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

Member postings for Alex du Pre

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

Thread: Split Infinitives
29/05/2017 21:19:41

Neil, I have read up on split infinitives once or twice and come to the conclusion that the so-called rule is an affectation with no grammatical basis. I do try to avoid splitting the infinitive, however, unless the meaning or readability requires otherwise, in which case I split without guilt!

Thread: What Electronic Projects are you working On
23/05/2014 20:46:51

I'm trying to get to grips with the Arduino. Hoping to use it as a basis for some control functions for my MkII Fifth scale model car:

http://www.amdengineer.com/mk-2-15-scale-rc-car/

possibly for an automatic gearbox, to control the lights, or even as an ECU for the engine! Endless possibilities!

Regards,

Alex

Thread: Lost wax casting
18/04/2014 20:31:10

All, many thanks for the interesting and helpful comments and links. Certainly no excuses not to get started now! I recently found a book entitled 'Lost-Wax Casting' by Wilburt Feinburg in the library, which is worth getting hold of. It's aimed at casting in third world countries so focuses on doing things with locally-sourced materials (mainly clay and animal manure!) but some good ideas for those of us who like to do things with minimal expense. In fact I subsequently found a PDF of this book on the internet, but I am reluctant to give the link as it is probably not a legitimate copy.

Best regards,

Alex.

17/04/2014 22:03:30

Hi all,

The novelty of machining parts from billet is starting to wear off and I am looking to add home casting of aluminium to my repertoire of techniques, particularly lost wax casting. There does not seem to a lot on this topic in the forum so I was wondering if anyone has any experiences or advice that they would be willing to share. I'm thinking of going down the home-made gas fired furnace route.

Alex

Thread: Myford spindle alignment
21/05/2013 19:28:08

All - just following up on the above for those who are interested! I spent the evening examining the spindle thread following the suggestions above. I couldn't see anything wrong, but gave the thread plus those in the chucks a good brass-wire brushing - no improvement. I finally decided to fit a threading tool to the tool post and run this up against the spindle thread with the appropriate gearbox setting (rotating spindle by hand). This approach highlighted a significant bruise on the thread, which I 'screwcut' away. The result of this was that the jamming chucks and face plate now screwed on freely, hence this must have been the problem. How it happened, I dread to think! Tests with the DTI showed a much improved, but not perfect, run out.

I'm not sure I would have found this without your help, so thank you!

Alex.

19/05/2013 14:35:06

Gents, many thanks for the suggestions. I will have a closer look at the threads for embedded swarf and other bruising/damage. I will report back!

18/05/2013 20:21:47

Hi folks, I noticed my Super 7 chucks were visibly not seating properly against the shoulder on the spindle nose. Fearing a bent spindle, I clocked the shoulder and the parallel portion of the spindle but there was no measurable run out. Clocking a lathe test bar also showed nothing amiss with the spindle taper. I clocked the face of my 3 and 4 jaws and the faceplate and this showed a consistent run out at the same position relative to the spindle (the outside edge of the faceplate gave a TIR of 0.2mm). My threaded ER32 chuck gave the same results.

I have scraped and the male and female threads and can't find any muck in there, but the 4 jaw and face plate are very tight screwing onto the spindle; the ER32 chuck is free.

I suspect something wrong with the spindle thread, but can see nothing obvious. Do I dare run a die or threading tool along it? I could also pass a tap through the chuck threads to clean them up - is this wise?

I would be most grateful for any thoughts on what might be wrong and what I might do about it. I have some work coming up that requires a true running 4 jaw and faceplate. Many thanks for reading this!

Alex.

Thread: Laser cutting
31/03/2013 16:53:34

Many thanks for the suggestions. I am in Bristol and I am certainly not the person who comes up when you do the google images search as suggested above - sorry to disappoint you!

Alex.

30/03/2013 06:32:19

Hi all, can anyone recommend a laser cutting company who will cut up to 2mm steel sheet from my CAD drawings?

I couldn't find much on this topic in this forum. I would also be interested in any experiences of laser cutting.

Thanks!

Alex

http://www.amdengineer.com

 

Edited By Alex du Pré on 30/03/2013 06:33:09

Thread: Bandsaw Choice
31/12/2012 06:19:17

I also have a Warco CY90! It lives under the bench on the floor and is dragged out for use. I am going to make a wheeled trolley for it to make this easier. The bandsaw is a real time and effort saver, I have been very pleased with mine. The cut is reasonably smooth and accurate. It can't operate as a vertical bandsaw, unfortunately, but bear in mind that a convertible machine such as this will be quite limited in vertical mode as the width of the blade will only allow straightish cuts. As mentioned elsewhere in the thread, some home-made accessories to enable workholding of small items would be well worthwhile.

