uuu
Elder Statesman
your message here...
Posts: 2,816
Member is Online
|
Post by uuu on Jul 27, 2017 6:23:51 GMT
Quiet progress last night: We compared the rods with photographs from all angles, and tried to assess the correct thickness. Eventually we agreed a bit more should come off, so John put them back in the jig and carried on.
Meanwhile, I tried to answer a question that had been asked: would the rods fit? With the cylinders being non-standard, and the rods being different from drawings, and the wheel thickness, and the crank pins.... So I mounted one cylinder in its proper place, with the second one clamped to the back of the chassis, with a long bar in between, representing the line of the crank. We were able to see how things came together, and convince ourselves that there was room for the bushes, and a senible gap between the coupling rods and the crank.
At the end of the evening the thinner rods looked just right.
Wilf
|
|
johnthepump
Part of the e-furniture
Building 7 1/4"G Edward Thomas
Posts: 494
|
Post by johnthepump on Jul 27, 2017 22:04:52 GMT
Following up On Wilf's post, here is a Photo of the set up to check that there would be clearance between the coupling rods and the connecting rods. In the photo it can be seen that the second coupling rod is representing the connecting rod, resting on the 3/4" round bar spanning between the cylinder mounted in its working position and the one clamp to the back of the frames. The old crank pins were used just pushed in. Now we have proved that the rods will line up. I can now make a start on the connecting rods, firstly making a drawing from the collection of photos of No. 4 27.07.2017 by John The Pump, on Flickr John.
|
|
johnthepump
Part of the e-furniture
Building 7 1/4"G Edward Thomas
Posts: 494
|
Post by johnthepump on Aug 3, 2017 22:21:41 GMT
This Wednesday evening in the Pumphouse was quite busy, to start off I had ask Wilf to bring his test bar so I could check my 5" LeBlonde lathe. While machining 3 new axles for our Secretary's B1s tender I found that cross slide settings that I had used further up the bed didn't give the same diameter nearer the headstock. The cast iron legs of the lathe bolt onto the bed and movement on the floor can affect the accuracy, as it happens it is always our secretary who I have to ask not to lean against the machines. A little repositioning corrected the problem, it was suggested an engineers level should be used to check things out and get things sorted out , this is something that I have got but with an IPad to hand and using the spirit level app. not only do you get a visual indication in X and Y directions but also an numerical readout. The next job was to sort out the mounting plate that Wilf had a problem with mentioned in " What I have done today thread " a couple days ago, he had tried to CNC a 30mm hole in a stainless steel plate and the result the cutter rapidly blunted. There was one complete circular pass of this 4mm cutter, so I chain drilled in the in this recess to remove the centre and mounted the plate in a 4 jaw on the LeBlonde and bored it to the required size. 03.08.2017 by John The Pump, on Flickr Then it was time to make a start on the connecting rods for No.4. A steel bar 2.5" wide and 0.5" thick was cut off 16" long. from the drawing I had made the bar was marked out using a height gauge on the surface plate. A 2.5degree line was needed as the place to divide the plate to get the 2 rods out, so with a 5" sine bar and a set of slips the line was drawn. 03.08.2017 by John The Pump, on Flickr The bar was then clamped on the mill using the sine bar to set the angle. I then chain drilled along the line using a 4mm drill and 5mm steps. 03.08.2017 by John The Pump, on Flickr until the required length had been drilled. 03.08.2017 by John The Pump, on Flickr Then the holes were opened up to 5mm on the drilling machine and cuts made in from the edge to the line of holes and the a waste part cut from the ends, I now have the blanks and a lot of machining is to follow. 03.08.2017 by John The Pump, on Flickr John.
|
|
jem
Elder Statesman
Posts: 1,067
|
Post by jem on Aug 4, 2017 16:33:28 GMT
Hi There,
you mention "IPad to hand and using the spirit level app.this sounds most interesting, so I would be most grateful if you would elaborate on it, as I am sure that others would also.
I would have thought that the Ipad was not flat enough to use for instince so would like to know a bit more. I enjoy your thread, many interesting things, thanks
best wishes
Jem
|
|
|
Post by Deleted on Aug 5, 2017 11:34:04 GMT
Hi Jem
Many mobile phones have a built in inclinometer and accelerator sensor which clever apps use to measure anything from an angle to how many G's your car pulls and how quick your 0-60 is.....I have used my phone for these things many times, checking the level of something while high up in a cherry picker using just the phone is handy..you just need to calibrate it properly first on a known level to get an accurate reading, they are very accurate devices.
Pete
|
|
jem
Elder Statesman
Posts: 1,067
|
Post by jem on Aug 5, 2017 16:53:45 GMT
Hi Pete,
thanks very much for that info, I will have a look as It would be most useful.
best wishes
Jem
|
|
uuu
Elder Statesman
your message here...
