Here is a list of all the postings Brian Wood has made in our forums. Click on a thread name to jump to the thread.
|Thread: Flat bottom hole 3/16 o/d|
The usual approach is to drill the hole almost to full depth and then swap the drill for a specially ground flat bottomed drill to create the bottom of the hole.
The skill lies in getting the geometry of the second drill end correct but it can be done in drills of this diameter. In my professional life we used to call on the services of a particular man in the toolroom to create flat bottomed holes in all manner of exotic aero engine materials. These were 0.050 inch diameter [ actually 3/64 inch] and about 1/2 inch deep. Skilled work indeed with sensitive drilling machines.
|Thread: CovMac Lathes|
All exciting stuff isn't it, eat your heart out Chris!
I recently rescued a Churchill Cub, made in 1947 which I am restoring. Not in Covmac scale but large for me. The motor on that was enormous, a two speed 3 phase unit weighing 55 kg, it was about all I could do to push it about on the floor. All that for 1 HP
I shall be running the lathe with a variable speed 240 volt 3 phase unit when that happy day comes about, the difference in weight and performance is remarkable. The new motor weighs 17.3 kg and delivers 2 HP
The old motor stator will be reused as a demagnetising tunnel with a central plastic tube fitted in place of the bell ends.
Edited By Brian Wood on 10/08/2019 14:11:52
Good to see more progress! What power of motor have you settled on to run the old girl on, it must be fairly substantial to justify 5 belts?
|Thread: Bulking problem?|
Thinking about Ron Laden's suggestion of binding with string, I think that could be a winner. Old time stick makers wouldn't have had a lot of tackle, such as an array of hose clips, to reduce the size of a horn, from whatever animal it had come from, so reducing it gradually with it bound tightly after boiling to soften it and letting it set thus clamped was probably how they went about it.
Repeated treatments were probably needed, I would not expect final size to be achieved in one hit.
Is is possible to make the horn material flexible? Steaming comes to mind, it is after all made of something akin to finger nails and I imagine that can be softened with heat at those temperatures.
Rather than try a collet chuck, which only closes over a small length to pull in a steel collet, I would be tempted to try a series of hose clips over the length you want to squeeze.
PS There are plenty of stick makers up here in Yorkshire, sheep horn seems to be the favoured choice and those are manipulated I feel sure.
Edited By Brian Wood on 09/08/2019 18:28:18
|Thread: EUREKA Gear-Tooth Relieving Attachment - Ancient History....|
Thank you Michael, I stand corrected.
I too have taken a great interest in this device.
My research confirms the Balzar device as a geared piece of tooling and that it was granted a US patent in 1895.
Robert Taylor was granted a US patent for a ratchet operated device in 1906, but by this time the German tool company of Selig Sonnenthal had an almost identical piece of tooling on sale in 1904 at the price then of £8 a time [equivalent to about £900 today]
The illustration that Andre refers to is of the Sonnenthal equipment and this is what Eureka was based upon
In Ivan Law's book, Gears and Gearcutting #17 in the Workshop Practice Series, Chapter 12 there are drawings and text for making Eureka.
|Thread: Floor Paint|
Perhaps it might be better to abort the idea Neil and go for fitted carpet instead.
I have floor paint straight onto concrete in my workshop. The paint was formulated for the job and it has to date done about 20 years. The gloss in now rather matt in the highest traffic zone but it is still intact and it gets a lot of swarf etc trodden over it.
These paints however are not really in the domestic colour chart range. Mine is a strong red, chosen from a rather limited colour palette at the time
I don't know if that help you, but it is what I might do in the circumstances.
|Thread: ML7 lathe carriage|
I haven't carried out the pinning on the jibs so can't comment on that aspect. Your other question on the jib itself, they usually had pockets for all the adjusting screws
|Thread: Myford super 7 Tailstock Spindle Damage|
I too have cleaned up the morse tapers on tailstock barrels, but I adopted a much gentler way of going about it
I gripped the tang end of the correct size reamer in the bench vice in one instance and pushed the barrel onto it while rotating it by hand. You can 'feel' the cutting that way. I haven't measured the result as the lathe is being refurbished but taper shank drills fit with a nice 'kerthunk' noise and grip properly
In the second case, a 3 MT version, the tailstock barrel [18 inches long and heavy] was gripped via a cloth in the vice and the reamer turned by hand in a big tap holder, using the tang gripped between the jaws of the tap holder. Later measurement on a precision bar at 5 inches from the mouth of the barrel gave a run out of under 0.001 inches and again there was the satisfying 'kerthunk' noise on fitting drills
|Thread: What mills have you had|
I made my Mk 2 Dore-Westbury which I still own, admittedly a light machine which now has variable speed drive, a big improvement. It get a lot of use.
