Making casts of my arms?

[Egon Spengler]

I'd like to make a mold and then make forms of my arms from it. I can only think of using plaster but I know that plaster can burn.

What else can I use to do this? If I did use only plaster how can I do this safely?

 

[GuntahKela]

http://www.smoothonsecure.com/store/index.php?cPath=58_274&osCsid=b03bcbc08faf1db73c5282ce4d8f9d18

 

[Robot Monster]

www.indymogul.com has some stuff on hand casting that would apply.

 

[weaselflinger]

What do you plan to cast with? How many copies do you plan to cast? How durable do they need to be?

If all you need is a quick and dirty mold without a high level of detail, a two-part mold of plaster bandages will work just fine. Just be sure to shave your arms and use a seperator like vasiline.

 

[troopermaster]

I used regular bandages dipped in plaster of paris to make my body castings. You could also use hessian or old clothes cut up will do as well to reinforce the plaster. No need for shaving, just wrap your arm with cling film and your good to go.

 

[Cptnchaos]

REAL simple way to do it.

Get a LARGE thick poster tube or if your arms are thicker get a PVC pipe that when you stick your WHOLE arm into and wide enough so you have at LEAST 1/2 of an inch between your arm and the inside wall of the tube. Cap off one end with plastic wrap and a bunch of duct tape to reinforce this.

Next mix up some FAST setting alginate. Pour it into the tube to fill it half way.

Stick your arm in. ALL of it. Add more alginate as needed to fill the tube up.

** MAKE SURE YOU DONT MOVE and that your arm is NOT touching the sides of the tube!!**

Now stand or sit uncomfortably until the alginate has set. If you think you can do this without moving your arm, gently tap on the sides of the pipe to free any air bubbles in the alginate. You will KNOW its set when it has become a solid.

Flex your muscles and wiggle your fingers to free yourself and slowly pull your arm out of the tube. Be careful NOT to let any alginate crumbs or chunks fall into the tube. If they do, just carefully invert the tube and tap it until it is visible to pull out.

NEXT: mix up some Hydrocal or Ultracal and slowly pour it into the mold. Slush a SMALL amount around inside to make sure you get the finer details. then pour more in until you fill your pipe.

KEEP THE BOTTOM OF THE TUBE FLAT ON THE GROUND. Also keep it supported so it wont tip over.

If you think you want to mount this to an armature place a dowel or large rod into the center of the ultracal/hydrocal.

Wait 24 hours or follow the directions on whatever you used before you free the cast from the tube.

CAREFULLY remove the alginate from the plaster and there you have it.

If you have any questions feel free to Email me.

Damian

I used regular bandages dipped in plaster of paris to make my body castings. You could also use hessian or old clothes cut up will do as well to reinforce the plaster. No need for shaving, just wrap your arm with cling film and your good to go.

​

 

[Egon Spengler]

I used regular bandages dipped in plaster of paris to make my body castings. You could also use hessian or old clothes cut up will do as well to reinforce the plaster. No need for shaving, just wrap your arm with cling film and your good to go.

Doesn't plaster get hot though? How do you keep from getting burnt?

 

[Egon Spengler]

Bump

 

[jedikanol]

http://www.bioweapons.com/castingHandsFeet.htm this guy has a lot of info on casting hands and arms just need to get Alginate and bam got your self a cast fo your arm or feet. and of corse the hydrocal

 

[Beeb89]

Plaster gets warm but not hot, at least not so hot it would burn you. I used plaster to make a partial face mold and had no problems at all.

-B89!

Doesn't plaster get hot though? How do you keep from getting burnt?

 

[Cptnchaos]

Doesn't plaster get hot though? How do you keep from getting burnt?

You will not get burned. Unless you have THE most sensitve skin in the world. Tough it out soldier this is for the craft!!

Email me if you have any questions.

Damian

 

[drcrash]

Plaster can burn and CUT you (Re: Making casts...)

