Mini spool.

[smoked240]

Alright well at first I was going to make a full spool for my R200 diff, but after thinking it over, I might be better off making a Mini spool to take place of my Viscious. I'm kinda asking to anyone who might have tried this or thought it over. I figured it would be easier to make if it was the same exact size as the Viscious, but splines through it to lock both axles in. I know a few on here have tackled making a spool but what are your thought on a mini spool? I'll be modeling it on solid works or I'll just do it on edge cam to give you guys a better idea.

[smoked240]

This is what I was going to start with as a spool.

Keep in mind that the dimensions are no where near right as of this moment since I haven't removed the carrier.

http://i30.photobucket.com/albums/c349/SmallMischief/Spool6.png

Then I altered it for a more practical one. Keep in mind that on this side, there would be a stop for the bearing but I need to renew my license soon so I can pull up the right one.

http://i30.photobucket.com/albums/c349/SmallMischief/Spool7-1.png

I still want to machine the spool, but our EDM machine won't go high enough to make the splines. We could remove the plate in it to accept it but it is a pan to do.

I can't remember who but I was speaking with someone about which material to use. Anyone have any idea's which would work? I was told that 6065 T-56(can't remember if it was T-56 or something else) would be perfect to use. I just have to find a strong aluminum that will hold up.

Next week I should have something mocked up for the mini-spool that will fit inside the original carrier.

[smoked240]

If no one has taken apart the VLSD, here is the inside.
http://i30.photobucket.com/albums/c349/SmallMischief/phone027.jpg
This is the Viscious it's self.
http://i30.photobucket.com/albums/c349/SmallMischief/phone028.jpg
Spider gears
http://i30.photobucket.com/albums/c349/SmallMischief/phone029.jpg
http://i30.photobucket.com/albums/c349/SmallMischief/phone030.jpg

Bottom gear to connect it. Notice the slots in the carrier,that's what connects the ring gear to the axle shafts.
http://i30.photobucket.com/albums/c349/SmallMischief/phone031.jpg
http://i30.photobucket.com/albums/c349/SmallMischief/phone032.jpg
This is what the mini spool is going to look like. I just started machining it today, so I hope to have it done by spring break so I can try it out. I will be using a mild steel. If It doesn't work out I will machine it out of 4140 steel.

http://i30.photobucket.com/albums/c349/SmallMischief/240SXSPOOL.jpg

[feadz]

Do you have any experience with FEA(finite element analysis)? You could load your model into Algor and see what kind of stresses your spool would experience due to the forces acting on it. Once you have it loaded, it's easy to change the material inside the program to find out the max stresses and see if it's safe.

[smoked240]

Do you have any experience with FEA(finite element analysis)? You could load your model into Algor and see what kind of stresses your spool would experience due to the forces acting on it. Once you have it loaded, it's easy to change the material inside the program to find out the max stresses and see if it's safe.


I do not have that program, but solidworks has something like it I just haven't learned it yet. I know 4140 won't have a problem with breaking. I just want to try something cheaper.

[Bluejayde]

Not a single "Just weld it!" post? What forum did I wander into?

[smoked240]

Not a single "Just weld it!" post? What forum did I wander into?

Haha no shit. I am surprised. I wouldn't want to weld these gears.

[UNITEDMASTER]

OK here you go just weld it !!! Why not mini spool = same thing as far as I know. Solid lock at all times,yea???

[smoked240]

OK here you go just weld it !!! Why not mini spool = same thing as far as I know. Solid lock at all times,yea???


If i'm not mistaken how the VLSD works, if you were to weld the spider gears it would still slip on one side. On the 2nd picture the Viscious, one side turns and the other also.

Plus if I get sick of the mini spool down the road I can just switch it out.

[UNITEDMASTER]

Ok OK. Im just not sure what your trying to acheive. Im a lil old skool ,If your looking for solid lock get a open diff/STD and weld it. Or just buy a nice diff break it in,then tune the lock up to your liking. DONE???

