Spindle Flexshaft Assembly--here we go again

[GaryW]

:roll: Spindle Flexshaft Assembly
I think my spindle or that little twister center cable is slipping out of the z-truck side. It will carve for a few minutes then it starts to slip. you can watch the bit slow down and almost stop.
what keeps it from slipping out, is there a washer or something that could of slipped out ????? What keeps the motor side in the motor.
Help this thing is about ready to be trashed.

[fwharris]

Gary,

The only thing that keeps the flex shaft in both the cut motor and the spindle is the square ends of the flex shaft and the square hole that it goes into on each end and how far the flex shaft is inserted into the square hole.

Have you taken the top hat off of the spinde to examine the hole to see if it might be rounded out?

Have you had to change out the QC?

[bjbethke]

:roll: Spindle Flexshaft Assembly
I think my spindle or that little twister center cable is slipping out of the z-truck side. It will carve for a few minutes then it starts to slip. you can watch the bit slow down and almost stop.
what keeps it from slipping out, is there a washer or something that could of slipped out ????? What keeps the motor side in the motor.
Help this thing is about ready to be trashed.
There is a "BB" in the top hat, held in with a spring, you may have lost that BB

[Kenm810]

Here you can see the ball bearing that holds the F/S in place,
and with the Top Hat off, you can see how the square may get chewed-up
if the F/S is allowed to slip while spinning.

[fwharris]

BJB & Ken,

OOOPPSS forgot about that!! Thanks. He must be out looking for it right now!!

[rjustice]

Another possibility is the termination at the end of the outer sheath of the flex shaft coming loose. I remember someone reporting that they had to epoxy it back on.. I believe it was on the motor end.

Hope this helps...

Ron

[Digitalwoodshop]

You asked how the motor end was held in place.... The outside of the motor end of the flex pushes in and twists to lock it in and a screw holds it from twisting.

Like RJustice said, sometimes the hose part of the outside flex cable comes unglued from the twist part, pulling away. This makes the Metal Flex Core too short.... This sounds like what it could be....

Gluing the hose part back to the twist part could help. Use CARE at the motor end as the motor end can CRACK as did 2 of my motors.

And to cover all the bases..... That metal clip around the top hat on top of the Z Truck has a BB or ball bearing that interlocks to the flex shaft grove to hold it in place. Make sure it it there.

Good Luck,

AL

[GaryW]

BTY: Thanks for the photo ref.
but I have a new z-truck and the motor is still square , not worn, I think the spinning shaft is walking up the sheth into the motor, which
lets the shaft to come out of the z-truck.
I'll have to look at the BB, my shaft does have a lump in it, I'll put it back together and make sure the bump is below the BB.
Could the winding direction of the shaft against the spring be un-screwing and force the shaft to walk up into the motor, ????
GaryW


PS: I did reglue the cap onto the sheth, and it does twist and lockscrew to the motor end.

[Digitalwoodshop]

Good Job !!!!

With the flex twisted into the motor the Truck end flex center should stick out the end of the outer case about an inch.

The outer sheath has the grove that the BB rides in to hold it inside the top hat.

AL

[Kenm810]

Something like this

[GaryW]

:oops: Da Ha
I don't have that piece on my twister cable, goto look around the bench
unless it's stuch in the Top Hat

Back in a few :mrgreen:

I'm back
it's there, an the BB is there also, anymore thoughts

[fwharris]

Gary,

Just trying to get a little more info:

When you put the flex shaft and spring back into the housing, can you feel it stop in the motor?

How much of the shaft is sticking out of the end of the housing?

Have you tried reversing the shaft when you put it back in to see if the problem repeats?

What kind of sounds does it make when this is happening?

[GaryW]

Gary,

Just trying to get a little more info:

When you put the flex shaft and spring back into the housing, can you feel it stop in the motor?

How much of the shaft is sticking out of the end of the housing?

Have you tried reversing the shaft when you put it back in to see if the problem repeats?

What kind of sounds does it make when this is happening?







it will run fine for a few minutes then starts making a grinding sound, you can see the bit slow or stop for just a split secound or just slow down and stop,
I figure the grinding is the shaft slipping.
I checked the BB, it just holds the covering in the top hat.
I'm not seeing anythink that keeps the shaft from sliding, think it goes into the motor side,
how far up inside the motor should the shaft be able to slide?
everytime I take the top hat off the cable has moved toward the motor.:???:

[bjbethke]

it will run fine for a few minutes then starts making a grinding sound, you can see the bit slow or stop for just a split secound or just slow down and stop,
I figure the grinding is the shaft slipping.
I checked the BB, it just holds the covering in the top hat.
I'm not seeing anythink that keeps the shaft from sliding, think it goes into the motor side,
how far up inside the motor should the shaft be able to slide?
everytime I take the top hat off the cable has moved toward the motor.:???:
Just noticed you made this statement!
(I checked the BB; it just holds the covering in the top hat.)

Are you saying when you remove the Flex Shaft, the covering stays in the top hat?

If it does that is your problem.

[GaryW]

if I remove the spring over the BB the covering will seperate from the Top hat,
BB in, shaft covering locks to the top hat, at all times the spring and twiser cable will move (spin),
I did have to repoxy the cap to the motor side of the Flexcable covering,
Both the motor and z-truck have square holes. no wear showing,
It still slips
:(
I about ready to expoxy the twister shaft to those square holes.

thanks for all your efforts,

[AskBud]

With the Flex disconnected from the Top Hat about 1/2 to 3/4 inch of the inner flex should be able to grasp. Push it in, toward the motor, and you should still have about the same amount in your fingers. Turn it and you should feel resistance. If it goes further back in toward the motor, you may not have the motor end seated properly.

Here is a link to the PDF on the Flex replacement process.
http://www.carvewright.com/images/service/Service_instructions/CarveWright_service_replace_flexshaft_sheath.pdf
AskBud

[wasacop75]

Ok, but i melted the flex cable cover in one spot over the weekend. could not figure out what the machine/cable was vibrating as bad as it was. Found that the cover was melted. took the shaft out, have it soaking in moly and will try to put it together tomorrow. hope that is a cure..

[Digitalwoodshop]

That melted outer Flex can be bad news.... The core could have been dry..... OR the Damping Spring inside the Flex could be kinked.... I kinked my flex and when I started a carve and walked away, the heat got so bad from the metal to metal that the rubber on the flex started to smoke and melt. It set off my Smoke Detector above my machine.

Yes, you can soak the flex... But you are better off to spend the $75.00 to replace the whole assembly. A damaged outer flex and spring and a spinning flex shaft can start a fire on top of your machine....

Remember TOO much lubrication left on the flex shaft can make it's way into the top hat of the Z Truck and sit on top of the spindle bearing. It soaks into the Ceramic High speed Bearing and causes HEAT buildup. So always keep an eye on the oil buildup on the top of the Spindle.

The way I do my lubrication is to simply touch the flex shaft after the first carve at bit change and feel for a warm outer shaft. Once I feel a warm shaft I pull the flex from the top hat and pull the shaft 1/2 way out. I then squirt a dime size glob of Molly Chain Lube into the center of the flex between my fingers. I then slide it back together.... done.... There are many that Vacuum Pack, hang overnight, and many more involved methods. I find the simple dime size squirt between the fingers to work for me...

AL

[wasacop75]

I have the old fashion soak in a zip top bag going now. i will take out and dry off, let hang a day or two and back to work..
thanks for the help.