How To mix Plaster of Paris - For longer working time.

This method will give you longer working time with your plaster of paris before it hardens.
(Drywall mud does not work with this technique)
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[@francinetoni268]

I wish I had seen your video before I wasted 3 lbs of plaster of Paris trying to get it right! Thanks so much!

[@denaekrisman2588]

Substitute about 1/8 cup of water for white distilled vinegar will extend the hardening process a good amount of time. The more vinegar, the longer u have to work with👍

[@calexiou69]

Thank you thank you thank you ... So simple and so effective.

[@jmac4952]

I watched your video. Thanks for the advice. Also I added 1 tsp of lemon juice per liter to slow the cure by about 20 minutes. This gave me time to vibrate any air bubbles out of my casting. I also put on rubber gloves and slowly mixed with my fingers. That way I could feel any clumps and press them through my fingers to get rid of them. It all turned out perfect.

[@Kimosabe-]

SO HELPFUL! "We're not making scrambled eggs"... This solved a mystery for me. My plaster mix hardened too fast for me to fix my wall cracks. THANK YOU!

[@stevemichigan541]

Well did what you showed on vid. Took 40 minutes to set. Worked great. Thanks. First time using plaster of Paris to make wolf copy from a original.

[@eileenschuller5309]

Thank you - novice at working with PoP so this was very useful.

[@susanoosthuizen9338]

My word I need to send you a gift to say thanks for this great video! You have saved my bacon for sure so THANK you Sir very much! Great great tip!

[@davidcurtis5398]

Couple of things I do. I put ice into the water while getting things together. I also use a little vinegar in the water and this holds up the curing process. I sift the plaster into the water and this seems to make it very easy to mix without bubbles. I have a box filled with kitty litter (we have a cat) and this molds to the bottom of the mold and keeps it level. I use a 16 X 20 photographer's tray for this (I just happen to be a retired photographer). I spent $5 on a bag of bark - separated it into good chunks - threw away the junk - spent $32 on latex and now have about 25 different molds to use.

[@davidcurtis5398]

I forgot to tell you all that this process can be used to make rocks on any scale. I especially like the "N" scale type rock faces that I use in the background for effect.

[@phyllisallen5144]

David Curtis I

[@jess65963]

Jolly good idea? May I borrow it?😊 I will definitely try this.

[@loft4me]

Simple enough procedure, yet with sound techniques that build up a good demonstration for extending the working time of plaster. Thank you. I've been working with the brand Fixall, for casting small rocks for dioramas, but now have the need to fashion a dog animal in the "O" scale for a current build, and have not seen anything pre-packaged that's suitable, yet. Hence the thought that maybe I can carve one out of wood or plaster. Again, thanks for your clip.

[@alwayslivecreatively9069]

Thank you so much for this tutorial. I was doing it backwards. Couldn't figure out why it was hardening. Now I know

[@bill2339]

Well done! I finally found a tutorial that provided the specifics I need to continue my project with enough confidence to expect a successful outcome. Thanks.

[@DGModelworks]

Thanks Bill! I'm very happy this video provided some help. Good luck with your projects! ~Deryk

[@angelboyd5723]

Fantastic video! Thank you so much for the tips. I'm also a bit new to working with plaster, but I'll definitely keep this in mind. Thanks again!

[@DGModelworks]

Thank you Angel! I hope I could give you some good tips! Deryk

[@jessejohnson159]

It's my opinion, those that don't learn how to do something right the first time, "because it's so easy", end up learning the hard way about their errors! (That's why I did the search I did!) Thank you Sir!

[@DGModelworks]

Well said! And thank you very much. This is an old video and my video techniques have improved since then. But it still gets the point across.

[@quotinafloyd4140]

I needed this entire video. You broke it down just like I need it. Thanks!

[@DGModelworks]

Glad it was helpful!

[@sobizzr]

Great tutorial. Thanks heaps for this. My first attempt to make fishing sinker mold was a disaster. This clarifies a lot . Thanks.

[@DGModelworks]

Thanks!! Glad I could help out!! Good luck with your sinkers! Deryk

[@jimh2061]

I've been using this now for a while. I repair drywall with it and it works fantastic as a prefill for larger joints or holes. I mix it gently but I need a consistency that will stick to a drywall knife to put on ceilings. I've skimmed out patches with this stuff. It takes practice to get used to using this. I used to use a floor patch but this stuff really sets up and gets good and hard. I've used the easy 20 and it takes an hour or more to dry. 20 min is working time. In contrast the plaster working time is about 3 or 4 min.