A Tom Senior [Junior] horizontal mill, a lovely machine, which I use for gear cutting
And not listed as a category on it's own, an Elliott M 10 shaper
|Thread: What lathes have you had?|
Myford ML4 inherited when Dad died. Sold to buy----
A good Myford ML7 from a trusted friend. That was a good lathe but sold to buy----
Another good Myford ML7 R, which I still have and use. It is much modified.
Smart and Brown Sabel---a nice one and I use it
Churchill Cub, a rescue project recently taken in hand. It will be good when it is done
Edited By Brian Wood on 21/07/2019 18:35:25
|Thread: Saying hello from Cheshire.|
Welcome aboard Tommy,
I am not into clocks, machine tools and tool making are my main interests. You will though find many kindred spirits here
Edited By Brian Wood on 20/07/2019 17:10:56
|Thread: Colchester Chipmaster|
You may have to make one by filing out a square hole in a piece of drilled bar and then welding or brazing a T handle or similar to it.
If you Google square chuck keys all you see are the male versions and looking for hollow square keys only seems to go up to clock winding key sizes, nothing in the size you need..
|Thread: Steel boiler storage.|
You secure it mechanically so that it is in good electrical contact
I too will miss your input. It has given great value, knowledge and experience to the rest of us on the forum and it seems a great pity that some feel it has no place here, based purely upon the scale on which you work.
I do hope you will reconsider and return to us. As others have said, the forum will be a poorer place if not
Kind regards Brian
|Thread: Cutting a Mod 1 worm|
How very flattering, I'll do what I can to help.
I am not familiar with your BL12-24 lathe, but I suspect it will have a 40T gear off the spindle permanently included in any change wheel set up. I don't know how comprehensive the Norton gearbox is either, so a picture or two to enlighten me on those aspects will be helpful; plus of course your spreadsheet.And a picture to show how your changewheels are arranged on the banjo would be helpful.
Do you have any feel for the ratios the gearbox provides? One way of establishing that is to take a look inside and count the teeth on the input gear, then count the teeth on the cone of gears that can be selected. I can work out what that gives as ratios if you would prefer not to.
I hope it won't be necessary for you to make other change wheels, we'll see.
My email is wood_y(at)btinternet(dot)com all in lower case, no spaces and note the underscore between d and y
Hello again Howard,
I can save your brain cells some, but not all, the work.
The basic gearing calculation is really not too difficult. For this example we do need to incorporate an approximation for pi/2 in the gearing, which is neatly given by 55/35 to an error of roughly 1 in 2000
The full sum therefore becomes required Pitch P = 55/35 x R x Leadscrew pitch [ R is the combined value of change wheel ratio and in your case a gearbox ratio]
Putting in the known value for P = 3.142, we can rearrange the formula to find the value of R
R = 3.142 x 35/55 x 1/ Leadscrew pitch [1/3 in this case] which gives a value for R of 0.6664
Without knowing what change wheels you have available, nor the gearbox ratios that you can call upon, it surely can't be too taxing to find values for these components in the calculation, which multiplied together amount to 2/3
|Thread: Myford ML4 backgear disassemble|
I'm sorry to be late in reply to your question, I have only just seen it. From fading memory now, I recall that the backgear cluster that fits onto the eccentric that is used to swing it into and out of engagement is retained on it's shaft with a broad washer and countersunk screw, fitted to the 'motor' side.
Remove those and slacken the nip bolt that proves an adjustable grip to the shaft in question [to give it some resistance to turning], the shaft should then withdraw towards the tailstock end of the lathe.
I have a new and unused 65 tooth bull wheel available to fit the main spindle, teeth often get broken off those and they are no longer available as spares from Myford. If you need one, send me a personal message (PM)
Good luck with the restoration
|Thread: Cutting a Mod 1 worm|
The error was listed in the table as mm, so the figure will be 0.001 mm [1 micron]
It is of course a calculated value which depends on the accuracy of the leadscrew on the machine in question. Having said that you could test the gearing on your lathe with a 60 T gear on the leadscrew just to see if you could cut that pitch, it would perhaps prove the point whether or not your lathe is capable of the task.
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