How to build a resin kit
Posted: Mon Sep 03, 2012 5:29 pmFor some specific cars or body styles, the major slot car manufacturers may not be in a position to produce the car as they may forecast it as a low-selling slot car that will not offset the expense of tooling molds and manufacturing costs. Often, the only way to get that certain car that you want is to turn to a resin caster. Most resin kits are designed with medium modeling skills in mind and all kits are of varying quality. Some are slush cast (meaning a single-sided mold of the outside of the body of the car that resin is poured into and simply swirled around until cured) and some are two-part molded (where an outer mold and an inner mold are created. This allows consistent wall thickness of the cast part). Almost all resin kits will require sanding, gluing, and painting, and some might even require the builder to add mounting points for the chassis used.
While not a comprehensive list of building procedures, the following steps should help you during your resin kit build and have you racing quickly:
1. Inventory the kit parts – ensure you received all the parts listed in the description of the kit.
2. Remove all flashing. Especially around the window areas, wheel wells, and bottom of the rocker panels, etc. I find using a sanding stick sold at most hobby stores works well and they are available in various grits and sizes. I personally go to my local Wal-Mart and buy different grits of emery boards from the ladies cosmetic section as they are dirt cheap and work just as well. Just don't tell anyone... :oops:
3. Trial fit all parts. Ensure the bumpers and interior fit properly. Each of these may need some flashing clean-up or minor sanding. Ensure the interior tray fits over the chassis you plan on using.
4. Trial fit the chassis. Once the other parts have been checked out, test fit the chassis and drill the holes for the mounting screws or create the necessary mounting points. This is the best time to do this, before you lay any paint that could be damaged if you do so later. Measure and trim any axles to the proper width if needed in order to fit underneath the body shell. I then like to screw the chassis completely on and take a few laps at this time. This helps ensure that there is no tire rub or other clearance problems. Besides, it is an excuse for track time!
5. Trial fit the glass. This is another important step that seems out of place, however, it is really the best time to do so. Do you really want to paint up your kit, only to find out later that there is more sanding or flashing that needs to be dealt with? I didn't think so! Glass is often a finicky part. I find it easiest to trim the part carefully, continually refitting it to check for alignment. Go slowly. It also helps to cut it down to the center rib if so equipped. This means there is less glass attaching to the roof, and can make the windows fit that much better. In some cases, such as on my Datsun 510 kit, even though the quarter glass has been molded together with the front windshield and rear glass, the best way to fit it is to completely remove the quarter glass and install each part separately.
7. Rough up the body to allow the primer something to “bite†into. I like to use 0000 Steel Wool to rub the body and parts down. Sometimes resin is a little too smooth and can cause problem with paint adhesion. This usually won't show up until you are masking a two-toned car, remove the tape, and pull up paint and primer. :doh: In lieu of Steel Wool, 1500 grit sand paper works, however be careful you do not remove trim and detail from the body. I blow off or rinse off all parts when done.
8. Wash the body and parts in soapy water or Wesley's Bleech White prior to priming. I keep a resealable container full of the Wesley's and usually just throw the body and parts into it for about a 15 minute soak. I then rinse the body in cool water and allow it to dry. This is necessary as most casters use a resin release in order to ensure the parts come out of the mold easily and it also acts as a barrier to keep the resin from eating at the silicone of the mold. Some casters use a release that is very oily and paint products will NOT stick to it! Cleaning it up as described takes care of that problem.
9. Prime the body and parts before painting. It is very important to get a good base down for the remaining paint work to be done. I use Duplicolor Automotive Spray Paint, however, many other paints such as Tamiya, Testors, Humbrol, etc. are available. Just be sure to get one that is compatible with the type of paint you are planning to use, such as Lacquer or Enamel. I spray all sides to each part and let dry according to manufacturer's recommendations. The great thing about the Duplicolor paints is that they dry very quickly. I can usually handle a primed part in about 15-30 minutes.
10.Paint the body and parts. At this time I also paint and detail the interior tray.
11. Decal the body. I almost always use decals from http://www.slotcars4u.net on my kits. These decals are very strong and well made. They are also researched extensively and are not a generic decals for a car. Tim Millward is the gentleman that does these decals and he takes some serious pride in his work. He utilizes an ALPS printer that produces amazingly decals. He coats his decals in Future to ensure you'll have a trouble-free installation. He also includes fabulous instructions that include some of the history of the car you are modeling.
12.Final Detail. At this stage, adding trim paint around windows, vents, windshield wipers, and gas caps is a good idea if you are painting them. This way, the final clear coat will protect these areas. If you are using Bare Metal Foil, I recommend not doing so until after the clear coat, as it tends to fog and dull if you coat it.
13. Clear Coat the body. I use two coats of clear depending on my needs: Duplicolor Clear Lacquer and Future. It has changed names several times. I have a Tip & Tricks article elsewhere on my site about how to use it. A great Internet resource has surfaced that describes the different branding of this product. Check it out: http://www.swannysmodels.com/TheCompleteFuture.html
14.I like to use a clear drying craft glue like Elmer's white glue or Tacky Glue to glue the glass parts in. A good applicator is a normal toothpick, allowing you to put a very small amount on at a time. Craft glues clean up easily with water later if you accidentally place it somewhere visible. Be sure to allow the parts to dry depending on your installation method.
15.Interior Assembly. Often I'll use a low-heat glue gun to glue my interior trays in or I'll use the craft glues mentioned above. They are easy to remove later if needed. Only a little dab is needed, so don't empty the gun or cover each seam of the tray as it is not necessary, and only makes later disassembly difficult.
