Here is a list of all the postings Paul Kemp has made in our forums. Click on a thread name to jump to the thread.
|Thread: traction engine pump|
You say the pump works off the engine when dunked in a shallow container. That implies the suction fitting on the pump body is direct in the water? When operating the pump like that does it develop any pressure on the outlet or are you just observing a little water being discharged? If you put your finger over the outlet when testing off the engine you can see if it is developing any pressure. You can test the delivery valve by connecting an air line (carefully) to the outlet. If the valve is good there will be no movement of the ram. You can test the suction valve by blocking or plugging the outlet, you should be able to pull the ram out on the suction stroke but not push it back in on the delivery stroke. If you can push the ram in you need to check if either the ram seal is leaking or if it is returning past the suction valve ie the suction valve is leaking. That will confirm the pump is good. Last thought is the pump of a type that has an integral bypass valve fitted in the body casting. If so as Jason said is the valve in the correct position? Picture of the pump might help. Good luck.
|Thread: Class 22 Diesel (next project)|
Personally I think you are over thinking the situation between pulley and bearing. Firstly the relative rotational speeds are pretty low as are the loadings. If the shaft is to be a soft (say mild steel) material then using hardened washers is likely to have them cut a groove in the shaft over time! Oilite is a bearing material and no reason to suppose that in this 'thrust' application it will be any less efficient than in the normal radial condition. Many thrust bearings are plain bronze with oil lubrication, oilite is a similar but 'self lubricating' material. Your PTFE washer is probably the kindest solution to shaft, bearing and pulley if you really want to control the axial location of the assembly. Lastly I doubt the loco will travel the distance of London to Edinburgh so whatever you do is unlikely to wear catastrophically.
is the TE on the back burner now?
|Thread: Rover V8 drilling valve guides|
I would assume it's to preserve the fit. Every time you press something out the hole gets a teeny bit bigger. Drilling them out first reduces the bulk of material and relaxes the strength of the fit hence reducing the growth of the hole and preserving the original tolerance.
|Thread: boiler parts|
Through a hole and pipe extension off the side, not yet drilled and fitted! Looks like it was left once the turning was completed and never finished!
Difficult to be sure with the size of the picture but it looks like it should be a captive blow down valve. Ball goes in the shroud at the end of the spindle which gets forced onto the seat in the body when the spindle is tightened. Back nut is to stop you screwing it all the way out!
|Thread: Motorcycle 'blipping'...|
Try driving London bound on the M2 / A2 in the morning and the opposite way in the evening! I unfortunately have to do this fairly regularly and having ridden bikes myself I still have palpitations watching the antics, get on centre white line between lanes, open throttle and try to weave between anything that may be in your path - it's worse on the multi lane sections if you are in a car at 60 (you can rarely get to 70 and more often 15 is optimistic!) but at 60 you can have the pleasure of being both undertaken and overtaken by bikes on either side between the adjacent cars - not even waiting for a gap! I have had my mirror clouted twice in the last fortnight and saw one come to grief. Maybe things are different in your neck of the woods! I rode bikes for many years and did a few track days but the way bikers behave now scares me!
|Thread: Part built Allchin 1.5 inch|
Afraid I don't know the detail of the Alchin diff as have never built one but when making the diff on my LS I left the centre boss of the diff housing (both sides) over length from the figure quoted on the drawing. I then set it up in the lathe first one way and then the other and gently faced it back to get a nice engagement with a bit of clearance / backlash on both crown wheels to the pinions. Worth mentioning all gears in the diff on my 6" LS are cast gears (as many full size engines were) so they are not as precise as machined gears!
As I am guessing on the Alchin I would say you are on the right track with shims. Ideally you want a little bit of backlash in the diff for smooth running.
"small amount" of play will be fine. In practice the diff gears only really rotate when turning corners and then only a tooth or two at a time or depending on the set up if winching where they may turn proper. If you look at any full size engine gears, your small amount would translate to a brand new running fit! If you think about the age of these machines many of them are well past their sell by date in terms of gear wear but they still run just find albeit a little on the noisy side!
|Thread: Hostaform, Nylon or Steel For Mini Mill Gear?|
If you look at Arc Eurotrade web site you might just find a picture of a mill very similar to yours and if you look at the parts list you may well find they have exactly what you need sat on their shelf which for less time and probably less money they could send you, over you making your own.
|Thread: Omnimill 00|
You might want to consider fitting a bigger hand wheel to the knee, if you have a job with a lot of vertical movement you will find the small wheel hard work. The small wheel should fit on the other end of the table to give you another option for table traverse. The machines were only supplied with one table hand wheel as standard from new.
|Thread: Steam Engine Number One|
My baby mill is exactly the same as yours and I have suffered several failures too! First time round I split the motor gear so fitted a new one - key was slack so I filed up a new stepped key that was a good neat fit. Second failure was the gear fork breaking completely and similar damage to the gears. Replaced the lot, third time it spread like yours and of course broke when I went to straighten it - so I welded it back together! That drove all the oil out of the bushes so I soaked it for a few days, made a new longer key that spans the gears fully and off we went again. So far, it's still running! My impression is the radiused end on the short key acts like a wedge in the nylon and jacks the gears apart, bending the fork. My new key is full width of the gears and square ended so eliminates the possibility of the wedge effect. Try making your own key with the new gears rather than using the std one, I feel you will get on better! Only needs files and patience!
|Thread: Injector Testing|
Ok. Afraid I am not familiar with the device! Any chance it is configured so the gauge reads a differential preassure? That could tie in with the other contribution of often reading "considerably higher than boiler pressure" ?
