Post by Andrew on Feb 3, 2011 23:17:13 GMT -6
This is a handy article I found about resin work. Hopefully you find it useful!
Equipment
Dust Mask
When filing or sanding resin components, it is usually a good idea to wear a face mask. Like any fine dust, breathing resin dust is not particularly good for you. These masks can be cheaply bought from most hardware stores- a simple gauze mask with rubber-band straps to hold it in place are the bare minimum requirement.
Hobby Knife
Recent governmental legislation in some parts of the world has made it increasingly difficult to obtain good craft knives, but nonetheless you are going to need one. This is usually a handle with interchangable blades. Scalpels and models with retractable blades are also available. Get one with a fine handle and one with a heavier handle. They are available with all kinds of plastic, metal or rubber handles. Pick one that feels comfortable in your hand. If you only buy one tool, make it a good knife - it will be necessary for cleaning up "flash" prior to assembly.
Glue
There are many different types of glue. In order to work with resin kits, you can use only normal modelling glue, although this is not really a worthwhile option as it wont bond properly, so the parts will eventually fall off. Ideally, you will have different glues for different kit materials. Buy some cyano-acrylate "super-glue" - both the thin quick-setting and the thicker gap filling types for strong "longer-life" sticking. Also for the eventual basing (if you base them), get some white glue (PVA). For some resin kits, a two-part epoxy might be necessary.
Files and Sandpaper (medium, fine and extra-fine)
After a knife, a set of files is the most useful part of your tool kit. They are used for cleaning and smoothing castings and filing pieces 'to fit' where necessary (a necessary step due to the nature of resin castings). Files come with several different profiles: flat, round, half-round, and several other shapes. These can be worked in tighter areas than sandpaper and will be easier to work around cast surface details. It is a good idea to have as wide a selection as you can afford. Sandpaper or sanding pads (I use my Girlfriend's disposable nail-files!) are also useful for sanding larger areas, or getting a straight finish over a larger area. Purchase a selection of papers from 220 to 600 grit.
Saws
There are many types of saws. Probably the best for working with a resin kit is a jeweller's saw. A jeweller's saw gives very fine cuts but the blades are quite fragile.
Pin Vise and Drill Bits
You will need one of these if you want to drill holes in your components. This is usually only necessary if you want to add strength to a join with large and/or heavy components by pinning them with metal rod, or if you wish to hollow out openings or gun-barrels on solid resin castings.
Clippers
Clippers are useful for removing pieces of plastic,metal or resin that are too large to safely remove with a knife. They are also faster and easier to use than a saw so make a good middle ground tool. Start with a sprue nipper and a fine pair of scissors. Get a few types that are well made and they should last a long time.
Tweezers
These are great for picking up and holding small parts, and (for some of us!) necessary for placing decals exactly where you want them. Get at least one pair of extra fine needle pointed tweezers.
Clamps
Clamps are very useful for holding parts together while the glue dries, as well as to hold parts in a specific position while they are being worked on. I actually use clothes pegs which are very useful and work really well.
Pliers
Pliers come in handy when you need to hold small parts so that you can work on another section of that part. The most useful ones are "needle-nose" pliers.
Toothpicks
These come in handy when you need to make small wedges, or to hold small parts while painting them, or to apply small amounts of glue...
Paintbrushes
Get a varied selection. Purchase some inexpensive brushes for broad coverage and for applying washes. These are also good for setting decals. Don't skimp on good brushes for detail work or your finish will suffer.
The next step is to start preparing the Model for assembly. As this is a multi-stage process, which I'll go through step by step.
1. Washing
Clean the parts thoroughly with a mild soap in lukewarm water. The reason for doing this is to make sure all traces of mould release fluids are removed. It also gives a very slight abrasion to the surface of the model that will help with paint adhesion. Use a sponge or soft brush. Be careful not to damage or break off any cast-on detail parts. I usually leave the components to soak for a little while before scrubbing, and again for a little while after. Then remove the models, rinse thoroughly and allow them to dry.
