Even with the same resin material, there is naturally a difference in quality and durability between modern materials and the materials used when the old car was still in service due to the evolution of the material, and even considering deterioration over time, the resin parts for old cars are more delicate and must be handled gently.Caused by micro-cracks caused by UV lightAnd it’s easily cracked, broken, or worse.It’s missing.It is often the case. Here, the big brother of the recently popular Honda CT125!?The CT110 is a genuine CT90 frame cover that is also the big brother of the CT110.Repair and reproduction of missing partsI did.
- 70’s resin parts are mostly made of ABS material
- Used for the master type because the shape was the same as the older parts
- Molding with “Plastic Nendo”.
- Plastic Repair” for adhesive filling of missing plastic parts
- Boil the plastic clay in a pot to make it soft.
- Master type = Reproduction of shape by pressing against the reproduction source
- Set a duplicate mold to the missing part = fixed and filled with plastic repair
- Duplication repair jointing completed
- The “beveling” process is a daring way to widen the wound.
- If you want to look at increasing your overall strength.
- Once the color match is set, the finish is perfect.!!
70’s resin parts are mostly made of ABS material
This is a genuine frame cover for a 1974 Honda Trails CT90, the predecessor to the Honda Trails CT125 Hunter Cub and CT110, which had a different graphic design and manufacturer logo for each year of the CT90 era. The ABS plastic material appears to have deteriorated over time.
Used for the master type because the shape was the same as the older parts
The frame cover was completely missing the fastening fixture around the left rear, where it covers the carburetor. It was lucky that the decal describing the handling of the carburetor was just barely safe when riding in a high altitude area. Even though sleeve washers are used to protect the parts, repeated tightening on the bolts often causes cracks to radiate from the fixing hole area. I would like to repair and regenerate it, including such anxious elements, but …….
Molding with “Plastic Nendo”.
I stumbled upon it while strolling through the craft section at Home Depot.!! It’s fun to pass the time at the home center, where a variety of interesting new products are being introduced. This product is a “plastic nendo” that can be used as a molding material because it softens when soaked in boiling water. It hardens again when cooled, so it can be used repeatedly.
Plastic Repair” for adhesive filling of missing plastic parts
Daytona actively handles a variety of chemicals and maintenance tools. For this missing part repair, I used Daytona’s Plarivair. Since it is planned to be painted, we dared to use the yellow Plarivair that improves the “red color” of the paint to repair the molding filling. If the color is hard to hide, the color of the base will affect the finish. This Plarepair has a special high performance in the adhesion of ABS and acrylic resin, but it is incompatible with the PP system even if it is the same resin.
Boil the plastic clay in a pot to make it soft.
Put the plastic nendo into the boiling water. How many pieces should I put in??I wasn’t sure so I threw in more. The great thing about this plastic nendo is that it can be reused many times. When it is warm and soft, use chopsticks to remove it from the hot water, press the plastic nendo onto the part of the master part that you want to replicate, and mold it so that the nendo goes around the edge.
Master type = Reproduction of shape by pressing against the reproduction source
Press it into a shape that goes firmly around the cutout area, and press it firmly with your fingertips so that air bites do not occur in the flat area. Wait for complete hardening. As it cools, the plastic compound will begin to harden. When it hardens to a certain extent, remove it, but be careful not to peel off the paint film of the original part. It is also good to spray silicon spray as a mold release agent beforehand. The part to be replicated has a fastening hole, so press your fingertip against the hole when making the mold to make sure the glue goes around the hole. It’s best to keep the holes about the same size, because if they stick out too far, it will be difficult to remove them.
Set a duplicate mold to the missing part = fixed and filled with plastic repair
Set the plastic mold on the missing frame cover. At this time, it seems to be easy to set the mold in place by using a small shako. If the mold shifts during this process, it will cause failure. You can also use gummed tape to support the mold. Let’s proceed with the work without panic. The game is decided by the arrangement. In this case, I used the “sprinkling method”. The powder of PLARIPAIR was poured into the duplicate mold in advance, and the powder was carefully spread around the mold. Then, I poured the plastic repair liquid from the syringe while letting it soak in slowly. The trick is to spread it evenly over the entire surface. When the liquid soaks in, it changes from bright yellow to milky yellow and hardens. Wait for a day and a night in this state for curing.
