Dear customers,

our support is repeatedly confronted with similar questions which naturally arise in the context of RC-Cars and bolts, screws and such. Therefore we have gathered the "Frequently Asked Questions" for you. If you do not find an answer for your issues here feel free to contact support.

► What screws of my rc-car can I replace with a screw-kit?

► What kind of screws are being used for the screw-kits?

► I cannot find any tapping/cutting screws in the kits. Did you forget them?

► What materials are the screws made of? What does "A2" or "12.9" mean?

► What exactly is so much better with titanium grade 5 screws compared to grade 2?

► Do the screw-kits come with tools?

► What is the advantage of hexalobular/6lobe/(known as TORX®) screws?

► Why are there only screws of M3 and above in the hexalobular/(known as TORX®) kits?

► Why are there hexalobular/(known as TORX®) M6 galvanized steel screws in 8.8 and not 10.9 in the kits for huge models (1/5 and 1/6)?

► How are the screw and kits packaged? How does a a screw-kit look when ready to ship?

What screws of my rc-car can I replace with a screw-kit?

Given you choose the fitting kit for your car you will be able to replace all screws of your car. Depending on the model the kits contain screws of this sizes:

Note: What is not in the kits!

There are connecting elements and fasteners which are not officially normed but specific makings of the individual producers of the models. Those we cannot offer. What exactly those elements could be we have explained here.

What kind of screws are being used for the screw-kits?

In our screw-kits we exclusively use hexagon or hexalobular screws (known as INBUS® and TORX®).

Those are superior to slot and cross-head screws by having much better power transmission and thus reduce the danger of damaging screw-heads or car-parts.

I cannot find any tapping/cutting screws in the kits. Did you forget them?

If in the original model of your car there have been used those tapping/cutting screws we will have replaced them with better, i.e. threaded, bolts in our kits. These have adavantages:

• They hold better (as long as the hole has not been worn out).

• The narrower thread pitch, and with it bigger thread-surface, lead to better grip of the screw.

What materials are the screws made of? What does "A2" or "12.9" mean?

Stainless steel screws

Our stainless steel screws are made of so called "A2-70 stainless steel".

A = Austenitic steel
2 = High corrosion resistance. Partly acid resistant. Chrome nickel-chromium alloy.
70 = Minimum tensile strength of Rm= 70N/mm².

I.e. the screws are cold worked metal, non-rusting stainless steel.

High tensile steel screws

Our steel screws are alloyed with additional tempering. The blackish to brownish appearance originates from chemical treatment to increase corrosion resistance.

The designations "10.9" and "12.9" indicate the steel's strength class and minimum tensile strength.

For example: A typical cylinder screw M3 x 12 mm class 12.9

The value "12" indicated the minimum specified tensile strength. To calculate it the value needs to be multiplied by 100.

12 x 100 = 1200.

Hence the minimum specified tensile strength equals 1200 N/mm².

Another value is yield stress tolerance or elastic limit which is calculated by multiplying the first and second indication values with 10. I.e. 12 x 9 = 108. 108 x 10 = 1080. Thus the yield stress limit is 1090 N/mm².

Altogether this results in the fact that a tiny M3 cylinder screw of 12.9 class steel can withstand permanent stress of 490 kg (1kg = 9,81 N).

What is so much better with titanium grade 5 in comparison to grade 2?

Due to its higher tensile strength is lasts longer during driving and withstand more force during assembly. Also the risk of cam-outs is significantly reduced.

Do you include suitable tools to your screw-kits?

Yes, we add a wrench. However, only for hexagonal sockets.

In case you need high quality tools please refer to our offer of PB Swisstools.

What is the advantage of hexalobular /6lobe/ TORX® sockets?

It provides optimal torque transmission. The design allows for highest torque application. The vertical surface also renders unnecessary the need for high pressure. Additionally the operating torque does not only apply selective.

The result is less wear and you can use the screws more often.

Why is it that in hexalobular/6lobe kits there are only screws starting from size M3?

The reason is maximal possible torque of the screw compared to possibly used tools.

Unlike hexagonal socket screws torque transmission is much better which results in less cam-outs and broken sockets. However, this advantage declines along the size of screws until it cancels out. For screws smaller than M3 there is no physical advantage compared to hexalobular/6lobe why we keep them out of the kits in favor of price-performance ratio of the kits.

Why are there hexalobular/(TORX®) M6 galvanized steel screws in 8.8 and not 10.9 in the kits for huge models (1/5 and 1/6)?

Again the reason is price-performance ration. For our own production the necessary number of screws is too little to justify the extra cost. Even in the big scale models only a small number of M6 screws are being used. If we were to use them in our kits those would become too expensive to be attractive.

However, the physical properties of maximum torque in M6 screws differs only from 16 to 14 Nm (approx. 15%) between 10.9 and 8.8 which we believe to be negligible.

How are the screw and kits packaged? How does a a screw-kit look when ready to ship?

We sort the screws by length and diameter and put them in organizer boxed which are shock-resistant.

For us this makes an easy to use "out of the box" experience which is only logical and tidy.

Kits up to 400 screws come in smaller box with six compartments. Kits with more than 400 screws come with 10.