This isn't always necessary but I find it's generally better to be safe than sorry, especially as it will be that much more difficult to do once you have assembled the kit and begun painting it!
2. Removing the parts from the Sprues
Just like with metal and plastic models, there will be excess material that needs to be removed from the parts of the kit before you can assemble it. The main difference is that, with resin models, the bits needing removal can be larger and must be removed with more care. These are the result of the casting process and unavoidable but all can be easily dealt with.
The mould plug is the area where the resin is poured into the mould. This is the biggest piece of excess resin. A mould plug can appear in many different shapes, depending on the shape of the model. The most common are V shapes that are on the side of a detailed or odd shaped component or a large rectangle going onto a squared component. These will need removing and may take some effort with a larger part.
Check the instructions again to be sure that the items you see are actually mould plugs and not part of the kit. To remove the larger parts from the mould plug, especially when it is too large to use clippers easily, cut them off with a saw. Unlike with clippers, this can be done as close to the model as you like. It's usually best to do it slightly away from the join though just to make sure that any deviation in your cutting line doesn't affect the model. Again after the mould plug has been removed, use a file to ensure a smooth finish to the surface.
With smaller components, a pair of clippers and a file should suffice. Don't twist the parts off the sprues - this is the best way to damage them.
Be careful not to apply too much pressure whilst using clippers - resin is brittle.
3. Removing Flash
First check that what you are removing is not part of the actual model. To remove these lines, use a modelling knife, file or sandpaper and carefully scrape or file away the line. This shouldn't take too long and makes a big difference to the finished model. Repeat this process for each part, paying special attention to small detail pieces.
Assembly
So, now we reach the point where we actually begin assembly.
Glues
You will need cyano-acrylate (CA) glue to assemble your model. CA glue, also known as superglue, bonds just about anything very strongly (including skin), but the bonds formed are weak unless the mating surfaces are clean, absolutely dry and fit well. Superglue is best applied with a small toothpick. The better the fit between the parts to be joined, the stronger the bond. Be extremely careful when working with superglue glue. It contains some minute quantity of cyanide, which is a toxic compound. Use it in a well-ventilated area and don't breathe the fumes. Never, ever heat it to make it cure faster.
Pre-assembly
Once the components have been washed and all excess resin has been removed, the model should be ready for assembly. If the model has any interior detail, now might be the best time to paint it, as it could be difficult once the model is assembled.
Dry-fitting
Before gluing the components together, it is a good idea to dry fit them. This just means placing the parts together to make sure they fit okay. This is useful, as it will point out any potential problems such as uneven joins and slight gaps in the joins. Unfortunately gaps are unavoidable with some joins. If there is an uneven join just quickly take a file to it and make it flat before gluing. Or if you are planning on adding extra detail with Green Stuff fill thes gaps with it too.
Warped Parts
Warpage can easily occur with thin components as thin resin components are susceptible to temperature just after casting. To get a warped piece into the right shape (or even to just reshape a piece like a piece of track) just immerse it in hot water and gently bend it. With a larger piece it is best to do this in stages. Bend it a little, allow it to settle and repeat until it is in the correct shape. Larger pieces may also require longer immersion to soften. If you don't want to use hot water then a hair dryer should give the same results, just don't let the piece get too hot (or blow away!). Do not heat resin with any kind of flame.
Assembling Resin Parts
Glue the components together straight- don't worry if there is an occasional gap, those can be taken care of in the next stage. It may be an idea to leave off some of the more fragile and smaller parts until after you have painted the main assembly. If this is the case, make sure the joint won't be too apparent afterward, since you won't be able to apply putty on the painted surfaces.
Occasionally there may be gaps where parts meet, or where a small bubble (void) is present in the resin. It's best to glue all your components that will need filling at the same time as it will save you time and Green Stuff.
Green Stuff is a malleable substance that hardens when it dries. Green Stuff comes in small, packages from Games Workshop, and several brands are available at your local hobby store.
Finishing Assembly
Once the entire model is assembled, apart from the odd little bits that have been left off to simplify the painting process, we need to wash and rinse the whole model again, in order to remove any oils left by our fingers and whatever tools we have used.
