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

Member postings for MalcB

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

Thread: Warco WM18 T Slot size
15/02/2017 08:59:36

My VMC has the same 14mm Nom slot width.

If you are thinking of a new clamp set then a little food for thought:

I bought the standard 14mm x M12 clamp set available for this T slot size.

IMO after using it for a while I found it overkill and rather clumsy ( big clamps etc ) for the table size, so I opted to buy the next size down M10 clamp kit and made 6 x new 14mm x M10 T-Nuts. I find this more suited for my needs and more a balanced/matched set for this size of table and machine size.

I have kept the first clamp set per chance it was needed and it has been just a couple of times, but only because I needed some addition studs and clamps for a double setup i had on the table.

Thread: Nice small lathe ( CVA )
14/02/2017 19:13:18

Yes, as Dave says, this one is quite similar to the Monarch 10EE which I have worked on and which was a first class toolrom lathe.

I have seen one or two of the larger versions of their toolrom lathes in other toolroms and machine tool dealers, they were reputed to be very good quality machines but never managed to use one. Never seen one of these shorter bed versions, but looks a nice machine to have.

In my earlier years CVA were more widely known for their automatic lathes. We had a whole shop full of their cam operated autos when i was at Ferranti Ltd.

Thread: Machining EN24T
12/02/2017 20:18:39

Hi Chris,

EN 24T and similars

Surface speed for HSS about 45ft/min.

Feed rates

Roughing for HSS about 0.005/0.006" per rev

Finishing for HSS about 0.002/0.004" per rev

At least 3 times or more faster for good quality inserts tooling.

Home workshop speeds here, not industrial

 

Edited By MalcB on 12/02/2017 20:23:49

Thread: Quality digital vernier calipers
12/02/2017 19:16:54
Posted by Neil Wyatt on 12/02/2017 18:22:25:

M&W do verniers at various price points. The top of the range are equivalent to Mitutoyo, but the mid-price ones are very good. In my test I also found the 'cheap as chips' ones from Machine DRO are nicer than supermarket ones - ideal for workshop hack.

On a budget, grab a cheap hack pair and a mid-price M&W for best. But I've been spoiled and now use the Mitutoyo* for everything (I really ought to use a cheaper pair for most stuff...)

Neil

* I actually had to reset the origin today, hadn't used it for a few weeks and it was slightly out. I think that's the second or third time in several months, which isn't bad.

I have bought the M & W one from DRO that Neil tested in MEW, based on being above the budget level and suitable for everyday use.

I bought it to ease up on the use of my Tesa 6"/150mm digital vernier which i have had for about 20 yrs now. Using the M & W more and more now and finding nice to handle for daily use.

For information

We bought a bundle of 20 x Tesa at work along side quite a few Mitutoyo digitals ( about 8ish). Again about 20 yrs ago. Throughout their useful life the Tesa actually showed consistantly better calibration results from an external cal laboratory. Not a lot in it but they were better. Dont know how the newer models would stack up today side by side.

There are a few Starrett digitals and dial ones now starting to appear which are allegedly still being made in the USA and which appear to be well priced against the Mitutoyo. I would be really interest to see how these perform as my Tesa will need replacing.

Thread: Boxford lathe gurus...
12/02/2017 09:22:05

I personally do not think its an ex Boxford factory fit for several reasons:

The dimple locations in place of more positive parallel pin locaters indicate to me it was intended for nothing more than angular marking out. A research establishment would not need to do this on a lathe. They would have much better equipment for this purpose. As others have said there is/are no other signs of provision for additional machining or work holding on the lathe to supplement anything else other than this.

It would more than likely be far more beneficial to somebody who did not have other means to provide indexing, does not have a milling machine and/or just has a good bench or pillar drill.

5 degree increments would be a good single incremental denominator for home workshop engineering, to supplement many subsequent drilling operations.

I do not think Boxford would clamp a locating block on the headstock directly on a painted surface, not good practise for any machine tool maker. I do think that Boxford if they had fitted the block, they would also have painted the block.

When this lathe was produced, good indexing equipent was very expensive and beyond the economical reach of many home engineers, especially in smaller proportions.

As others have mentioned, It was not uncommen for machine tool makers to supply a pot of paint with the lathe so could easily have been done by an owner.

For somebody building up their home workshop portfolio, lots of jobs like skimming the headstock, making the index plate, the location block etc could well have been done at their workplace as "foreigners".

My comments are in no way intended to be derogatory to the owner, in fact quite the contrary as for a Boxford AUD I think its actually right up there amongst the top ones i have ever seen, ( and owned ) especially in their original paint.

