Cutting fluid: tips to save your taps
We all know it, dealing with a broken tap can be a pain.
Although there are several ways to deal with it, drilling out a broken tap out is generally time-consuming, challenging and requires a lot of extra work.
How to prevent this from happening? Two magic words: CUTTING FLUID.
Cutting fluid is a (cutting tool) life saver in operations like tapping, reaming and drilling.
Drilling in particular calls for lubrication at the drill’s tip and flushing to eject chips from the hole. Without fluids, chips can bind in the hole, and average roughness of the machined surface can be twice as high as what is possible with a wet operation. Lubricating the point of contact between the drill’s margin and the hole’s wall can also reduce the torque required from the machine.
Although some alloys, like aluminum, are typically more forgiving due to the relatively low cutting temperature, it is generally better to use cutting fluid in any occasion.
What type of cutting fluid?
There’s definitely a great variety of lubricants out there that can be used. Some of them are more suitable for soft alloys, while some others are designed to perform on harder materials, like Titanium or Inconel.
Here are some of the best options available in the market and the material they are most suitable for.
Tap Magic Cutting Fluid
The classic. Probably one of the most used cutting fluids in the trade. Although the regular version is expected to work well on any type of material, we recommend using the Tap Magic Aluminum on aluminum parts to avoid stains.
3-IN-ONE Multi-Purpose Oil
Another pretty solid cutting fluid, and it’s been around since the 1800s. Works just as well as a lot of other fancier and more expensive fluids in the market.
Beeswax
Not exactly the cutting fluid that any machinist would imagine, but it’s cheap, and can be used in multiple occasions. Rub some of it on your tap and be sure that it won’t break.
BruteLube Cutting Tool Wax
Another effective multi-purpose wax. This cutting fluid – or cutting wax – works pretty well on harder materials like stainless steel or exotic alloys.
BOELUBE Machining Lubricant
Like the wax mentioned above, this cutting fluid works great on harder materials. A minimum quantity applied to any tool will keep any tool cool and make it last longer.
Anchorlube
Probably the best cutting fluid to operate on Titanium. Just apply a little bit of this magic fluid in the hole and this will prevent your tap from breaking.
Castrol Variocut Tapping Fluid
If you are going to tap a hole, this is what you want to use, Extends tool life and nearly eliminates broken taps. Works particularly well on stainless steel and copper.
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17 Comments
What ever happened to original Tap Magic
The fluid before “Imporved ” Tap Magic was introduced
What about Relton Rapid Tap for metal or Relton A-9 for aluminum? I have had great success with these. Also Viper Venom with it high sulphur content for heavy duty use.
You didn’t mention “Spray-Tap” cutting Fluid great stuff.
Moly-dee may work well in copper but I would make sure you clean out the hole really well just after you’re finished. I have found it will stain if you don’t clean it out well.
I’ve always used plain animal fat when tapping steel — Sheep fat is the best
Im 83 in my youh I used tallow, beef tallow from the butcher
GFWHELL
Great advice and supportive product information. Another good product particularly for tapping is ‘Temaxol’ a yellow past which loses viscosity as the temperature rises and then it runs into the gaps between tap / die. Works with drilling too.
Along the same line as beeswax, lard works well and is super cheap.
I can remember the original “tap magic” The one that had the cloronated “tricloromethane in it was the absolute best. They have yet to even come close to the cutting ability of ANY other brand / type. It was outlawed in the mid nineties because of it’s cloronated solvent base. I still have / use some of that tap juice, as I knew it was being outlawed and I purchased a small stock of it. When you mix it with 80% dark cutting oil and 20% “tap magic” you wind up with something that cannot be beat. It greatly extends the life of taps, reamers, and high speed steel, lathe form cutting tools. Like I said, nothing comes even close to the ability that this combination does. I think that this cutting fluid is still available because it was the thing for cutting exotic metals, like what is used in the aircraft industry. And at last count it cost about $40 a pint can. When I purchased my stock the price was about $30 per gallon. I think that I’ll try to find some of this stuff, just to see if it is still available.
I’ve used Tap Magic on almost everything. It’s like my best friend in the shop, and I’ve used Anchorlube on stainless steel process piping in which it gives off a funky smell. Good to know about 3-in-1 didn’t know that could be used as cutting oil.
Mixture of carecut and surrclean works best on drilling or reaming aluminium
I have found that a mixture of approximately 50% kerosene and 50% “lard oil” works extremely well for both taping and machining in most metals, doesn’t cost a lot, is readily available and is not corrosive nor staining to the metals, tools and/or machinery. It also cleans up easily and well and doesn’t, seem to have adverse effects on most people’s skin or allergies.
WD40 is an excellent tap / drill fluid on aluminium. I’ve also used Milk of Magnesium on 304SS.
Four years ago I bought a bottle of NAPA Cutting Oil. It has never failed to do a good job.
I’ve had very good success with both Anchorlube and Moly-D…..they are expensive, but you only need a tiny amount. they are both great for just about any Stainless steel work.
In a pinch, I’ve used automatic transmission (ATF), worked great!
I’ve always used an old bottle Cool Tool for tapping steel. Smelly stuff. Upon reading all the positive comments about Castrol Moly-Dee, I wanted to try it. However, I don’t want to take a requisition to the boss, because bringing any new lubricant or chemical into the building means we have to file MSDS sheets and keep the records forever. One would think with a name like Moly Dee, it probably has molybdenum disulfide powder (a common high pressure lubricant) in it. But I could not find Moly listed on the MSDS. I happened to have some of the very fine powder on hand. I mixed it with a small quantity of Cool Tool. NOT HELPFUL. Jammed up the tap real good.
Anyone have a bottle of Castrol Moly Dee? What are the listed ingredients?