Here is a list of all the postings fizzy has made in our forums. Click on a thread name to jump to the thread.
|Thread: Dome bush|
it wouldnt be possable to profile a bush and still have it going into the boiler, unless your bush just sat on the outside of the shell. Either way if youve got it silver soldered in and there are enough threads it makes no difference.
|Thread: Model boiler safety calculations|
Duncan - this is the spreadsheet which those of us in the industry have used for a long time - I did know who originated it but have lonf since forgotten. You cant use your download as it is Locked for Editing. Assuming you have excel as soon as you open it it should tell you this at the top - click unlock and your good to go. I have used it on every boiler I have designed (quite a few!) and it has never failed to produce a boiler which did what it was supposed to do. That said there is an anomoly with one of the stay calculations but it over compensates so is fail safe. I think the biggest problem is, even with the data/formulae that knowing how to implement it requires considerable knowledge and understanding of boiler making. Once I have the data required I apply it in a cad drawing using stress zoning for every stay and flat area. Only then can you clearly see if youve covered all areas of the build - sounds complicated but its very simple if you can use basic cad.
Sorry the one at the bottom of Johns link is the one to use - Can you please send me a copy olde friend?
Theres a spread sheet which covers every aspect of safe limits and thickness...ive shared it with several people over the years and now no longer have a copy! If anyone could send me one back I would be grateful.
|Thread: Replacement motor control box for mini mill|
gave mine to our super elec tech at work to fix (bloke is a genius) and he couldnt fix it! Mine now has a drill motor with no speed control but at least its super reliable.
|Thread: My Corliss build|
Over the Christmas period using the MEM designed plans I have completely re-drawn the Corliss engine and scaled it up by x 1.5. There have been a lot of small changes to the original plans but the geometry is pretty much the same. So I thought I would share a few photos of the build so far - its a very heavy thing! For some idea of size the cross centre of the crank arm is 1.125" A big shout out to JB for his kind help.
Edited By JasonB on 17/01/2021 17:30:25
|Thread: Cleaning copper rivets.|
There is no point to cleaning the rivets as they will revert back to this colour the first time you fire the boiler. Your flux will do the cleaning as far as the joint goes. It is definately against the law for joe public to buy Sulphuric acid above 15% W/W however suppliers routinely sell Drain Cleaner to the public which is 95%, indeed the only difference between this and the stuff they sell to businesses is the label.
|Thread: MIG Gas|
If youve ever tried welding with pure CO2 them moved to the mixed gas the difference is massive. CO2 is a horrid gas to weld with.
|Thread: Gloves and machine tools - my stupidity.|
I use machine tools every day, and for many years would never wear gloves, nowadays having bad psoriasis I have no real option but to wear gloves, indeed I rarely take them off.....but there are gloves and there are gloves. Mine are made specifically for machine shop work, no loose threads, indeed they fit like a glove! I buy them in bulk and they are about 60p per pair with a pair easily lasting three to fout weeks. They are coated with something on the underside so there is nothing that can catch. Regardsing the Op's post, I also have white cotton gloves for things like the gas tanks we make in brass, and can confirm that they are quite dangerous if used near turning things.
|Thread: From a leaky nose to a bent nose|
not a bent spindle - what do you percieve a bent spindle would do? non of the proposed issues would show as a face plate out by 10 thou per half revolution...parts are rocking well and good...bent spindle. The other factors wouldnt cause the face plate to wobble.
Its taper roller bearings from (I think) the late 40s. I would tend to agree with you except when I put a dti on the face plate it was not good! Everything clean so no swarf behind it. I managed to take a thou or so off the face of the spindle which reduced the offset but its stil out. For everyday use It does what I need but no good for boring to within a thou.
Just coming to terms with the oil leak and concluded the nose is bent on the L5. Had to bore a shaft with a 1.3" id over 6 inches long for the Corlis. No matter what I tried I ended up with one end ten thou smaller than the other. Put the face plate on and what do you know - well out. I managed to face the nose shoulder and rebore but it was still six thou out. Most frusrating! Time for a better lathe me thinks.
|Thread: Leaky nose?|
oil level lower than it should be i think, although I have yet to discover where the oil level is, and ive tried to find out. there is some SKF square section felt on ebay which looks like the original stuff so i will try that first. Thanks all.
I ran it with the filler cap off so no back pressure - still leaks. There is a collector and hole in the front plate but strangely no where for it to go back to the sump. Its new felt that I need....just couldnt think of it. will look see if they make it in square section.
My harrison L5 is about 70 years old and performing well - except ive got an oil leak from the main shaft/nose interface. Ive tried revitalising the original wiper and tried graphite yarn but to not much avail. Im thinking of fitting an automotive type crank seal but does anyone have a simpler idea? thanks
|Thread: Drilling through bronze|
Make it out of Colphos....machines like a knife through butter
|Thread: Cheap Ultrasonic Cleaners|
Beware the cheap ones arent ultrasonic despite what the advert might say. I did a fair bit of research and didnt buy one in the end as any half decent one was bigger money than I wanted to spend.
|Thread: Boiler bush threads|
just to add....if im doing a decent sized loco boiler the bushes are 90% drilled, soldered in and drilled and tapped cold. The amount of heat that goes into a 5" gauge boiler is unreal and controlling it is difficult. On the small stuff which I do most (3.5inch dia to 6inch dia) I have cnc bronze bushes made. Sometimes silver solder will creep up and over the face and into the threads but chasing them out is easy enough.
|Thread: Free inserts.|
and me please...i just did the same and got the wrong size, if we swapped we would both be happy!
|Thread: Boiler bush threads|
You can use fully formed bronze bushes without issue - I use hundreds and have yet to have one fail. If you were to use brass then there is a high chance that the whole bush will melt and the threads dont like the heat regardless so dont go there.
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