[smoked240]

Ok OK. Im just not sure what your trying to acheive. Im a lil old skool ,If your looking for solid lock get a open diff/STD and weld it. Or just buy a nice diff break it in,then tune the lock up to your liking. DONE???

If you are old skool you would know of spools. Which is one solid chunk of steel(some are even aluminum) that the ring gear bolts to and the axle shafts slide into it. It does the exact same thing as welding the spider gears but doesn't ruin gears and or carrier. Now a mini spool is basically the same thing but all it does is replace the spider gears. you can buy/make them and it does the same thing as welding but are cheap and doesn't ruin anything.

I can't really afford to buy a 2 way while going to school, so this should work just fine, as long as the metal holds up.

[omgRWDgoodness!]

Not really sure what a "viscious" (vicious?) diff is, but it sure doesn't sound like something I'd want on my car...

Now, a VISCOUS diff sounds much more appealing!

http://i56.tinypic.com/6hq820.jpg

:D <3

[smoked240]

Thanks for the correction haha. but I am still going to spell it like that.

[UNITEDMASTER]

If you are old skool you would know of spools. Which is one solid chunk of steel(some are even aluminum) that the ring gear bolts to and the axle shafts slide into it. It does the exact same thing as welding the spider gears but doesn't ruin gears and or carrier. Now a mini spool is basically the same thing but all it does is replace the spider gears. you can buy/make them and it does the same thing as welding but are cheap and doesn't ruin anything.

I can't really afford to buy a 2 way while going to school, so this should work just fine, as long as the metal holds up.


Based on that I would suggest you just buy another pumpkin & weld that,then swap them.How much do you estimate it will cost you in time & effort to R&d a mini spool for no real valid reason . Just Sayin:D Yea I know how a spool works/what it does

Dont over complicate things its only a 240:D

[Pure_JDM]

I'd weld an open... I can appreciate your time, research, as well as design, but in all reality it isn't worth the effort on a 240 unless you're planning on mass-producing them (which it doesn't sound like you are).

Using your own logic about your possible steel failure, if your mild steel doesn't hold up, and breaks, you will in essence ruin a rear-end. Same as "welding one" according to you, except my welded ones haven't failed, nor ruined anything except tires...

[smoked240]

I'd weld an open... I can appreciate your time, research, as well as design, but in all reality it isn't worth the effort on a 240 unless you're planning on mass-producing them (which it doesn't sound like you are).

Using your own logic about your possible steel failure, if your mild steel doesn't hold up, and breaks, you will in essence ruin a rear-end. Same as "welding one" according to you, except my welded ones haven't failed, nor ruined anything except tires...


Producing them is a possibility. I would produce a full spool,not this one. This mini is just to see if it can be done.

All I will ruin is the spool itself. If that were to happen all I will need to do is pull the diff and put my vicous back in and be done. The dowl pins won't break. The only weak point in using this steel would be the splines, and even there they still might not be a problem. I could heat treat the steel I will be using, but then it would be more prone to exploding and destroying my gears. If I leave it in this state, being at around 8 rockwell, it will just snap at a weak point. The only place any force is being applied fully is the dowl pins and splines. There is a chance this will break, and if it does I will just use 4140 and not worry about it.

I haven't had to put a lot of R&D into it. It took me 20 minutes to think of how I wanted it to turn out, about an hour to model it up and I just started machining it now, which will only take a few hours.

See I know 4140 steel will work flawlessly. I am just going to attempt it with a cheaper steel, since 4140 get's pretty expensive.

[smoked240]

Based on that I would suggest you just buy another pumpkin & weld that,then swap them.How much do you estimate it will cost you in time & effort to R&d a mini spool for no real valid reason . Just Sayin:D Yea I know how a spool works/what it does

Dont over complicate things its only a 240:D

It would cost me more to buy an open diff and weld it compared to this.

I am going to school for machining, in reality this is just helping my ability's even more.

I'm not really making it complicated, or trying anyways. I just wanted to try and make this since not many people have made a spool for a 240. I have seen some, but very few.

