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Post by Deleted on Dec 12, 2017 16:48:21 GMT
Evening guys due to the serious issues that i'm having with my PC I'll have to keep this short but will give details that i can for this last weeks progress. As mentioned, I hadn't fully machined down the front face to size resulting in the bore being longer (deeper) than required, rather than cut the face further by hand I decided to include a spigot on the internal face of the end cover, the passageway locations are as per drawing so there's no change in the important parts of the cylinder and thus will have no adverse effect on it's other moving parts. As with Mervyn, I needed to make an extension piece to hold the (3mm) cutter and be able to reach the position for the front steamchest passage. The first picture shows this, using a suitable length of BMS, i drilled and tapped (counter bored to allow the cutter to be fully engaged) to take the 3mm cutter, ground a small flat on the cutter shank so that i could do it up tightly and also used a drop of loctite for extra security. Now this picture shows how much longer the bore is, it's supposed to be 2 3/4" and the front passage sits on the outer edge.. well the passage is where it's supposed to be but the bore continues for approx 1/8" and it's this area which will be taken up with the internal spigot. As stated this makes no difference to the cylinder and it's moving parts, it just means that the front cover will be 1/8" proud of where it's supposed to be, since there is plenty of room here and since it's not seen (not that anyone is likely to notice it anyway) and it doesn't impede with anything this IMHO is the best solution for me. Next I turned my attention to the front cover to see if there was enough material to include the planned 1/8" spigot, as it turns out there was plenty and ponders the question was the design changed at some point and the cover was supposed to have a spigot using a deeper bore? The drawing shows a flat cover, no locating spigot, When i machined the rear face i took it so it just took a whisker off the rough cast to leave a machined face, the rear passage is where it's supposed to be at the end of the bore (can been seen in the last picture) which would suggest the depth is correct and yet when I machined the face front lip (no figure on the drawing) I took it to what looked right for the drawing so a little surprised to have a bore deeper by 1/8"? add to this that the front cover casting measured 0.365 thick and if following the drawing (no spigot)it required a finished thickness of 0.156? so a casting with more than twice the required thickness from Reeves? hmm...unlikely... anyway with the spigot added I needed 0.281 which is covered by the casting easily and shown in this next picture. the 1/8" spigot is clearly seen and it's edge has been angled to match the chamfer in the bore. I will leave the small spigot until I have drilled the mounting holes around the circumference and machined the flat edge to clear the steamchest. next job was to make a start on machining the slide bar support top face, first i needed to scribe a line for where the metal needed to be machined too. I did this using a height gauge measuring 3/4" up from the centre of the bore. Plug in the bore is used as a visual aid for getting this right. Last picture for tonight has everything set up ready for machining the support to size, the width will be 5/8" as per drawing. Thursday i'll machine the support and then make a start on maching up a jig for holding the casting at 7 degrees for the boring out of the steamchest, i hope (pray) that I can get this PC working better than then as typing this latest update up has been a little stressful to say the least...i like to be able to see what I type as I type it, not wait a minute or two for it to appear...lol More soon .. if I haven't jumped on the PC that is... Pete
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Post by Deleted on Dec 12, 2017 17:02:04 GMT
hmm.. i feel like giving up these updates...lol so I did the write-up using 'Firefox' as it was the only way to log onto 'imgur', every thing appears fine on that browser but it's so slow on my PC that it's unusable and so i close down Firefox, open up edge so that i can copy/paste the update to FB and woe behold i can't see the damn images... I'm at a loss....lol
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Post by Deleted on Dec 12, 2017 17:12:25 GMT
how many of you guys can see the pictures?.. I can't....
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Post by steamer5 on Dec 12, 2017 17:23:07 GMT
Hi Pete, Yes can see the pictures.
Cheers Kerrin
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Post by Deleted on Dec 12, 2017 17:26:53 GMT
Thanks Kerrin.. yes i just spoke to my son... he said everyone else should be able to see the pictures, just that I can't as something on my PC is blocking the imgur URL.. damn PC...lol cheers mate.. Pete
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Post by chester on Dec 12, 2017 18:57:31 GMT
Hi Pete i can see them i am having to use Opera because firefox is throwing a wobbly.Keep up the good work.Graham
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don9f
Statesman
Les Warnett 9F, Martin Evans “Jinty”, a part built “Austin 7” and now a part built Springbok B1.
Posts: 960
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Post by don9f on Dec 12, 2017 21:03:44 GMT
Hi Pete, I can well imagine your frustration with the pc at the moment but appreciate your efforts to keep the updates coming....
Regards your “extra” 1/8 inch enigma, if you were to remove that 1/8 from the front face, wouldn’t your port break out into that face? Surely that wouldn’t be easily sealed in that reduced area!
As said earlier, I think you’ve chosen the right solution....but I was just wondering.