Posts: 2,816
Member is Online
|
Post by uuu on Aug 5, 2017 18:37:36 GMT
As with digital "verniers", a phone or tablet is a lot easier to read than a bubble level. For checking a wall is plumb etc., I find my Android tablet is brilliant. I have an engineers level, with each line on the phial being .030" in 10 inches. That's just less than 0.2 degrees, so in the same ballpark as the tablet.
Wilf
|
|
johnthepump
Part of the e-furniture
Building 7 1/4"G Edward Thomas
Posts: 494
|
Post by johnthepump on Aug 6, 2017 10:28:57 GMT
Hi There, you mention "IPad to hand and using the spirit level app.this sounds most interesting, so I would be most grateful if you would elaborate on it, as I am sure that others would also. I would have thought that the Ipad was not flat enough to use for instince so would like to know a bit more. I enjoy your thread, many interesting things, thanks best wishes Jem Hi Jem, The lathe was checked using Wilf's test bar and found to 3.5 thou run out over the length of the bar, moving the tailstock legs forward on the concrete floor by about an inch to where it was before cured the problem. the front foot of the rear leg does have a piece of 1/8" packing under it to correct for the floor and things are fine until one or other of my visitors takes to leaning on or against machines, it is not that there aren't 2 stools for them to sit on if they are tired. As far as the IPad goes with it laid across the bed of my LeBlond resting on a sheet of A4 paper to keep it clean, the head stock and tailstock end now read 0.0 deg. across the ways and 2.1 deg. along the ways. By placing a piece of 4 thou. packing on the back way the reading changes by 0.1deg. WP_20170806_10_33_22_Pro by John The Pump, on Flickr I hope this helps and it would be interesting to hear others views on the subject. I will ask Wilf to bring his Engineers level with him next time he comes and we can the makes some comparisons. Regards John.
|
|
jem
Elder Statesman
Posts: 1,067
|
Post by jem on Aug 7, 2017 17:31:35 GMT
Thank you very much for the further info on using the Ipad fpore leveling John, this all sounds most interesting.
Wilf, you mention the Android also has an AP, please could you give me its name, as I have an Andriod tablet, and would like to download the ap.
best wishes
Jem
|
|
uuu
Elder Statesman
your message here...
Posts: 2,816
Member is Online
|
Post by uuu on Aug 8, 2017 5:14:25 GMT
I use one called "Clinometer". It's not currently loaded, since I did a wipe clean an reload on this machine. I suspect there's a choice on the app store.
Wilf
|
|
johnthepump
Part of the e-furniture
Building 7 1/4"G Edward Thomas
Posts: 494
|
Post by johnthepump on Aug 11, 2017 10:22:26 GMT
Wednesday evening started off talking about the DH Mosquitos, my sister had visited the de HAVILLAND aircraft museum at Hatfield on her way with her partner to go to this years game fair at Hatfield house and had brought back some leaflets and sent a photo, we started to discuss organising a day trip. I had lent a book last week to one of my Wednesday regulars, called Mosquito Tempest and Typhoon and he had found this very interesting and thought the trip would be well worth it. My father had been sent to de Havilland's as an AID inspector during the war after training at Bristol and Reading. Mosquito by John The Pump, on Flickr Eventually we got back on to model engineering and made a start on machining the connecting rods for No.4, starting by boring the crankpin hole. 09.08.2017 by John The Pump, on Flickr On Tuesday evening which is when I try to do bits for others and club projects, I was making parts for twin axle pumps for the clubs Modified Ajax 4-4-0, I will put some pics up when I have got a more done. John.
|
|
|
Post by Deleted on Aug 11, 2017 15:08:17 GMT
The mosquito museum is well worth a visit, it's only 20 mins from me so naturally, I have visited...One of my late Grandfathers was ground crew to these beautiful aircraft, the other a tail gunner in Lancasters with over 3 tours notched up throughout the entire duration of the war, starting in Blenheims, then Wellingtons, and finishing in the mighty Lancaster.
Pete
|
|
|
Post by Jim on Aug 12, 2017 0:32:30 GMT
Three tours with Bomber Command is an incredible achievement. The air crews were incredibly stoic, going out night after night knowing their chances of returning were slim indeed. Thanks Pete.
Jim
|
|
|
Post by Deleted on Aug 12, 2017 9:13:03 GMT
Thanks, Jim....in some respects he was an old man, certainly the oldest in his crew at34 at the outbreak of war....most crew were very young...When I find the time I'll do more research into his service record...I had a lovely letter from the then commander of 550 sq giving me details of all of the missions that he did during his tour there...some harrowing accounts...one of which stated his aircraft was forced into a corkscrew trying to evade the numerous search lights and AA fire over Berlin....that must have been terrifying, to say the least....they were under heavy fire for 4 minutes until the pilot managed to escape the lights.
