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Member postings for Ian Lee

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

Thread: Turning a tapered carburator needle
20/11/2018 21:58:22

Just an update, we have tried the needles and they work, however it is back to the drawing board as although the car actually runs it needs some choke so running a bit lean, I am now making some more needles with a different and slimmer taper, am trying to steps every 1/8th inch so will see if I can manage it on my Clarkson tool grinder.

03/11/2018 20:19:42
Georgeineer, turns out that the original needles somewhere along the way got lost, The carbs for this Bentley were basically a one off and onle ever made for this car, the carbs were assembled from a variety of SU bits, the main jets were made by an engine tuner as were the needles, this is why it's not easy to get the thing to run. Thevidea is I make this pair of needles and hopefully it will run up through the rev range, then believe it or not John is going to one of those tune up spark plugs so we can see it burning.
02/11/2018 23:17:27

To everyone who commented thank you, I have managed to make these needles, I ended up removing the complete milling head from a small Clarkes milling machine I bought years ago from machine mart, I mounted it on my tool and cutter grinder, I then put the nickle silver rod in an ER32 collet and spun it at 2000 rpm against a 6 inch cup wheel, it worked a treat. I have just to put the circlip grove in them and we will try them out later this week, I will give an update about when they are intalled.

17/10/2018 23:06:10

Jason , am going by the measurement I have been given by John, the guy that wants them. Thaiguzzi, I think John may have spoken to Amal as I told him they still make carbs, if he has not spoken to them I will tell him. I must admit that I want to have a go at making them, some of the things I have already made for John are bonnet mounted pennant holders for two of the Queens cars in her collection, recently I made a worm and wheel for a windscreen wiper gearbox on a 1938 Vanden Plas bodied Bentley and reconditioned a 1927 Rolls crankshaft vibration damper which had been stood for nearley 60 years. I do like a bit of a challenge, I have found out that the numbering on the drawings for the needle seems to relate to the fuel mixture rate at different throttle openings rather that different or variating tapers. I do however like to find or aquire advice from people, The response I have had with helpful comments, ideas and advice from my request is really appreciated.


16/10/2018 23:37:41
As far as I know my friend has a copy of WinSU and it can't give an answer due to the fact that the car weighs nearly 2.5 tonnes and has a non standard supercharger.
16/10/2018 23:31:23
The guy I am making these for is one of the foremost Rolls and Bentley vintage car restorers and he can't find any info about these carbs as they were made only for W O Bentley and no one else. The engine is a Rolls Royce straight 6. The car was built between 1928 to 1930 with one the prototype and another copy. There are a few copies about on genuine Rolls Royce chassis and engines but they were built much later.
16/10/2018 23:22:28
There is no information at all available for these carbs, there is no serial number on them and no archived info about them.
16/10/2018 23:20:14
Holding the needle is no problem as I have a Myford collet set and an Er32 and Er20 set. The taper is even and not stepped, the originals were for some reason broken. The actual carbs are basically one offs, they are massive compared with Bentleys standard supercharched SUs. I thank you all for your suggestions. I was thinking of grinding them, I do have a high speed spindle which I could mount on my vertical slide, what I am trying to avoid is making the taper concave over its length. The tapered end of the needle has a point on the end so I will have a go at making a tailstock mounted brass centre support. I may try all of your suggested ideas before I make the actual needles. The actual car was made to run flat out everywhere as it was purely designed for racing the French Blue Train over the Alps.
16/10/2018 21:47:36
Strictly speeaking this is not a model engineering componant. I have been asked to make 2 carburator needles for an extremely rare supercharged Bentley. The pair of needles need to be 3 inch long with a taper length of 2.5in. The larger diameter is .125in and the smaller end is .100in. this gives a taper of 1deg 25" 50secs which is half the included angle. I will have to turn them with the compound slide as I do not have a taper turning attachment. The material will be nickel rod.

Has anyone any experience of make needles for carb throttle slides and has anyong got any advice or helpful comments. This particular Bentley is a Bentley Blue Train, the SU carbs on the supercharger were custom made for W O Bentley and only about 8 of these carbs were ever made.