If I do it with this steel and it works just fine then great. If not I will have to just use a different steel. If I can make it using cheaper steel and it holds up just fine, then I will plan to produce them or ones like it in the near future. A friend who went to school for machining wants to open a shop with me. But it won't be for atleast 2-3 years since I am going to school for robotics engineer also.

[Pure_JDM]

Sounds good... seems like you're pretty set on it, so I admire the determination. Good luck, and update us once it's installed and tested.

[smoked240]

Sounds good... seems like you're pretty set on it, so I admire the determination. Good luck, and update us once it's installed and tested.

Will do! Hell if this even turns out maybe some people with the VLSD would be interested. I plan to have it completed for spring break so I can get it in the car when I get home.

[codyace]

You've seemingly forgot that 85% of 240 owners are need a freakin 'how to' or a guide for simple bolt on stuff. WHile I think what you are doing is neat (and it will obviously work), I just think weveryone is looking past the difficulty for the massses...most of them couldn't even figure out how to tear their differential apart in the first place, so they simply get them welded as you can do it in car.


I don't want to sound like a Debby Downer, just trying to put some things in your mind before you dump of ton of time into making these, and only finding 3 people to buy them at your price point...gotta think, unless it's less than 100 bucks, nobody wants them as you can get a welded one for 50-75 bucks most of the time.


Just food for thought. Keep tearing into it though, nice seeing someone doing something different than putting a 225 on a 10" wide wheel.

[smoked240]

You've seemingly forgot that 85% of 240 owners are need a freakin 'how to' or a guide for simple bolt on stuff. WHile I think what you are doing is neat (and it will obviously work), I just think weveryone is looking past the difficulty for the massses...most of them couldn't even figure out how to tear their differential apart in the first place, so they simply get them welded as you can do it in car.


I don't want to sound like a Debby Downer, just trying to put some things in your mind before you dump of ton of time into making these, and only finding 3 people to buy them at your price point...gotta think, unless it's less than 100 bucks, nobody wants them as you can get a welded one for 50-75 bucks most of the time.


Just food for thought. Keep tearing into it though, nice seeing someone doing something different than putting a 225 on a 10" wide wheel.

Thanks man! I know what you mean. I would love to mass produce them but your right when you say over half needs a how to on bolt on shit. I'm thinking more along the lines if someone who knows what they want and knows of them I would gladly make them one.

[codyace]

That's really the way to fly. I know with my AC brackets and Alternator brackets, it's nice to be able to have them made in small batches or on 'need' basis instead of making a whol ebunch and sitting on them for years.

[RedSiBaron]

glad someone is thinking about this...ive been wondering if anyone made one, i havnt been able to find one anywhere at all...no one makes one right?

[smoked240]

That's really the way to fly. I know with my AC brackets and Alternator brackets, it's nice to be able to have them made in small batches or on 'need' basis instead of making a whol ebunch and sitting on them for years.

Haha yeah.

glad someone is thinking about this...ive been wondering if anyone made one, i havnt been able to find one anywhere at all...no one makes one right?

No company makes a mini spool/spool for the 240sx. I have seen a couple guys do it but little talk of producing them.

I could model up a spool to fit into the open carriers also. I haven't seen the 240sx one up close but it should be just like a normal open carrier. The 4 spider gears and there is a large pin going through the carrier and 2 spider gears to lock them together. That one would be a lot easier to do compared to this one.

[superJoy]

I'd be careful; you don't seem to be doing any stress analysis for this thing.

If you crunch the numbers, you might end up with a design that's safer, lighter, cheaper, etc.

It's a cool thing to do in your spare time though. Keep it up.

You mentioned engineering school? If you aren't attending already, seriously consider it. It's not very hands-on, compared to technical school, but it will open your mind up in a big way. Sometimes painfully, haha.

[smoked240]

I'd be careful; you don't seem to be doing any stress analysis for this thing.

If you crunch the numbers, you might end up with a design that's safer, lighter, cheaper, etc.

It's a cool thing to do in your spare time though. Keep it up.

You mentioned engineering school? If you aren't attending already, seriously consider it. It's not very hands-on, compared to technical school, but it will open your mind up in a big way. Sometimes painfully, haha.


