[l u k e]

Ran some coolant through the milling today getting ready to actually cut something and found these leaks. Anyone have any ideas what it may be before I tear the covers off?



It ran steady like that for 20 minutes until I shut it down.

[DaOne]

On mine there are 2 covers (one on each side) that are glued on with a sealant. This Is supposed to help cool the spindle cartridge. Mine leaked just as yours is doing. They had to be taken off, cleaned and re-glued in place. The sealant used was a special one and I cant remember what it was.

[l u k e]

Seems like an odd way to go about containing the coolant...

[wms]

This can happen if you "Deadhead" the coolant..it blows out the sealant on the cover plates..

[l u k e]

Whats deadhead?

Turning on the coolant with the spigots closed?

Is there a special sealant I need to fix it?

[DaOne]

Yep... turning off all the coolant nozzles is a big no no.

[l u k e]

learning the hard way...

[Geof]

Frequently I have had all the coolant nozzles turned off and had the pump running without any harm. This is on a variety of machines all equipped with the high volume pumps. These are centrifugal pumps and they can only develop about 25 psi which is not much pressure.

Some of my machines have suffered burst coolant lines in the head. The plastic tube fatigues where it flexes as the head goes up and down and can eventually crack. This does cause something of a mess when the machine is running unattended and 80 gallons of coolant get pumped onto the floor and the tool breaks through lack of coolant.

[haastec]

Haas uses a product called Sikaflex, or used to anyways. The plates are held in place wish screws so all you really need is a good quality qasket maker silicone. I have had good luck using the Loctite brand ultra black.

Use the coolant override in settings to turn on/off coolant instead of the valves.

[l u k e]

The plates are held in place wish screws

Is it really the surrounding exterior cover on the spindle that contains the coolant or is there a tank of sorts under it?

[haastec]

There is a coolant jacket that is part of the casting which houses and surrounds the spindle and helps to dissipate any excess heat. All this is under the exterior sheetmetal covers.

Pull the covers off the head and it will be quite clear what plates we are talking about that need to be resealed.

[l u k e]

OK cool. I was looking at the size of the cover and was thinking it would be a B!$^% to line up with a bead of silicone around the edge and secure it in place with a good seal.

[Machineit]

If you decide to use silicone on the housing plates, make sure to give it a full 24 hour cure time. There are not enough screws spaced around the plates and if you turn it on too soon it can blow it again. The plates actually warp or are pushed out and this is especially true if it has a little higher rated after market pump. Lot of square inches on the plates. Had one at work that way.

Also a great time to clean and lube any areas that need attention under there. Remember to remove the wire from the tool release button before you just lift it off, that will prevent damage to the switch. Also make a note to reattach that same wire. Don't want to have to remove the housing again just to hook up that wire.

Have fun!

Mike

P.S.: Might need your nose plugs if those plates have not been off before and of course clean it while you are in there. And to drain first I think you can open the little line-lock coolant spout, don't think the adjustable draws off of the bottom so will not drain.

[l u k e]

Thanks for the tips Mike.

Two questions, about how long (not including dry time) does it typically take to do this job?


Also, how difficult is it to do with the SMTC?

It looks like some of the screws will be hard to get at, although I haven't ran the spindle up and down to see how accessible they are on that side.

[Matt@RFR]

Also, how difficult is it to do with the SMTC?

It looks like some of the screws will be hard to get at, although I haven't ran the spindle up and down to see how accessible they are on that side.

That's exactly what you have to do. Get the ones you can get to, then move the Z and get the rest. Shouldn't take more than 20 minutes to take that cover off.

[l u k e]

Haas uses a product called Sikaflex, or used to anyways.

I found this stuff online; cost is about the same silicone. They offer white, grey and black. I couldn't fine any difference in the three except color; I assume performance wise they are all the same. (??)

[hercules]

When my machine came new I got anxious waiting for the install tech (took 3 weeks to get someone here) so I started fiddling around and sealed up some of the seams with silicone. I didn't finish though so when the HFO install technician finally came he did all the rest of the seams using Sikaflex. 3 years later and the seams that had silicone had to be resealed, the ones with Sikaflex are still holding good. Just one guy's experience and not real scientific, but it appears to me the Sikaflex does better when exposed to coolant.

[l u k e]

Yea I'm going to use Sikaflex, found it online. It's not very expensive.

[Ydna]

We've had the same leak occur a few years ago. Except it wasn't caused by the tool's coolant nozzles, but rather the coolant washdown hose. Somebody turned the pump on and walked away for a bathroom break before actually washing the machine. A slight leak developed.
Your machine might not have the washdown hose but you can easily add one if you wish.

[tpractice]

If i'm not mistaken, is this the same machine you posted pictures of a while back with the missing plug in the bottom of the spindle head? Before pulling any plates off, remove the sheetmetal side head cover opposite the toolchanger and turn on the coolant. If you look towards the rear of the spindle head you will see a tube that runs from the bottom of the spindle head to the top. Check the tube connections for leaks. Also. some of the plates had a pipe plug installed that is removed when using a chiller, make sure it isn't leaking. As far as I know, the coolant side plate that is bolted to spindle head only uses a gasket and no sealant. Sikaflex should work if you need to re-seal the plate, but don't plan on taking it off again as I have never seen anythind stick as good as Sikaflex.