12 replies to this topic

[Pablo]

What size tool fits this screw? .050" is too small and 1.5mm too big. Thanks.

 

Pablo

[Joe Maxey]

1.3mm should be the ticket.

[Pablo]

Thanks, Joe. Sounds like a good guess. Hopefully Ace Hardware will have what I need.

 

Just kind of surprised it isn't a standard size. i can't find any slot car source for such a tool.

[Bill from NH]

If Ace doesn't have it, check with your local auto parts dealers. Amazon and Grainger both advertise that size.

[Pablo]

Swiss corrected me, .050" is about 1.3mm.  

Maybe I need about a 1.4mm?

 

The fact remains these screws will not fit a 1.5mm and are way too big for a standard .050".

With an .050" tool I screw one into an FK motor to test, the threads are perfect.

But when it comes up flush to the can, the tool can't get a bite.

Yes, I've tried two brand new .050" and 1.5mm tips.

 

Tomorrow, the fight continues...

[Bill Seitz]

I've discovered that all .050" hex bits for slot car tools aren't created equal. There are some that fit screws well and some that don't, and even some that are oversize. 1.3mm seems to be the metric equivalent of .050". I don't know whether the differences I've found are the result of tolerance on .050" bits or 1.3mm screws masquerading as .050", or 1.3mm bits masquerading as .050".

 

Best screw fits so far have been with Koford bits; poorest with Parma. The difference in size is only about .001".

[Bill Seitz]

Mid-America claims these screws use a 1.5mm bit, and they sell such a tool. Under the tool's description, it states this is also the JK mounting screw size. JK also has a 1.5mm tool indicated for the motor mounting screws.

[Pablo]

I tried three different 1.5mm tips, none fit. Period.

[rmjlmartin]

Just like the hex bits, screws are also not all created equal. If those are the same motor screws that come on the brushless RTR cars, they're not the best quality. Or at least mine weren't.

 

I've been using these- https://monsterbolts...911e23d48&_ss=c

 

They're very nice quality. Monster Bolts list a lot of their screws on eBay, too, if that's easier.

[Pablo]

Thanks for the inputs, guys. I got a hold of Roger and his answer was simple. They use a 1.3mm head.

 

I know the difference between .050" and 1.3mm is minute.

The reason is, in actual practice, the jump from .1.27mm/.050" to 1.3mm//.051" is enough to make it fit.

 

So now I have to order a new tool   which is something I'm good at.  

I will let you know when I get it but I'll bet on Roger.

 

Joe Maxey wins the cookie. 

[Bill Seitz]

Mid-America doesn't sell a 1.3mm bit or tool. Wiha sells a 1.3mm tool, but also indicates this is .050".

 

I'm glad I looked at this thread which sent me investigating motor mounting screws. My motor mounting screw experience to this point has been with the Parma self-tapping screws used in the plain holes on C & D cans and some F cans. These use a 5/64", also indicated as 2mm, hex tool. I did purchase some of the metric thread mounting screws for the threaded holes on F cans a while back, forgotten what brand, but haven't used any yet. They're significantly more than .050" hex, more than .001" bigger, but smaller than 5/64-2mm, so they've got to be 1.5mm and will need a tool.

[Bill from NH]

I bought Phillips head screws for mounting FK and F050 motors. This stopped me from collecting allen keys that would be seldom used. I threw away those crude black screws Parma included with products. My first wing car chassis in 1970 had 2-56 screws for mounting a D-can motor. After that, I always soldered in C and D cans. I had no aluminum or plastic chassis, but I once was going to build one with popsicle sticks or 1/16" plywood.

[Pablo]

Wera wrench arrived today, it mikes at .051" and fits fine.

Strange how a thou or two makes all the difference.