Having recently been on an invited factory tour of the Boxford factory I must say there is no resemblance to the historical pictures you see of their once main line production facility that was producing the machines that most people know them for.

I also respect the comments the OP posted about the Colchesters as I also had the round header Master and sorely missed it after I had my last Boxford AUD, such that I moved the Boxford on, in favour of a bigger machine.

Edited By MalcB on 12/02/2017 09:24:35

Thread: Economy Hit & Miss (possible build)
09/02/2017 18:02:38
Posted by Andrew Johnston on 09/02/2017 16:30:47:
Posted by Nick_G on 08/02/2017 15:12:17:

But nowhere online can I find out the bore and stroke of the rascal. Anybody know.?

According to the drawings bore is 42mm and stoke is 73mm.

Andrew

Yes, confirm my drawings showing same

08/02/2017 18:07:13
Posted by JasonB on 08/02/2017 16:36:26:

There is a guy down under that casts the parts for model ice cream churns though they would not be too hard to fabricate.

They were used to do all sorts of jobs, may be something here for your lady

J

Edited By JasonB on 08/02/2017 16:40:34

Is this on the wrong thread J ?

Thread: Our club closes 31 march such a pity
08/02/2017 15:53:31

Its highly unlikely they would sell the land because of future development opportunities, however they may be able to offer the option of a fixed period lease whilst they makes future decisions on it.

Thread: Economy Hit & Miss (possible build)
08/02/2017 15:42:12

Hi Nick,

My wife bought me the materials/casting kit last year for my birthday at Doncaster show. Better deal than online. Various interupting projects since buying, including lathe change, plus now final fettling, polishing and painting stage of my Stuart beam means will be able to start it shortly, ( next couple of months if nothing interupts again ).

Away from home until late Thursday but if you have not resolved by then i will check out the ( comprehensive ) manual you get with it and post details.

Malc

Thread: Using Toolmakers Buttons
06/02/2017 16:30:21
Posted by Andrew Johnston on 06/02/2017 16:27:02:

So it can be set, or indicated, when other button(s) are close by.

Andrew

👍👍👍

06/02/2017 16:23:46

The use of buttons goes back well before my time and its about 40yrs since I last used mine in industry. Mine were made in the toolroom amd were hardened and ground.

There were commercially available ones and which had one button longer than the others. I think the practise at the time was more or less to copy commercial ones.

The longer button was occasionally used when a particular hole was needed to form a datum position and identify it accordingly.

I do strongly suspect however, that this may well not be their intended purpose, as I said they go back in history some time. Perhaps others may know.

Edited By MalcB on 06/02/2017 16:24:35

06/02/2017 15:04:27

My two sets of toolmaker buttons: img_0825.jpg

05/02/2017 20:05:24

We used toolmakers buttons in the toolroom/toolroom inspection as follows:

Toolmakers making complex drilling jigs would mark out hole positions for the drill bushes using height gauges and the like in relation to the component to be drilled location surfaces and pads etc.

Toolmaker would drill and tap through each hole about 2-4BA etc where the drill bushes were to be positioned. Buttons would then be secured to each tapped hole ( plenty of clearance twixt buttons and fixing screws ).

Jig would be sent into tool inspection area/department.

Jig would then be very accurately set up by a tool inpector and all the buttons Precisely positioned accordingly.

Set up datums would be identified for the jig body.

Jig then moved on to jig borer.

Jig borer setting up to inspector identified datums.

Jig borer would usually set up true to each individual button one at a time.

Jig borer would then slot drill and then with boring bar finish to to suit outside diameter of slip bush for drill bushes.

Back into tool inspection for final checks.

By complex jigs, I refer to those where the jig borer found it difficult or impossible to get at the components location faces and pads etc directly.

 

Edited By MalcB on 05/02/2017 20:06:51

Thread: Bench Grinder
05/02/2017 17:11:32

Out of interest:

Has any body stripped any of the 3 phase bench grinders to see if their motors have the option of being wired for Delta?

Malc

Thread: Inverter vfd's do's and dont's
04/02/2017 15:40:19

Very interesting article, more to take in on the VFD learning curve.

A lot of info in there is covered in some of the manufacturers installation manuals, but there are quite a few manuals I have read that dont touch on a lot of its contents.

It would be interesting to see how many home installations have every power cable and every logic control cable running is steel tubing and how many are seperated by 12".

Thanks for the link John.

Thread: Warco VMC
02/02/2017 07:33:25

I cant believe Warco would do such a thing if they in fact fitted the readout themselves, the mind boggles.

