I read a feature article here where one could make copies of bags, etc. by using the glue gun. My question is: what material for the mold can I use for this method of making casts besides RTV? Could plaster be a suitable material mold for the glue gun casts?

Since plaster is a 'cold' pour (unlike resin which creates heat) I would think the glue gun trick would be fine for plaster.
One thing to be careful of is that plaster if fairly brittle and if you have a complex undercurve or fold or something it might be hard to get the piece out of the mold.

I use scenic woodland latex rubber for plaster molds. It runs $8 us for a jar that looks to be big enought to last for ever! I know that MicroMarc on line has latex also.

I say give it a try.

Hi,

I use the Glue Gun methode.

I only use RVT on big pieces, but for small ones like bags, ammo pouches and little ammo boxes I always use LATEX rubber with bandage for strenght.

If you want to see how the glue gun methode works dan folow this link Glue gun molding, wich you can find on my website.

#:-)

Another good tip Ronny. I never thought of that. One never can have enough backpacks and things for hanging on vehicles. Cheers!

Ronny,
Interesting tip, and I'll give it a try. I'm not sure this is harmless to the mold, though. I suspect the chemicals and termperature of the glue may deteriorate the quality of the mold after only a few casts.

Question : I'm intrigued about those castle molds. What art they ? Whatt brand ? where did you find those ???

Thanks, Jan

Hi Jan,

I have casted about 40-50 backpacks this way and I still have the originel latex mold, and even that mold is 15 years old, no problems found :-)

About that castle mold, I wish I could tell you more, this mold was bought by my father when we lived in El Paso, USA in 1975, so I don't have the brand name, but I don't think you can find it in this quality anymore, I have builded several castles wit these 12 (!!!) molds and have recently given them to my oldest son and he can't stop building :-)

Sorry

Those castle molds look as if they could be Linka, a system for making buildings for model railways by casting sections in plaster. Not sure they're made any more, I've not see or heard of them for some time. Had two or three brickwork molds some time ago, to 00 gauge(1/76 scale). All I ever seemed to use them for was to produce rubble.

Fantastic!! I'm going to get my glue gun and try it. Question? Do you need any release agent on the mold? This is glue. I guess I'll find out soon.Thanks,JOCK

No it pops right out without any problems, but be careful the glue is HOT, found out the hard way

Neat idea. Got me thinking, would it be possible to use silicon sealant (the type you use to seal around the bath, that comes in a cartridge) as a mold? I'll have to give it a try.
Mal

No,

Silicon sealant won't work, it is not liquid enough and it will stay in a rubbery state, the glue is also not rock hard but will het harder then the silicone

No, I was thinking of using the sealant as the mold, not the casting medium. Just a thought. It probably wont work with hot glue but it might with say, plaster.
Like I say I'll give it a try.
Mal

Started experimenting today, actually looks quite promising. I'll keep you informed
Mal :-)

Holdfast - dying to hear about this development.... ok - I'll subscribe to this post to see what you have discovered in your experiment! Keep us posted!!!!

Yeah Holfast,

Let us know, and if possible show a few pictures

Getting there, it's become a bit more involved but i've made some progress. I had a go at making 2 part molds and although I got quite good detail It wont work because the mold halves tend to distort. However It looks very promising for things like burgans, rucksacks and anything that you don't need to see both sides of. I'm held up at the moment because I've ran out of Silicon sealant (I've been using some left over stuff) and I don't have any glue sticks for my hot glue gun (which was the reason for trying this in the first place). But mainly cos I'm out of work and don't have the cash to get what I need (even though I did buy a new model yesterday)ssshh. I've had another idea for a cheapish casting medium, I'll let you know when I've managed to do some more experimenting.
I will also try and post some pics.
Mal

Just a bit of an update on this silcon mold idea. Basically it will work with hot glue. I aws dying to try it so I pluged in the glue gun, there's always some left in. Although there wasn't enough to get a full cast it did prove that it will work, and the detail aint bad either, I even got quite an undercut. If it works this well with hot glue it should work like a dream with my other idea. Not saying what it is yet and its a bit more costly than hot glue sticks, so with me being out of work I certainly wont be trying it until after Christmas.
Try this for the hot glue approach:
1. Squeeze out a blob of silicon sealant.
2. Put some light oil (3 in one) on your finger or a tool of your choice and squash the blob flat but thick enough to contain you master.
3. Attach a handle to your master. drill a hole insert a cocktail stick, or a blob of blue tack, or similar. If you don't you will distort the mold as you try and get it out.
4. Oil your master and push it into the silicon. Remove the master.
5. when the silicon has cured, I gave it at least a day. Depending on the amount it could be less. Oil the mold and feed in the hot glue.
6. When it's cool remove your part.
I don't know how many copies you will get. You could use vasaline for the mold release agent. Try it I think you will be surprised what is possible with this method. Biggest problem might be air bubbles.
Mal

When I came up with the idea, I was just playing around in the garage. I used silicone RTV (the type used to make auto gaskets) and squeezed a bunch into a beer bottle cap. I used good old spit as a release agent, and pushed the part into the mold. I let it sit overnight and pulled it out . I fired up the glue gun and gave it a try with pretty good results. You might want to try using different types of glue sticks, as some melt at lower temps than others, some are sticky, etc....

Hope this helps

John

:-) Nice one John anybody else had a go? Gasket RTV may be better than silicon sealant, plastacine, Play Doh or even Blue Tack might work. I did try squeezing the silicon into a container, a part of a tube, but it didn't cure. The beer bottle tops are a great idea.
Mal :-)

hehehe Yeah, I always seem to have many sitting around......maybe that's why I never get my models finished.

John

You could try modeling clay too. I dont know if it will work but who knows. :-) :-)

Hey all,

I tried the play doh idea and it seems to be to soft to keep the shape of the part. It holds the detail great though. Another thing is that the glue tands to dry too fast with the play doh. I still have to try the modeling clay. I will let you know of any developments. :-)

Hey,

The modeling clay seems to work great. But you have to be carefull because the clay is soft and you can damage the mold very ez. The detail seems to be good to. One more thing, the clay sticks to the hot glue so you have to wash the glue off of the casting.
I will see if I can come up with any thing else that works.

The key to using modeling clay is that after you have impressed the master into the clay, you need to then put it in the FREEZER for about an hour... then the clay will temporarily harden, allowing you to pull the master out without deforming the impression! Works great with plaster, but have never tried anything hot like glue gun or resin (which generates heat).

Hmmmmm........

CHEAP........

REUSEABLE.........

I like this idea.......

Matt