Thread: Engine design - water cooling arrangements
30/09/2012 06:41:00

Hi all,

I am designing a model four-stroke engine in single and four-cylinder versions. I am thinking about water cooling arrangements. Is it ok to have cooling water in direct contact with the iron piston liners; should I worry about corrosion and how would I seal the water-jacket/piston liner join?

The design has an allow cylinder block with cast iron liners.

Many thanks!

Alex.

Thread: mini mills - which is the best?
10/08/2011 21:01:59
Hi, I have an X3 milling machine from Arc Euro Trade. If you are interested, I have a short review of it on my personal model engineering website, www.amdcustom.com.
Just follow the link under Equipment Reviews.
I would also add to the review, that even a machine this size (500W motor, or so), REALLY struggles to drive a 10mm cutter through steel at anything like a decent depth of cut. It's pretty good with aluminium. You either need patience or a bigger machine if you want to do serious metal removal!
 
I hope this is of some interest.
 
Alex.
Thread: Lathe oiling
03/10/2010 10:48:47
Hi, is there a trick to getting lubricating oil into oiling points (i.e. those with spring loaded balls) on machine tools?  I have a pump action oil gun (from Reeves) but when I press the nozzle up to the oil point and give the handle a good squeeze, the oil just seems to splurge out.  Do I need a special nozzle, or am I missing something?
 
All advice most gratefully received, as ever!
 
Thanks!
 
Alex.
Thread: Supplier for shaft seals, lip seals
29/06/2010 15:43:02
Can anyone recommend a supplier for shaft seals, lip seals, o-rings and the like, ideally metric.  Need a company that can supply mail order, small quantities, cheap (normal model engineer requirements).
 
I need some square section o rings for use as brake piston seals, and oil seals for the gearbox and diff for my next model car project.
 
RS have some stuff, but are not specialist enough.  Seem to remember BSL as a supplier but have had little luck tracking them down.
 
All ideas gratefully received!  Thanks in advance.
 
Thread: Home Casting in Mazak
14/02/2010 10:12:30
Hello everyone! Some useful tips in this thread.  I have been wanting to experiment with aluminium alloy castings for a long time and was wondering if anyone had any experience or views of making the moulds out of plaster of paris or similar, for small castings, particularly with regard to whether it is compatible with alloy casting.  It strikes me that this would be less hastle than sand castings, potentially give a better-defined casting and give moulds that could be reused several, if not many, times.
 
I believe a similar approach is used in investment casting (?) and I can't see why it wouldn't work provided the mould was thoroughly dried out and had the relevant draught angles, vents, etc.
 
Any thoughts would be most welcome.
 
Best regards,
 
Alex.

Edited By Alex DU PRE on 14/02/2010 10:13:13

Thread: Lathe/Milling Machine combination
15/12/2009 14:08:19
Sorry for multiple posts - I got an error message but the postings were posted anyway!  Not sure how to remove them!
 
Alex.
15/12/2009 14:06:26
Geoff,
 
I have a Warco WMT 300 which is a similar combination machine.  You may be interested in my review of this machine which is extracted from my personal website (amdcustom.com).  I hope you will find this useful although it does tend towards the 'why not'!  I especially would highlight the issues about the gap between spindle and 'mill table'.
I bought the machine for use in my model engineering activities. The machine is very solid and robust. It is rather crudely made, but the finish is adequate in the important areas such as the ways and the machine table. I have been quite pleased with the machine but it does have some significant limitations. A combination machine such as this is very much a compromise from the ideal of having two separate machines. It takes a long time to convert it from milling to lathe operations and I soon got fed up with it and bought a separate milling machine. I would not recommend a combination machine such as this as you will get very frustrated using it. The good and bad points are shown below.
GOOD POINTS
 
Very solid and rigid. With sharp tools, a good turned finish is achievable.

Pretty good value.

I have always received good service from Warco and would recommend them.

The lathe has a good capacity and is capable of turning large work-pieces. The large spindle bore (25mm) is very handy.

The machine comes with a good range of accessories - faceplate, 3-jaw chuck, change wheels, fixed and travelling steady, centres - although a 4-jaw chuck is the first thing you will want.

The machine is built to reasonable accuracy. It is possible to work to a tolerance of +/-0.02mm without too much difficulty.

Good range of features - reversible motor and lead-screw, screw cutting, taper turning, etc.
BAD POINTS
 
The cutting tools that come with the machine are next to useless.

The gap between the milling head spindle and the cross slide is very large, even with the spindle fully extended. Unless you are using a very tall workpiece, some sort of raising block will be needed, which largely defeats having such a large machine table. This is a very frustrating feature and required extra equipment and much time to set up, and significantly reduces the functionality and usefulness of the milling/drilling fixture.

The machine is very noisy. The pulley bearings are rough and noisy, particularly in the milling head.

