, explinations, narrative, and summeries.
🔺I expected you to add the product into the PofP mix. Thats the method for gaining a successful greater tolerance. 🔹Ideally you Stain first, followed by the sealer/Polyeurophine. 🔹Over a sealer it is recommended that one use "Chalk Paint", other paints won't adhere, either at all 9r well, over sealer. Thanks
I know Im 2 yrs late...but I wonder how Mod Podge would have been? ANd there are various types of mod podge to use, but Id just try the matte mod podge. Id also paint it first, then use the MP. It might help with scratches and seal it, but I dont think itd help for breakage. I have mixed Mod Podge in with my paint and then painted the plaster of paris mold (fake food, I made fake Ice Cream sandwiches with PoP, lol!)
I've sometimes seen yt movies where they stick plaster to a ceiling and then move over it with a kind of shaped profile to make a decorative moulding. Do you know what they could have been using for this? I think they were talking about plaster, but that is much to liquid to stick to someting... Thnx
mix fine "aquarium sand" or any other fine sand into the plaster of paris mixture up to 1:1 mix ration to improve strength and ridigity. For bigger pieces use steel wool or small metal mesh as reinforcement.
can you see the sand in the mix? I make fake food with plaster of paris and had a problem with big pieces breaking. I tried using foam clay instead, but its just too expensive and also doesnt looks as good as the plaster of paris bc foam clay can warp super easily. I like the smooth surface of PoP, though, when I can get it out of the mold without breaking anyway, lol! So I wonder how much the fine sand would affect that
@@Em22-wtf You mean if you can see the single sand pieces after you pull it out ? It will change it´s color but if you paint it you won´t see it. What you can do to improve the surface quality is you can brush a very thin layer of plaster on the outer surface before you pour to make sure you have captured every detail. Try it out and see if it´s useful for you .
Add a light dusting of corn starch to the mould first before clay or PoP, just brush on powder with artist brush, if too much goes into mould simply blow out. Stops the clay or PoP sticking & breaking taking it out of the silicone mould…
PU products is not good when you want to have absorbent nature, that's my experience, several people as well mentioned it regular white wood glue(not the water proof grade, but an interior one should do the trick)
Wait, air dry clay? You have my full attention! Do you have a recipe you recommend? I've been using calcium carbonate for making chalk paint but POP is much cheaper, thank you for the tip!
Correct, and depending on type of glue and amount, it can really be an added value towards prevent breakage. It is of little value to try to strengthen by adding, an after the fact, product.
io lavoro spesso con plaster of paris e ti garantisco che nessun prodotto dato all'esterno evita la rottura qualunque sostanza non agisce da rafforzante, quindi io aggiungo la colla x falegname dentro il gesso e ti posso garantire che è strong
You wonderful human, thank you for this tip! You sent me down a rabbit hole for an entire night and I learned that this is similar to a product marketed to crafters called Jesmonite that is wildly expensive and difficult to source in the US. I was able to find the acrylic fortifier at Home Depot. From what what I read it's a complete replacement for water, as you mentioned but @tycoon891 do you still look for the same clues as dissolving in water (dry lake bed effect, mountain of plaster, quick vs slow absorption) or does it behave differently?
I have perfect casting and I made little angels in a broke easy I read online that you can add glue to the water before you add plaster of Paris and it will make it stronger I will try this technique
Yeah, I just wanted to experiment with the things I've already cast. I will have to try adding things to the mix. I've seen both things like wool and glue to both increase the durability. So you think PVA or wood glue would be best?
If you mix that titebond with your water before adding the dry plaster, I believe you'll get the results you're looking for. The wood glue is the best for the job considering the cost oft he epoxy resin, and it's the acrylic that does it. Once my pieces are dried (I just make planters,) I mix some wood glue and water, sometimes a tiny bit more plaster depending on what I'm after, and brush it over the whole thing. LIke you said, it sponges it all up AND, believe it or not, it'll allow you to burnish your piece better than just the glue/plaster mixture. Gives it almost a Venetian plaster look. ;)
Tried mixin cola and water before adding the gypsum and the result is shit: The Cola doesn't help the Gypsum to soak and to agluttinate into a single structure properly.
@@josephbarth2714 It does. I don't remember everything I read on the subject after I figured it out, but it definitely strengthens the plaster. I still have the result of a test pour I did two years or so ago that, by all rights, should have been dust by now.. but it's still strong as ever and still shiny af. Sounds like bs, but check it out for yourself. for 2 cups of water, I'll add in 1/4 cup of glue, give it a good stir and then add plaster as usual. Nothing else about he process changes.
@@fromtheroots4003 regular cement that is sold at building supply stores. Make sure that it is cement and not concrete or mortar. The cement needs to be cement dust/powder with no rocks or aggregate in it Remember no concrete.
I've tried this and it seems my pieces ended up brittle, then I looked into it and the articles I read said cement powder and plaster shouldn't be mixed. But I will give it another go and see what happens. Thank you!
Could you please put a seizure warning with the flashing in the screen of media offline, I started to become ill and was unable to finish video due to flashing.
As you should know by now with other comments, you are suppose to add the glue within the mixer of plaster and some add in the acrylic paint in the mixer as well for desired colors in mixer.
I suppose the thought was these were things that could be done to existing casts. I'll definitely have to try adding hardeners to the plaster, though I'm not sure I would use my nicest molds when adding glue and things!
@@warscapestudios it doesn’t hurt Molds one bit. I’ve added all different mixtures to silicone molds. Put cornstarch first into mold for best release. Mix the pop into glue water mixture or whatever mixture. . I’ve added all different mixtures to my most expensive molds and they’re fine.
Its really annoying that you did your tests and watered down half the things. If you would have cleaned off the molds between the rock it probably wouldnt break the rocks as easily. For the ones you cant paint over the coatings.. then why wouldnt you paint and stain them first? I don’t understand how sealing them before you paint or stain them would make sense. However, i do appreciate the details you talk about with each thing and that you tested multiple things. Just wish you would have mixed things properly before dismissing the product saying it didnt work when it wasnt mixed correctly to begin with.
Sorry you didn't like the video. I suppose I wasn't trying to dismiss anything, just had a process and followed it for each product. I'll definitely try adding things as part of the casting process, possibly showing the results in a future video!
Seems like maybe you could mix the different types of hardners to the plaster while making the rocks & it might make them harder. You should try it & make a video like this one.
If I wanted to make the PoP indestructible could I just mix it with something other than water in the first place? For example just make it a PoP polyurethane mixture and put it straight into the mold that way?
Mix 2 part epoxy and add your pop or Durhams Water Putty to it, rather than the water you'd normally add. Almost unbreakable, and water proof. You could cast using POP, then use the epoxy mix as a Coating you'd brush on. FYI, you thin epoxy with a small bit of rubbing alcohol or even just warm the mix with a hairdryer and it's much thinner.
on those flat molds I press strips of gauze or cotton in the back to help hold them together when I take them out. I also adding some glue to the water to help make them stronger
This is weird. I looked into this years ago, and they were adding the items to the mix, not top coating to make it stronger. Top coating doesn't seem effective. I actually tried the school glue and it worked for me. I mixed it with the plaster and then poured and cured. I don't remember what the ratio was now.
Great info! Thanks for sharing. I would suggest staining your rocks before applying the surface protectors, like Polyurethane etc. Just a suggestion. Have a better day!
does this trick works? i recently started using PoP and it breaks easily during sanding, and the method from the video doesn't seem so cost effective unfortunately
