I have made my own 203/205 doubler and my concern is this. My 203 output shaft has been resplined for the input of my 205. This portion of the shaft is only about 24HrC hardness as it is. I tried drawing a piece of the shaft back to see how soft it would get and it went back to about 18HrC. I have heard of these splines getting stipped occasionally because of the torque load and was wondering...

What hardness should output splines be to insure adequate strength?

I oil quenced a piece of the shaft tonight and tomorrow I should know how hard it is. Should I only case harden it with like "kasenite"? Anyone have a clue what I am talking about or am I just talking out my ....

Todd

Carroll Smith recommends a heat treat to HRC 52-56 for halfshafts. :grainofsalt:

That is pretty hard! I was guessing mid to upper 40's. I would say that I am way under at 24.

Did you anneal the shaft before it was cut? If you did then it shoud be re-hardened. If you didn't anneal it then it should be harder than that on C scale I would think. What type of hardness tester did you use? I am using a shaft from Wagoner Machine Shop, that was not annealed before re-splining from . I questioned them about this and they said that the "Govt. Muel" has been running the same shaft for three years and has not had any problems. If the shaft hasn't been annealed, you can cut it with carbide tools. It all depends on what you want. I you want to cut it with a gear cutter to get the right pressure angles, you might have a hard time finding one made from carbide. If you use an endmill you can cut very hard material but the pressure angle will be off alittle. The pressure angle is not that big of a deal unless you are looking for Ultimate Strength. Most shafts that are in used trannys and t-cases have worn that all down anyway. Even Currie used the endmill method to re-spline their axles. If they do it than its good enough for me. I beleive that is why WMS used endmills to cut their splines and doesn't bother with the heat treat. The shaft will still be pretty hard even at the reduced diameter.

Case hardening is a good thing. It will give you a hard surface to increase wear resistance and maintain the softer core that provides ductility and resistance to fracture. Im just not sure that it is necessary for you application. What is your Application? It this a vehicle that is going to be used for extreem competition. If it is, then I would consider heat treating the shafts. If not, I wouldn't worry about it. I also agree that 52-56 RC is about ideal, any harder they would probably just crack.

Todd,

Have you come up with any more information on this? This is a project I want to do in the future, and I'm curious to hear what you have found out.

Ben

I have tried several things (heat treating) with some of the excess material that the saft is made of..

Material harndess as is - 24 hrc
Oil quenched - 38hrc
Water quenced - 41hrc
Air quenced - 59hrc

I think that what I am going to do is to use some kasenite material on the shafts and quench it in water. That should give the splines a outside case hardness of around 62-68hrc and leave the inside core around 41hrc. I am afraid that 59hrc from air cooling would be too much for a through hardness.

Any thoughts

Todd

How hot do you heat it before you quench? Are you using an oven or a torch? I did a search for kasenite on the web, found a little info, but couldn't find out where to buy it. Where do you buy yours?

you can pick up kasenite from brownells gunsmithing supplys, do a search on the web for the place, i know they have it. mike

I get my kasenite from work (at a very reduced price I might add!!)

I used a oven for the air hardening and the water quench and a torch for the others. I am going to use the torch and water quench for my kasenite test. I should have a good idea of the hardness both core and case by the first of the week. I heat it pretty hot with the torch but not too hot or you could begin distorting it. When I get ready to harden the actual shaft I am going to rig it up in my drill press and let it turn it while I heat. I hope that will prevent it from unevenly heating and also distorting any from gravity if it was laying on its side (which I doubt anyways). I do not want to effect the portion of the shaft that was not cut on and is still factory condition so a oven is out of the question.

Alaska Offroad: We have a hardness tester at work and I use the diamond tip for the C scale of hardness I do not know the brand though. The shaft was sent to Moser and I doubt that they anealed it before they cut it since any case would have been turned off in the lathe, but I don't know for sure.

Where can you get an end mill small enough to do axle splining?

Does Currie do theirs on a CNC? Seems like that would be very hard to do on a mill.

I am just learning how to run a Mill.

Thanks,
Sean

You can use any diameter endmill to cut splines with, but most are probably using .500" carbide endmills. Here is a .dwg file that shows how this is done.

http://www.alaskaoffroad.com/images/Tech/ENDMILLSPLINING.DWG

The circle represents a 1.5" dia shaft and the open ended rectangle represents the endmill.

If you email me with your spline count and shaft diameter I can draw it up for you with exact dimensions.

bgreen@alaskaoffroad.com

:usa:

Originally posted by Station
Where can you get an end mill small enough to do axle splining?

Does Currie do theirs on a CNC? Seems like that would be very hard to do on a mill.

I am just learning how to run a Mill.

Thanks,
Sean

You use a dividing head on a regular mill. It is not that hard to do. Takes about one hour or less to do 35 splines. You can use 1/2" end mill and go right up to the shoulder of the shaft. So the root of the spline will be about 1/4" away from that shoulder. That is how most people are building the 203 shafts.

If I had to guess I would say that moser cut mine with a hobb. If not the cutter had to be at least 2" in diameter considering where they cut into the base of the bearing diameter.

I cut splines for my T19/205 adapter using a dividing head and it worked well. I did not use a endmill but a side cutter. Worked pretty well but broke two inserts.

Todd

Thats good. They should be done that way (with the proper cutter). I think that it is a toss-up though, on these type of shafts. you trade correct pressure angle for length of spline. I don't really know what is better.

