Here is a list of all the postings Windy has made in our forums. Click on a thread name to jump to the thread.
|Thread: No turning for me this weekend|
Something I came upon a while ago while doing the valve timing on an old ex racing friends 650cc Triumph.
It would not run properly.
I asked if the Lucas magneto was ok and was told he had fitted new carbon brushes to it.
The erratic running was traced to the magneto brushes being very soft material and coating the slip ring.
According to a magneto specialist this was a common problem with some of the carbon brushes from India.
As many of the motors we use are far Eastern are the carbon brushes of a suitable standard for prolonged use?
Edited By Windy on 16/04/2011 15:13:51
|Thread: New I/C diesel project - ETA15d-x2|
Great to see your IC being made.
About 'Simply Bearings.co.uk'.I bought bearings in 2009 from them and advice and service first class.
Edited By Windy on 01/04/2011 13:24:27
Edited By Windy on 01/04/2011 13:25:52
|Thread: Case Hardening|
Thanks Terry have ordered Kasenit from Midway UK.
I see Kasenit number 1 and 2 are advertsed on some sites.
Seen what steels Kasenit number 1 is used for but what is number 2 used for?
Thanks for a great forum.
|Thread: Car Boot Sales|
I have found numerous good quality tools at car boots.
Last month at a local autojumble amongst a pile of rusting machine reamers I found two boring and facing heads.
Narex VHU36 the other a Wohlhaupter UPA3 £18 purchased the pair.
The Narex had a siezed locking pin and required some new gib screws.
A complete dismantling revealed hardly any wear.
The Wohlhaupter UPA3 had an integral plane shank that had been bodged to fit a large taper to.
On strip down very little wear was evident.
A pair of new gib nuts were made and a new taper grafted on the shank.
The Internet has provided me with diagrams of the parts.
If you are prepared to do a bit of reclamation its amazing whats available at reasonable prices.
Edited By Windy on 05/03/2011 23:34:52
|Thread: Warco milling machines|
I am thinking of buying a new Warco milling machine, probably a VMC or WM18 when the Harrogate show is on.
If any member could advise me on any shortcoming on them I would be most grateful.
The VMC milll would need an additional spacer to increase the height above the table, does anybody supply them or will I have to make one?
WM18 mill has a variable speed motor are they reliable?
At the moment I have an old Warco round column mill thats seen better days.
Any comments welcome.
|Thread: Motor Valves, What are they good for?|
Hi James, I have used numerous car and motorcycle exhaust valves on my flash steam engines.
Some have been made of 21/4n and nimonic steel plus others that I do not no the specification of.
Tough but can be machined with sharp HSS tools.
If the valve material is going to be used in a high performance engine make sure the valve you use does not have a welded on head as they sometimes can break off.
Edited By Windy on 11/04/2010 09:57:24
|Thread: Is the 4" Rotary Table at ArcEurotrade better than SOBA ?|
I have bought numerous new and secondhand small tools etc from Ebay.
A word of warning on the second hand sales, study a photo very carefully some sellers are very economical with the truth and if not as advertised demand money back.
If seller refuses tell them you will notify Ebay, many of these sell regulary and most do not want a bad feedback or to be banned from Ebay.
|Thread: Lower Price Optical Rev Counter Accuracy|
Thanks all for your comments it seems the cheap optical one comes out tops.
Have tried reflective tape, white paint and black tape on a bright background as suggested, the readings on the 2800rpm motor where all very close to 3000rpm.
Will borrow my mates old ignition strobe and do a comparison.
Edited By Windy on 22/02/2010 23:58:27
I have bought a new £26 optical rev counter and would like to check the accuracy of it at high rpm and how can it be checked in a home workshop.
It has been checked against various electric motor nameplate speeds and the readings are as followers, these motors are not under load.
Examples 2,800rpm motor, minimum optical reading 2,993rpm, nearly 200revs out.
