Alluminium cuting fluid

I need to drill & tap some 3/8-16 UNC blind holes in 6061 aluminium heat treated to T6 Just ordered a new set of taps and a 5/16" drill .......... For ferrous & stainless I use Molyslip MWF
Many moons ago when I worked in engineering the advice was always to use White Spirit or Turpentine (or paraffin at a push) as cutting fluid for aluminium. I did a quick Google to see if things have changed, and people now seem to suggest that WD40 is the preferred cutting fluid ... anybody any particular views on this
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
"Rick Hughes" wrote in message

WD40 works well for most aluminium alloys, both for turning and tapping
Andrew
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Saturday, January 2, 2016 at 5:50:27 PM UTC, Rick Hughes wrote:

Ta .... I have a gallon of, I use it for de-watering ... it's good for that. Funny that it's bought by many for anti-rust or dismantling and its not that good for those tasks.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 02/01/16 20:23, Rick Hughes wrote:

I prefer Duckoil, does a far better job than WD40 IMO at keeping rust off and seems a good lubricant for aluminium cutting as well. I buy it in the gallon size and use a trigger spray applicator although it can be bought in aerosol it works out more expensive. I mentioned it to someone I know that used to use WD40 and he is a convert.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 03-Jan-16 5:53 AM, Rick Hughes wrote:

WD40 is fish oil with a perfume added to get rid of the stink .
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 03/01/2016 04:39, Bluey69 wrote:

I have read in several sources that WD40 is White Spirit with a small % of mineral oil (which explains why it is good as a cutting fluid for Ally) Don't think it's fish oil.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 06/01/16 13:39, rick wrote:

Whale oil be blowed! (I'd never heard of the fish hypothesis)
--
Rusty Hinge
To err is human. To really foul things up requires a computer and the BOFH.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sat, 2 Jan 2016 09:50:26 -0800 (PST), Rick Hughes

For years I have used kerosene (parrafin) mixed with a little non-sulfur containing cutting oil. The type used for general metal cutting. I then switched to "Lamp Oil", where in the US is basically deodorized kerosene. Works as well but doesn't stink. But if you only have a few holes to do and WD-40 hanging around then it will work fine. And in small doses doesn't stink. Eric
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 1/2/2016 12:50 PM, Rick Hughes wrote:

Alcohol works nice on blind holes with easy clean up and chip removal. Why the coarse threads over fine???
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 03/01/2016 20:22, Jimmy Alpha GeD wrote:

There are 3 existing tapped holes that are UNC just adding 2 more so they need to match .... maybe it is thought UNC is a better thread for holding in 6061.
The item is US marine industry, and UNC does seem to be the most common thread in US Marine .... Mercury & Mercruiser engines for example all use UNC.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 1/6/2016 8:47 AM, rick wrote:

Fine thread just gives more threads and is easier to tap, but if you're tapping half inch down you'll have lots of threads. Also if you are going to use a pilot drill you might want to look into dubbing the 5/16 drill so it doesn't want to screw into the the pilot and brake the drill.

I myself just like fine threads for aluminum, but I mostly did thin stock.
jim a
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 07/01/2016 02:35, Jimmy Alpha GeD wrote:

>"you might want to look into dubbing the 5/16 drill"
I have no idea what that means, can you explain further.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 1/8/2016 3:32 PM, rick wrote:

It's grinding the cutting edges flat so it doesn't screw into the hole, here it is shown at this youtube link, <
https://www.youtube.com/watch?v=8Ri6poVpQM8
trust me a sharp small
drill not dubbed like your 5/16 may break or f'up the hole if you use a pilot hole. I'd grind small flats on the cutting edges and do a test hole on scrap first. We call that dubbing a drill in the states.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 10/01/2016 16:38, Jimmy Alpha GeD wrote:

Thanks for explanation .... these are not thru holes .... not sure if that is relevant I was always under impression that you keep your drills sharp ? never seen this before.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 1/14/2016 4:59 PM, rick wrote:

The dubbed drill is still sharp, just has a small flat lip much like on a concrete drill bit. Experience is the best teacher, try on scrap first no matter how you do the drilling. Oh, the reason for the oil is so the aluminum chip doesn't bond to the drill, not so much as a coolant, so be sure to use it. Best of luck and please report back. lol
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Wd40 is simple to obtain and still has the same hydrocarbons it used to. White spirit has been got at by the elf of safety, v and is no longer bad for your skin, which means it doesn't work as well...
Any light oily fluid will work ime. I think I used trefolex last time as it was handy.
Dave
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Wd40 is simple to obtain and still has the same hydrocarbons it used to. White spirit has been got at by the elf of safety, v and is no longer bad for your skin, which means it doesn't work as well...
Any light oily fluid will work ime. I think I used trefolex last time as it was handy.
Dave
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.