Rebuilding the 1/32nd Scale
Scaleauto Porsche 935 J

Part 3

The Finishing Touch

The final step of this tuning process involves tire gluing & truing. Using Paul Gage tires is a good choice and they fit the wheels very well. Yet there is always a little stretching involved and that means they need to be sanded or trued to the wheel. It also includes gluing the tires which many feel is a critical step in performance.

Glue or Not To Glue?

Ask almost any advanced enthusiast and they will tell you that most any tire should be glued to the wheels. It keeps the tire secured to the wheel and helps prevent it from rolling off the wheel and causing hop when you are digging into those corners. If you like a faster motor in your models, it also helps reduce/eliminate expansion. Take a car and place it on your track and lift the rear in the air. Now give it full throttle. If the motor in the car is powerful enough you should see the tire actually expanding, almost to the point of coming off.

It is easily enough accomplished using the right adhesive.

What is the "right" adhesive? For Paul Gage urethane based tires I use clear nail polish. It secures the tires very well but leaves you the option of easily removing them WITHOUT damaging the tire.

Other enthusiasts do not agree that this method holds well enough. This might be true for pure silicone tires but on urethanes it does the job for me. The other option is using super glue. That is a very loose term applied too often however. There are so many different types, not just the cheap tubes you find at the local mart. Fast setting liquid super glues are not advised. They do not leave you anytime to work with the tire and can be a very messy and frustrating experience.

If I use a stronger glue, the brand I have used that works the best is Cloverleaf Racing IC-2000. This is blended for working with tires and many racers use it exclusively.

Like any other step we have followed, you do it the way YOU feel is best. I will show you how I like it and you can either try it or not. If it works for your purpose then it is the right way to do it.

 

Mounting The Wheels

This part of the article is Step 3 of a project. You could have performed this step first. However, I like to do this last because handling the wheels and tires during the gear setting process can sometimes require the removal of the tire.

 

I also wanted to take the opportunity to show you how to remove wheels that have had the tires glued on. It can also apply to those times when the car you have has already had the bushings glued in place and you are just performing a tire swap.  

Since we have glued one set of bushings into the chassis, we need to use a second set in the machine. That is fine because you should have a second set on hand just for these times.

Tire Truing

No matter if you glue or not, or the method you used, it's time to true these tires up. Nothing seems to transform a model from bad to good faster than truing the tires.

As with almost all the other steps we have covered, the techniques I use will vary greatly from others you might see. There isn't a wrong way to accomplish this as long as the end result is a tire that is as round and true as you can get it.

Since we are dealing strictly with Paul Gage urethane tires, I use a very fine grit sandpaper to true them. I like this approach as it leaves a very clean and smooth contact patch.

 

I only sand one wheel at a time. You could do both but I am just comfortable one at a time. I am not in that much of a hurry either. Some have complained that these machines do not true both wheels at the same time evenly. This is true on all brands I have tested. Yet, it isn't always because the machine is defective. It is mostly due to the uneven tolerances we deal with. It is commonly seen on plastic wheels and stock running gear where the loose bushings and the slight differences in the mold of the wheel itself effect each side. Even the slightest thing from having tire material under your block or the amount of wear on the paper can cause it.

What matters to me is getting them true and this machine will do it. As the video shows, I just take my time until I have sanded the entire face of the tire and move on to the next.

***Quick TIP*** You can attach different grits of sandpaper using regular double sided tape.

Now we are ready to install our wheels and mount the inserts.

The final step to finishing this model off is to install the inserts in the wheel. With this car we are very fortunate because the inserts pop right out of the old wheel and fit nicely into the new one. I used the tip of an Exacto knife and they came out with no damage.

Use some of the clear nail polish and coat the inside of the wheel. Then press the insert inside and you are done. They fit pretty tight and you could skip the adhesive. I just did it to be on the safe side.

Before we begin testing we need to make sure and lubricate the areas shown above. I use the oil SCC has on hand but just about any plastic compatible oil will do.

 

As you can see we have a very smooth model now. The gears will break-in and smooth a little over time and you will want to add lead weight here and there to suit your taste and track conditions.

I hope this series of articles has helped some of you thinking about tuning. It was fun to transform this model into the smooth runner it is now. Tuning like this is really a lot of fun for me and I look forward to hearing about your projects in the future.

- Harry

Feel free to CONTACT ME about this article or the hobby in general.

Model Purchased From PowerSlotcars.com