Flexshaft very hot - again

[scootertrash]

My flexshaft has always been a lot hotter than others describe. Since the first time I used it, in fact. Now it gets so hot it hurts to grab. After a call to support I'm a little ticked off.

Here are the facts:
- Machine is a pup. It has less than 50 hours on it.
- I performed the 25 hour maintenance steps at 24 hours.
- It ONLY gets hot in the MIDDLE, where it bends
- The spindle and bit are warm but not anywhere near what I'd call hot
- Nothing is loose. X, Y, Z are all tight.
- The bit is not loose
- The bit is brand new
- The flexshaft does not have any wires protruding from the ends, in not kinked, i can't see anything wrong with it
- The spring inside the shaft casing looks fine, nothing unusual
- I've re-seated the flexshaft more than once to see if that's the problem. I'm making sure it engages in the motor end and spindle end.
- I lubed it with the penetrating lube CW currently sells online. I followed the instructions in the video to.The.Letter.
- I also followed the trobleshooting steps here, which recommends a totally different lube but I suppose that's outdated: http://www.carvewright.com/support-p...otor_flexshaft

What's strange is after I lubed it I ran three identical carves - same bit (brand spankin new, first time in machine), same pattern, same wood (poplar). The first carve was hot, the second was what everyone else would say is normal - warm, not hot - and the third was hot again. Hotter, in fact.

I'm fairly upset about the call to support. First question "did you lube it?" Yes. Then I was asked "Well, what do you want to do about it?" I want it to not run hot. Contrary to everything I've read here on the forums the temp mine is running at is a problem however support said "As long as it's not melting the casing it's not too much of a concern." Also, there was no troubleshooting at all. Just "did you lube it?" and then 'You can order another cable if you'd like." No questions about proper seating or wire from it sticking out, etc.

It's not covered under warranty even though it's waaaay below replacement time per the maintenance schedule. I'm pretty well ticked off that the only option is to spend $87.00 on a new flexshaft

Any suggestions? Is there a way to clean the shaft with solvent or something?

I'll probably end up ordering another shaft anyhow because I think there has been something wrong with this one from day one.

[bergerud]

The thing to check is if the flex core is being pushed by compression against the casing in the bend. The core should be "floating" in the sheath. I think this is one of the main causes of heat. My cores protrude about 1/2" out of the truck end of the sheath. Make sure it pulls in and out of the motor end and leaves the 1/2" at the truck end when back in the motor, and that, the core slides easily in and out of the top of the spindle.

[lynnfrwd]

The flexshaft should not need to be lubricated when you get it. In fact, you should rarely need to lubricate it. A new machine will run hot for the first 10 or so hours of use until the spindle gets worked in. I am not sure why yours is particularly hot with 42 hours. I can't imagine that it would need lubricating so soon.

Your list sounds like you know what to look for. I would add to make sure the curvature of the shaft is smooth and not a sharp curve. Also, checking spring for a crimp or a burr on ends of core.

I listened to your conversation with the tech and counseled them on troubleshooting of the flexshaft.

Remember, when you get your new one, it will already have been lubricated.

lynn

[FWMiller]

My flex shaft barely gets warm to the touch. I've got on old A machine with 160 or more hours and I've lubed it once at about 100 hours just because the machine sat for a long time without being used. If yours gets this hot after only 42 hours won't the warranty cover replacement? Sounds like a defect to me.

[DocWheeler]

Do you have the spring-wire support attached tightly to the flex-shaft?
If so, that can cause heat buildup.

I think that I may be in a minority (maybe wrong also) but it seems to me
that there are two places generating heat in the flex-cable, the core and "spring".
The thin lube for the core, in my opinion, does not address the wear area on the "spring".
I have not had a problem with a hot-flex since using the moly chain-lube on the core and
a little moly grease (MolyGraph) on the outside of the core (similar to cam-lube).

[scootertrash]

The flexshaft should not need to be lubricated when you get it. In fact, you should rarely need to lubricate it. A new machine will run hot for the first 10 or so hours of use until the spindle gets worked in. I am not sure why yours is particularly hot with 42 hours. I can't imagine that it would need lubricating so soon.

Your list sounds like you know what to look for. I would add to make sure the curvature of the shaft is smooth and not a sharp curve. Also, checking spring for a crimp or a burr on ends of core.

I listened to your conversation with the tech and counseled them on troubleshooting of the flexshaft.

Remember, when you get your new one, it will already have been lubricated.

lynn

I know you're trying to help me, Lynn, and I appreciate it, but when an expert like you says "not sure why yours is particularly hot with 42 hours" it reinforces my feelings that I got a bum spring from the get go and have (already) shelled out another $87 for a new one.

Edit: Bum shaft, not spring.

[Chris77089]

I have had some customers tell me that their flexshafts run so they have taken a fan and have it blowing across the flexshaft to help dissipate the heat. This may help out with your issue.

[scootertrash]

My flex shaft barely gets warm to the touch. I've got on old A machine with 160 or more hours and I've lubed it once at about 100 hours just because the machine sat for a long time without being used. If yours gets this hot after only 42 hours won't the warranty cover replacement? Sounds like a defect to me.

I was told it is not covered by warranty. And it has always run hotter than what anyone else has ever described. Except the people that have melted them, that is.

I think a free machine is in order

/not really

[scootertrash]

Do you have the spring-wire support attached tightly to the flex-shaft?
If so, that can cause heat buildup.

I think that I may be in a minority (maybe wrong also) but it seems to me
that there are two places generating heat in the flex-cable, the core and "spring".
The thin lube for the core, in my opinion, does not address the wear area on the "spring".
I have not had a problem with a hot-flex since using the moly chain-lube on the core and
a little moly grease (MolyGraph) on the outside of the core (similar to cam-lube).

The support wire is attached tightly with two bands but it gets hot between the outer band and the end of the support. Burning hot.

I forgot to mention that in my original post.

[scootertrash]

I have had some customers tell me that their flexshafts run so they have taken a fan and have it blowing across the flexshaft to help dissipate the heat. This may help out with your issue.

If my flexshaft starts to run I'll put a leash on it. Couldn't resist.

I don't think a fan will help very much but since I have some carves that need to be done I'll try anything until the new shaft arrives. I was almost considering grabbing some fish tank tubing and a pump and water cooling the sucker.