gritineye Posted January 22, 2012 Share Posted January 22, 2012 Have a look in that second hand tool store for one of these, this one does up to 1/2", the flare on your pipe looks a bit longer than usually made with these tools, Im sure you could easily modify it to suit though. Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
Old Bill Posted January 22, 2012 Share Posted January 22, 2012 Thanks chaps, that is great. I have never seen such a tool before but now I know what I am looking for. It comes of only ever working with rod or cable brakes! Steve :thumbsup: Quote Link to comment Share on other sites More sharing options...
Kufra Kiwi Posted January 22, 2012 Share Posted January 22, 2012 Photographed at Hood aerodrome air-show NZ on 21st January. I think the replica tank and original Thornycroft are owned by Sir Peter Jackson, who also owns most of the 21 (yes 21!!) WW1 planes on display. Quote Link to comment Share on other sites More sharing options...
Minesweeper Posted January 23, 2012 Share Posted January 23, 2012 [ATTACH]56000[/ATTACH] Have a look in that second hand tool store for one of these, this one does up to 1/2", the flare on your pipe looks a bit longer than usually made with these tools, Im sure you could easily modify it to suit though. Sure enough, David F. at the Tool Box in Colyton, East Devon - only just down the road from me has come up with the "goods"! Anybody living within range who does not know of this "emporium" should look in there for "stuff". He had one in stock for pipes from 1/8" to 3/4". Many thanks for the tip! Tony Quote Link to comment Share on other sites More sharing options...
gritineye Posted January 23, 2012 Share Posted January 23, 2012 (edited) You're welcome Tony, ain't HMVF a wonderful place... Here's a link, I'm sure they won't mind: http://www.thetoolbox.org.uk/about_the_toolbox.html Edited January 23, 2012 by gritineye added link Quote Link to comment Share on other sites More sharing options...
Asciidv Posted January 23, 2012 Share Posted January 23, 2012 I know that this question has nothing to do with the Thornycroft restoration :-(, but I do know that the kind of people who read this thread are ideal to answer my question about torque'ing down old cylinder head and big end nuts. I will be putting an old Leyland engine back together next weekend and was wondering what torque I should use on the head nuts and the big end nuts. They are both 1/2" BSF. If you look at all the charts available on the internet the suggested torque figure range from 30-120 ft lbs depending on the bolt grade. So the question being is 'What grade of bolt' did they use in the 1930's for this type of application? Barry. Quote Link to comment Share on other sites More sharing options...
Charawacky Posted January 24, 2012 Share Posted January 24, 2012 hello barry Your question is very relevant, I have been rebuilding my Crossley Tender engine, after re-whitemetaling of the mains I asked the chap who did it what torque the caps studs should be taken up to. His answer was 60 LBf on 1/2" whit bolts then the next split pin hole! just as he had done during line bore machining. Now whit is a very course thread and the next split pin hole can result in a much much higher torque,75 lbf! one of the studs necked and fortunately broke. At this point I reverted to the internet and the range 36 to 125 was given for 1/2" whit depending on material, in line with your comments. I realised the material must have been at the lower end of the range! I have now made a set of new studs in known material and torqued up to 60Lbf after machining the nut to achieve the correct torque and locate the spit pin. Although you are asking about big end bolts, some studs are used at both ends for bearing cap and block fixing so additional tension can be put on the bolt by over tightening the block nuts. Consider new bolts Tom Quote Link to comment Share on other sites More sharing options...
8_10 Brass Cleaner Posted January 24, 2012 Share Posted January 24, 2012 Whats all this about torquing up old tack about?. A 1/2 whit bolt, even in mild steel isnt going to give up on a main bearing. It may rattle loose but it isnt going to extend enough under load to cause problems, so why pre stress it?. If the material is on the weak side the issue is as you have found you will be near the ultimate tension on the material and it will 'give up' as you found. I've been brought up rebuilding Austin 7 engines and the traction engine, we tighten most things with a normal length spanner by hand, the rule is as tight as possible by hand with no extra leverage. We've never had a bolt or stud 'go' in service, things that may rattle loose get split pinned (or lock nuts). Certainly I woud agree with the advice for new big end bolts, but some of the torques quoted for old stuff is ludicrous. Did they have torque wrenches in 1916, and if they did, were they that common? Quote Link to comment Share on other sites More sharing options...
