Casting Blocks

[Ron Tamburrini]

Hi guys and Gals

Firstly happy New Year.

Regards the topic,casting blocks! can anyone shed light on why some manufacturers products
have little or none while others have copious amounts, is it due to complexity or cost of removing
before dispatching out for general release ,oh and before I raise hackles here this is an enquiry and not an attack on anyone
The reason behind this is one of general health as there are large amounts of dust no mater what method is used for removal albeit hand saw and sandpaper or dermal which I use for speed and no doubt others do also. Given the amount of figures that some of you chaps work through I think serious considerations must be taken into account as this stuff "resin" is just another danger in our hobby ,along with lead,carcinogenic glues putty's and paints and mineral spirits ,and don't forget the almost obligatory Air brush and the health issues with this wondrous tool.

Ron

 

[stu]

All the best ron...lets hope 2013 with its ominous number is a good one.

Casting blocks. ....its down to 2 factors

1 how the figure was moulded/sprued up and the experience of the person moulding the figure/piece. Its also how far they are prepared to push the vents and pouring points to achieve a flawless casting. To some degree the master has a part in this and how the sculptor has brocken the piece down.

2 Whether the producer has been bothered to attempt to take these off which is quite time consuming and boring. This all comes down to cost and you pays for what you gets so cheaper kits probably dont go that extra mile but not always.

Use clippers if you able and scrape/ slice the blocks off. I never dremel.

Hope this helps

Will be watching....there are some good casters/ moulders on here so it will be interesting to here what they think

Stuart

 

[Ron Tamburrini]

All the best ron...lets hope 2013 with its ominous number is a good one.

Casting blocks. ....its down to 2 factors

1 how the figure was moulded/sprued up and the experience of the person moulding the figure/piece. Its also how far they are prepared to push the vents and pouring points to achieve a flawless casting. To some degree the master has a part in this and how the sculptor has brocken the piece down.

2 Whether the producer has been bothered to attempt to take these off which is quite time consuming and boring. This all comes down to cost and you pays for what you gets so cheaper kits probably dont go that extra mile but not always.

Use clippers if you able and scrape/ slice the blocks off. I never dremel.

Hope this helps

Will be watching....there are some good casters/ moulders on here so it will be interesting to here what they think

Stuart

Happy new year Stu
I had hoped you would come in on this one as I new you would have some good answers.
Never Dremel!! Reason?

ron

 

[housecarl]

Never Dremel!! Reason?
Dust Ron.
PPE mate, and don't forget the hard hat.
Carl.

 

[Mark S]

Back in my day we had to chew through asbestos packaging soaked in creosote just to get to our oxidzing metal figures which were wrapped in loose, crumbling fibreglass sheeting. Then we had to clean them in whatever polycyclic aromatic hydrocarbons we could get hold of, then lick them clean before filing the joins and seamlines with rough asbestos blocks held between our teeth. Once we'd got our figure glued with boiled down rabbit hides they were ready for painting with toxic lead paint thinned with Methyl-benzene.....and we thought we were the bees knees,the ants pants and the ducks nuts. Still tell that to the younguns these days and they won't believe ya.

But seriously though, Ron what you say is very important indeed. Many activities in todays world, including what we all do in our hobby, put us all at risk of injury or adverse health consequences if we don't take precautions and if we become complacent about the obvious risks involved.

 

[Ron Tamburrini]

Back in my day we had to chew through asbestos packaging soaked in creosote just to get to our oxidzing metal figures which were wrapped in loose, crumbling fibreglass sheeting. Then we had to clean them in whatever polycyclic aromatic hydrocarbons we could get hold of, then lick them clean before filing the joins and seamlines with rough asbestos blocks held between our teeth. Once we'd got our figure glued with boiled down rabbit hides they were ready for painting with toxic lead paint thinned with Methyl-benzene.....and we thought we were the bees knees,the ants pants and the ducks nuts. Still tell that to the younguns these days and they won't believe ya.

But seriously though, Ron what you say is very important indeed. Many activities in todays world, including what we all do in our hobby, put us all at risk of injury or adverse health consequences if we don't take precautions and if we become complacent about the obvious risks involved.

Help ma boab ! I never realised Birds had nuts

 

[Mark S]

Help ma boab ! I never realised Birds had nuts

Of course they do, we wouldn't have any more birds if they didn't......they're just hard to see with all those feathers and stuff,not that I've ever looked that hard.......but you must've seen a duck walking.

 

[Ron Tamburrini]

Of course they do, we wouldn't have any more birds if they didn't......they're just hard to see with all those feathers and stuff,not that I've ever looked that hard.......but you must've seen a duck walking.

