How to Pin Resin :
To most people, Resin kits are a scary thing. Most resin kits aren't designed to be assembled like a plastic kit would as, more times than not, they are cast from sculptures that an individual might have sculpted in their spare time. Plastic kits are designed to allow for anyone to pick up a kit and build it without any issues. Resin kits are aimed at the other end of the spectrum, which is also known as the experienced modeller, and require 'pinning' to hold the kit together.
Don't let that turn you off though, because in this tutorial, I'll demonstrate 2 easy methods of assembling a resin kit (in this case, Rader Studio's Tyrannosaurus Rex resin kit).
What you will need : (sorry no picture this time around!)
- The resin pieces you wish to assemble.
- Brass rod and/or nails (diameter of these depends on the pieces you are joining).
- Cordless Drill and appropriately sized drill bits.
- Pin Vise and appropriately sized drill bits.
- CA Glue (Zap-A-Gap is ideal).
- A Sharpie or similar permanent marker.
- Modellers masking tape.
- Cotton Wool.
Step 1 :
Begin by marking the center of the first piece where you want to insert the pin into.
Step 2 :
Now take the Cordless drill with the right sized bit and drill about 2 - 3 cm into the piece. The size and depth of the hole depends on the piece itself. If it is a larger piece, then a larger pin is required to stabilise the join. This also applies to the depth. The deeper the hole (which will mean a longer pin), the stronger the join will be.
Remove any excess resin that might be sitting on, around or in the hole. This is important as the resin shavings can cause adhesion issues later on. Lightly sanding aroung the hole is a good thing to do as well.
Step 4 :
The hard part of pinning resin, is matching the hole on the second piece. There are two ways I do this. The first way (which is better for pieces that are abnormally shaped on the ends) is to take some masking tape and stick it over the end of the first piece, making sure that the edge of the tape intersects the center of the drilled hole.
Step 5 :
Now take a second piece of masking tape and stick it on top of the other piece of tape so that the sticky side is facing outwards. Now take a knife and make a small knick in the tape where the center of the hole is.
Step 6 :
Push the two pieces together so that the second piece of tape adheres to the second piece of resin. Now gently roll back the tape so it comes away from the first piece of tape and sticks to the second piece of resin, like so :
Step 7 :
With the tape now stuck on the second piece of resin, find where the knick in the tape is and make a dot with a Sharpie. This is where the hole will be required to be drilled.
Step 8 :
Remove the tape and drill out the hole. Again make it 2 -3 cm deep (depending on the size of the piece - if it's considerably smaller, drill a shallower hole) but pay attention to the angle of the pin once inserted into the first piece. Match the same angle when drilling into the second piece. Failure to do this will cause the pieces to not align correctly and ultimately create more work for you to do. It is also a good idea to make the hole slightly larger than the pin to give something I like to call 'wiggle-room' or some extra space it make slight adjustments when glueing (the closer you can get to a perfect alignment of the pieces, then the less work needs to be done later when filling the gaps).
Step 9 :
Insert the pin making sure it's cut a little bit shorter than the two holes' depths added together.
Step 10 :
Before glueing together, test fit the pieces to make sure that everything aligns correctly. If it doesn't, adjust the pin by bending it or drill out the hole some more. Test the fit again, and if it is OK, then move on to the next step, otherwise you can readjust the holes and pin again until it is right.
Step 11 :
With the pieces aligned as close as you can get to each other, apply some CA Glue to the pin and surrounding areas of the pieces. Just use drops around the piece, there is no need to drown it all in glue!
Step 12 :
Wait for the glue to fully cure and then move on to the gap filling.
Step 13 : Alternative method for marking holes.
For the next part of the tail I am assembling here, I'll show you the other method I use to mark the second piece for drilling. This method works best when the two pieces can be pressed flat against each other. First, take the drilled piece and fill the hole with cotton wool so it just sticks out the top a little bit, like so :
Step 14 :
Colour the end in with the permanent Marker.
Step 15 :
Take the second piece and press them together so a couple of seconds.
Step 16 :
Pull the pieces apart and the second piece should now have a black mark where the next hole should be drilled. Don't forget to remove the cotton wool from the first piece too. Now return to steps 8 to 12 of this tutorial and drill the holes then mount the pin.
There you have it, 2 easy ways to pin resin kits together. I've done this tutorial using a Dinosaur kit, but the principles remain the same for any type of resin kit. Once assembled, you'll need to fill the gaps and such like you would with plastic kits, but that's another topic for another day.
Resin kits aren't as difficult as they look, so do yourself a favour, buy one and give it a go - you'll be suprised how easy they can be.