Duplication repair jointing completed
After a day and a night has passed, confirm complete hardening (it can be judged to be completely dry if there is a light poking sound with the tip of a screwdriver) and remove the plastic nendo. If it is difficult to remove, you can cut the duplicate mold with nippers. The yellow part is the part that was repaired by plastic repair. Since it was a thick part, the missing part was degreased with acetone and cotton swab beforehand. If you are worried about the strength, you can make the bonding surface uneven in order to expand the bonding area.
The “beveling” process is a daring way to widen the wound.
Since there were cracks other than the repaired part, I processed the V-groove on the back side of the cracked part with a rheuter and repaired it with PLAREPair. If the part does not have thick walls, the plastic repair will cure in about half a day. The bolt tightening area is prone to small cracks. I used a rheuter blade to dig a V-groove on such a crack, and then used Plarepair to repair it.
If you want to look at increasing your overall strength.
If you simply want to make a thin reinforcement, you can use glass fiber like surfacing mat, but I don’t recommend surfacing mat because it is not strong enough. In this case, I used carbon cloth for the strongest reinforcement. On the back side of the reinforcement area, use a belt sander to remove the paint so that the poly resin can easily stick to it. Carbon cloth is ideal for surface reinforcement. Regardless of whether the reinforcing fiber is glass or carbon, polyester is a good resin to use. If you use the wrong amount of hardener, it will not harden properly, so be sure to mix it carefully.
Once the color match is set, the finish is perfect.!!
Now it’s time to finish the paint job, but we have to make the color to match the condition of the faded used parts. It is difficult to match the color to the sun mech, so this is a job for professionals. Instead of spraying the paint to make it shiny, we tried to make it look like it was faded. We adjusted the spraying pressure and the amount of paint dispensed from the gun nozzle several times as we worked. The paint was applied to match the overall atmosphere. After the work was finished, I used a dryer to dry the paint for 30 minutes at 50°C setting.
The “Hunter Cub” series, as it is commonly called, began with the CT200 equipped with an OHV engine and has continued to be produced for about 35 years, evolving from the CT90 to the CT110. The latest CT125 has evolved from a carburetor to fuel injection. It is even easier to handle and has evolved into a very popular model.
cooperation in photography:Model Create Maxi
- Point 1・Workability is improved by using a cassette stove.
- Point 2・The plastic repair layer becomes thicker depending on the shape of the repair area, so wait for it to fully cure.
- Point 3・When you want to increase the surface strength, it is better to use FRP or carbon (CF) cross fiber together.
Regardless of the model, new or old, you may be disappointed by cracks or missing plastic parts when you are enjoying your motorcycle life. A fall or even a slight injury can cause serious damage. The plastic parts can be repaired and rebuilt with PLAREPAIR, a plastic parts filling adhesive.
The part to be repaired here is the “frame cover” of the series called Honda Hunter Cub. It is a familiar part in terms of design, but it is a long-selling model, and this part is for a model produced in the mid 70’s. The material seems to be ABS resin, but we thought it needed a high level of repair because there were some parts that were “missing and lost”, not just cracks and breaks, so we asked a professional to repair it. Let’s take a look at how it was done.
What should I pay attention to in advance when repairing such parts??I asked Mr. Itabashi of Model Create Maxi who asked me to repair it.
I think it is not difficult to repair the missing part, but if you want to reprint the design of the missing part, the most reliable way is to use the part that is not broken and copy the shape of it. So, we prepared the genuine frame cover for CT110 Hunter Cub which has almost same shape, and we decided to “make a copy of the missing part by plastic repair” using the copy mold.
It is important to note that the parts should not be removed from the mold after the plastic repair has been curing for 2-3 hours. It takes more than a day and a night for the thickly filled (raised) part to fully cure. In short, the product will be distorted and deformed if it is not removed from the mold after it has fully cured. In addition, it is difficult to cut and shape the product with a file before it is fully hardened, and the product can be easily deformed and destroyed depending on how much force is applied.
No matter how much it is repaired, there is a big possibility that the parts which are deteriorated with age will be cracked again. So, when the shape is restored extensively, it is better to reinforce the back side. This time, we decided to reinforce the wide area by attaching carbon cloth with poly resin.
A long time ago, broken parts would have gone in the trash. Even if it was a different year, if there were parts for later models that could be bolted on, the usual solution was to replace them. However, nowadays, the meaning of words like “original” and “appropriate for its age” has become more important, and repairing them has its own significance. In light of this modern understanding, “repair and reproduction” has its own significance.