Sorry Mark I thought you meant Sheilla,s when you said birds or should I say burds

 

[jasmils]

Happy New year to all.
Admittedly I mostly produce armour and related kits but I do a couple of figures as well. However, I pride myself on just how small I can keep my casting blocks and sprue.
From this point on, I'm talking about the resin casting and not the mould making process.
The size of the casting block to be removed comes down to a couple of factors, do they (the manufactures) use just pressure casting, or just vacuum casting, or like me vac and pressure.
If you are just using just one casting method, the casting/sprue block needs to be quite large to allow the resin in and the air out. This method is quite cheap and fast to produce the parts. It is also preferable when using cheap polyurethane due to the shrinkage of the resin.
The 1st vac and pressure method is basically vacuuming the resin in a cup, then pouring the resin into the mould. Then placing it under pressure. Again, quick and cheap. But you will still need large blocks and vents.
With the 2nd vac and pressure method, the resin is poured into the mould. It is them vacuumed, topped up with resin and placed into the pot under pressure until the resin goes off.
This method is a lot slower than the other ones, but the parts only need a very small sprue, or sometimes no sprue or block.
I can get very complex parts with the most minimal of clean up using this method and most of my sprue's are between .25mm and 1.5 mm thick.

Cheers Jason

 

[Babelfish]

Given the amount of invisible crap in the ambient air that we all unknowingly (and largely unavoidably) inhale every day, I don't buy into all the "resin dust will kill you" hysteria that sometimes gets pedalled.

Don't get me wrong - I would never go out of my way to inhale the stuff, and whenever I work with it I alway try and keep the amount of sanding and drilling to a minimum and/or wear a mask. But I don't fret unduly over it either, because in the grand scheme of things it's probably no more or no less harmful than most other common types of dust (e.g. wood dust), and of course ANY dust in large amounts can be harmful.

Probably if you're working with it intensively every day and inhaling "industrial" quantities, it's a different matter because your exposure is going to be so much greater. But for your average hobbyist (who if they're anything like me don't get to spend anywhere near as much time at the bench as they'd like), it's probably no big deal.

Ditto glues, paints etc. Just work in a well ventilated room, keep your "hobby materials" out of your various cavities and orifices, wear a mask if working with smelly and/or dusty stuff, keep calm and just carry on.

Some years back when I was living in Germany, I got into a conversation with another modeller who was banging on about how dangerous resin is and how you should always mask up in its presence etc. etc. And yet this was a bloke who apparently thought nothing of smoking 40 cigarettes a day. I remember laughing to myself about that and have never forgotten it.

Happy modelling!

- Steve

 

[Mark S]

Sorry Mark I thought you meant Sheilla,s when you said birds or should I say burds

Actually, Ron there is a pub near where I live called "The Duck's Nuts".....I went there once when I got tired of waiting for "The Queen's Legs" to open.

 

[Ron Tamburrini]

Actually, Ron there is a pub near where I live called "The Duck's Nuts".....I went there once when I got tired of waiting for "The Queen's Legs" to open.

 

[Einion]

The dangers from resin dust are commonly exaggerated as resins are actually quite inert in their solid form; just as with the danger posed by pigments the major risk is on the production side of things, not with the end consumer.

That's not to say resins don't pose a risk to anyone but it's nothing to fret over if you're otherwise in good health and take common-sense precautions if you are generating dust (particularly anyone that is still grinding* it routinely).

Incidentally Ron lead shouldn't be anything to worry about with modern metal castings because of health-and-safety regs.

Einion

*Better to use a cutter head rather than grinding stones or sanding drums if doing bulk removal with a motor tool.

 

[old grumbler]

Use plenty of water when tooling resin and add a small amount of washing up liquid, that way it won't get into the air and more importantly your lungs.

 

[Ron Tamburrini]

Some good points on this one Guys

Ron

 

[housecarl]

Haven't even touched on the dangers of wood dust Brian some real nasty stuff there especially among the lesser known
South American hard woods

Iroko used to make me sneeze like mad, nasty stuff.
Carl.

 

[Ron Tamburrini]

Iroko used to make me sneeze like mad, nasty stuff.
Carl.

Dead on there Carl very dense and saw dust like graphite powder does polish nice though ,got a small slab of the stuff here.
Sometimes used as a sub for Teak ,another nasty one ,splinters can poison

 

[Mark S]

 

[Tubby-Nuts-REMOVED]

There is always the option of using, 'Surgical-Gloves', and a 'Dust-Mask',... which would negate most concerns!... and a mini hoover.....

 

[Tubby-Nuts-REMOVED]

You could always go over-board!.......