Thick plaster CAN burn you. Plaster releases heat as it sets, and thick plaster can get very hot. Thin plaster (like a very few layers of plaster bandage) is generally not a problem that way, because there isn't enough volume of plaster per unit surface to be a problem.

What you really DON'T want to do is make a poured plaster mold of somebody's face, which is inches deep over the lower parts of the face, and thin over the nose. If their eybrows, etc. stick in the plaster and you can't easily take it off quickly, you're asking for trouble.

Another way that plaster is dangerous is that it can cut you, if you cast it over folds of flesh (like where a natural breast sags and meets the chest wall at a sharp angle, or creases rolls of flab). The cast plaster can make a knife-sharp edge where the pieces of flesh meet at an acute angle, and that edge can cut right through skin and the underlying tissues when the model shifts or tries to get out of the cast. (The plaster is brittle but hard and sharp, so depending on the forces and angles, it may just break, or may slice neatly through flesh.)

That's one reason most lifecasters use alginate... once you've put a layer of alginate on, you've filled in any sharp concavities, rounding things out, and the rigid plaster mother mold isn't sharp.

If you're doing a female torso in straight plaster, and you don't need pore-level detail, one thing you can do for a natural-looking effect is cast your model wearing a single-layer, stretchy but slightly supportive bra that still gives a "natural-looking" overall shape, but without a sharp edge where the breast meets the chest wall, and gives a protective layer or two of cloth (and maybe an underwire) there at the sharp undercut. You can fill in the bra straps & underwire marks in the mold and get something nice-looking in the cast that just requires some minor finishing to erase the evidence of the bra.

 

[drcrash]

BTW, the methods usually used for hands or feet are usually terribly wasteful for arms or legs. You don't need a big cylinder full of alginate, which is not terribly cheap. You just need a layer of alginate about 1/4" thick, and a laid-on plaster bandage mother mold to hold it in shape. Then the alginate usually costs less than the other costs. (The mother mold and the plaster you cast in the mold.) It only takes about $5 worth of alginate to do a face, for example.

Depending on what you need the casting for, it may make sense just to use plaster bandages, but if you need good detail OR if there's a sharp place where flesh meets flesh, like a sharply crooked arm, you may want to go with alginate.

 

[Egon Spengler]

Wow! A LOT of great informaton! Thanks!

Where can I buy alginate? Can I get it in stores that aren't online?

 

[MjolnirArmor]

you can put wet paper towels on your arms if you don't want them to burn (shouldn't anyways)

 

[drcrash]

Wow! A LOT of great informaton! Thanks!

Where can I buy alginate? Can I get it in stores that aren't online?

Hobby Lobby sells something called InstaMold, which is actually a regular (fast setting) alginate, but I wouldn't bother with it. (Annoyingly, it doesn't say on the package that it's alginate---they make it sound like some unique miracle product.) They sell it in a small package that isn't a good deal for large stuff, and I much prefer slow-setting alginate. InstaMold is hard to mix and apply before it sets up.

I'm not sure if you can find the slow setting stuff locally. Everybody seems to buy online. (We used "Algiform Slow Set" alginate from www.pinkhouse.com and are very happy with it, so we've stuck with it.) If you live some place like LA, you probably have more choices.

I think you can get alginate at dental supply stores, but I suspect it's not the slow-setting stuff.

You can control the setting time to some extent by using cold water, but regular setting alginate still sets up fast, and your model probably will get goosebumps. (Or on the face, a bit of a "yaah! that's cold!" wincing expression.)

 

[thorssoli]

I posted a step-by-step of my arm molding procedure on my myspace blog at the following link:

http://blog.myspace.com/index.cfm?fuseaction=blog.view&friendID=30140919&blogID=319589297

The alginate I used here was actually purchased on ebay for about $5.00 per pound.

I've done lifecasting using plaster placed directly against the skin in the past. I can tell you from painful personal experience that you CAN very much burn yourself this way. There are ways to prevent it, but if you've got any doubts at all about the process, you're better off using alginate.