Here is a list of all the postings Zan has made in our forums. Click on a thread name to jump to the thread.
|Thread: Stuart Twin Victoria (Princess Royal) Mill Engine|
Ah. Your beginner status shows again, but Iv been following your posts and your level of skill is impressive!
t bar, a very long t nut with tapped holes for the studs. Mine for the S7 are 4,2 and 1 inch long with holes tapped every .5” or so they spread the load and minimise the risk of damage. Also be careful the x slide is not bent when the clamps are tightened too much. I’ll provide a sketch of the clamping outlined above if you didn’t fully get it
The problem with a strap clamp like yours is that all the down force could be on a single pimple point on the valve face, thus you only have in effect one clamping point with a very high force on it. This makes them a bit of a problem compared to 4 clamps . Do be certain to use t bars not t nuts or there is a real risk of breaking the t slot in the cross slide, there wupill be considerable force on them
Edited By Zan on 27/07/2021 09:14:38
How about a short turned plug in the feet, then clamp each down with a long stud stud, clamp bar sat on packing
then add additional clamp bars to the same stud but longer bars going outside the lower clamps, so you now have 8 clamps using 4 studs There would be room in the centre for a strap clamp as well
it has the additional benefit of making the clamp positions wider on the casting thus removing the tendency of twisting
with regards to the feet fixings, I think it’s a mistake to tap the holes in the base. The wood plug cantering is very inaccurate and could easily be 10 thou out at each end, thus the bore is angled relative to your base fixings. The easy way is to spot through accurate fitting using plugs in the finished cylinder with reamed holes and a straight bit of silver steel as a pointer. Set this up on the bed, clamp in exact position then tap the base holes. You may find that to correctly align the cylinder ot will need some small rotation so the feet holes will need to be pulled over to allow this . I hope not
Edit…..perhaps you should rely on the position of the feet holes as you seem to have positioned these very accurately setting these parallel to the lathe axis, then just centering at the headstock end
Edited By Zan on 27/07/2021 09:04:08
Edited By Zan on 27/07/2021 09:08:09
|Thread: Downloadable issues|
I can’t download issue ME # 4669 in pocket mags or even view it in here. 4670, no problem works ok
I tried to use contact tab in pocket mags, it says the device won’t send mails! Ridiculous. I use it every day!
help or advice please
|Thread: Whittle V8|
So the drawing shows the right end of the jig calling it the front , not the front of the engine which is on the left in your photo with the drawing face outwards on the right, not facing the front of the engine ( actually at the back of the engine!)
Thanks emgee. Your shaft looks good! Indexing on both ends of the jig?
I joined the group and asked in there as well but still hoping for an answer in here
The photo shows the drawings. Whittle does not fully explain in his notes about the fixture. (Me July 95 #82) The indexing wheel is fixed to the back of the camshaft , his photos of machining it show this at the right on the Miller. However the drawing states only the “ front indexing plate” so is this a view on the END of the fixture OR the view from the Front of the engine/camshaft. I think it’s the former but if I am wrong the engine will run backwards or not at all
Any guidance from anybody who has actually got the engine running would be much appreciated.
Edited By Zan on 23/07/2021 12:35:14
|Thread: Stone moving machine|
Interesting concept but would be better just using balance without the turntable
I suppose the druids would just pop down to the local timber merchant fir the very very thick planks needed to support the weight, feet thick? then get them to send a forklift to get the stone onto the top…
Edited By Zan on 04/07/2021 11:19:12
|Thread: What RCD NVR for a workshop?|
My workshop electrics are fed as a separate ring main from the house consumer unit via a 30 amp trip
by the w shop door is a 24 amp large circuit breaker with built in trip. This means any shop problems do not trip the main house unit. I use this as a main power switch and turn all off when exiting, so all the led machine lights and other stuff have no chance of running without me there. It has worked brilliantly for 18 years.
|Thread: Surface finish when turning.|
What speeds and feeds are you using?
|Thread: Pitch Circle|
Ps it seems that with your crank problems, you will need a serious lot of checking at all stages of this build, as you have now identified two areas of error.
As most drawings are produced by amateurs working in home workshops, and detailing what they have actually made the drawings are only as good as the skill of the designer in fully detailing ( or remembering ) any changes which had to be made as the build progressed. All drawings thus should be checked as far as possible for correct dimensions as it can lead to complications. I am making a loco donkey pump at the moment, using magazine drawings. The height if the pump block was given in its main drawing at 1/16” less than shown in the later drawing of the water passageways . This I missed this, so it gave me headaches to sort out, solved by making the top plate 1/16 thicker to make the block big enough for the stroke of the pump , but I still had another couple of mods to make to sort things out. The drawings for this loco build are tremendously accurate with tiny clearances and I trust them! It is essential as even with careful checking, a component assembly may have been made a long time before adjacent components are fitted, and mistakes in the drawings may not be spotted even with diligent care But as seen problems still arise. I suspect the problem this time was with the draftsmanship of the magazine employee rather than the designer.
if you make and measure where do you start? Something is needed to measure! It’s all part of the process as experience and knowledge of interpretation of drawings and the reality of construction grow. But it also needs common sense, you can’t drill holes in fresh air! Your case was a simple printing error . One of the advantage of producing 3D cad drawings is that the dimensioning is automatic to what has been created and such printing errors in both your and my case would not take place! But again, that depends on the designer actually doing that my designer does not use cad, and I am constantly amazed at his skill.
|Thread: 2D and 3D Cad Software Recommendations|
Although the free version of 360 has reduced the availability of drawings ( only one drawing sheet per file), they are still possible within the 10 active file limit. It just mean a bit more work on the aspect of which file you keep editable
it takes a lot of effort to learn a new application even if you are familiar with either 2d or 3D cad, they all work differently. I now find fusion a bit frustrating, but i am certain it is still the best free system availiable
|Thread: What lathe pointers|
If there’s 5000 members of this forum, there’s 5000 different answers. Every single person has different specific needs and space
|Thread: Calculating Diameter|
First you need to decide the thread form whitworth or metric
then you need to determine the pitch if metric or tpi in imperial eg 10 tpi or 2 mm
then get some tables which will show you the proportion and the maths eg, pitch depth is .64 x pitch
then calculate the numbers from the thread profile data
too many unknowns at the moment except your stated diameter, but in wood, you will need a coarse thread to five any real strength
|Thread: Can anyone help|
What’s the centre height? More info needed. What have you got? You say “another”
|Thread: Taper due to tailstock height misalignment.|
Tom Walshaw, or George Thomas did a study of this about turning morse tapers and the usual advice to get the tool exactly on centre. I seem to remember that even a 10 thou error made almost no difference , units on less than 10th of a thou difference, and the conclusion was that the top slide dovetails would have more error
|Thread: Master key - precision chuck.|
So so easy to find out. Just Chuck a piece of very round material. Tighten with each socket in turn noting the dti deflection. Remove bar, rotate it a bit and repeat.
if you want a more accurate test, repeat with different dia stock before marking.
Not much faff, it will only take 5 mins
Edited By Zan on 03/06/2021 14:35:25
|Thread: Myford extension for spindle.|
Would be very useful when using my Myford captain thus allowing use of the cross slide for cutoff on my short bed S7
|Thread: Injector LBSC type|
So once again, how much is just less or a bit more? Just as bad as full and bare 5 thou? 10 thou? 15 thou? 1 thou? I think dimensioning in this way goes back to the time of a combination of rulers, odd legs and callipers, and has no place in the modern workshop full of cheap digital equipment . It’s why our creations are so so much better in both fit, detail and interval between maintenance than in the past
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