My mechanical counter reads 2850rpm
An article that I read on speed testing of electric motors says a strobe should be used?
A visual slow speed test was done on my lathe i.e. Slowest back gear was selected and a mark placed on the chuck backplate then rpm counted against a stopwatch for a minute.
The lathe speed plate says 50rpm, my stopwatch test gave just over 62rpm, the optical rev counter read 62.4rpm and a mechanical rev counter said 60rpm
My mechanical counter only goes to 20,000rpm.
At slow speeds the optical counter is reasonably accurate but when the revs go above about 2000rpm there are large discrepancies compared to the mechanical counter.
Any suggestions or are these lower priced optical rev counters unreliable at high speeds.
Another identical rev counter was supplied and it reads the same.
Edited By Windy on 22/02/2010 17:00:45
Edited By Windy on 22/02/2010 17:01:53
Edited By Windy on 22/02/2010 17:05:24
Edited By Windy on 22/02/2010 17:11:16
|Thread: Viton rings|
Hi Meyrick, I haven’t had much to do with Viton O rings of that size as alternatives to metal piston rings but would PTFE ones be any better there is also Kalrez it has the same advantages as Viton but it has greater chemical and temperature resistance. However Kalrez is considerably more expensive than Viton.
Edited By Windy on 17/02/2010 01:06:41
|Thread: Heat Treatment of I/C Cylinders|
Hello Ramon, a slightly different type of 2-stroke piston engine my flash steamer revs to 15000 with no load 10,000 under load.
I use an unhardened cylinder liner of en24t and use a cast iron dykes ring on a cast iron piston.
The wear is minimal after 2 seasons of competitions.
|Thread: Small hole drilling in stainless steel|
Sorry about shooting off at a tangent from small hole drilling.
Amazing that something that Gustaf de Laval in 1888 did for use on an impulse steam turbines is now used on the majority of rocket engines today.
One of my 1911 books shows a gas turbine design not too different to a modern one.
It seems that a lot of mechanical and theoretical ideas are very old but with modern materials become a reality.
I have a great deal of information on the delaval nozzles for impulse steam turbines and am using that as a basis for the design of them.
At the moment the flash steam generator has to be proved adequate.
Edited By Windy on 14/02/2010 20:17:49
Edited By Windy on 14/02/2010 20:21:49
Hi Meyrick, was told it would be supersonic by a friend who has just done nozzle tests on his full size flash steam generator.
We are both going down similar paths one miniature the other full size.
Ear defenders required, hope the neighbours are out its bad enough running the piston engine.
Edited By Windy on 14/02/2010 14:48:32
Edited By Windy on 14/02/2010 14:50:50
Thanks Stewart, a very useful link as was mentioned there are other ways to drill very small holes.
As one member of that link said (I need to drill 0.004" holes, and I think the recommended speed is around 95,000 rpm to keep the drill bit rigid enough without having to worry too much about the pressures that need to be applied for it to drill thru the piece part, drill bit speed is the secret to small hole drilling.)
To do it this way I would have to make a high speed-drilling spindle.
All the nozzles have now been done and have just the test stand to finish.
Hopefully next week there will be a test session to check pressures on combinations of nozzles, temperatures, speed of pumps and quantities of fluids used etc.
I have found that keeping a video record of testing has been very useful as sometimes with all the action of bench testing which is only for a limited time I can miss things that could cause problems when in competition.
Edited By Windy on 14/02/2010 10:05:27
|Thread: Turbine Blades|
V8Eng mentions the gtba and I found them very good at giving practical advice.
I forgot to mention an article by D.H.Chaddock (21 December 1950) about a turbine blade copying attachment and another one by L.K.Blackmore (ME 31 January 1957) on turbine blade cutting for an experimental gas turbine.
The L.K.Blackmore attachment might be more suitable for your turbine, if you require the article I could send you a copy.