I should have my truck running by spring, (its using endmil splines) the proof is in the pudding. I hope that endmill splines are as strong as they say they are.

BMSN123,
How long did you put the shaft in the oven for, and at what temp? When I built the shaft for my 231 planetary crawler I used a stock 231 mainshaft that was cut and resplined. We turned it down and used a side cutter, and a dividing head in the mill. I tested it, and after cutting the splines the hardness was 32C. We hardened the splines with a torch and water, and ended up with 56C. The original factory splines were 61C.
We put the shaft in a welding lathe, turning slow, and heated it with the biggest rosebud we could find, hooked to the biggest acetylen tank in the shop. We had three guys, one with the torch, one on the on/off pedal ready to open the chuck, and one ready with the gloves and tongs. We dunked it in a gallon coffee can with room temp water, and the water boiled almost instantly. I would recomend a 5 gallon bucket with a little colder water. This would get it just a little harder. We heated it with the torch just before the splines looked like they were ready to start running (melting). I think it worked alright.
Good luck (It is very never racking while you are doing it),
Brian

Very interesting and informative posts...keep em comming. How are internal splines cut? Could you internally spline the input gear with with non involute splines at the same pressure angle as the 203 shaft?

On spline length, how much spline, lenght wise is sufficient for a 35 spline shaft? IIRC, my Warn 35 spline hubs have about 1" of spline. I have a D60 spool, which has 1 3/8" of spline. Can you get by with with less than 1"? How about 3/4"?

Internal Splines are mostly broached. I think Moser can do this for you. I don't think you would want to only have 3/4" of spline. Every splined shaft I have seen has had an extra 1/2" to 3/4". You need to have room for the relief of the cutter too (A round cutter won't cut the full depth at the end of the spline).
Hope this helps

I guess it is a little OT but, with all the posts on "how" to make splines, maybe not. So, what about using EDM for splining, male or female.

Im thinking more along the lines of re-splining a input gear, and a drive flange. Do larger diameter splines need more length than small ones? What about course splines, more or less?

Im thinking of doin a 203-d300 doubler, and would like to go with 32 splines, to simplify my Ford 205 swap down the line.

I don't think EDM is cost-effective at least here in Denver it is not. I got a price on EDMing a 3/8" key way in a gear that is 58Rc and it was going to cost me $125. That was one key and not 35 splines.

Originally posted by Alaska Offroad
You can use any diameter endmill to cut splines with, but most are probably using .500" carbide endmills. Here is a .dwg file that shows how this is done.

http://www.alaskaoffroad.com/images/Tech/ENDMILLSPLINING.DWG

The circle represents a 1.5" dia shaft and the open ended rectangle represents the endmill.

If you email me with your spline count and shaft diameter I can draw it up for you with exact dimensions.

bgreen@alaskaoffroad.com

:usa:

Thanks allot. I might have to take you up on that offer as soon as I know exactly what I need. My new home shop has a mill and lathe in it which I am learning to use.
I am apprenticing at a high end ,materials process, machine shop where we build high dollar machines for large companys(we just designed and built a machine that installs crankshaft counterbalancers for Detroit deisel). We also make dies, and molds(lunchbox molds , knife holders, molds for law enforecement gun handles etc). I am learning allot very quickly.

I have one more question simular to a question already asked above. Can you use an endmill to do internal splines? I was under the impression that the ONLY way that it can be done is with a broach. The problem is that nobody(in this country anyway) already makes the broach that I need. It would have to be custom made =$$$.

Thanks,
Sean

Originally posted by JEEPRZ
Im thinking more along the lines of re-splining a input gear, and a drive flange. Do larger diameter splines need more length than small ones? What about course splines, more or less?

Im thinking of doin a 203-d300 doubler, and would like to go with 32 splines, to simplify my Ford 205 swap down the line.

Um ford 205's are 31 spline input.... just FYI....

your right...i had output shafts on my mind....

Sorry, they have got to be broached. :(


I have one more question simular to a question already asked above. Can you use an endmill to do internal splines? I was under the impression that the ONLY way that it can be done is with a broach. The problem is that nobody(in this country anyway) already makes the broach that I need. It would have to be custom made =$$$.

Originally posted by Station


Thanks allot. I might have to take you up on that offer as soon as I know exactly what I need. My new home shop has a mill and lathe in it which I am learning to use.
I am apprenticing at a high end ,materials process, machine shop where we build high dollar machines for large companys(we just designed and built a machine that installs crankshaft counterbalancers for Detroit deisel). We also make dies, and molds(lunchbox molds , knife holders, molds for law enforecement gun handles etc). I am learning allot very quickly.

I have one more question simular to a question already asked above. Can you use an endmill to do internal splines? I was under the impression that the ONLY way that it can be done is with a broach. The problem is that nobody(in this country anyway) already makes the broach that I need. It would have to be custom made =$$$.

Thanks,
Sean

They don't have to be broached they can be shaped on a gear shaper. That will be your best bet and the cheapest way for you to go.

oh ya. Good idea. I guess he could make an electrode for an EDM. Or have it cut with a wire EDM.

How well does a gear shaper do with hardened material? Who can do this for a resonable price? I have found that if you can buy something, its usually cheaper than paying someone to custom make it. Especially for machine work. :eek:

Oh yeah, I forgot the option of wire cutting. I knew that.
Our machine shop has 2 wire EDM's, but the cost(even at my discount) is too much for me.


Sean