Hex Drivers

[Perrotoro]

I've been back in slots for nearly 2 years now and have messed up several 0.9 mm hex drivers and/or hex set screws. It seems to be moreso the screw than the driver, but not always. Is there a better practice I should use to avoid this? Am I just too heavy handed or is this a common occurrence regardless of the experience level?

Thanks,
David

[HomeRacingWorld]

Well....I have done my fair share of damage. And most times? Yeah, it's me. Heavy handed is the correct term. BAD habit of over-tightening. I picked up one of those torque limiting drivers, I think mine is the Sloting Plus. Have to say...it helped me :dance:

[SuperSlab]

I would admit to similarly mangling setscrews a few times. My most common cause of this is not ensuring the driver is FULLY seated in the screw head. This typically happens with setscrews that are accessed through the tyre as on most CB Design wheels

[chappyman66]

The other thing that helps is grinding a very small flat on the axle. The screws will hold better on the flat than on the round, and it takes less torque to get them tight. And no...it doesn't unbalance the axle to any noticeable degree.

[waaytoomuchintothis]

I'll join in on all the advice given here. I will add that there are lots of cheap Chinese Allen wrenches out there in the world and they will round off with almost no torque. Chinese fasteners and other tool items can make you think its your fault.

I once had a box of specialty screws for wood construction that were supposedly high quality, and they were junk- as close as you can get to outright fakes. They were supposed to be a new kind of thread that could stand lots of rough handling. When I returned them, the vendor said he had been taking these things in for weeks and showed me a box nearly full of packages of these screws he had refunded. He also said he couldn't return them, as Chinese goods made for Western markets are endlessly complicated to trace back and no one even tries to do it.

[ConrodJo]

I use one Slot.it small torque driver for some years and one other large one by other maker.
Both of them lasted a long time and I never round off any screws with them.

Also use two cheap Chinese ones with blue handle in my small kit when traveling, they seem okay, I just try not to do up too hard.
Very occasionally get a grub screw which doesn't seem to let the driver seat properly so I throw that grub away.

I make many cars and hardly ever have a problem, so I think there is more user error than people care to admit.

[ConrodJo]

I use one Slot.it small torque driver for some years and one other large one by other maker.
Both of them lasted a long time and I never round off any screws with them.

Also use two cheap Chinese ones with blue handle in my small kit when traveling, they seem okay, I just try not to do up too hard.
Very occasionally get a grub screw which doesn't seem to let the driver seat properly so I throw that grub away.

I make many cars and hardly ever have a problem, so I think there is more user error than people care to admit.

[munter]

Slotting plus tools for me too...bought a spare tip but havent needed to use it after about four or five years.

A of lot of set screws are made for a one time use...so I have a life time supply from eBay.
I like the black ones as they are more likely to fail than chop out your hub thread compared to a stainless steel grubscrew which are also available.

[RichD]

There are four possible reasons for stripping the set screws or rounding off the driver. First there are screws that are not hard enough and will strip very easily, I always replace those with high quality screws from Slot Car Corner. Many of the available wrenches are not properly heat treated and will easily round off, on the other hand some wrenches are hard enough, but are too brittle and the tip will snap off if you are not very careful. Finally the driver must be a good fit for the screws, if the tip is just a little too small the risk of damaging it or the screw would be greatly increased.
Wiha and Wera make good drivers for a reasonable price. You can reduce the odds of having a problem if you use a torque limiting driver. For years I used the orange ones that Slot.it sold, those had a tip that was a good compromise between hardness and resistance to breaking off. Those drivers have been replaced with a newer version that I have not tried. My go to wrench is the torque limiting model from Scale Auto. In some cases you may need a wrench for hubless wheels that require a longer than normal shank or something that can poke through a tire that has been glued on the wheel. Some wrenches have replaceable tips, if you get one of those you might also order spare tips.