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: 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
|Thread: General club questions|
I see Pickering Experimental Engineering & Model Society was not mentioned.
Our members are into many branches of model engineering including the following Traction engines, I.C. engines, Boats, Locomotives,Clocks, Tools, Cars, Motorcycles, Hot Air engines, Stationary engines and the full size ones.
Its not a massive club but friendly and members are interested in all engineering projects.
I must thank the Editor and All the contributors for an excellent magazine. I have just received No.4367. The mixture of articles is very good, as an amateur it is pleasant to see scratch built static scale models as well as fully working ones. The I/C Topics I found fascinating and the various steam powered model builds equally so. Addicted as I am to speed related machines both model and full-size I wonder if someone would write an article on performance tuning of model I/C racing engines. As there are some motorcycle enthusiasts amongst our model engineers one of my locals will be attempting to break the World Land Speed Record on two wheels hopefully in 2010 with a streamliner powered by a V 8 that has Hyabusa top ends, The record to break is 367.382mph set a few months ago by Denis Manning’s streamliner with a homebrewed V4. Thanks David for a great magazine and Website.
Edited By Windy on 13/12/2009 19:12:12
|Thread: Material for piston/cylinder.|
Hi Jens, I run a high performance model single cylinder steam engine 15,000rpm free running, 10,500rpm under load and the piston and cylinder are cast iron. The only problem is corrosion but if well lubricated that should be ok.
|Thread: Leaky Safety Valves.|
Hi Meyrick, regards seating on valves, a method suggested in the flash steamers bible Experimental Flash Steam by J H Benson and A A Rayman on page 101 solder a ball on a piece of tubing of slightly smaller diameter. This is rotated in a drill chuck and the valve seat burnished. No abrasive required less than a minute of this treatment will do the trick. On my flash steamer all the pump valves are stainless steel and the balls have to be non magnetic as the magnetic type balls dont seem to like hot water and steam and the lovely smooth finish disappears. Back to the book I see John Benson and his Son at some of the regattas I compete at a most charming man and allways a pleasure to meet.
Regards Viton products in vehicle fires when I was in the motor body repair trade we had warnings about the hazards. Look at the HSE site now about the risks it makes interesting reading.
|Thread: Dynamic balancing|
Hi, I would like to thank the forum for all the knowledge that is being posted and the entertaining useful hits and tips by two of the regular contributors, keep up the good work. I would like to know if there is anybody in the Yorkshire region that does dynamic balancing for the model engineer. I did think of making a balancer but its not worth it for a one off. The turbo charger repair lads have machines that go up to 250,000rpm but are set up for turbo chargers only. The maximum rpm that I am thinking of is 80,000. One engineering forum website has a very basic dynamic balancer but only up to 8,000rpm, any suggestions gratefully received.
|Thread: Flash Steam Hydroplanes|
Hi, pleased that it was interesting if you go on www.onthewire.co.uk a great site for venues, dates, history and present day tethered car and hydroplane activities.
I am trying show tethered hydroplane racing is still alive and kicking as there is not much about it in the magazines.
This is my procedure for a flash steam hydro run.
Warm up on the bench, check water and fuel, fit starter cord, make sure bridle wires are clear, wade out and fasten to attachment wire, fasten bungee to front sponson hook, bungee and hydro supported by helper while I pressurise burner, when hot enough close steam release valve, pump water to generator till you feel pressure then pull starter cord.
When engine starts helper steps back and I load the engine with the propeller in the water, as the power builds you give a push to the boat and pray.
Speed builds up on every lap, when I think it’s fast enough my hand goes up for 5 100 metre timed laps.
It was going very fast and did over 107 mph but if timed 2 laps earlier 113 mph plus would have been achieved.
Checking video of run with stopwatch 2 laps before timed laps verified 113mph speed. The flash steam record is 120+mph held by Bob Kirtley. See him go on a fast run and my hydro seems slow.
Timing is done by 3 stopwatches and the average taken.
H/S is an issue we take very seriously e.g. all bridle wires can only be bought from one source and are tested, there are rules for the various classes.
Hope this rekindles interest in a very old side of Model Power Boat Racing.
My round the pole flash steam hydroplane on its last run of 2009
|Thread: Professor Chaddock|
Thank you Weary, I have searched that sight and now have the information that I require.
This forum is exellent ask for help and a fellow enthusiast will give you guidence.
Hello all, one of my P.E.E.M.S. club members mentioned that Professor Chaddock had wrote some articles in M.E. on making turbine blades using a homemade copying attachment.
Would anybody be able to tell me the M.E. volume number that the article was printed in or any other articles relating to turbines he wrote.
|Thread: MYFORD 254S Lathe|
Hello Andre, sorry I can't help with the wiring but your comment about company web-sites hit a nerve. After many hours trawling through the SKF bearing web-site cataloque I found 4 precision hybrid bearings suitable for my project. The SKF distributor for my area could not get any useful response from them and I e-mailed SKF head office, guess no reply. Eventually found some on the GTBA web-site. It seems unless you are spending thousands of pounds the large companies dont want your custom. Hope you get your wiring sorted.
|Thread: Visiting UK|
I see York has been mentioned apart from the NRM there is the aircraft museum at Elvington on an airfield where numerous World and National speed records have been broken.
|Thread: Books for beginers|
Hello Alan, we all have to start at the beginning at whatever we do, may I suggest as a newcomer to Model engineerig join a club if you haven't already.
Some clubs have a libary or maybe somebody who could advise you on lathe work.
As an amateur engineer myself you will amaze your self at what you can create out of various materials.
It might not be a show stopper but its what you made.
As an elderly friend once said to me if you think you can not do something join the try company (health and safety issues to be considered).
All the best for joining the ranks of the metal munchers.
Edited By Windy on 13/10/2009 22:12:10
|Thread: valve springs|
Hello, you will probably have sorted your springs by now but another web site that has numerous software programs for springs and many other engineering things is the Steam Automobile Club of America.
Go to resources and links then software for people who build things by Marv Klotz.
Apart from springs, programs for cams, valve timing etc.
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