Coolant Leak from CNC Lathe

Your seal is worn. Replace it.

DVader1000 thk, It leak out from the machine body to the floor area. it need a good silicon to withstand the coolant and the chip.

sb,thk i don't know whether i can get the sealants in singapore but anyway thk for you help i will try the method you mention if success i will let you know bye.

Hello,

Looks like we were on the same track, by the way you have a good answer. I see your knowledgeable answers frequently. It is a reason why this site is sooo! good. Best regards

Sb thk,you are very detail even on the supplier

GA sb. Sometimes you may want the silicone to skin over before assembly as a gasket. Especially if you may need to disassemble at some time.

To get epoxy to stick as a fillet, start clean and dry of course, apply a very thin coat at first. Use emery cloth to grind it into the surface. This produces fresh metal to the epoxy. Wipe it off with a dry cloth or paper towel, then immediately apply a thickend mixture (add colloidal silica or talc) and shape the fillet with a tounge depressor. A plastic freezer bag w/ a corner cut out makes a good applicator.

The other thing to try is 'Marine Goop' trademark really sticky stuff that will streach from here to Baltimore when dry, and never hardens competely. Lumber companies carry a similar Thiakol based caulk in clear tubes that also dries clear. I think that stuff is the best bet, but test for compatibility w/ whatever liquid first.

Infact some times what we do is just stick a wax paper (in fact it is not exactly waxed, it is some graphited _asbestos approx 0.2 to 0.3mm thick i know it is banned ) on the other surface (cut to profile and holes made) with some oil or grease (just to retain in place) and then bring in the RTVed flange on it.

GA from me.

If I had to pick one word that is the most important word in your post it would be "degreasing"......I think our OP has simply put sealer on the leak with no preparation....

What sealer is that can it withstand coolant and hot metal chip.

This is a bit problem .

Hot metal chip temperature almost no sealant can take (if dry)

However since it is going to be in panel, the exposeure to hot chips will not be direct (through the metal walls). Also with the coolant in, the temperature may not rise that much.

check RTV 732 upto about 200 deg C

http://www.4pcorporation.com/Silastic_732.asp

RTV 736 upto about 260 deg C, intermittent 300 deg C or so,

(check on the above page)

You have Motorsil D also (upto 300 deg C) but gap filling capacity is low.

We use some other one in turbine parting planes and can work upto 1000 deg C. But that is with very small gap filling capacity and may not be useful for this purpose.

In fact in our cases, RTV 736 is the best one. RTV 732 also is OK.

Black Silicone Engine Sealant. Aval. auto parts stores. Sez up to 400 deg. F

Take it apart and fix it right!

Have you Tried welding it?

If I am not wrong OP has leakage between the sheet metal (housings, panels etc) and the main machine body.

These machines are housed inside some 2-3mm sheet metal with view glass etc. Usually this joint leaks.

In fact in one of our new machines, there was a leakage. We opened and closed eith the RTV 736. And for last 3-4 months no further attendance was necessary.

The worst part is due to the bad designed of the un-named machine manufacturer, this collant through one place was finding its way into the hydraulic oil. Forcing us to change the oil twice in last one year

BTW- in most of the cases the area wherer it is fixed is cast Iron.

I have done two things. First, I used puddy to create a dam, which is what I would not recommend. After removing this puddy, a mold-like residue was left behind. After cleaning that off, I used RTV 6700 silicone rubber adhesive sealant. This worked fine, and is still working. I have not had any problems since I used this in August 2008.