I've had one break from over tightening before, that is why I ask.

This has been a fun post to keep up with, your aren't hurting anyone or wasting anyone's time but your own.

So damn the torpedoes, full speed ahead!

I have witnessed dual set screw pinions fail in this manor on more than one occasion. Even if you're able to drill the hole, tapping the threads is going to be the problem. A tap that small will not be able to handle cutting threads into a hardened material. They just are not designed to do that. See this is where it becomes abundantly clear that you are strait out of school, and working as a consulting engineer. A real engineer understands design limitations, and that there is a process to working within those limitations. The real engineers have already figured out that a tap can't be made that small, AT A REASONABLE COST, that can tap into a hardened material. So if a real engineer is designing something that needs to be hardened, and have a set of 4-40 threads. He makes the threads before he hardens the material.

Also as far as having a few pinions sitting idly by. They are $4, I mean come on. And don't pull this I love the challange BS. If you really loved the challange you would set your goals a bit higher than "I wonder if I can do something that has already been done (make your own pinion gear)" Oh I bet the machinist where you work just love you.

I would try using a Forming Tap/Roll Tap or a Thread Mill in this application.


I would not attempt making my own pinion, I leave it to the people that specialize in gear cutting or hobbing.
If you have access to the specialized equipment and the time to learn the manufacturing procedures it could be interesting to you.

Well bud I'm going to design and make my own and actually I am quite popular out on the floor because they agree with me that a single set screw isn't the best solution for it because we used to use some toolin that only ha a single set screw and often would easily fail and trust me bruh I'm not a fake engineer as your implying but everyone has an opinion so I'll attack my problem as I see fit and since they are some others that seem to have genuine good ideas I'll listen but hey that's why I never said my idea was the best thing ever just an option

I am kind of amused by all of this

Well makin th pinion blank is the easy part and heat treating it is easy as well the real issue becomes in actually cutting the teeth and I say that because I don't have the set up for cutting te teeth so I'd have to send that somewhere to be done but im definitely kicking the idea around of giving it a whirl...anything can be made to work its just a matter of does the person doing it see potential gain and I see it as an opportunity to test out some things so maybe I will try it

Here is an idea. Lets stop the bickering back and forth and refrain from posting until the OP has proof (pics) that they did it. The OP is no longer asking a can I do this, his mind is made up. Therefore just do it...

I think this is an enormous waste of time solving a problem that doesn't exist, but I will try and help

Most pinion gears have a 5-40 set screw in them and you will need a #38 (.1015) tap drill. Any carbide drill will have no problem drilling through the pinion. You will probably need to use a thread mill to get the threads into a part that hard.

" Oh I bet the machinist where you work just love you.[/QUOTE]

I'm not taking sides at all, but that was a good one..lol

You can go ahead and spend all this time and effort to design something completely unnecessary. I have been in this hobby for 20+ years and the only time pinions come loose is when the set screw is not tightened enough. I have run nothing but RRP aluminum pinions for the last 5 years. When I bought all the pinions (a bit of money for the whole set) I cleaned all the set screws and pinions with solvent, put a drop of blue loctite on each set screw, and put them on a pinion gear rack. I have never had a pinion gear come loose. The key is using a high quality wrench, and always double checking that the pinion is tight. If a pinion has been allowed to vibrate loose on multiple occasions, the threads will begin to degrade. The key is once the threads are worn, the pinion will never stay tight. One set screw, two set screws, or twenty. One set screw is what the situation calls for, so one set screw is what is used.

What piece of equipment at your place of employment had only one set screw that failed. What was the job of this part?

What car are you having the problem on? On 1/10 I like to use the losi pinions, they seem to be alittle thicker, but on 1/8 I like the tekno because their set screws are bigger. Not all pinions are created equal.

Nobody stopped to ask if the motor has a proper D shaft, or if the motor mount was bent. Instead y'all feed the troll ( not a bad thing, made for some lunch time amusement).

Boaring bar made by kenametal had a single set screw in it was rather amusing to watch it fail and Actually to be honest I never even stopped to consider that the motor shaft or mount could possibly be damage and it's an 8th scale mamba monster motor and my buddy had a similar issue with his mamba XL motor n pinion slipping so he bought a non hardened gear and drilled it out to have 3set screws grabbing the motor shaft same concept I use on my non hardened pinion...and machining the gear blank is easy the teeth not as much but it can be done And I would agree not all pinioned are made the same the one cheesy Lhs sold me a carbon steel pinion once as a hardened one or I should say tried to anyway I wa like bud no way is this hardened look at the color difference between this one that definitely is and the one that's not but I also feel like I can be more selective about what materials to use if I make my own

Bah, won't work unless you flatten the other side of the rotor shaft.

1.) Get new RRP pinion. Make sure it's a new setscrew. Set screws do wear out, and they do need a sharp biting edge. I allways keep fresh setscrews on hand.

2.) Spray brakeclean on pinion, on setcrew, on motor, in your eye. Get pinion extra clean.

3.) Put a little blue or red threadlock inside the pinion shaft hole. Rub it around with a wrench. Shaft hole, not the screw hole.

4.) Put a tiny amount, so thin you can't tell the color on the set screw

5.) assemble, let dry overnight

6.)?????
7.) Profit!

Red threadlock is a breeze to get loose. Use a micro torch.

Why not just use a Hyper 9E pinion, comes with 2 set screws AND the holes to match
http://www.nitrohouse.com/Pinion-Gea...9E_p_6529.html

I have never seen this one I knew there had to be a 5mm shaft with what I want somewhere but now I have a drawing of it and am ready to make a 3d cad model so I now intend to see this through bUt definitely going to look into that pinion you recommended so I had another idea today while talking with a machinist and then we were saying why cant I make a socket headed cap screw to fit it, ie machine a gear and have it to have a counter sink for part of socket head cap screw to sit in I mean it's not a terrible idea at first glance but clearnence I for see being an issue and I definitely don't want the head hitting the spur gear