The need to change belts to adjust spindle speed is time consuming and frustrating.

Changing the gear-cutting gears is very time-consuming - the gears are very stiff on their shafts and are extremely difficult to remove. Brute force is often required. Because of this, I seldom resort to screw-cutting or using the power carriage feed. It just takes too long to set up.

Between-centres turning is all but impossible. The width of the milling table severely limits the movement of the carriage in the X direction (along the lathe bed). This means that if the cutting tool is set up to cut the left hand end of the work-piece, you cannot reach the right-hand end and vice versa. This is compounded by the fact that the carriage is prevented from traversing fully to the left by a lathe holding-down bolt, and the lack of significant overhang of the tailstock. Because of this, it is not possible to turn a constant-diameter (or tapered) shaft in one pass. This is a huge limitation.

The lack of tailstock overhang is a problem, which is compounded by the width of the milling table. In addition to the between centres problems (above), the tailstock has insufficient reach to allow drilling of a workpiece held in the chuck. This is compounded when the workpiece is short and a small drill or centre drill is used. I have got around this by using a MT3-MT3 extension sleeve but this does not resolve the between-centres problems - it also compounds the inaccuracy of the tailstock alignment and results in reduced rigidity.

There is some play in the carriage movement. I cannot remove this without over-tightening the gib-strips. This means that with the cutting tool mounted on the left of the cross-slide (as it must be) the tool cuts deeper when traversing the carriage from right to left (and vice versa). The effect is reversed for boring operations. This is not a big problem, but is an annoying niggle.

The 4-way tool post is a useful feature. However, it is not good quality, and repeatability of positioning is poor. For reasonably accurate work, it is necessary to re-measure the depth of cut each time the tool post is rotated. This makes production work unnecessarily time consuming.

15/12/2009 14:05:27
Geoff,
 
I have a Warco WMT 300 which is a similar combination machine.  You may be interested in my review of this machine which is extracted from my personal website (amdcustom.com).  I hope you will find this useful although it does tend towards the 'why not'!  I especially would highlight the issues about the gap between spindle and 'mill table'.

I bought the machine for use in my model engineering activities. The machine is very solid and robust. It is rather crudely made, but the finish is adequate in the important areas such as the ways and the machine table. I have been quite pleased with the machine but it does have some significant limitations. A combination machine such as this is very much a compromise from the ideal of having two separate machines. It takes a long time to convert it from milling to lathe operations and I soon got fed up with it and bought a separate milling machine. I would not recommend a combination machine such as this as you will get very frustrated using it. The good and bad points are shown below.

Good points

Very solid and rigid. With sharp tools, a good turned finish is achievable.

Pretty good value.

I have always received good service from Warco and would recommend them.

The lathe has a good capacity and is capable of turning large work-pieces. The large spindle bore (25mm) is very handy.

The machine comes with a good range of accessories - faceplate, 3-jaw chuck, change wheels, fixed and travelling steady, centres - although a 4-jaw chuck is the first thing you will want.

The machine is built to reasonable accuracy. It is possible to work to a tolerance of +/-0.02mm without too much difficulty.

Good range of features - reversible motor and lead-screw, screw cutting, taper turning, etc.

Bad Points

The cutting tools that come with the machine are next to useless.

The gap between the milling head spindle and the cross slide is very large, even with the spindle fully extended. Unless you are using a very tall workpiece, some sort of raising block will be needed, which largely defeats having such a large machine table. This is a very frustrating feature and required extra equipment and much time to set up, and significantly reduces the functionality and usefulness of the milling/drilling fixture.

The machine is very noisy. The pulley bearings are rough and noisy, particularly in the milling head.

The need to change belts to adjust spindle speed is time consuming and frustrating.

Changing the gear-cutting gears is very time-consuming - the gears are very stiff on their shafts and are extremely difficult to remove. Brute force is often required. Because of this, I seldom resort to screw-cutting or using the power carriage feed. It just takes too long to set up.

Between-centres turning is all but impossible. The width of the milling table severely limits the movement of the carriage in the X direction (along the lathe bed). This means that if the cutting tool is set up to cut the left hand end of the work-piece, you cannot reach the right-hand end and vice versa. This is compounded by the fact that the carriage is prevented from traversing fully to the left by a lathe holding-down bolt, and the lack of significant overhang of the tailstock. Because of this, it is not possible to turn a constant-diameter (or tapered) shaft in one pass. This is a huge limitation.

The lack of tailstock overhang is a problem, which is compounded by the width of the milling table. In addition to the between centres problems (above), the tailstock has insufficient reach to allow drilling of a workpiece held in the chuck. This is compounded when the workpiece is short and a small drill or centre drill is used. I have got around this by using a MT3-MT3 extension sleeve but this does not resolve the between-centres problems - it also compounds the inaccuracy of the tailstock alignment and results in reduced rigidity.