Grasshopper Posted January 25, 2012 Share Posted January 25, 2012 I would agree with hand tightening on vintage items (caliberated arm, Mk1) where no figure is given. Why pre-stress an old component? I recall the instruction for tightening the U-bolts on my old Matador were "Tighten the U-bolt nuts using a 4 ft spanner"! Quote Link to comment Share on other sites More sharing options...
fesm_ndt Posted January 25, 2012 Share Posted January 25, 2012 From my training years ago the length of the spanner is typically 10 times the width of the jaws, which in theory provides the correct torque unless ham fisted. One of the later military helecopters I used to work on shunned torque wrenches and relied mostly on the correct combination spanner. There was a technique to it and a really boring training video. Quote Link to comment Share on other sites More sharing options...
Asciidv Posted January 25, 2012 Share Posted January 25, 2012 Thanks, for the responses so far. In particular I found Tom's reply very much in line with my own thoughts although I hadn't considered the next logical step forwards and make my own studs in a material that I know the specification of - and hence the torque figure can be accurately specified. Setting torque just by 'feel' is risky I think, especially on cylinder head bolts. Even clamping pressure of the head gasket is important My straight six Leyland engine has always been susceptible to head gasket problems and I would always want to be as precise as possible with the setting of the head bolts. I have a realtively modern big V8 diesel in my transporter. The torque for the head bolts is 240 ft lbs. (Time for the 4 foot spanner....). I would defy anyone to achieve consitent torques (say within 10 percent) without a torque wrench at this level of torque. I do believe in the old ways, but I can guess when a little modern science is better! Barry. Quote Link to comment Share on other sites More sharing options...
8_10 Brass Cleaner Posted January 25, 2012 Share Posted January 25, 2012 Modern tack has gone away from torques, often using an initial quite mild torque with a specified angle to finish, which obviously gives a known extension, whearas a torque setting doesn't, as the torque is a function of the total 'friction' achieved. Use copper slip or somesuch and your bolt at a certain torque setting will be considerably tighter and will have more pre stress than an identical bolt done up dry. Another point to consider is that often WW1 engines use aluminium, it is worth considering the known thread engagement and shear area before wanging everything up tight as you dare. I've pulled no end of studs in aluminium just using normal spanners. Similarly all of the metal we are dealing with is old, and likely crystalline to some extent or other. When it comes to cylinder heads and gasket failiure, the long and short of it is that assuming both are correctly flat they will seal, if it isn't clearly big torques will help, but it is treating the symptom not the cause. Quote Link to comment Share on other sites More sharing options...
Great War truck Posted February 2, 2012 Author Share Posted February 2, 2012 We have not posted anything for a little while but work is still going on! Attention has now been turned to making new parts for the Valve Cap Retainer fittings - you may re-call that we had to destroy all the old ones to actually get them out of the block and the pictures of the bits of those are on Posting No. 140 dated the 29th December. We have started with the Locking Sleeve for the inlet valve cap. The photographs show them first of all in embryo form and then with one completed with the "hex" machined on the top. So three to be completed. These were machined from 60mm steel bar, turned down on the outside and threaded 2" by 11 tpi., Whit form. The centre was then drilled and bored out to 1 1/2" internal diameter. The last exercise in the machining process is to put a "hex" head on them, 1 5/8" AF You will notice that the "walls" of the hex are quite thin and I guess that it is no surprise that the originals had just about rusted away. When these four items are completed then the Dogs to hold them down will follow - these will be in cast iron. Quote Link to comment Share on other sites More sharing options...
Great War truck Posted February 4, 2012 Author Share Posted February 4, 2012 Half way there now! Quote Link to comment Share on other sites More sharing options...
Great War truck Posted February 6, 2012 Author Share Posted February 6, 2012 Steve has done a bit more to the pump by securing the impeller and pulley to the shaft. He has cut two keyways, fitted keys and then taper pins to prevent them from moving. The next part of the pump is making patterns for the inlet and the bearing carrier, for neither of which is it obvious how to do it. He is drawing them up at the moment to get a better understanding of them. Finally, he has finished off the valve plug locking locking bolts started by Father a week or two ago. Quote Link to comment Share on other sites More sharing options...
Great War truck Posted February 6, 2012 Author Share Posted February 6, 2012 The four Locking Sleeves for the Inlet Valve Caps have now been completed - the next job will be to make the four "Dogs" - or Valve Cap Bayonet Sleeves to hold them in place. This is quite a different arrangement from the Dennis and the FWD which had simple, one piece threaded plugs which screwed directly into the top of the cylinder to do the same job. I wonder why Thorny opted for this two piece arrangement? The "Dog" has an internal thread to take the Locking Sleeves - the "Dog" drops through a hole in the top of the cylinder and rotates through 90 degrees to secure it in position. The locking sleeve is then screwed down hard on top of the Valve cap to hold that in position. Quote Link to comment Share on other sites More sharing options...