[@faizakhalid1331]

Hi Derec! I don’t have words to thank you for these tips! You have literally made my life easy! I have been working with plaster for quite sometime and always had this issue of plaster drying too quickly, today I followed you and Oh my GOD! I am flabbergasted! Thanks a milllioooonnnn timmmessssss ♥️♥️♥️ God bless you!!!!

[@DGModelworks]

Great to hear!

[@disturbed1954]

I wished I had watched this video before trying to make my tunnel liners as they turned out terrible but will give it another shot to day like you have shown here. I also found out best way to hold your rock molds is take old USPS box that you got in from ebay and cut the top out leaving all your pink peanuts inside and set your molds on top of them and they will support your molds while you pour your plaster into them, at leat they worked for me. Thanks for sharing Deryk!

[@DGModelworks]

Thanks David! Great idea with the USPS box. I will have to do that. Looks like we helped each other out!

[@cindykiefnerthecoppertorch7789]

Thank you so much! Cold water made all the difference!

[@sobizzr]

this video is tops on tricks. you can even answer a phone call and chat and get back at the mixture with no probs. no stirring and cold water tricks, great tips Deryk. very much appreciated.

[@DGModelworks]

Thanks so much! Glad I could help out! Little tricks can make a Big difference! Deryk

[@lindastowars7346]

LOL - I JUST GOT A CONTAINER OF PLASTER OF PARIS AND WILL BE TRYING THIS TOMORROW

[@delvis7842]

This was very helpful! Thanks for sharing!

[@marisolvelez9076]

I wanna thank you thank god for people like you who teach sheesh i really screwed up my project i mixed it and went to the bathroom when i came back it was hard like seament

[@alisonmary1443]

I originally started looking for info on what is stronger than plaster of paris. I find it cracks very easy when doing fine work that needs a wee file at the edges, but I need to use the fine work powder. However thanks for this, really enjoyed the video also thanks for all comments with more handy hints, this has been a great school day for an over 50. I usually leave the plaster to dry in the container and just crack off into the bin and the mixing utensils I immediately wipe with baby wipes or sorts and bin them. Back to my original search now.

[@slaquehogue]

Metakaolin clay with portland cement

[@deeznuts_808]

I wish I watched this before I wasted my plaster. It hardened up too fast and I didn't even accomplish what I wNted to make. Thank you for this tutorial,very informative.

[@DGModelworks]

Thank you...Hopefully it works better for you next time.

[@theanonymous8069]

@@DGModelworks umm hello...greetings from Malaysia...i wanna ask that...how much time for the plaster of paris to hardened for carving...or...when can i carve the plaster...till it hardened or when it still moist...

[@clementramon8589]

Cool video. Wondered what I was doing wrong. Thank you...

[@efitter7]

Very helpful Deryk! I will defiantly use what I've learned. Thanks for sharing.

[@sam111880]

Excellent video the big thing i really didn't think about is not putting it down your sink / drain system. If i didn't see this i might have not thought of this. That was major key element always wash it out side thanks for that one :)

[@judithpool8177]

Thank you for shoqing so clearly how to do the mixing process. I Just blew my asignment and was pretty diappointment. Now Thanks to you it will go right the next time

[@DGModelworks]

You are so welcome!

[@purnimakumar6163]

Omgosh, I'm so glad I watched this,after making my first hand shape,I wasted so much after that, thanks for this video

[@DGModelworks]

Thank you, I'm glad it provided some help!

[@dacuzzz]

awesome "how to" deryk.. thanks for sharing vinny

[@tamasmarcuis4455]

This is the saturation method. Soak method used for figures place the plaster in a bowl first followed by carefully pouring the water in and leaving it to completely soak into the plaster. You only then give it a slow smooth stir. It creates a much more watery mix with less trapped air. I think it is better for molding. Worth a try.

[@ShakespeareCafe]

Calcium sulfate is plaster of paris and setting type drywall compound. It hardens via hydration reaction hydration of anhydrous calcium sulfate: EXOTHERMIC= gives off heat CaSO4(s) + 2 H2O(g) CaSO4·2H2O(s)

[@loumentor9354]

thanks buddy for this video. i utilized this tutorial for a project i'm making tonight. very informative.

[@DGModelworks]

Thanks! Glad it helped you out.

[@ThaMaskRapper]

I did one cup of water and two cups of the plaster of Paris and it worked good it came out good I didn't know what to expect cuz it's the first time I'm doing it thanks for the video , but me using it is like so watery I like to dry mix already made.

