|H D||02/12/2021 12:32:22|
|6 forum posts|
New to forum, new to manual lathe.
I do not know in depth terminology,
Did some cnc lathe programs 20 years ago...
Couple of days ago got my "new" RandA A
Actually (go figure) it is not new and is in quite bad shape.
But it cuts - tried on ali bilet - does the job - I guess it is nuke proof beauti.
It is enough for me - I am not searching for microns, but...
I would like to fixit a bit.
There are almost no gears to transfer power to lead screw.
Lead screw works ok with the saddle - no much unwanted movement - could be bit smoother movement.
There is huge movement on cross and top slide.
I cannot move the tail stock...
That is it for an introduction of Me the beast and the RandA beauty.
Appreciate any word on how to start with this lathe to bring it to proper state
as this piece of history (lathes.co.uk provides nice story but no technical advice) deserves
4912 forum posts
Post pictures for people to help you get going
|Clive Barker||02/12/2021 14:05:36|
52 forum posts
Hello HD, Welcome to the forum, not that I am a great contributor - but I thought you deserved a welcome and some encouragement. I looked up the RandA. It looks like a great little machine. It sounds like it is going to be difficult to get the screw cutting operational without undue expense/time and effort. Perhaps the saddle and cross slide issues are just a question of dismantling cleaning and readjusting the gib strips. Possibly the same with the tailstock. Clive.
|H D||02/12/2021 15:26:15|
|6 forum posts|
Thank you for welcome Clive.
I do not keep high hopes for thread cutting facility to be fully restored. Quick search on ebay for parts resulted in 0 listings. As it was released under other brands maybe I will find some replacements among Winfield Grayson Zyto but it is cross checking exercise.
First good advice would be what chuck I can fit there. I need 4 independent jaw chuck for it as this one has only 3 "outer" (do not know the term) non-reversible jaws (inner set is missing). I will take some dims soon. This will be really helpful as at some stages of the machining I need to fit rectangular work piece not on the center line (don't want to play with shim pads or others stuff).
Cross slide and top slide have movement in screw axial direction - so I guess it will be the case of fitting new nut/thread (I did not have a look inside yet to see if there is correction in that direction - to exited to play with it and unfortunately discover more things that are to be fixed).
Saddle/lead screw is probably a good cleaning job and greasing.
Paint to be stripped.
Belt need a proper tensioner pulley (first job on the lathe?).
Motor would use a bit of service too.
I will post some photos soon.
Edited By H D on 02/12/2021 15:30:53
|noel shelley||02/12/2021 16:29:02|
|1022 forum posts|
Welcome HD ! There are many on here who will be able to help you, but be wary of using grease on a lathe mostly it should be oil - SAE 10 or ISO 32 ( same oil just different numbers ) a light hydraulic oil ! Noel.
|Howard Lewis||02/12/2021 16:29:47|
|5751 forum posts|
You have found the right place for help.
Don't know the R and A, but there will be others on here who have and / or know it and can provide fdirst hand advice. Would guess that the threads used on the machine will be Whit form, so BSW (coarse ) and as the name implies BSF.
Where are you located?
If you can find a model engineering club within a reasonable distance, join it.
Some face to face tuition will be most useful, in all respects.
My two penn'orth
To learn the names of the parts of the lathe, and how to set it up and use it, buy some books, (Always useful for reference as well as being learning aids ).
If you wrongly name a part, either your question will not be answered, or will be misunderstood, and you will get an answer to a question that you have not asked, or one that you do not understand.
Firstly, you will find a set of Zeus Charts an invaluable reference
Ian Bradley "The Amateurs Workshop" Covers benchwork as well as lathework and setting up a lathe. Possibly a bit better in some respects than the "bible"
L H Sparey "The Amateurs Lathe".
Harold Hall and Neil Wyatt have both written books on lathework.,
For more detailed questions, books in the "Workshop Practice Series" will be useful as you progress.
Tubal Cain's "Model Engineers Handbook" is also an invaluable reference on many subjects.
Changewheels; Those for the RandA may not be the same as ones for other lathes in dimensional aspects (Bore, Width, Diametric Pitch, Pressure Angle to blind you with science ) so only use ones to the correct spec.
You may find them difficult to come by.
ALL machines have to have clearance, otherwise parts could not move relative to each other.
It is not unusual to find 0.020" backlash in Cros S;ides and Top Slides. The essential thing is to be able to deal with it.
So, if you overshot when putting on a cut, withdraw by almost one turn, and then wind back in to where you wanted to be.
In this way, picking figures out of the air, a Slide with 0.025" backlash needs to be retracted by more than 0.030", by at least 0.050" so that when the handle is wound in again, the backlash has been taken out.
You also need to ensure that the gib strips are correctly adjusted. They keep the slides in close alignment, ,but not so tightly that movement is hard.
Some more money to spend will be on measuring equipment, if you do not already have any. A Digital Calliper (About the cheapest will be from somewhere like LIDL or ALDI, for about £10. Better will be a Moore and Wright from someone like Machine DRO for about £24.
Your lathe is old, so will not benefit from, or be suitable for carbide tooling, so High Speed Steel should be your choice. To sharpen HSS tools and toolbits, you will need a bench grinder. The books above will tell you about the angles at which to grind.