Its certainly not what I think can be perceived as good engineering practise.

The scales are supposed to be held in correct alignment within a couple of thou.

They must not be bothered by the fact that at some time in the future the owner will need to replace them and try and get the scale back aligned, but heyho, its going to be out of warranty by then.

01/02/2017 21:14:52
Posted by Stuart Bridger on 01/02/2017 21:03:07:

Jumping back to the rubber protective sheet. I have just discovered that the Warco fitted DRO X-axis read head is mounted on top of the plate that that holds the bottom end of the rubber sheet.

This means that to get the remains of the existing sheet out to replace it. I will have to disturb the DRO installation which I really don't want to do. Further more it looks like the read head alignment is determined by the compressibility of the rubber??? I think I will be looking for an alternative fixing method that doesn't disturb the DRO.

Stuart, I find it hard to believe somebody actually fitted a DRO scale directly on top of the rubber. Personally if it was my machine, i would remove and re-fit the scale and reader assembly just for piece of mind. At a minimum i would remove its cover and clock up the scale to check it out before any real damage could happen.

01/02/2017 09:27:03

Clive,

Thanks for input and yes I will keep you all in the frame with results when I finalise settings.

01/02/2017 08:32:08

 

Posted by John Rudd on 31/01/2017 22:30:41:

Malc,

Does the Teco inverter have the ability to set a different frequency that is switchable using a digital input...,?

I have Teco inverter on my lathe ( a smaller version of yours, .75 hp) but havent really read the manual.....

If inverters had the flexibilty to set the frequency switchable from 0-50 and 0- to x hz it would make belt changing un-necessary if it could be changed by a switch.....

Something for me to look into......

Hi John,

Reading your question in conjunction with Clive response as well.

I have two Teco inverters that i have installed. Both models have a variable frequency potentiometer on the face of the inverter, like on the more expensive Inverteks.

I have a 2.2kw Teco EV series on my Harrison M300. Its a late machine (2003) which has  more contactors and overload protectors than the earlier models. MEW 145 covered a conversion for mine. The logic control to the inverter in this article seemed overly complex so i did my own circuit diagram, got my electrical wizard friend check it, went ahead and rewired it all to utilise all the machine controls and interlocks, not really wanting to do any with the inverter, which i left set at 50Hz max. I can still use the pot on the front to vary speed if needed, but the M300 has such a good speed range i think it will never be necessary.

The Teco I have just installed on the VMC. is the L510 series 1.5kw model, which is to be used opposite to above in that i am using frequency range to change speeds.

I do not understand what you would gain by having switched frequency ranges. If you programme the inverter  to use the potentiometer with a speed range from say 0 to 100Hz why would there be a benefit switching in between? I cannot see in the manual that you can use different ranges, only a min and max, but does not mean i have not missed it.

 Its as Clive has established, setting a wide frequency range and then setting the belt position to achieve the optimum compromise of max speed, lowest speed, satisfactory motor cooling at lower frequency and minimum amount of belt changes if needed.

If its an issue of knowing exactly what speed you are doing and your inverter does not have the ability to display revs then its still really simple.

Once you are satisfied with the fixed initial belt position,  buy yourself a digital tachometer like I just have.

You can get a decent one for not a lot of money. Use the tacho and at each of the potentiometers markings, take a reading and the do yourself a chart of frequncy setting vs RPM, which is what I would have done had I not got the parameters to do this on the Teco.

To generalise a little.

One of the big learning curves for me is using inverters and I have a lot to learn yet. When I first started looking at and learning about them, I download quite a few manuals ( and i mean quite a few ). I found some very easy to tead and follow right thru' to those that were megga difficult to understand. Loads of Youtube videos watched, each time gleebing a little more understanding.

I actually found the Invertek and Teco not to difficult to follow and these were makes high on consideration list.

Edited By MalcB on 01/02/2017 09:20:07

31/01/2017 21:53:36

John,

Yes it does and the thermister block is there in the terminal box as well. It has ability to display the temperature but I am not sure if is able to do any further controlling. Its unlikely I will use it, but I will research it further out of pure interest and learning.

Clive,

Very interesting, If I opt for the lower 1380RPM setting at 50Hz the top speed hits about 2100 RPM at 75Hz or 2200 if i squeeze it a bit. May be better running with this option with a belt change for higher speeds than 2100/2200. Will give it a few weeks and swap over. I do use wigglers and edge finders.

 

 

Edited By MalcB on 31/01/2017 21:54:19

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
walker midge
Warco
emcomachinetools
cowells
Eccentric July 5 2018
rapid Direct
JD Metals
Dreweatts
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