[@phera5713]

That was a great tutorial! Thank you! I learned a ton.. The instructions don't mention stirring slowly.

[@DGModelworks]

I'm so glad it helped you! I was new to making videos during this time. It's not my best work, hahaha. Thanks again! Deryk

[@adamdellow3306]

Thank you for posting this video, I greatly appreciate the service.

[@DGModelworks]

You are very welcome! I hope it helped out!

[@adamdellow3306]

I tried it last night because I did my operation away from my studio so I could get it documented for my own purposes. But yeah, ran into volume problems with my plaster, and because I was making a two part mold, I ran into some clay leveling and partition problems. Today I think I have a really good idea of how to do this right.

[@sallytucker6176]

Thank you for this video, I have wasted some much plaster. Wishing I had found this faster.

[@randygelp8309]

Deryk , WHAM ! Poop , I thought I knew , but watched , to my suprise I didn't know anything , well maybe opening the bag of plaster . Thanks . I have seen your Walters mine kit on other websites and each time I see it the better it looks . Now it is over the top of the chart LOL . Randy

[@fbrailroad4628]

Some good info. Thanks for sharing, David

[@DGModelworks]

Thank you!

[@creativeline03]

Very helpful video , thanks

[@dbroadwayvfx]

Thanks so much for this video. I've clearly been mixing plaster wrong. I'll use your method tomorrow, and hopefully it'll all go smoothly.

[@andrewjackson3761]

I don't understand why people want it thick . It can crack if it's thick you can trap air bubbles and it some times won't fill details . I know rocks sent that important but follow instructions runny is good air bubbles will rise you can stir it in the mould . It might be slightly longer to set but your video was about extending time . Just try it at 2:1

[@ruthselden8637]

Very good and informative video - I learned a lot.

[@DGModelworks]

Glad it was helpful!

[@rogerroger5585]

First time I tried mixing plaster of paris it ended in disaster. That's what brought me to your video. I then watched your video during my second attempt...success. Thank you so much for your video.

[@DGModelworks]

Thanks so much for the kind comment! I am so glad I could help you out! I also got frustrated mixing plaster of paris till I found this method. Now I am not intimidated to do it anymore. Enjoy your new found talent! Deryk

[@mariuskruger9894]

Thank you very much. Marius. South Africa

[@JamesDoylesGarage]

Awesome thank you to everyone that contributed :P

[@nickwoo2]

Thanks I was adding water to the plaster and it was just a lumpy mess thank you

[@robviolin1]

Helpful, thanks. 👍

[@dackdoid]

Today was the first time I used Plaster of Paris since primary school years. I had no idea what I was doing, I added the water to the plaster in a jar then shook the hell out of it lol. Thanks for the video, now I know what I really should have done.

[@DGModelworks]

Thanks! It's hard to believe something as simple as plaster of paris, really has some tricks to it. LOL

[@dackdoid]

***** My first attempt 5 days later & it set like watery chalk. This time I "think" I got closer to doing it like you said, but it seemed kinda watery still so at the last minute I added some more plaster. I then started mixing, damn it set really quick, however I got done what I needed to & it appears this time it will set properly. This really does take getting the hang of it, its not as easy as some people may think.

[@DGModelworks]

I have found that 2 parts plaster to 1 part water works really well. Keep adding the plaster to the water till you have an even layer on top that doesn't soak up anymore (might take slightly more than 2 to 1 ratio). Then start your slow stir. That should make a good consistency for rock molds. If you get it down where you don't have to add more after your start stirring you will avoid lumps. Let me know how you make out next time.

[@KU4PC]

Wait! I thought I was doing it right!! HA! ,cool vid Deryk.

[@FishplateFilms]

Great tips Deryk, I've got some moulds on order so I'll be trying this soon! Cheers Gregg.

[@calexiou69]

VINEGAR as mentioned by Danae is the solution. A little tiny bit of vinegar and problem solved! Why isn't anybody talking about it. It took me so long to find out and it is so simple. Set time extended a lot !

[@coolbluesky4078]

this is so useful, thank youu!! i let u know if turns out great hehe

[@richardmcnally2056]

Excellent. Thank you!

[@DGModelworks]

You're very welcome!

[@swayzlazer9323]

I tried this to help make the plaster stay workable for longer but the cold does not help plaster hardens by chemical reaction use citric acid to make it workable for longer it actually works :) chemistry is the key :)

[@davidcurtis5398]

Cold water works for me.