Gordon_M Posted February 7, 2012 Share Posted February 7, 2012 Endless machining work - at least you have the facilities though. I certainly wouldn't make them out of ordinary cast iron as those lugs would just ping off at the first opportunity. Bit of forged steel bar would be the thing. Gordon Quote Link to comment Share on other sites More sharing options...
Old Bill Posted February 7, 2012 Share Posted February 7, 2012 Yes, I was concerned about that. The originals are definately cast iron, though, and I think I would rather break the tag on the sleeve than break out the top of the block! It was hard enough on my nerves cutting out the originals without damaging the blocks but we will go to steel if we have to. I think that if the cap is properly ground in, it shouldn't need much clamping force and I am sure it will soon carbon up anyway. Time will tell. We still have to get the pistons out and I am not looking forward to that much either. Steve Quote Link to comment Share on other sites More sharing options...
Cel Posted February 7, 2012 Share Posted February 7, 2012 We still have to get the pistons out and I am not looking forward to that much either.Steve The grease gun method usually works very well but I guess you have considered this already. Good luck with it! Marcel Quote Link to comment Share on other sites More sharing options...
Great War truck Posted February 11, 2012 Author Share Posted February 11, 2012 With the four Locking Sleeves for the Inlet Valve Caps made and out of the way, the next job is to make the "Dogs" also known as "Valve Cap Bayonet Sleeves" to hold them in place. These are made of cast iron. A 2" length of cast iron was was cut off from a 3" diameter cast iron bar, put in the lathe and the outside machining completed. A 3/4" diameter hole was then drilled into it. Ready for the boring tool, so that it could then be bored out ready for threading 2" x 11 to suit the Locking Sleeve. The threading was mainly completed with an internal screw-cutting tool and finished off with a Thread Chaser. The Locking Sleeves were tried in the freshly cut threads to make sure they fitted, and then the "Dog" was parted off from the holding piece in the lathe. We will get the other three to this same stage and then cut the superfluous parts of the flanges away, just leaving the bayonet parts which will hold them in position. Quote Link to comment Share on other sites More sharing options...
Old Bill Posted February 11, 2012 Share Posted February 11, 2012 The grease gun method usually works very well but I guess you have considered this already. Good luck with it! Marcel I have never had to consider this problem before and the grease gun method always appealed. However, it does mean that the block has to be sealed up which will be quite difficult. The valves are very corroded and will take some extracting in their own right. My plan of approach will be to have a look up the bores and polish them if there is any rust. Then I shall try to pull the pistons out. Some sort of jacking arrangement may be needed. After that heat may have to be used but I am very wary about that due to the danger of cracking the block. A steam box may be the answer, other wise it will be a gentle gas flame over a long period. I have seen a block inverted and the pistons filled with diesel before setting the diesel alight with the oxy-acetylene torch. This was spectacular and effective but takes a brave man to try! Watch this space. Steve Quote Link to comment Share on other sites More sharing options...
Horse Transport Posted February 12, 2012 Share Posted February 12, 2012 Tim ! I love you can you make me some water pumps for the Cart Water Tank ????? i cant do them they dont have grain or growth rings !!! and they would mess up my saw blades ! Quote Link to comment Share on other sites More sharing options...
onthecorner Posted February 13, 2012 Share Posted February 13, 2012 Fantastic work as per usual! Can I just ask why don't you use any coolant? Is it to do with the material, or the rotation speed, or just because you need to see what you're doing? Quote Link to comment Share on other sites More sharing options...
Minesweeper Posted February 13, 2012 Share Posted February 13, 2012 Fantastic work as per usual! Can I just ask why don't you use any coolant? Is it to do with the material, or the rotation speed, or just because you need to see what you're doing? Well, I am no professionally trained machinist and what I do is fiddle around and learn as I go! However, from what I know, no coolant is used when machining Cast Iron. With mild steel, then I use a cutting oil fed in from an old Fairy Liquid bottle - and take small cuts so that I can clearly see what is going on. I expect the professionals will throw their hands up into the air - but it seems to work for me! Tony Quote Link to comment Share on other sites More sharing options...
rog8811 Posted February 13, 2012 Share Posted February 13, 2012 no coolant is used when machining Cast Iron. Quite right, once you get under the skin of cast iron with a brave first cut its granular structure allows dry cutting. Superb work as usual, I always look out for your updates. Quote Link to comment Share on other sites More sharing options...
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