When you've reached this stage you are now ready to prime and paint the model!
Equipment
Dust Mask
When filing or sanding resin components, it is usually a good idea to wear a face mask. Like any fine dust, breathing resin dust is not particularly good for you. These masks can be cheaply bought from most hardware stores- a simple gauze mask with rubber-band straps to hold it in place are the bare minimum requirement.
Hobby Knife
Recent governmental legislation in some parts of the world has made it increasingly difficult to obtain good craft knives, but nonetheless you are going to need one. This is usually a handle with interchangable blades. Scalpels and models with retractable blades are also available. Get one with a fine handle and one with a heavier handle. They are available with all kinds of plastic, metal or rubber handles. Pick one that feels comfortable in your hand. If you only buy one tool, make it a good knife - it will be necessary for cleaning up "flash" prior to assembly.
Glue
There are many different types of glue. In order to work with resin kits, you can use only normal modelling glue, although this is not really a worthwhile option as it wont bond properly, so the parts will eventually fall off. Ideally, you will have different glues for different kit materials. Buy some cyano-acrylate "super-glue" - both the thin quick-setting and the thicker gap filling types for strong "longer-life" sticking. Also for the eventual basing (if you base them), get some white glue (PVA). For some resin kits, a two-part epoxy might be necessary.
Files and Sandpaper (medium, fine and extra-fine)
After a knife, a set of files is the most useful part of your tool kit. They are used for cleaning and smoothing castings and filing pieces 'to fit' where necessary (a necessary step due to the nature of resin castings). Files come with several different profiles: flat, round, half-round, and several other shapes. These can be worked in tighter areas than sandpaper and will be easier to work around cast surface details. It is a good idea to have as wide a selection as you can afford. Sandpaper or sanding pads (I use my Girlfriend's disposable nail-files!) are also useful for sanding larger areas, or getting a straight finish over a larger area. Purchase a selection of papers from 220 to 600 grit.
Saws
There are many types of saws. Probably the best for working with a resin kit is a jeweller's saw. A jeweller's saw gives very fine cuts but the blades are quite fragile.
Pin Vise and Drill Bits
You will need one of these if you want to drill holes in your components. This is usually only necessary if you want to add strength to a join with large and/or heavy components by pinning them with metal rod, or if you wish to hollow out openings or gun-barrels on solid resin castings.
Clippers
Clippers are useful for removing pieces of plastic,metal or resin that are too large to safely remove with a knife. They are also faster and easier to use than a saw so make a good middle ground tool. Start with a sprue nipper and a fine pair of scissors. Get a few types that are well made and they should last a long time.
Tweezers
These are great for picking up and holding small parts, and (for some of us!) necessary for placing decals exactly where you want them. Get at least one pair of extra fine needle pointed tweezers.
Clamps
Clamps are very useful for holding parts together while the glue dries, as well as to hold parts in a specific position while they are being worked on. I actually use clothes pegs which are very useful and work really well.
Pliers
Pliers come in handy when you need to hold small parts so that you can work on another section of that part. The most useful ones are "needle-nose" pliers.
Toothpicks
These come in handy when you need to make small wedges, or to hold small parts while painting them, or to apply small amounts of glue...
Paintbrushes
Get a varied selection. Purchase some inexpensive brushes for broad coverage and for applying washes. These are also good for setting decals. Don't skimp on good brushes for detail work or your finish will suffer.
The next step is to start preparing the Model for assembly. As this is a multi-stage process, which I'll go through step by step.
1. Washing
Clean the parts thoroughly with a mild soap in lukewarm water. The reason for doing this is to make sure all traces of mould release fluids are removed. It also gives a very slight abrasion to the surface of the model that will help with paint adhesion. Use a sponge or soft brush. Be careful not to damage or break off any cast-on detail parts. I usually leave the components to soak for a little while before scrubbing, and again for a little while after. Then remove the models, rinse thoroughly and allow them to dry.
This isn't always necessary but I find it's generally better to be safe than sorry, especially as it will be that much more difficult to do once you have assembled the kit and begun painting it!
