By continuing to use this site, you agree to our use of cookies. Find out more

Member postings for John Haine

Here is a list of all the postings John Haine has made in our forums. Click on a thread name to jump to the thread.

<< First < Prev 274 275 276 277 278 279
Thread: End mills in a drill chuck
05/10/2009 10:50:10
My tuppence worth.
 
I use my VMB mill as my main drilling machine (not enough space for another machine).  Moving the head between a suitable position for milling up enough to fit a drill chuck and drill takes a lot of winding on the vertical feed. 
 
Now, a trick I learned from Lautard's Machinist's Bedside Reader is, when you want to cross-drill a bar (e.g. for a set screw), put it in the milling vice and take a very light skim on the circumference with an end-mill, which creates a tiny land on the circumference, little more than a line.  You can make this even simpler by mounting the end mill in the drill chuck, using the lever feed to bring it down so the teeth only just contact the workpiece, locking the feed, and then taking your skim with no additional downfeed.  Now replace the end-mill with a centre drill and position it over the centre of the land.  This will allow you to locate the hole quite accurately enough for 99% of cases with no need for wigglers, cross drilling jigs or whatever.  Putting the end-mill in the chuck saves winding time and is fine because the cut is absolutely minimal.
 
John.
Thread: Just starting
04/10/2009 09:53:26
I am adding CNC to a Super-7, generally following Tony Jeffree's approach.  However it isn't so easy to convert the S7 cross-slide (at least the pxf version) as the bracket bearing design is very different, and the feed screw expensive to replace if I mess up!  So I have made a new feed screw and nut, as well as bracketry, so I can fully restore the machine if necessary.  Also on the leadscrew, I've simplified the addition of roller thrust races.  Just adding the mounting plate for the leadscrew stepper motor, when that's done I'll post some photos to the site.  Actually installing the PC and wiring up is going to take a major workshop reorganisation!
 
John.
Thread: Wheel cutting
01/10/2009 15:28:57
My understanding is that on imperial lathes the cross slide calibration corresponds to the actual movement - feed in .01 inches indicated and the X-slide moves .01, but it takes .02 off the diameter.
 
On the metric lathes I have used, including my own S7 and a 254, on the other hand, the calibration corresponds to what the lathe takes off the diameter, so the slide moves only half what is indicated.  Personally I find this absolutely fine and logical, but I can see trouble coming when (and if ever) I use an imperial lathe!
 
John.
<< First < Prev 274 275 276 277 278 279
Magazine Locator

Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!

Find Model Engineer & Model Engineers' Workshop

Sign up to our Newsletter

Sign up to our newsletter and get a free digital issue.

You can unsubscribe at anytime. View our privacy policy at www.mortons.co.uk/privacy

Latest Forum Posts
Support Our Partners
cowells
Sarik
MERIDIENNE EXHIBITIONS LTD
Shopping Partners
Subscription Offer

Latest "For Sale" Ads
Latest "Wanted" Ads
Get In Touch!

Do you want to contact the Model Engineer and Model Engineers' Workshop team?

You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.

Click THIS LINK for full contact details.

For subscription issues please see THIS LINK.

Digital Back Issues

Social Media online

'Like' us on Facebook
Follow us on Facebook

Follow us on Twitter
 Twitter Logo

Pin us on Pinterest

 

Donate

donate