Cheers Don
ps don’t waste time replying to this if your pc is so slow it’s driving you nuts!
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Post by Deleted on Dec 12, 2017 21:25:46 GMT
Hi Pete, I can well imagine your frustration with the pc at the moment but appreciate your efforts to keep the updates coming.... Regards your “extra” 1/8 inch enigma, if you were to remove that 1/8 from the front face, wouldn’t your port break out into that face? Surely that wouldn’t be easily sealed in that reduced area! As said earlier, I think you’ve chosen the right solution....but I was just wondering. Cheers Don ps don’t waste time replying to this if your pc is so slow it’s driving you nuts! It's ok Don.. things are much faster when not using firefox which for now is the only way that I can access the 'Imgur' website, the drawback being that I can't see any images from Imgur with my normal browser.. or with other browsers ...just tried 'Opera' which Graham mentioned but that didn't work either... ... to answer your question Don, that is how it's drawn.. the port is right on the edge of the bore as is the back port right up against the rear face. It does beg the question if this was changed at a later date but not written...might explain why the cover casting is so thick? I don't know, still being very new to the 'live steam' side of things and this is my first ever cylinder to machine...It may just be coincidence that the casting is so thick, I'm happy with the way things are to go ahead.... thanks for the reply sir.. Pete
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Post by Deleted on Dec 18, 2017 18:38:41 GMT
evening chaps.. Now that the PC is running properly again I can continue with the updates, first picture to finish off where I left off, that being the machining of the slide bar bracket to a height of 3/4" from the centre of the bore below. Now one thing that is becoming more obvious as i work through this casting is that it was clearly a bad one but I'm managing to get around it. The cast itself has been cast offset, that explains the odd shape of the steamchest ends and now that i get to it the offest of the slidebar bracket. I of course centered on the bore below and machined out the bracket to it's 5/8" width, here you can see that there is more meat on one side than the other. Not so obvious in the picture but when using a square the bracket is slightly to one side of the bore? I have no idea what happened during the casting of this pattern, clearly something moved but as long as the steamchest bore machines without issue I think it will be ok, I wouldn't want to have to do all this again on a new casting. When looking at the outside cylinder castings there are none of these issues, they are like a Rolls Royce' to a mini...lol Perhaps i should have rejected the casting when received but to be honest having not seen one before and having not machined it I was a little blind to the problems, still onward and upwards.. Today I have made a start on the jig for holding the middle cylinder at 7 degree's, before machining the angle I first needed to transfer the mounting holes for it to fit on the cross slide as indeed I did the first jig block for machining the main bore. Picture shows the block having had it's face machined flat, (this block was an offcut from my son's work, it had been CNC'd on the lathe and thus had the marks associated with this, easy enough to remove) and the holes partly drilled using the other block as the template, once the angle is doen I'll finish the holes to size, I just needed a register for now. And so after a few hours of machining I had the block to the angle required.. I thought it prudent to finish today's effort to check what angle that the casting was showing before machining... no surprise then that it's out and by some margin at 1.2 degrees, if you recall there was no machining done to the bottom face, it was just flattened with W&D on a flat plate after removing a couple of high spot blobs of metal with a file so I know that the bottom hasn't been machined out of true. As you can see the digital gauge is showing a reading of 5.8 degrees. Just to be sure that all the parts are talking to each other I placed the casting on the machined jig to check it's reading too.. yep.. 1.2 degrees out.. So my next job will be once the holes are finished to set the casting up on the bed using the angled block and machine the top to be horizontal, I could possibly leave it but that would leave me with no datum to check the cylinder against the frames to be sitting fully horizontal in it's proper position, any error here would put the 7 degree incline out. While in this setup I'll also take care of the exhaust and blast passages which will need tapping too, I'll cover these details in the next update... thanks for looking in guys... Pete
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Post by Deleted on Dec 22, 2017 14:51:25 GMT
Good day all, this will be my last update before Xmas and perhaps the New Year although if allowed I will try to find time for a little more model engineering, it's good for the soul...honest. First up was to machine the top of the flanges so that they are exactly 7 degrees to the main bore, this will make life much easier for checking that the cylinder is at the correct angle when fitted, there's a fair bit of work involved before I can do this and will touch on it at the end of this update. Here we see my set-up for holding the cylinder, as with the mounting block for the main bore I have added a side support to ensure that the cylinder sits squarely on the 'x' axis for both mill and lathe and also I have added another support plate to the rear (right hand side of picture) to be able to lock the cylinder to the incline without any fear of it slipping. The angle gauge is used just to check that nothing has changed once bolted down. I forgot to add before that the angled block had slots machined in it for holding on the mill bed (the drilled holes for the bolts will be used for the lathe), the cylinder itself is held on the