2. Removing the parts from the Sprues
Just like with metal and plastic models, there will be excess material that needs to be removed from the parts of the kit before you can assemble it. The main difference is that, with resin models, the bits needing removal can be larger and must be removed with more care. These are the result of the casting process and unavoidable but all can be easily dealt with.
The mould plug is the area where the resin is poured into the mould. This is the biggest piece of excess resin. A mould plug can appear in many different shapes, depending on the shape of the model. The most common are V shapes that are on the side of a detailed or odd shaped component or a large rectangle going onto a squared component. These will need removing and may take some effort with a larger part.
Check the instructions again to be sure that the items you see are actually mould plugs and not part of the kit. To remove the larger parts from the mould plug, especially when it is too large to use clippers easily, cut them off with a saw. Unlike with clippers, this can be done as close to the model as you like. It's usually best to do it slightly away from the join though just to make sure that any deviation in your cutting line doesn't affect the model. Again after the mould plug has been removed, use a file to ensure a smooth finish to the surface.
With smaller components, a pair of clippers and a file should suffice. Don't twist the parts off the sprues - this is the best way to damage them.
Be careful not to apply too much pressure whilst using clippers - resin is brittle.
3. Removing Flash
First check that what you are removing is not part of the actual model. To remove these lines, use a modelling knife, file or sandpaper and carefully scrape or file away the line. This shouldn't take too long and makes a big difference to the finished model. Repeat this process for each part, paying special attention to small detail pieces.
Assembly
So, now we reach the point where we actually begin assembly.
Glues
You will need cyano-acrylate (CA) glue to assemble your model. CA glue, also known as superglue, bonds just about anything very strongly (including skin), but the bonds formed are weak unless the mating surfaces are clean, absolutely dry and fit well. Superglue is best applied with a small toothpick. The better the fit between the parts to be joined, the stronger the bond. Be extremely careful when working with superglue glue. It contains some minute quantity of cyanide, which is a toxic compound. Use it in a well-ventilated area and don't breathe the fumes. Never, ever heat it to make it cure faster.
Pre-assembly
Once the components have been washed and all excess resin has been removed, the model should be ready for assembly. If the model has any interior detail, now might be the best time to paint it, as it could be difficult once the model is assembled.
Dry-fitting
Before gluing the components together, it is a good idea to dry fit them. This just means placing the parts together to make sure they fit okay. This is useful, as it will point out any potential problems such as uneven joins and slight gaps in the joins. Unfortunately gaps are unavoidable with some joins. If there is an uneven join just quickly take a file to it and make it flat before gluing. Or if you are planning on adding extra detail with Green Stuff fill thes gaps with it too.
Warped Parts
Warpage can easily occur with thin components as thin resin components are susceptible to temperature just after casting. To get a warped piece into the right shape (or even to just reshape a piece like a piece of track) just immerse it in hot water and gently bend it. With a larger piece it is best to do this in stages. Bend it a little, allow it to settle and repeat until it is in the correct shape. Larger pieces may also require longer immersion to soften. If you don't want to use hot water then a hair dryer should give the same results, just don't let the piece get too hot (or blow away!). Do not heat resin with any kind of flame.
Assembling Resin Parts
Glue the components together straight- don't worry if there is an occasional gap, those can be taken care of in the next stage. It may be an idea to leave off some of the more fragile and smaller parts until after you have painted the main assembly. If this is the case, make sure the joint won't be too apparent afterward, since you won't be able to apply putty on the painted surfaces.
Occasionally there may be gaps where parts meet, or where a small bubble (void) is present in the resin. It's best to glue all your components that will need filling at the same time as it will save you time and Green Stuff.
Green Stuff is a malleable substance that hardens when it dries. Green Stuff comes in small, packages from Games Workshop, and several brands are available at your local hobby store.
Finishing Assembly
Once the entire model is assembled, apart from the odd little bits that have been left off to simplify the painting process, we need to wash and rinse the whole model again, in order to remove any oils left by our fingers and whatever tools we have used.
When you've reached this stage you are now ready to prime and paint the model!
