Spline drivers - definition please?

[Jack Ryan]

I know this subject comes up quite often but I'm looking for some precision without having to purchase a heap of standards.

From this image harvested from the Internet:



The "spline drive", triple square and a double hex are of interest. In various places they are all called "spline drives" and 12 point drives. The triple square (XZN) and double hex are straight forward but it would help if tool shops and tool suppliers would not call them "spline drives" or 12 point drives.

Then we come to the "spline drive" in the image. To me, a spline drive has square teeth and is a driver for a spline bolt.



And it could be an inner spline or an outer spline. Is there something with triangular teeth like the image that is also called a spline drive?

So, what I am looking for is a definition or specification and a name that uniquely identifies each of these "spline drives".

Thanks all and love the Journal.

Jack

 

[dnschmidt]

Spline drive seems like an artifact of the past. I have a set of Xcelite spine drive 99 bits (interchangeable handle) and I've never seen a true spline drive set screw (internal like an Allen) bolt in my life. I bought this set in the 1970's so they might have been popular way back then.

 

[cgrutt]

Sorry not really answering your question but a while back a good friend who is a professional mechanic recommended a MATCO set of extra long flex end ratcheting wrenches. The ten-piece set (10-19mm) currently is priced at $625. He said it was hands down best set of wrenches he ever used and he has a very extensive collection. The set is spline drive both on the ratcheting flex end and fixed box end. I questioned him on why I would want a spline drive set and he said it works on pretty much everything. MATCO promotes it as:

• Loosen or tighten any 6 point, 12 point, spline, TORX, square and even up to 50% rounded off fasteners

IDK to me seems like a compromise on the fasteners you use most (in my case either 6 point or reverse Torx) but he swears by them.

 

[neophyte]

Bristol was also referred to as “Spline Drive” or “Bristol Spline”

 

[dnschmidt]

Sorry not really answering your question but a while back a good friend who is a professional mechanic recommended a MATCO set of extra long flex end ratcheting wrenches. The ten-piece set (10-19mm) currently is priced at $625. He said it was hands down best set of wrenches he ever used and he has a very extensive collection. The set is spline drive both on the ratcheting flex end and fixed box end. I questioned him on why I would want a spline drive set and he said it works on pretty much everything. MATCO promotes it as:



IDK to me seems like a compromise on the fasteners you use most (in my case either 6 point or reverse Torx) but he swears by them.

Not the same. I think what the OP is talking about is what was called Bristol drive back in the day. The KABO wrenches you're referencing use what we today call spline drive but if you look at the chart he provided these are female fasteners.

 

[cgrutt]

Not the same. I think what the OP is talking about is what was called Bristol drive back in the day. The KABO wrenches you're referencing use what we today call spline drive but if you look at the chart he provided these are female fasteners.

Well Bristol was indicated on image you are referring to but OP specifically indicated the spline drive triple square and double hex were of interest to him.

And he goes on to state along with image of a male "spline" fastener:

Then we come to the "spline drive" in the image. To me, a spline drive has square teeth and is a driver for a spline bolt.



And it could be an inner spline or an outer spline. Is there something with triangular teeth like the image that is also called a spline drive?

So I'm not convinced he is interested in Bristol drive.

Anyway the MATCO wrenches i was referring to do appear to match the fastener in second image. Just mentioning they could be used with other drive types as well.

 

[Jack Ryan]

Spline drive seems like an artifact of the past. I have a set of Xcelite spine drive 99 bits (interchangeable handle) and I've never seen a true spline drive set screw (internal like an Allen) bolt in my life. I bought this set in the 1970's so they might have been popular way back then.

They are not common but I don't think they are dead. It is more of them being used "somewhere else". They are often marketed as military and space "precision" fasteners.

At the moment I am more interested in boxing them with a name.

Jack

PS If the protocol here is to answer everyone in the same message, let me know.

 

[Jack Ryan]

IDK to me seems like a compromise on the fasteners you use most (in my case either 6 point or reverse Torx) but he swears by them.

I think most people who use spline sockets and ring spanners use them as a universal tool. They do fit a lot of fasteners but not always properly. I'm told they will even unscrew a piece of dowel.

I don't have many to experiment with but if the manufacturer says it, it must be true!

Jack

 

[Jack Ryan]

Bristol was also referred to as “Spline Drive” or “Bristol Spline”

Bristol make yet another "spline drive". It is listed at the bottom right of the first image I posted.

Jack

 

[Roert42]

The “spline drive in your first photo looks like a female version of a normal 12pt fastener.

Your second photo looks nothing like the spline drive in the first. I’m not familiar with this style of fastener.

 

[Jack Ryan]

@cgrutt is correct, I am not really interested in the Bristol drive. In fact, I have never seen on other than in pictures.

It might be that the spline drive in the first image I posted is just not drawn very well. I think we are all on the same page when it comes to the tool itself.



The teeth are not actually square but they are spaced apart.



And the catalogue drawing looks even less like a square spline.



But the fastener itself looks much more like a square spline.

The original problem remain though. If I go the a tool shop or a tool manufacturer's WEB site, I can find a "spline drive" but it could be any of triple square (XZN), double hex or a real spline. Most seem to be XZN.

Why so much imprecision?

Jack

 

[Jack Ryan]

The “spline drive in your first photo looks like a female version of a normal 12pt fastener.

Your second photo looks nothing like the spline drive in the first. I’m not familiar with this style of fastener.

But that's the problem - they are all 12 point splines.

The spline fastener is uncommon in most garages but it is the native fastener for the spline socket/ring spanner that most use as a "fits all".

Jack