[@davidcurtis5398]

ALSO 1 TSP OF WHITE VINEGAR PER FULL CUP OF WATER SLOWS THE CURING TIME A LOT. TO MUCH WILL REALLY SCREW UP THE MIX. SPEAKING FROM EXPERIENCE ANAIN.

[@ogretowman8695]

That helped in many ways ! I've always whipped it ! Thanks a lot !

[@donaldmoore8920]

Awesome how to video

[@cynthiacarr3294]

Great video ‼💯

[@DGModelworks]

Thanks 💯

[@FISHBREATHH]

Great info

[@pamlooman8045]

Thank. You.. appreciate the info..

[@nickturner3654]

Thanks so helpful

[@DGModelworks]

Glad it helped

[@JOEGGGJOE]

I used plaster of paris once. i poured water in the plaster. it was a pain. great tip. i actually use spackle in a bucket. takes longer to dry but sands quickly. i guess it all depends what your project is. thanks for the tip. joe

[@ebeezification128]

I put my mixing container in a larger container filled with ice. It keeps it very cold and it slows the cure rate significantly for me.

[@morganhemingway817]

if you make a little sand box and bury your mold part ways in it: that will help level and hold the mold still

[@rhapsodyhooks6641]

Good info thanks. Have you tried using concrete adhesive to your water mix?

[@ExtremeRC13]

Definitely the best way thank you so much you got a subscriber for this viedo

[@DGModelworks]

Glad it helped

[@ExtremeRC13]

@@DGModelworks this is the only way I mix my plaster now thank you so much I was going through plaster like crazy

[@sawabahmad2708]

nice job

[@rondelaspooner9719]

tHANK YOUUUUU

[@markettabryant8826]

thanks for sharing

[@DGModelworks]

My pleasure

[@tushae88]

Thanks for posting and your right this is a mess to work with. I am desperately trying to make a project and it either too thin and cracks or gets too hard to work with. Im thinking about using flour and water and calling it a DAY!

[@VozUnjida7]

Thank you very much for your advices on how to use plaster of Paris, I’m a beginner using this material and very interested in learning more Thank you

[@NicksCollectableCreations]

Nice video! I am a bit of an impatient person so i just poor, add water and stir :P then RUN to the layout lol I just do small amounts, and add more water / stir and just do it in parts so I can see how things are looking as I go. But I i have found that the dried up plaster at the bottom of the bowl, breaks up nicely into rocks. Woodland Scenics has a video where they pour plaster into a bowl, add water and let i soak down for a few minutes, then stir before use.

[@DGModelworks]

Thanks Nick! While there are many ways to mix plaster of paris, I found this way worked best for me. I say do whatever works for you. Deryk

[@snafu3714]

That's the right way I hope other will try

[@DGModelworks]

Thanks John!

[@pLaIrVaIdNoGx]

Whip it, whip it good!!!

[@ellcajon]

Thank you for reminding me not to rinse/wash that batter mixture into my sink,!

[@HilaryBravo]

and you might want to wear a mask when handling Plaster of Paris in its dry state good tip!

[@davidcurtis5398]

+Hilary Bravo WHY?????????

[@shawntyler2928]

+David Curtis so you don't die from lung cancer. any particulate, any dust you breathe into your lungs can stay there...and cause problems such as emphysema or cancer...don't breathe dust breathe air...

[@bobbisdesigns9399]

have a box or pan with dried beans to place the molds in so they will set level

[@stevesteve2586]

Adding one cup of milk will give you about 3 hours of lasting soft mud

[@davidcurtis5398]

Really????? I will have to try this. Do you need a full cup of milk and what kind - 2% - 1% ???

[@stevesteve2586]

Hi David One litter of plaster and one tea cup [ full ] of any milk will do . [ I have no idea about the cold weather .] The Lemons works as well but not as good as milk. You can try with Lemon powder

[@davidcurtis5398]

+Steve Steve I use 2 tablespoons of white vinegar to 2 cups of water and I get abut 40 minutes of working time until the plaster gets to the point that I can not work it any more. Plus I keep a gallon jug of water (drink a lot of ice water) in the refrigerator so I don't need to use ice anymore.

[@azzym312]

+Steve Steve I have used Gum Arabica ( dissolved in water) Works very well and the casts are very hard too, not brittle.

[@akualezlihope7301]

Thanks! Just what I'm looking for!