I can do it on solid works I just am not 100% sure on how to.

I looked over the design about 3 times and each time it slightly changed into this. My first design was to machine it all in one piece, but then would leave a huge stress point on the 4 posts. So I came down to drilling blind holes and pressing in dowl pins, since dowl pins are very strong and hard to break. Especially at 3/4 pins.

I would love to go through engineering school but I am a more hands on guy. That's why I decided to go to this intense machine program. If you go to a 2 year school for it, the first year is all bullshit bookwork. I still learn all of the stuff but It's being taught hands on. Learn it by doing it, not reading about it. The very first day of class we were already machining. I know a couple colleges that won't let you touch a mill/lathe until 2nd year.

[feadz]

I can throw it into Algor and give you some rough estimates on the stresses and where the stress risers are going to be if you have a model with the exact dimensions that you're going to use. We would just have to estimate what kind of forces are acting on it and where at. Looks like its just going to be a lot of shear stress due to torque and not a significant amount of bending stress, but i'm not really sure on the mechanics of this spool. I've only studied stress and strain analysis for static loading, but I can talk to some of my professors and see how to go about for dynamic loading cases. I'm actually in need of a project for my machine design course.

[smoked240]

I can throw it into Algor and give you some rough estimates on the stresses and where the stress risers are going to be if you have a model with the exact dimensions that you're going to use. We would just have to estimate what kind of forces are acting on it and where at. Looks like its just going to be a lot of shear stress due to torque and not a significant amount of bending stress, but i'm not really sure on the mechanics of this spool. I've only studied stress and strain analysis for static loading, but I can talk to some of my professors and see how to go about for dynamic loading cases. I'm actually in need of a project for my machine design course.


Sorry for the delay. That would be sweet. I will have to alter the model some since the 4 pins arn't exactly center, there closer to one edge.

I have it all machined to size and have 2 holes finished.
I just need to cut the pins down to size and grind flats on them.

http://i30.photobucket.com/albums/c349/SmallMischief/IMAG0055.jpg

[smoked240]

update. I got the pins grinded down and put flats on it. It goes together with a little bit of wiggling, just how I wanted it.

Next are the splines. I need to make my own endmill to cut the splines into the carbon. Oh and I have one week to do it.

http://i30.photobucket.com/albums/c349/SmallMischief/IMAG0056.jpg

http://i30.photobucket.com/albums/c349/SmallMischief/IMAG0057.jpg

http://i30.photobucket.com/albums/c349/SmallMischief/IMAG0058.jpg

Oh yeah. and fuck snap rings.

Bullshit.
http://i30.photobucket.com/albums/c349/SmallMischief/IMAG0053.jpg
http://i30.photobucket.com/albums/c349/SmallMischief/IMAG0054.jpg

[smoked240]

Friday I grinded up some Carbon blanks and a endmill so I can start on the splines. It was such a bitch to take 3 2"x2" square carbon and surface grind it to 1.175 round. I swear my arm was about to fall off. took close to 2 hours.

[WeirPerformance]

glad someone is thinking about this...ive been wondering if anyone made one, i havnt been able to find one anywhere at all...no one makes one right?

We have full spools for the R200 on the shelf. They fit the open diff axles VLSD axles will not work.
Weir Performance - Spools & Limited Slip Units (http://www.weirperformance.com/spoolslimitedslipunits.html)

Not trying to thread jack, just trying to get the word out that the spool is available.

[duffman1278]

I do not have that program, but solidworks has something like it I just haven't learned it yet. I know 4140 won't have a problem with breaking. I just want to try something cheaper.

COSMO's is decent for static FEA and some buckling and at times fatigue (if you have the appropriate data) but it's not all that great. Wouldn't suggest using ALGOR, ANSYS, NASTRAN, and etc unless you know what you're doing. It's not like drawing parts on solidworks where you can just wing it or learn from online tutorials.

Nice project so far, keep us updated.

[smoked240]

after trying to get it together I came to the conclusion I had to harden the splines since the snap rings were just digging into it. So I used some Hardening compound to just harden the splines and I will be trying it out in a couple of weeks.