Kroil and/or 2-cycle oil

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10-03-2010, 04:05 PM
Marlin Junky

Kroil and/or 2-cycle oil

Generally I don't have any problems with boolit release from ferrous molds after they've been "broken in" (deburred and stuff) but I may be moving to a more humid climate and was wondering if Kroil oil can double as a good rust preventative and mold lube. When I say mold lube, I'm referring to the wear points (sprue plate and alignment pins). I like to cast at a relaxed pace with my pot near 800F. Also, what is used to dissolve Kroil oil?

I was also thinking about using 2-cycle oil to protect and lubricate but I'm not sure what dissolves that stuff either... in case I need to clean the cavities squeaky clean.

Thanks for your input,
MJ
10-03-2010, 05:04 PM
No_1

Carb cleaner does the trick. Just find the cheap stuff at Kmart or Walmart, lay into a supply of it and forget your worries. I live in Florida and coat all my moulds with a general purpose lubridat / preservative when I am finished with them. When it is time to use them again I spray them down with carb cleaner, wash them good with hot soapy water then spray them down with carb cleaner again. Once I preheat my moulds and they are good to go for casting.

Robert
10-03-2010, 05:32 PM
sqlbullet

I prefer two cycle oil to kroil. Generally I can burn it out if I get any in the cavities in a few castings.
10-03-2010, 07:13 PM
Marlin Junky

Quote:

Originally Posted by sqlbullet

I prefer two cycle oil to kroil.

Really?

Is there any particular form or brand of 2-cycle oil that has your preference?

I though I was reaching way out there because I'd never heard of anyone using 2-cycle oil. I just thought I'd try it since it holds up under the heat and pressure of a Yamaha. I don't know if it will protect the finish of my Lyman, RCBS and SAECO molds from corrosion though. I'm assuming it's pretty economical because most the commercial grade weed wackers and such use it. I wonder how it would mix with beeswax or mircocrystalline wax.

What I'm looking for is a single lubricant that I can apply a thin coat to the mold for protection during storage, wipe out of the mold cavities and vent lines before casting and lube the spure plate and alignment points during preheating and casting.

MJ
10-04-2010, 10:23 AM
sqlbullet

I should clarify. I use it as a mold lube on my molds (all aluminum). I apply sparingly with a cotton swab to the alignment points, and then brush it over the bottom of the sprue plate.

The first few castings after hitting the sprue plate have voids and wrinkles consistent with a little oil contamination, but it goes away. From that point on for the next 100-200 casts, I don't have any issues with smear, even if I cut the sprue a touch early.

As far as storage, I think any way you go, you are going to have to clean the cavity well before casting if you put oil in there. I had read the threads about kroil in a mold, and tried it, but was less than impressed myself.

I am not sure that 2 cycle oil is really the best rust preventative. Automatic Transmission fluid is supposed to be pretty good a rust prevention. Since you will be having to clean it off anyway, I would probably look for the best rust prevention that can be reasonably removed.
10-04-2010, 01:01 PM
Wayne Smith

Store your molds in the air conditioned house, don't leave them out overnite, and don't worry.
10-04-2010, 06:51 PM
montana_charlie

Quote:

Originally Posted by Marlin Junky

was wondering if Kroil oil can double as a good rust preventative and mold lube.

It really isn't much good for either purpose.
It's a penetrant, not a lubricant.

CM
10-04-2010, 07:28 PM
waksupi

If you want a rust preventative, go to Napa. Get a can on Mac's 1370 Chain and Cable Lube. Better than Fluid Film so far in my experience. Also good for lubricating your emergency brake cable, which is what I originally got it for.
10-04-2010, 07:43 PM
XWrench3

2 cycle oil is designed to disolve in gasoline. gasoline does a fine job of disolving it. as for kroil, i have no idea, but brake cleaner will disolve most petroleum products. M.E.K. will disolve almost anything that isnt stone or metal.
10-04-2010, 09:36 PM
GabbyM

Kroil will not lubricate or protect against rust. It's more of a solvent than anything. Best thing you can use to loosen old threads. I've tried it on mill fixtures and form dies in the shops where we had it in gallon cans. Didn't work at all against rust. Tool crib handed it out for air tool oil once. After all it's read right?? Within a week the air grinders it was used in had lost there bearings. There are some claims on a can of KROIL that just don't hold up. ATF makes a good rust coating for guns. For moulds I use a metal protectant spray. Amsoil product MP. I've used the CRC brand from shop store room that did not work near as well. Amsoil MP takes ten or fifteen minutes to burn it out of a mould. That's the down side. But it leaves a nice blue. Molds soaked in KROIL takes a short time to burn out. Leaves a nice blue but the blue burns out after a couple hours.

I have a spray on wax diluted in alcohol that Magma sells. Works nice but to expensive. Wish I knew what the wax was. Bullplate lube is the best stuff for sprue lube.
10-04-2010, 09:53 PM
Tom W.

RemOil.....
10-05-2010, 02:01 PM
Marlin Junky

How about this stuff for mold lube and maintenance:

http://www.amsoil.com/StoreFront/hpi.aspx

MJ
10-05-2010, 02:25 PM
John Boy

Quote:

If you want a rust preventative, go to Napa. Get a can on Mac's 1370 Chain and Cable Lube. Better than Fluid Film so far in my experience.

Eezox, 9 Month Test ... http://www.theopenrange.net/forum/in...p?topic=5457.0
Eezox v Fluid Film, 10 Month-11 Days Test ... http://www.theopenrange.net/forum/in...p?topic=6291.0
10-05-2010, 02:55 PM
Marlin Junky

Actually, I'm not just looking for a rust preventative... I'm looking for a high temp lube that provides corrosion resistance.

I think I'm going to pick up a quart of Pennzoil Marine 2-cycle oil before my next casting session since it's a heck of a lot easier to find than AMSOIL, cheaper and probably very similar to AMSOIL HP Injector.

MJ
10-05-2010, 04:16 PM
montana_charlie

Quote:

Originally Posted by Marlin Junky

I'm looking for a high temp lube that provides corrosion resistance.

Define 'high temp'...

You think of 2-stroke oil as a 'high temp' lubricant/
But, it only has that reputation because 2-stroke engines run somewhat hotter than water-cooled ones.

When temperature climbs above 250 degrees ii starts to become detrimental to gasoline engines...which is where (even) 2-stroke oils operate.
But, the oil in a 2-stroke is only subjected to the operating temperature of the engine for about .02 seconds...before it it pumped to the combustion chamber to be burnt and blown out the exhaust.

If you want an oil that can resist 300 to 500 degree mould temperatures, and do that for a hour's worth of casting, what makes you think any motor oil can?

On the other hand, if you want something to prevent rust in a cavity, you will certainly(?) be cleaning it out before the casting session. If it's gone before the mould heats up, a rust preventative doesn't need to be a high temperature product...does it?

CM
10-05-2010, 06:07 PM
Marlin Junky

Quote:

Originally Posted by montana_charlie

If you want an oil that can resist 300 to 500 degree mould temperatures, and do that for a hour's worth of casting, what makes you think any motor oil can?
CM

I'm hoping the oil will burn off to leave a lubricating film behind.

What do you use to lube your molds during a casting session?

MJ
10-05-2010, 11:18 PM
montana_charlie

Quote:

Originally Posted by Marlin Junky

What do you use to lube your molds during a casting session?

I used to use anti-sieze compound for screw threads and all friction points...and spray graphite for the sprue plate.
Now, I just use Bullplate for all of that.
CM