[@devbachu7072]

I want to start making little stuff for the home bro

[@randygelp8309]

Unrelated ,,,What are your plans for the original layout ? As you stated , the turns are too tight for your larger locos and your new layout ideas have changed . Have you considered tearing down the old section and rebuild it with larger curvs and more switching ? Randy

[@cyrenefaithonda360]

Wasted 10kg today. Thank you for the video.

[@graceleong2548]

Hey, just wanted to ask if 'Pottery Plaster' is the same as plaster of paris. the instructions on the packaging say exactly the same thing as you're saying and is what I did but it is hardening quickly anyway! Please help!

[@oliverizzard8751]

5:54 amen to that. How does room temperature affect it? I live in hot humid country but usually have the AC on (which also dries the air). I'm not experienced enough yet to know if best keep windows open and let in the hit humid air or turn on AC hard before I do this.

[@DGModelworks]

I'm really not sure.

[@rickm1233]

I was way off. Thank you, Sir!

[@DGModelworks]

You are very welcome!

[@wykedinsanity]

turkey tray with oil dry or kitty litter , i spilled a few molds lately lmao, a big mess

[@nicolecrystal6765]

you should make a baking video

[@MaddyHatesMath]

Putting your mold in sand gives it some support.

[@davidcurtis5398]

Kitty liter works well to.

[@DGModelworks]

+MaddyHatesMath Thanks! You are absolutely correct.

[@LB-pg3no]

I never put my mold in sand, in fact i bleach out the mold so it doesnt spread in the sand! The black mold is the worse and using a strong bleach solution will help! Next ti e you put ypur mold in sand be very cautious, the sporex of tbe mold can spread!!! Lmfao!!!!!

[@devbachu7072]

My first time bro

[@shaungreen7879]

Great thanks. Dos it turn out the moulds ok without breaking 👌

[@DGModelworks]

Yes it does

[@shaynelahmed6323]

Hi. Thanks for the video. I substitute interior paint for water and it gives me 20-30 mins working time. For 2-3 hours working time I add D19. I need help-a diy formula for artexing an interiority Wall.

[@gamingpro00000]

I used oil and some time glue but it doesn't stop quick harder

[@geraldtruesdell9930]

my brother, dad and I put our hand prints in concrete at our old house back in 2001 when he extended the driveway. i want to make a plaster mold of them since i cant take a piece of concrete slab of course. DG Modelworks, you may not see this but by chance if you do; what are some tips or pointers of making a mold from concrete. At that time i was 6 and my brother was 9. it was a good memory of us.

[@DGModelworks]

I'll be honest, I have no experience making molds. I hope you can find some info on it though. That would be cool.

[@BattleCat-]

Thank you so much! Just curious, how strong is plaster of paris? Does it break easily and if it does, how would i strengthen it?

[@DGModelworks]

Yes it does break easily. I'm not sure how to strengthen it, I've never tried.

[@BattleCat-]

@@DGModelworks thank you so much for the reply!

[@sharon94503]

You can add white glue.

[@OneDollarPerOneView]

Would this work if I packed down a ton of dirt or sand in a contained area over a table and poured this in layers over the dirt to create hills and mountains for a HO scale layout?

[@basilleonardo]

You'd be better to dip pieces of burlap or cloth into the wet plaster and lay it down in overlapping layers over your dirt. Crumpled paper with some masking tape to hold its shape (or just shaped chicken wire) might be cleaner.

[@booth2710]

God knows where I went wrong. I worked to a ratio of 2 parts plaster to one part water. I added the powder gradually and stirred it in carefully. Before I even finished adding all the powder it started to set in the bowl. I had visions of it setting in the bowl with the spoon stuck in it so I added even more water. I thought I made a running repair but then when I poured into into the moulds it wouldn't set. It looked like the water on a potter's wheel !

[@DGModelworks]

Sorry to hear you had troubles with this method. Not sure why it would act like that. Did you use cold water? Did you wait till you had all the powder in before you started stirring?

[@booth2710]

Update. It wasn't your method - I had not followed your method closely enough. After I posted I had another couple of goes at it and did exactly as you described. I did NOT stir it at all until I had slowly put all the mix in gradually and let the water absorb it. I also, this time, used very cold water from out of the fridge. I couldn't have gotten a better result ! I think the problems were the water wasn't cold enough and before I saw your tutorial I had watched dozens of others - many of which added the powder in stages and stirred ! This clearly is not always the right thing to do. Also I used to be a baker and a cook - among many other things and once being a baker it's very hard to get out of the habit of 'stirring and mixing things' I've learned in this craft you really have to fight the temptation to keep having a stir! I poured the mix into a silicone cake baking mould - shaped like a butterfly. After less than an hour the mould has dry enough and hard enough to remove and it came out perfect - and quite shiny. I was very please with my effort. It was too late to post last night as this kept me up until after 1.30am in the morning - and this morning I went to work looking like I had been fired out of a cannon and missed the net ! I'm definitely going to have a look at your other tutorials. But may I ask a question? Before painting is it necessary to glaze the casts before painting? I intend to use acrylic paints but have read suggestions that casts should be primed with acrylic gesso or even watered down PVA glue? (I think it's also called PVA glue in the states? ...