Pete
|
|
|
Post by d304 on Aug 12, 2017 13:09:32 GMT
Hi John and Jim
At one stage Salisbury Hall was tha home to none other than Sir Nigel Gresley. Apparently he wanted to breed wild ducks, particularly Mallard ducks. In 1939 the de Havilland Mosquito design team moved in headed by R E Bishop. One story about the Mosquito design was the shape of the fuselage was based on a mounted fish on the door of the toilet. Makes you wonder did Eric Bishop look at the Gresley A4's streamlining. The A4 running boards were based on the airfoil shape of the R101 airship of 1930.
Regards
David
|
|
|
Post by jordanleeds on Aug 21, 2017 6:42:04 GMT
John great to see some fantastic progress, my Edward Thomas has been on hold of late due to a much larger project taking my time, couple of queries if I may though, The longitudinal frame angles on the drawing are shown as 1" angle but no other dimension is given what have you used and my concern is that the top of the valve chest may be a potential clash with this. Have you notched this around this area? .
Just spent an evening between nursing a 2 year old who wouldn't sleep studying the drawings and drawing up motion for water jet cutting (it may be cheating but time is a finite material around my parts!)
Keep the superb work up!
|
|
johnthepump
Part of the e-furniture
Building 7 1/4"G Edward Thomas
Posts: 494
|
Post by johnthepump on Aug 21, 2017 10:19:37 GMT
John great to see some fantastic progress, my Edward Thomas has been on hold of late due to a much larger project taking my time, couple of queries if I may though, The longitudinal frame angles on the drawing are shown as 1" angle but no other dimension is given what have you used and my concern is that the top of the valve chest may be a potential clash with this. Have you notched this around this area? . Just spent an evening between nursing a 2 year old who wouldn't sleep studying the drawings and drawing up motion for water jet cutting (it may be cheating but time is a finite material around my parts!) Keep the superb work up! Hi Jordan, I had been meaning to get in touch. But to answer your question first, the longitudinal angle I used was 25mm in place of inch it was cut down to 5/8" as per the drawing T34/2 for the side that is riveted to the frames. I do not see any problem with the 1 inch side clashing with the valve chest. Looking at drawing T34/4, the edge valve chest is 1.3125" from the cylinder mounting face and then the cylinder is mounted on a back plate 0.6875" this puts the edge of the valve chest 2" from the frames. The point I wanted to warn you about is on the cylinder back plate to frame mounting holes, on drawing T34/3 the 3 holes are spaced 1.125" apart. BUT on drawing T34/4 the cylinder back plate to frame mounting holes are are spaced 1.25"apart. Before you ask which holes I settled on, my cylinders are totally different and do not require the backing plate, the error only came to light when making a jig plate to re-drill my frames for direct mounting holes. I hope this information helps, its nice to know that someone else is building No.4 Regards John.
|
|
johnthepump
Part of the e-furniture
Building 7 1/4"G Edward Thomas
Posts: 494
|
Post by johnthepump on Aug 31, 2017 9:38:58 GMT
Wednesday evening saw further progress made on No.4's connecting rods with the shape become clearer more than when we started as the blanks looked like 2 rather larger taper wedges. 30.08.2017 by John The Pump, on Flickr A ripper cutter was used to great effect and then the final couple of passes were taken with an ordinary end mill. In the photo below some of the holding clamps have been removed to give a better view. 30.08.2017 by John The Pump, on Flickr There is still a lot of work left to do on these rods and as always other things seem to take a large part of my time. John.
|
|
|
Post by Deleted on Aug 31, 2017 10:49:20 GMT
I like that idea of doing both together John, when I get to these I think I'll investigate whether my gear is capable of the same....great work sir..
Pete
|
|
johnthepump
Part of the e-furniture
Building 7 1/4"G Edward Thomas
Posts: 494
|
Post by johnthepump on Oct 1, 2017 8:50:33 GMT
Early in September We were in Ireland for 6 days holiday staying in Dublin and yes we did the Guinness storehouse tour. on the morning of Friday the 8th my wife decided that as she wasn't feeling A1 that she would stop in the hotel. So I ventured out and thought I would take a ride on the trams that ran past the hotel we were staying in. For 7 euros I was able to buy a 1 day all area ticket, I had noticed that one of the destinations was called the point, so that where I decided to try first. On my arrival all I could hear was the revving of lots of car engines, I had by chance stumbled on the start of the 2017 Ireland Cannonball run, 5 mins to the start I saw flagged up there were 190 cars entered I was told. Cannonball run Ireland 2017 by John The Pump, on Flickr Cannonball run Ireland 2017 by John The Pump, on Flickr
|
|