Kato GS-4 drive gear slippage help needed

[peteski]

0.040" (um, 0.03937" to be exact) is 1mm.  If you can drill through a 1mm steel axle then you are  pretty darn good! Also remember that you'll be drilling through the plastic axle tube first. If you aren't in perfect alignment then you'll miss going through the metal axle.
What size hole you propose to drill through it (as not to weaken it too much)?

[up1950s]

0.040" (um, 0.03937" to be exact) is 1mm.  If you can drill through a 1mm steel axle then you are  pretty darn good! Also remember that you'll be drilling through the plastic axle tube first. If you aren't in perfect alignment then you'll miss going through the metal axle.
What size hole you propose to drill through it (as not to weaken it too much)?

I am not going to drill baby drill . I always can get a new drive wheel assembly for 150.00 bucks or so , comes with a complete set of GS-4 parts for free . I comshawed (sp) this mechanism from my museum roster . I could put a dummy in the museum collection .

[delamaize]

I am not going to drill baby drill . I always can get a new drive wheel assembly for 150.00 bucks or so , comes with a complete set of GS-4 parts for free . I comshawed (sp) this mechanism from my museum roster . I could put a dummy in the museum collection .

I was able to get 2 of them damaged, one was attacked with a soldering iron, the other suffered from "Old-Bachman-itius" like my first one, but the non-geared axel tubes were the culprit. Call Kato directly and see if you can get a whole new driver set. I was missing a light tube, and needed one more axel, and was able to get one from them directly, when it showed out of stock on their parts page.

[havingfuntoo]

just a comment on the 2 part epoxy, 5 min variants have inferior strength to the slower setting varieties.

[mmagliaro]

If it is hardened steel, it will be very difficult, I agree.  It's .040", so I would go with something like
.016.

You are correct, that it would be hard to do. 

I just don't have a good feeling about it holding up without something mechanical, beyond the glue.
I'm just telling you that if it
were mine, I would try to drill a pin through there.  But no point discussing or arguing about this.  Go ahead and see if the epoxy holds.   If it does, then good on ya.

[up1950s]

Update , the epoxy didn't dry hard enough for some unknown reason . I did a 50/50 mix . I rechecked for a crack and found none . I figured I had little to lose so I flattened the axle ends a bit like a canoe paddle , but not that much . To deter cracking the gear hubs I used a section of brass tubing which is Krazy Glued over it . That increase in the diameter of the female axle tube composite would not fit in the chassis slot , which I knew ahead of time . So I had from the inside of the frame halves counter bored the axle slot area almost to the bearing retaining tabs . I did a check with the motor to make sure it worked without the drivers in place . I then removed the geared axle and pressed in one driver with Krazy Glue making sure the axle was true by eye . I let that dry a few hours , that then repeated then other side but checking quarter and gauge over and over . After few hours I rechecked function and checked for torque with my finger on the whirling drivers , left , right , and both , in both directions . There was some slight hiccup in the rotation , nothing that a break in wouldn't cure , So I decided to park the 9V battery and get out the power pack . All was working ok so I spooled it up a bit , about 3/4 throttle , then I thumbed the racing driver a bit to break it in . Well the skinny a$$ universal drive shaft twisted into 2 pieces . I managed to adapt a Kato E-8 drive shaft whose motor hex end was perfect , the shaft length was about the same but I did need to lop off the center pin from the end of the hex end . The shaft diameter is more robust as is ball and pins . I needed to slice the ball and pins to a continuation of the shaft . Note that the E-8 gear tower shaft is bigger in diameter , and the worm on the GS-4 is more TPI than the coarser E-8 worm , so swapping out is a no go . I then drilled through the gear tower female coupling / drive shaft and pinned it with brass wire . I glued it all together as the alignment of the motor/drive shaft / gear tower are exactly aligned or close enough that the motor end free movement will be good enough . I will wait till tomorrow to give it more of my man handling . Trainland sent me a email today and they have Kato GS-4's going for 145.00 , one will be delivered to me tomorrow .  I need to do any transplants the patient wont complain as it is slated for museum display only .