[@DGModelworks]

Great! Glad to hear everything came out good. As far as adding a glaze. I don't, because I make rock castings for model railroading. I paint them directly with acrylic craft paint. The castings do absorb some of the paint, and are a flat dull appearance. If you are looking for a more gloss appearance you may want to try the glaze. I've never tried that before.

[@booth2710]

I have to give you an update. I've been doing some more castings and made quite a few items now - mainly small'sh ornaments using silicone baking trays for buns - the fancy type ones. I have gotten very good at this now and apart from some minor problems with 'pesky air bubbles'I have made some great items. I I have reached the stage now where I am about to roll out a workshop for a group of over 50's (I am a community support worker in London for Older Adults) and I am very excited about this work shop starting. I had to come back here now and comment on just how much your video tutorial has helped - it's been great advice and a great tutorial. So many thanks for taking the time and trouble to post this tutorial. This has been a bit of and adventure or me but I think I can summarize the key skills to be successful with P of P work = three P's. Preparation - have everything you need ready. Patience - be patient with the work especially when mixing and Privacy- do this when you have time and can be sure of no interruptions ! I am looking forward to progressing to casting more adventurous items Many thanks !

[@DGModelworks]

Thank you so much for coming back and giving the update. I'm very happy this was a useful technique and that you are having much success with it. I think it's great what you are doing with the workshop group and glad you are able to use this method to your advantage. I love the 3 'P's. That's a great way to summarize it. Thank you again for taking the time to stop back, and leave such a positive reply. This was one of my first videos, and isn't recorded very well, but I feel the substance is still there, and still provides all the necessary info. Again, Thank you! ~Deryk

[@biganthonynasta3715]

Big Anthony art east Boston ma🎨😎

[@sherimonk6104]

Hey Derick, I found a train in a plastic bag when cleaning a commercial Parking lot. The parking lot had a small wooded area. I was picking up trash that people had been dumping. When I grab the plastic bag it was buried in the ground. I uncovered it and it was a whole train set. I’m sure it not the kind your looking for LOL! Anyway just wanted to share. Also is there a need for something like that? I guess what I’m trying to say is is it worth spending time cleaning, painting and trying to sale it or do I give it to someone like you who enjoys trains?

[@DGModelworks]

Hi, Sheri! The only way it will be worth anything at all, is if it's a sought after, Lionel train. And if it is...you most certainly DON'T want to repaint it. That will destroy the value.

[@MrDavidock]

Question. I use just starting using Plaster of Paris to cast smaller molds that I use to build Dungeons and Dragons terrains/structures. Even after roughly 30 minutes, as I'm trying to demold, the pieces are brittle and will break easily if I'm not careful. Should I wait longer? Maybe my proportions aren't right.

[@DGModelworks]

Let them dry longer. That should fix your problem. Good luck!

[@prathamdhillon5223]

i used plasture of paris i put it in a mould but when i take it out....there where cracks in it and when i hold it up it suddenly broke .. ehat should i do to avoid these cracks???

[@jeffreyyeager1398]

Thanks for the info, I have been trying to stir it as I sprinkled the plaster of Paris into the water and it's about hard till I get it to my forms. I am ready to give up but I think you might have something there. I am going to start over again. any particular kind of dish detergent for a release agent? I heard cooking spray but have not tried to get my mess out of my form yet. I'll let you know how I do.

[@DGModelworks]

+Jeffrey Yeager I've found this method to be the least stressful of all. I really hope it works for you too! As for the releasing agent, I just use a couple drops of Dawn in a spray bottle of water. Good luck!

[@davidcurtis5398]

Just use any kind of dish soap. Cooking oil might make a mess - I don't know because I've never tried it.

[@davidcurtis5398]

Tried cooking oil last evening and it didn't work any better than the "wet" water. Found out that you need to leave the mold to dry longer than I was. Left it longer and had no breaking problems.

[@amygiacomelliart]

I've used cooking spray, works great. Just don't use too much.