16.Chassis Assembly. Screw the chassis assembly to the completed and assembled body shell. Be sure to check for proper fit and that the tires spin freely inside the wheel wells and that the guide blade is able to rotate properly.
17.Race it! All of my cars see the track. I don't build cars to be shelf queens and believe that if I've spent this much time building something I want, I should at least take the time to run it. Remember, this is still a toy!
While not a comprehensive list of building procedures, the following steps should help you during your resin kit build and have you racing quickly:
1. Inventory the kit parts – ensure you received all the parts listed in the description of the kit.
2. Remove all flashing. Especially around the window areas, wheel wells, and bottom of the rocker panels, etc. I find using a sanding stick sold at most hobby stores works well and they are available in various grits and sizes. I personally go to my local Wal-Mart and buy different grits of emery boards from the ladies cosmetic section as they are dirt cheap and work just as well. Just don't tell anyone... :oops:
3. Trial fit all parts. Ensure the bumpers and interior fit properly. Each of these may need some flashing clean-up or minor sanding. Ensure the interior tray fits over the chassis you plan on using.
4. Trial fit the chassis. Once the other parts have been checked out, test fit the chassis and drill the holes for the mounting screws or create the necessary mounting points. This is the best time to do this, before you lay any paint that could be damaged if you do so later. Measure and trim any axles to the proper width if needed in order to fit underneath the body shell. I then like to screw the chassis completely on and take a few laps at this time. This helps ensure that there is no tire rub or other clearance problems. Besides, it is an excuse for track time!
5. Trial fit the glass. This is another important step that seems out of place, however, it is really the best time to do so. Do you really want to paint up your kit, only to find out later that there is more sanding or flashing that needs to be dealt with? I didn't think so! Glass is often a finicky part. I find it easiest to trim the part carefully, continually refitting it to check for alignment. Go slowly. It also helps to cut it down to the center rib if so equipped. This means there is less glass attaching to the roof, and can make the windows fit that much better. In some cases, such as on my Datsun 510 kit, even though the quarter glass has been molded together with the front windshield and rear glass, the best way to fit it is to completely remove the quarter glass and install each part separately.
7. Rough up the body to allow the primer something to “bite†into. I like to use 0000 Steel Wool to rub the body and parts down. Sometimes resin is a little too smooth and can cause problem with paint adhesion. This usually won't show up until you are masking a two-toned car, remove the tape, and pull up paint and primer. :doh: In lieu of Steel Wool, 1500 grit sand paper works, however be careful you do not remove trim and detail from the body. I blow off or rinse off all parts when done.
8. Wash the body and parts in soapy water or Wesley's Bleech White prior to priming. I keep a resealable container full of the Wesley's and usually just throw the body and parts into it for about a 15 minute soak. I then rinse the body in cool water and allow it to dry. This is necessary as most casters use a resin release in order to ensure the parts come out of the mold easily and it also acts as a barrier to keep the resin from eating at the silicone of the mold. Some casters use a release that is very oily and paint products will NOT stick to it! Cleaning it up as described takes care of that problem.
9. Prime the body and parts before painting. It is very important to get a good base down for the remaining paint work to be done. I use Duplicolor Automotive Spray Paint, however, many other paints such as Tamiya, Testors, Humbrol, etc. are available. Just be sure to get one that is compatible with the type of paint you are planning to use, such as Lacquer or Enamel. I spray all sides to each part and let dry according to manufacturer's recommendations. The great thing about the Duplicolor paints is that they dry very quickly. I can usually handle a primed part in about 15-30 minutes.
10.Paint the body and parts. At this time I also paint and detail the interior tray.
11. Decal the body. I almost always use decals from http://www.slotcars4u.net on my kits. These decals are very strong and well made. They are also researched extensively and are not a generic decals for a car. Tim Millward is the gentleman that does these decals and he takes some serious pride in his work. He utilizes an ALPS printer that produces amazingly decals. He coats his decals in Future to ensure you'll have a trouble-free installation. He also includes fabulous instructions that include some of the history of the car you are modeling.
12.Final Detail. At this stage, adding trim paint around windows, vents, windshield wipers, and gas caps is a good idea if you are painting them. This way, the final clear coat will protect these areas. If you are using Bare Metal Foil, I recommend not doing so until after the clear coat, as it tends to fog and dull if you coat it.
13. Clear Coat the body. I use two coats of clear depending on my needs: Duplicolor Clear Lacquer and Future. It has changed names several times. I have a Tip & Tricks article elsewhere on my site about how to use it. A great Internet resource has surfaced that describes the different branding of this product. Check it out: http://www.swannysmodels.com/TheCompleteFuture.html
14.I like to use a clear drying craft glue like Elmer's white glue or Tacky Glue to glue the glass parts in. A good applicator is a normal toothpick, allowing you to put a very small amount on at a time. Craft glues clean up easily with water later if you accidentally place it somewhere visible. Be sure to allow the parts to dry depending on your installation method.
15.Interior Assembly. Often I'll use a low-heat glue gun to glue my interior trays in or I'll use the craft glues mentioned above. They are easy to remove later if needed. Only a little dab is needed, so don't empty the gun or cover each seam of the tray as it is not necessary, and only makes later disassembly difficult.
16.Chassis Assembly. Screw the chassis assembly to the completed and assembled body shell. Be sure to check for proper fit and that the tires spin freely inside the wheel wells and that the guide blade is able to rotate properly.
17.Race it! All of my cars see the track. I don't build cars to be shelf queens and believe that if I've spent this much time building something I want, I should at least take the time to run it. Remember, this is still a toy!