slide bracket at the rear and the front of the steamchest at the front, not the greatest of methods but it worked with no issue. After machining the flanges down to the correct angle (machined the webs too to match) I moved on to the steamchest steam inlet hole, after plotting the center and cross referencing with the dimensions on the drawing I center drilled the top of the inlet stub. Note the exhaust spigot has also been faced off. It was then on to tapping the 1/2"x32tpi thread into the steam inlet... So that's the inlet taken care off... Next up was the exhaust spigot, first job to machine the spigot to 7/8", I did this using the boring head which of course involved the tool bit being held inverted (I mean facing inwards) and the mill switched to run in reverse. then it was the turn of the bore itself opening it up as far as possible for hopefully better steaming, not forgetting that for this the tool needed to be turned around and the mill switched to forward. Now when cutting the thread on the saddle exhaust spigot It was easy to do as the saddle was held in the 4 jaw for machining so easier to get the die square to the spigot, for the cylinder I've gone a little 'heath robinson' and done it by feel and eye with the help of a bubble to ensure I didn't run out of square during turning. That's the inlet and exhaust passages taken care off... now with reference to my comments at the beginning, I'm going to spend some time getting the cylinder to sit in it's correct position before machining the steamchest, the reason being is that there's a lot of jiggling around to do here to get things right. There are a number of points to consider first, the bore must be at 7 degrees to the frames, the steamchest must line up with the 2:1 gear stay, there must be clearance for the saddle which when fitted becomes one unit with the cylinder. In the picture the cylinder is roughly in place, it needs to sit lower as in it's current position it's to high blocking the position where the saddle sits above it, the holes shown in the picture are the top 4 for the saddle and the lower 6 for the cylinder. Before I can lower the cylinder I need to remove a little from the rear flange corner to clear the vacuum stay howvere before doing this I need to ensure that the cyliner is in it's correct position distance wise from the saddle exhaust spigot which the drawing states (ref 2 1/2")...now for those who have been following the build for some years you may recall that I have moved the smokebox back 1/8" to match photo's of the prototype, this I believe all has something to do with the front bogie changing from swing link to side control but i won't go through all that again now. This is where we are at for close of play 2017, things are looking good if a little perplexing getting my head around all of the parts that need to add up for this to work, next update should have the final position of the middle cylinder sorted, the saddle drilled for the cylinder exhaust spigot, the steam inlet and also the bottom of the saddle to give clearance for the exhaust passage ways, lot's to do there... that's it for this year, I'd like to take this opportunity to wish everyone a very merry Xmas and assuming I find no time during the festive season for a further update a happy New Year. Merry Xmas Pete
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Post by tedsmith on Dec 23, 2017 9:27:39 GMT
happy xmas from ted in south Africa its' nice and warm here all the best for 2018
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Post by Jim on Dec 23, 2017 10:40:07 GMT
Same to you too Ted. It's warm here in Oz too.
Jim
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Post by Deleted on Jan 1, 2018 0:51:36 GMT
No it's not the first update for 2018....just me wishing everyone a Happy New Year and to say many thanks for all the help and kind words of encouragement in my build from so many people over the last 7 years. Thank you everyone...here's to the next 7 years.... Pete
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Post by Jim on Jan 1, 2018 2:39:19 GMT
Happy New Year to you too Pete. I look forward to Doncaster aka Flying Scotsman's continued progress towards that first steam up. Great to have your company over the last few years on our respective journeys.
Cheers
Jim.
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jma1009
Elder Statesman
Posts: 5,901
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Post by jma1009 on Jan 21, 2018 18:13:26 GMT
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Post by Deleted on Jan 21, 2018 22:18:11 GMT
Hi Julian
Very nice, more so as it looks like 'Blue Peter' may get back in steam one day, that's great news...
cheers
Pete
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Post by steamer5 on Jan 22, 2018 3:46:21 GMT
Hi Julian, Many thanks for posting that link! Would of been neat for a video of the process. Pete, A friend sent me this link, 2 hrs of enjoyment! You may have already seen it.....but if not then happy viewing! www.youtube.com/watch?v=Ny52YQ7QYcoCheers Kerrin
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Post by tedsmith on Feb 10, 2018 8:13:48 GMT
hi peter is every thing with you it's getting cooler here so we are back in the workshop regards ted
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Post by Deleted on Feb 13, 2018 8:39:24 GMT
Hi Ted
Sorry I missed your post, I've been a bit quite of late and not worked on 4472 since before xmas...I hope to get back on her soon..I have been sidetracked a little relaxing with the warship that I've started to build. Mind you I must be out of practice wielding a scalpel as I slipped and cut myself deeply between thumb and forefinger right across the web resulting in both being taped together to give the cut chance to heal. This has restricted my ability to do much just now.....a very silly thing to do...lol
regards
Pete
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Post by Jim on Feb 13, 2018 8:46:15 GMT
Great to see you back Pete.
Jim
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