Have you checked the pressure gauge? They have been known to be wrong!
|Thread: stamford show vandals|
I think to use the example of Mr Fraser to support the argument that physical punishment does not work is stretching the point a little. Sadly there will always be examples like that and I very much doubt given he was certified insane several times that the soft touch would have been any more successful! Whatever the arguments for or against hanging and similar disfiguring punishments (and I am not advocating either way) at least hanging guarantees 100% there is no chance of a re-offence by the recipient! How many cases have their been in recent history of offenders being released, supposedly assessed by professionals as rehabilitated and posing no further risk to society that have gone on the re-offend with devastating consequences for innocent individuals going about their daily business who have just been in the wrong place at the wrong time!
Using statistical data as sole evidence of the success or failure of any policy is also flawed if used in isolation who said there are lies, damn lies and statistics? Pure numerical evidence can be manipulated to convince something is so when in fact taken in conjunction with other evidence the picture is different.
If there was a true answer to the problem properly implemented there would be no problem! Fact is as highlighted by others there are many variables that contribute such as cultural belief, ethics, morals and example. As I think I said a good few post back if society instilled successfully in its peers a proper sense of right and wrong and moral conduct then the judicial system would only be needed to deal with the minority extremes like Mr Fraser and his 89 year old ASBO holding mate and in their case segregation or eradication from the masses would be the only sure fire way of preventing further mischief!
As also said by others the deterrent of respect for the law coupled with a high chance of being caught is fast disappearing in this country so expect plenty more examples like this in the future!
|Thread: Loco hand pump casting from Reeves|
Dave, that's a good wheeze, nice bit of thinking there, not keen on the idea though but I am sure you have cracked it, especially as we can now see the full note which suggests you are right. I am intrigued the side view shows a 3/4" bore, there is no apparent significant step shown in the bore of the body but the end view shows a bore size of 1/2"?
|Thread: 5 inch 0-4-0 Shunter|
Oh Ron! Category A SPAD, suspended immediately from footplate duties and relegated to shed cleaner!!
Seriously, glad it all went well and all enjoyed themselves, that's what it's all about at the end of the day, makes the solitary hours in the shed and the head scratching trying to solve the design and machining problems all worth while.
|Thread: stamford show vandals|
But, the "Hanging is too good for them" side of the debate need to take stock and think well on such pronouncements.
Well I guess I am guilty of tending towards the above group. My frustration really originates from the 'modern' expectation that the criminal justice system is veiwed by the more liberally minded as a substitute for the inability of society to instill proper morals within itself. I am afraid my view is the penal system should provide deterrent and punishment for those that refuse to conform to the majority accepted standard of respect for others and the basic premis of right and wrong. The expectation of that function being performed by the penal system will not reduce offences. It's locking the door after the horse has gone! I have a major problem with human rights for offenders, they make a choice be it conscious or unconscious to commit these acts, when they do they should accept the normal priveledges associated with liberty and respect of their rights are removed. In carrying out the act these morons did they had no respect for the efforts or time expended by the owners of the property they destroyed. No amount of money can replace that time and effort and the psychological effect on the victims will be immense. The expectation that a short or soft response by the court attached to some love and forgiveness will turn these people around is naive. Society itself as Neil suggests needs to look in the mirror and govern itself to produce moral upstanding citizens. The courts should deliver retribution to those that fail to respond. The very way society as whole is being manoeuvred by marketing and commercialism to create the desire to have the latest fashions in clothes and gadgets is not helping!
I refuse to accept that these poor misguided individuals have not experienced at any time in ther short lives any positive examples of right and wrong, I also very much doubt they have any shred of remorse and if reading any comment on line regarding this incident they will probably be revelling in the 'fame'. They did the crime, they should be sanctioned, not rewarded.
|Thread: Loco hand pump casting from Reeves|
Well the note on the drawing has me confused. Make 1st pump to drawing, make 2nd less - looks like anchor links? Obscured by the rule. That sort of suggests the two pumps bolt together on the flange? In which case you have two opposed rams, how does that work with one handle? Drawing in isolation makes no sense to me but as per usual in model "drawings" they are hardly really drawings! If you took them to any half decent machine shop they would refuse to make it without proper detail and tolerances.
|Thread: Which thread for T nuts|
If you are tapping your own tee nuts, use a taper tap and don't go all the way through. Easy way if you use all thread as the studs to stop the stud winding right through the nut, can keep the nuts nice and tight on the stud too if required.
|Thread: Rudder Bushes on Boat|
Thorplas from Thorndon plastics is an established marine bearing material, the blue grade will be fine, it's available in cored rod form so not too much waste. Quite expensive though if I recollect correctly. As already said nylon is no good as it absorbs water and will swell, which will mean your rudder stock will be well and truly stuck!
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