Product Review - Hudy Tire Truer

Hudy Tire Truer

Before I tell you about the Hudy Tire Truer I want to discuss a principle in slot car racing. All tracks run with limitations on ground clearance. This is a needed restriction. If the cars are too low to the track the cars will drag on the track or the braid at times. This rule is sometimes in conflict with a racer wanting to make his car handle better. Here is the principle...the lower the car is to the track, the better it is going to handle. This is because the center of gravity is lowered. If you think a few hundreds of an inch will not make any difference you might as well quit reading this and go racing in a mud bog with a corvette. It makes about as much sense to drive in a mud bog with a car that is too low to the ground than it does to race with a slot car with higher ground clearance than you must have.

There are two ways to lower your car to the track. One is by reducing the ride height in the front with the guide flag. Reducing this end of the car is not what this review concerns. There are products we can discuss for that purpose at a later date. To reduce the ground clearance in the back you must do it in one of two manners. One is to raise your rear axle thus making your car lower. The way I want to discuss is the second option. This is by reducing your tires in diameter. To do this you have to remove rubber from the tires. I have seen people do this by running their car with the tires on and laying the rear tires on a block covered by sand paper. This does work but it can be hard on your motor and time consuming plus it is not all that accurate. The second way is with a small lathe. I have seen this done and it works quite well. It is quick, it will lower your stance and trues the tires at the same time. If you have a small lathe it is a great, but it is not a really portable tool you could take to the track with you. If you do not have a lathe you are looking a $500 or better investment to get one. The third way is with a commercial tire truer for slot cars. There are more than one brand of tire truer out there but I will look at the Hudy Tire Truer for this review.

Hudy has an extended line of products for the RC car racing industry. Their products seem to be quite well made and well thought out. The Hudy Tire Truer for slot cars is the same. It is well designed and executed. It is small, portable and looks very professional. The Hudy Tire Truer works on one tire at a time. It would be nice if you could do two at a time so the tires would be perfectly matched. This not being possible Hudy has done the next best thing, but that will come later. The Hudy works with the tires mounted on an axle that spins driven by a motor. The tire will come in contact with a drum covered with sand paper which is also spinning. You adjust how close to the drum the axle (and thus the tire) is until the two come in contact and rubber starts being removed. This is achieved by turning a screw. If the screw was not in place the drive belt on the pulley that turns the axle would pull the tire into contact with the sanding drum. The screw holds the tire away from the sanding drum. As you turn the screw the belt is allowed to pull the axle closer to the drum. This is done until the tire comes into contact to the drum. At that point you let it sand until it has taken as much rubber off and can't take anymore off. The sanding drum will remove rubber from the tire until the screw is preventing pressure from being applied to the tires. At that point you turn the screw some more allowing more rubber to be taken off if the tire did not have rubber taken off all the way across the surface of the tire. You continue letting the tire closer to the drum until this is achieved. At this point your tire is trued. Your next tire will need to be the same size as the tire you just trued so you set the position on the Hudy Tire Truer so it will not take the next tire to a smaller position than what you have done to your first tire. This is done by a second screw. First turn the truer off so the drum stops spinning. Then turn this screw in until it makes contact with the location the current tire is set at. It is important that you turn this screw until it makes contact and do not go farther. If you go farther you will be lifting the current tire away from the drum. In order to have both tires trued and the same size in diameter you must set the second screw at the point where it touches, no more and no less. Now that this screw is set you turn the first screw to back the original tire away from the drum. Remove your first tire and put your second one on. Turn the truer back on and continue as you did with the first tire. The second screw you set will not allow the axle to move closer to the drum than the first tire was set. Once you get this tire sanded down to the set point of the second screw you check to see if this tire had rubber taken off all the way across. If it did you are finished. If not then you back out that second screw and continue sanding by using the first screw to allow the axle closer to the drum. Once you have this tire completely trued you set the second screw and go back to the first tire to finish up.

This is a simple process once you start. It will allow you to have tires that match in diameter plus are true and will not have a slight wheel hop to them. Just because a tire is new does not mean it is true. Even new tires should be taken to the tire truer.

Now more about setting the ground clearance on the rear of your car. Here the purpose is not just to true the tires but to take away as much rubber as is needed to lower your car. If your car is riding with excess height you will want to measure your tires with a caliper. You then will use the tire truer to remove a desired amount of rubber. You can check the new diameter without removing the tire from the truer with the calipers. Once you get the tire where you want it set the second screw to make sure the next tire is taken down to the same size. Take your tires off the truer and put them back on the car to check clearance. If it is still too tall repeat the process over again. Do this until your car is at the desired ride height. Once you have done this you can measure the tires with the calipers and any future tires can be taken down to the proper size based upon this measurement. This will allow you to turn your tires down to where you want them in the future with no trial and error. Remember, when you are taking rubber off tires it is better to do it slow than quickly. You can always take more rubber off, but you cannot put it back on once it is off.

How well does this unit work? It is a smooth as a babies bottom covered with possum grease. It actually does a really good job at what it was designed to do. The truer does not take rubber off as quickly as a lathe, but it cost much less than a lathe and is actually small enough to carry with you. The unit comes with its own travel case and is fairly well protected unless you deliberately throw it down or do something truly destructive to it. It will work with 3/32 or 1/8 axles as it has an axle blank for both. The 3/32 is a 1/8 axle that has been turned down to 3/32 where the tire is mounted. The Hudy Tire Truer does not come with a power source. You need to connect it by alligator clips to some source for power. It is suggested that you use a 12 volt power source. This is easy enough to find and cheap enough to set up. To be transportable you may want to look into rechargeable batteries. I used one with a 6 cell sub-c battery pack from an RC car set up. This was less than 8 volts but it still worked fine until the battery pack started discharging. I was able to do some serious truing on several sets of tires before the pack discharged. When considering how small these battery packs are it makes the entire unit very portable. Due to legal issues that could occur, let me emphasize, I do not recommend using less voltage than the manufacturer recommends. I only pointed out the reduced voltage because of my own experience with one. The only problem with using one of these little beauties at the track is you might have a number of people asking you to true their tires.

Now the negative side. It is not much of a downside. It was a problem that affected the unit I tested and was easily corrected once it was discovered. The Hudy Tire Truer I tested was an almost new one. It had trued maybe two sets of tires at the most. I ran seven or eight pairs of tires through it with no problem. Then I decided to take a set of tires down to a smaller diameter. Everything worked fine until the tires got to about 0.690”. It was at this point the tire I was truing started hopping. After investigating of the situation it was discovered that one of the pulleys was misaligned from the factory. The pulley that drove the tire was bumping the pulley that drives the sanding drum. This was the cause of the hopping problem and only showed up when the tire diameter got small enough for the two pulleys to overlap. The solution was to loosen one allen screw and move the sanding drum pulley into proper alignment then tighten the allen screw back down. This then allowed the tire to be turned down to 0.63” without any problem of the two pulleys touching. The test was abandoned at this point as we felt the problem was rectified.

The clean up on this unit is a must. If you do not clean it after every use you will have rubber that is now like a fine powder all over the place. The clean up takes a while as there are a lot of little nooks and crannies the powdered rubber can get into. You simply have to be patient and do the best you can. The truer is on a base which it can come out of allowing you to clean underneath with ease.

This is a dandy little machine that will work well. It is easy to use and with a little caution in its use it is pretty much fool proof. It works as advertised and I would recommend one for anyone who is serious about slot racing. The benefits that come from using one of these is immeasurable.