Edited By Windy on 11/02/2010 20:04:37
An old book that MAP used to sell (ISBN 0 85242 712 3) Model Boat Propellers has a chapter on ways to make marine props simply, also ways to calculate the various angles etc.
It does not answer your question how to mill one but gives the basics of design.
Another very old one The Book of Modern Engines has a volume devoted to all types of turbines
Edited By Windy on 11/02/2010 17:00:08
Edited By Windy on 11/02/2010 17:01:39
Hi James, I make 4"Ø 2 bladed props out of the solid for my hydroplane out of high tensile steel.
If you have an idea of the shape of the blades and the various angles you could machine a series of straight blades.
Set the blank at the root angle of the blades and use a cutter with a rounded end so no sharp corners. Using a dividing attachment mill the number of parallel-sided blades required making sure they are a bit longer than required.
Draw a diagram of the propeller, decide the pitch and measure the angles at various radiuses.
Make some sheet metal templates of the various angles.
Then twist the blades with a suitable tool checking the angles with the templates.
When satisfied turn to the diameter required and with rotary burrs, files etc. create an airfoil section to the blades.
You could set the blank at the angles required on a rotary table and go in steps with a round nose mill but that is very time consuming and will still have to finish by hand.
The material you use will have to be something that can be twisted without cracking.
Some of the turbines are cast or edm.
Hope this might be of some help.
Edited By Windy on 10/02/2010 13:46:20
Edited By Windy on 10/02/2010 13:46:58
|Thread: Small hole drilling in stainless steel|
Thanks Chris for the reply, Dag Browns article is very interesting.
You can get some very small carbide drills that the electronics industry use but they are as you say very brittle.
What I am making is a set of converging-diverging nozzles for a test rig to check if my steam generator will be adequate for my turbine, a problem the full size steam record car had.
I do step drill the nozzles then ream with a homemade taper reamer 0.1044”Ø to 0.015”Ø a bit like an injector.
If the small hole is not dead centre with the step-drilled holes the reamer suffers it is also in hexagon bar.
If I could trust the hexagon bar to be concentric it would be reversed in the chuck and the 0.02”Ø would not have to be as deep?
There are only a few more nozzles to make then I will be having a test firing, have been told that the steam from the nozzles can be very noisy and I will probably need ear defenders?
Edited By Windy on 10/02/2010 03:46:00
I am drilling holes 0.020”diameter x 0.5”deep in 304 stainless steel and would like thoughts on ways to do this, some of the holes that I will also be drilling need to be 0.010”diameter x 0.5” deep in the same material. At the moment the drills are held in a pin chuck in a loose tailstock chuck and I slide the pin chuck by hand in a pecking action with coolant at the work piece. At about0.25” deep it starts to get difficult not to break the drill. Carbide drills have been tried but don’t think my lathe is fast enough. Also the drills that I am using need to be sharpened often, ideas on sharpening very small drills welcome. The way that they are sharpened at present is by hand with a fine diamond hone and magnifying glass. I did wonder if I used a mini drill mounted on the top slide if it would be better for the very small drills.
Any suggestions, articles to look at etc. welcome. Windy
Edited By Windy on 10/02/2010 00:07:45
Edited By Windy on 10/02/2010 00:09:11
|Thread: Prescription Safety Specs|
Hi Mark as a person who has to use reading glasses for close up work, find an optician who will supply safety spectacles with certificated prescription safety lenses.
Shop around as I had difficulty finding suitable safety frames, as some stock frames might not be a good fit.
Dollond and Aitchison did a reasonable job matching side frames etc. so they where comfortable.
Some Opticians are only interested in selling what they have in stock.
Problem I have that for extremely fine jobs even reading glasses give distorted vision and have to look with the naked eye (no protection).
About 2.5 maximum inches from my eyeball and I can see minute detail.
I need some plain lense safety goggles that do not protrude far from my face; normal safety goggles protrude too much.
Any suggestions will be gratefully received.
Edited By Windy on 24/01/2010 15:26:47
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