[peteski]

Wow Richie - you really like to *MANHANDLE* your locos!  I don't think Kato GS-4 was designed for this. It is a fragile loco. I also don't understand why you want to make it *THAT* robust. As-is, it will pull plenty of cars and if you do overload it, then it will just spin its drivers on the track (maybe even throw a traction tire). I'm speechless.

[victor miranda]

.... um....
remind me to keep you away from the TnT sticks...

Hi up1950s
the good news is that Kato still has the driveshafts for sale.
and that little motor has a lot of torque. dammm.

you have some thing else wrong with that loco. somewhere.
that shaft should not have failed.
 check that.  it may have failed when the axle was popped
and was not noticed and when the load returned it finished failing.

still that loco seems to have a problem.  the fix holds.
no wobble means it is straight.  good work! 
now find the real reason it failed the first time....

believe me, I want to know.

victor

[up1950s]

I am mid way to a cure of the slip out of quarter lockup hell . I soldered the 3 driver rods on each side together . Now I just have to fine tune it by reaming the holes just a touch bigger , I already increased them from .035 to .042 on drivers 1 , 3, and 4 Works but I think a touch more slop might help . I would much rather take the time to locate the exact driver and side than to ream them all . With this deal the drivers can't slip even if they are loose . I also works better than it ever did before , or as good .

[victor miranda]

I think I am going to hide the lighter as well.

hi up1950s

you have soldered the siderods together?!?
please tell me you are joking.

are you aware the driver centers are removable?
ok they pop loose from the metal part of the driver when I try to pull the crank pin.
sometimes.

is the slip there ?

victor

[superturbine]

Ok...... Ive read Richie's post mutiple times, perhaps he is serious.  Glad you bought another GS-4 for replacement parts!

[victor miranda]

hi superturbine,

I think the new loco is because this one became 'parts'...

I am at a loss for solutions. the things up1950s says he has done are
throughly unbelieveable to me.

he is good at reporting accurately so I believe what he says.
but I can't figure out what went wrong.

victor

[up1950s]

I think I am going to hide the lighter as well.

hi up1950s

you have soldered the siderods together?!?
please tell me you are joking.

are you aware the driver centers are removable?
ok they pop loose from the metal part of the driver when I try to pull the crank pin.
sometimes.

is the slip there ?

victor

Yeah , I found the plastic outer centers are pop outable because one flipped its lid all by its self . They have a back side molded on pin which keeps them aligned with the with the see-through metal backing . They are not the problem , the problem is there isn't enough friction on the outside of a 1MM shaft that only sticks in a hole about 3/16 of an inch or so . Same holds true with the coupling at the gear tower . They either needed a larger diameter shaft which would have more SNAPI ( square gnats asses per inch ) for a grippier fit , and or a robust mechanical torque lock which would automatically create and maintain quarter . The soldering of the 3 driver rods end to end on each side stops any out of quartering from happening . The end result is it looks the same and is more reliable on a design that is prone to quartering problems . Sometimes dumbing down to old school methods is the way to go . Adding individual driver rods is a nice touch on Kato's part but that apparently requires a quarter fail proof design . You no doubt could fix this the proper way , to Kato specs or better , but I am stuck with this dope under my hat  . He's family , and I don't want him to feel too useless as not to try something , be it a fools endeavor or a interesting fix worth remembering .    

[SkipGear]

Knock on wood but my GS-4 just did another 5 hour tour last weekend on the Ntrak layout pulling the full 18 car Daylight without a hitch. Mine was from the original release which for some reason didn't seem to have these issues. It seems like the cracked axle problems arrived with the second batch.

[victor miranda]

  fear not!  I live with a dope under my hat also.

you are doing as good as any of us.

my first fix recomendation for this issue is new Kato parts.
For a lot of the reasons you are encountering.
this is not an easy fix. in addition to making a brass collar and milling the frame
there is the quartering job which has little room for error.

I really like the "square gnats asses per inch" measurement.
'cause kato sure uses a lot to get that job done.

and if even one of them lets go.... its gnat asses everywhere!


call Kato on Monday and plead for a set of drivers
and get a new set of side rods.

point them to this thread and let them know you tried to fix it first.
maybe they will have mercy on you.

victor