There is some play in the carriage movement. I cannot remove this without over-tightening the gib-strips. This means that with the cutting tool mounted on the left of the cross-slide (as it must be) the tool cuts deeper when traversing the carriage from right to left (and vice versa). The effect is reversed for boring operations. This is not a big problem, but is an annoying niggle.

The 4-way tool post is a useful feature. However, it is not good quality, and repeatability of positioning is poor. For reasonably accurate work, it is necessary to re-measure the depth of cut each time the tool post is rotated. This makes production work unnecessarily time consuming.

15/12/2009 14:04:10
Geoff,
 
I have a Warco WMT 300 which is a similar combination machine.  You may be interested in my review of this machine which is extracted from my personal website (amdcustom.com).  I hope you will find this useful although it does tend towards the 'why not'!  I especially would highlight the issues about the gap between spindle and 'mill table'.

I bought the machine for use in my model engineering activities. The machine is very solid and robust. It is rather crudely made, but the finish is adequate in the important areas such as the ways and the machine table. I have been quite pleased with the machine but it does have some significant limitations. A combination machine such as this is very much a compromise from the ideal of having two separate machines. It takes a long time to convert it from milling to lathe operations and I soon got fed up with it and bought a separate milling machine. I would not recommend a combination machine such as this as you will get very frustrated using it. The good and bad points are shown below.

Good Points

Very solid and rigid. With sharp tools, a good turned finish is achievable.

Pretty good value.

I have always received good service from Warco and would recommend them.

The lathe has a good capacity and is capable of turning large work-pieces. The large spindle bore (25mm) is very handy.

The machine comes with a good range of accessories - faceplate, 3-jaw chuck, change wheels, fixed and travelling steady, centres - although a 4-jaw chuck is the first thing you will want.

The machine is built to reasonable accuracy. It is possible to work to a tolerance of +/-0.02mm without too much difficulty.

Good range of features - reversible motor and lead-screw, screw cutting, taper turning, etc.

Bad Points

The cutting tools that come with the machine are next to useless.

The gap between the milling head spindle and the cross slide is very large, even with the spindle fully extended. Unless you are using a very tall workpiece, some sort of raising block will be needed, which largely defeats having such a large machine table. This is a very frustrating feature and required extra equipment and much time to set up, and significantly reduces the functionality and usefulness of the milling/drilling fixture.

The machine is very noisy. The pulley bearings are rough and noisy, particularly in the milling head.

The need to change belts to adjust spindle speed is time consuming and frustrating.

Changing the gear-cutting gears is very time-consuming - the gears are very stiff on their shafts and are extremely difficult to remove. Brute force is often required. Because of this, I seldom resort to screw-cutting or using the power carriage feed. It just takes too long to set up.

Between-centres turning is all but impossible. The width of the milling table severely limits the movement of the carriage in the X direction (along the lathe bed). This means that if the cutting tool is set up to cut the left hand end of the work-piece, you cannot reach the right-hand end and vice versa. This is compounded by the fact that the carriage is prevented from traversing fully to the left by a lathe holding-down bolt, and the lack of significant overhang of the tailstock. Because of this, it is not possible to turn a constant-diameter (or tapered) shaft in one pass. This is a huge limitation.

The lack of tailstock overhang is a problem, which is compounded by the width of the milling table. In addition to the between centres problems (above), the tailstock has insufficient reach to allow drilling of a workpiece held in the chuck. This is compounded when the workpiece is short and a small drill or centre drill is used. I have got around this by using a MT3-MT3 extension sleeve but this does not resolve the between-centres problems - it also compounds the inaccuracy of the tailstock alignment and results in reduced rigidity.

There is some play in the carriage movement. I cannot remove this without over-tightening the gib-strips. This means that with the cutting tool mounted on the left of the cross-slide (as it must be) the tool cuts deeper when traversing the carriage from right to left (and vice versa). The effect is reversed for boring operations. This is not a big problem, but is an annoying niggle.

The 4-way tool post is a useful feature. However, it is not good quality, and repeatability of positioning is poor. For reasonably accurate work, it is necessary to re-measure the depth of cut each time the tool post is rotated. This makes production work unnecessarily time consuming.

Thread: Milling on Myford
11/08/2009 15:22:12
Going back to the original question, you are unlikely to get away with a depth of cut of more than half a mm at a single pass using a half inch cutter in slot cutting mode in the Myford.  Probably much less.  This is based on my X3 milling maching (similar motor power) which would really start to struggle under these loads.  I hope this helps.  As a beginner, I had wildly high expectations of the depth of cut my mill could cope with.
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
emcomachinetools
Warco
cowells
EngineDIY
ChesterUK
Eccentric July 5 2018
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