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

Member postings for Martin Connelly

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

Thread: DTI base
01/04/2020 20:03:04

Henry, the link is just for a set of dovetail stems, a set of 2 for £6.60 so you can use your existing indicator with any metric mag base unit.

Martin C

Thread: Counterboring tools?
01/04/2020 19:09:12

Mick, I think 180 is finger trouble and Bo'sun meant 118 degrees..

Martin C

Thread: DTI base
01/04/2020 18:23:25

You can get spares from Mitutoyo if you have the part numbers for different stem clamps in metric and imperial sizes. When I was at work I had a Mitutoyo catalogue where I had sketched the various clamp blocks and their part numbers. I think the imperial one was 3/8", 1/4" and dovetail.

You can also buy dovetail stems quite cheaply so you could use a metric swivel clamp with your 1/4" stem indicator,

Dovetail stems

Martin C

Link added.

Edited By Martin Connelly on 01/04/2020 18:52:11

Thread: Gear Cutting - Pressure angle.
01/04/2020 17:27:29

The pressure angle is the angle of the teeth in a matching rack. If you had the means of rotating the gear blank and traversing the cutter at the correct rate you could cut gears with a pressure angle determined by the cutter angle. Doable on a CNC mill with a fourth (A) axis but a lot of messing about compared to just using a suitable involute cutter.

Martin C

Thread: DTI base
01/04/2020 16:21:38

MichaelG, I think my issue with the snake neck was not so much the rigidity of it but its lack of flexibility in positioning.

Martin C

01/04/2020 15:49:26

Henry, not easy to see in the photo but the base has Mitutoyo on it. You can't see the face of the knob but that also says Mitutoyo.

Martin C

Corrected spelling.

Edited By Martin Connelly on 01/04/2020 16:05:21

01/04/2020 12:13:49

I would just add that my experience of the snake neck type (if we are talking about segmented type with a central cable to pull it tight and lock it) is that they should only be bought from someone who will refund your money if you are not happy with it!

Martin C

01/04/2020 11:42:44

This hydraulic one is my go to mag base unit.

img_20200401_113705.jpg

Martin C

Thread: Mill drill Y axis power feed
31/03/2020 11:49:53

Both x and y use the same basic motor assembly. The y unit has a bevel gear instead of the straight gear and a bevel gear is fitted in place of the hand wheel on the y axis, straight gear on the x axis. The y axis unit mounting bracket replaces the machine's original bracket and has a bearing to support the leadscrew.

Remove the y handwheel and bracket. Position the drive over the leadscrew and fix to the machine. This may be a problem if the holes do not align. It may need some new holes drilling and tapping and they may be close to existing holes.

Fit bevel gear to leadscrew and secure, fit supplied cover. Fit limit switch to machine, this may also require some drilling and tapping or may even require a spacer.

Points to note, this unit may hang below the existing machine and may protrude behind the front face.

Most people only power the x axis because the y axis has less travel and is often not moved during machining, only when the tool is clear of the work. This makes it an expense most people can do without.

Martin C

31/03/2020 10:10:21

If you clarify what you want to know in more detail I can probably answer your questions or take some photos. Vague questions will only get broad answers or clutter in the thread.

Martin C

Thread: Muncaster No1 with Reverser BUILD & DRAWINGS
31/03/2020 10:04:12

I still have my Mamod SE2 from 1967. Like this it is a single ended single oscillating cylinder engine with a reverse/regulator lever.

Martin C

Thread: Mill drill Y axis power feed
31/03/2020 09:49:20

Me. I still have it but since I changed to CNC it is not fitted. It is as you say quite straight forward. Much better than hand cranking.

p1080951.jpg

Also fitted the one above that is mainly obscured by the guard, this is a Chester Super Lux.

Martin C

Thread: non-circular boring.. Literally - it is boring!
31/03/2020 09:41:57

Looks useful. I expect the maths is similar to what is used for single point turning of polygons on CNC lathes with the added complication of a rotating tool.

Martin C

Thread: Box-Ford travelling steady
31/03/2020 09:19:56

The usual options are to use thread gauges if you have some. If not then get either a piece of dowel or coiled paper/card and screw it in and out then measure the marks on the surface. Diameter and thread pitch will give a few possibilities to try.

Martin C

Thread: Myford Super 7 tailstock taper turning adjustment
30/03/2020 22:22:22

If you have a centre (or chuck, drill etc. ) with a good finish and no damage you can put that in the tailstock and use your plunger DTI on it. Check it in a couple of rotated positions to average out any error if you are not sure of its quality.

Martin C

Thread: Lathe
30/03/2020 22:13:53

Back off the tool before returning to do the next cut.

Martin C

Thread: Myford Super 7 tailstock taper turning adjustment
30/03/2020 16:27:48

It may be better to measure the bore rather than the outside of the barrel. Any non-concentricity will cause problems otherwise.

Martin C

Thread: Magneto spanner?
30/03/2020 15:52:41

Found a set like that when clearing out my father in law's after he died. He was a car salesman so probably picked it up at work. Don't know where I have safely stored them.

Martin C

Thread: New design of mains plug?
30/03/2020 15:47:24

It may be CE marked but there is a subtle difference in letter spacing between the EU mark and the Chinese Engineered mark.

Martin C

Thread: Myford ML7 4mm Screw Cutting
28/03/2020 09:03:46

Just a point of interest here. As pitch increases the speed of the carriage goes up for a given rpm. This can increase the torque required in the gear train and from the motor and the deeper cut requires more effort as well. This is possibly a good time to consider a spindle crank handle if you don't have one already.

Martin C

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

Latest Forum Posts
Support Our Partners
Warco
Allendale Electronics
Eccentric July 5 2018
Ausee.com.au
emcomachinetools
cowells
ChesterUK
Eccentric Engineering
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