Edited By Ian Lee on 16/10/2018 21:50:26

Thread: .225 dia x 40 tpi die
07/01/2017 21:53:42

When I worked in the engineering industry I used a lot of tallow, it was particularly good for threading, slotting and shapers. its just stank a bit, we tried all of the early modern tapping lubricants but they were not quite as good as tallow.

06/01/2017 22:52:27

Thank you all for your comments and advice, I actually took John Stevensons advice and linished to outside of the die, I went out and bought a Clarke Electric file from Machine Mart. It worked a treat, I turned a boss and threaded it to 7/32 x 40 tpi, I ran the die up to the shoulder, undid the die holder and left the die on the boss, put my lathe to 65rpm then used the new electric file to remove about 7 thou off of the diameter, worked a treat. I found that the grub screws in my die holder had a slight taper up to a flat end which was no good for opening the die up, I went to our local fastner supplier (BBN Fastnet) and bought some cone end grub screws, worked a treat at opening up the die.

05/01/2017 16:02:55
Jason, yes I could do with an old die set but finding one with 40 Tpi is difficult.
05/01/2017 16:00:21
Clive, It is the multiple aperture sights I am replacing with 5 seperate sights. The rifle is my friends lee Enfield Mk1. The thread is definately .225. I have checked it against a similar sight. The reason for seperate sights is that the larger multiple sight fouls the top of an early telescopic sight mount. The problem is the fact that 7/32 thread is too loose and is not repeatably accurate. My freind is quite fastidious as he is a very good shot (65th out of 1500 at the last Bisley event)
04/01/2017 23:32:25

Thanks for the info, 7/32 x 40 whitworth thread form is now ME thread, and I thought it may be the case that over the years of manufacture the diameter altered, I only need a 7/32 die to open about 5 or 6 thou as 7/32 is .2187 dia.

04/01/2017 22:15:03

Can anyone help me, I am restoring and re making some aperture rifle sights for an old (1895) Enfield rifle, The original sight was made by Parker Hale, The thread I need to cut is .225 diameter x 40 TPI. The threaded spigot is 1/4" long, I have tried to open up a 7/32 ME die and close up a 1/4 ME dia but can't get a correct fit in the sight mounting.

I wondered of anyone has come across this problem. I could screw cut it but there is not much room, as I am making a number of these with different sized apertures it would be quicker and easier if I had a die or a 40tpi thread chaser.

Edited By Ian Lee on 04/01/2017 22:21:15

Thread: Scale narrow gauge locomotive
27/10/2016 22:53:54

It will be electrically driven as the boiler cost is to expensive even if I make it myself, I am in a lucky position in that one of my close freinds is a pattern maker and another friend has a non ferrous foundry so I can getting castings made quite easily.

27/10/2016 22:46:35

Thank you Geoff

I was having a senior moment when trying to work out the scale, you have confirmed what I thought, I got 1/4.8 full size. I started drawing it from my plans then realised just how big it will be, thats when the doubt crept in. Its a 262-262 wheel layout, It works out that each set of frames will be 37 inches long, overall lenght will be about 11ft. Fortunately I do have room to build it and the machining capability although it is too long to fit on our club turntable.

27/10/2016 21:22:41

I am just planning the building of a narrow gauge Beyer Peacock Garratt, I have a full set of original drawings, The full size loco gauge is 2ft or 610mm, I want to scale the size to run on 5inch gauge, can anyone tell me what the scale should be, is it 1.0625 per inch ?

The drawings are for a South African Railways 2ft gauge Garratt.

Thread: Clarke / Warco Major Milling machine drawbar self ejector
08/10/2016 21:54:31

Can anyone point me towards information / drawings for a self ejector for the drawbar on a Clarke / Warco Major milling machine please

Thread: Gas bottles
13/12/2015 20:11:43

I have the German set which I think use the same threads, left hand for the oxy, right hand for the fuel gas. Oxy is a bit expensive at around 25 to 30 quid but the fuel gas (Mapp gas) is not very expensive. I get my gas from a variety of local suppliers, BOC depot in Bradford is only 1/4 mile from me away as is Energas, I have welded thin steel with this set and silver soldered brass, copper and steel. Some Machine Mart shops sell the bottles.There are also 3 engineers suppliers near to me also selling the cylinders.

Its worth checking any engineers suppliers near to you.

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