Tools should be mounted with the cutting edge on centre height, if they are to cut properly.
When you get a 4 jaw chuck, (You may very well have to make a backplate for it. Which will initiate you into the joys of drilling and tapping as well as turning and facing )
Centering work in a 4 jaw will launch you into more measuring kit, at leasat one Dial test Indicator and a Magnetic Base. This will allow you to centre work in the 4 jaw more accurately than a 3 jaw.
It is MOST unlikely that you will find a 3 jaw chuck that holds work absolutely concentric
So, a lot for you to mull over! already.
|Nigel Graham 2||02/12/2021 19:02:36|
|1898 forum posts|
Regarding the change-wheels (which you combine to the appropriate ratio to drive the leadscrew from the spindle for the thread or fine feed you wish to cut), you might need determine the appropriate sizes and tooth-counts that will fit the machine, and buy a set of commercial stock gears.
It would not matter if they are metric (module system) or inch-based (Diametral Pitch or DP) because it's the tooth numbers that do the thing, but you may need either accurately bore out or bush their bores to fit the lathe. That is a 4-jaw or faceplate task, involving very careful centering. Easier and better if you can adapt them by bushes.
NB though - if you also have or obtain and of the original gears do not mix them with the new, as they would be unlikely to mesh correctly if at all, and you'll just wear them unfairly.
Others have suggested you'd be better using HSS tools, for which you'll need a bench-grinder of course. I agree! Many model-engineers enhance a standard bench-grinder by adding quite simple tool-rests adjustable to guide the tool consistently at its various angles. The grinder and tool-rest are screwed to the bench or a base-board, next to each other.
One source of help here, and for other reference books, is Harold Hall's Tool & Cutter Grinding. This book is in TEE Publishing's 'Workshop Practice' series, for which I can vouch - I have several of them. Peruse its on-line catalogue.
Carbide insert tips are not made to be re-ground even with the appropriate abrasives as they are made as short-lived industrial consumables whose prices are factored into the production costs; but you can sharpen HSS tools with an ordinary bench-grinder, and just lap the cutting edge with an oilstone slip for better finish. Far cheaper too!
Be aware what material you turning, too. Free-cutting mild steel machined with a well-sharpened and set tool can give a lovely finish, but a common beginner's query is why some apparently nice piece of steel turns horribly despite heroic efforts.
One likely answer is using "pre-loved" steel as many of us do, without knowing what it really is . You might be lucky and obtain good results, but often it's some unknown alloy needing specialist treatment. Or it is just cheap-quality steel like some old cable-drum tie-rods I have!
In this respect HSS cutters can sometimes give a better finish than carbide, because many alloys need very particular inserts.
|H D||02/12/2021 20:14:34|
|6 forum posts|
Hi all and thank you for advice.
Some things I do know some I did not. In any case It is good to have a reminder. I am not complete engineering newbie.
Other matter is English it is not my first language so for example things like grease and lubricant even if I do know technical difference I may misuse the words... I would not misuse them on the machine
Regarding movement on the slide screws - I do not mean clearance - I mean MOVEMENT (in big letters because it is quite amount ) about 1mm
Lots of books proposed to be read... I am rather hands on person - somehow with touch I learn better. I will follow some of the the suggestions.
Model making - I am not model maker - I purchased the lathe to make couple of components for my robot/rover. I knew it will be steep learning - especially when buying lathe for rebuild. But rebuild/refresh will teach me a lot.
Yet after initial fun - I see that I will be using this for much more. And watching how material is shaped by the tool is mesmerising.
Photos as promised - it does not look that bad - but the devil is in the details.
6182 forum posts
Find the search facility on the front page of the forum. There have been several threads about the RandA lathe in the last couple of years.
Don't rush into anything. I can give you some more info when I have read all the posts in this thread slowly. It might be better to not get changewheels yet and consider using the plastic sets sold for mini-lathes.
If you are enthusiastically taking bits off beware this. The apron, plate that hangs down from saddle, has a handle to move it and a lever that lifts the half nut up onto the leadscrew. This lever has a small spring and ball bearing to provide a detent in two positions. The ball bearing is magnetically attracted to the floor underneath your bench and the spring is designed to achieve escape velocity as it heads for the open window.
Edited By Bazyle on 03/12/2021 00:15:15
|H D||03/12/2021 06:47:00|
|6 forum posts|
Good one Bazyle - always wanted to be an astronaut,
Have been thro all the RandA posts - there are snippets of info. May be useful in time.
I am not going to put all apart at once as I need it to do some job for me first. The plan is:
0. Find some time from other works (house build project, heat recovery unit project, christmass special projects)...
1. I am going to make a good sturdy place for it (destination is brick wall mounted heavy counter top - should do as a base initially) and fix it down.
2. (need to run - will finish later )
|H D||03/12/2021 13:29:03|
|6 forum posts|
2. Have a look into slides and try to cancel excessive movement without spending money (mainly assessment)
3. Make a tensioner - with pulley machined on the lathe - to cancel unnecessary vibrations from there
4. Do some work (axels, spacers for my wheeled robotic platform WaRP)
5. Return to slides with possible replacement components...
6. Refresh main screw/saddle (trying to avoid a visit to the orbit in search of the spring)
Taking into account other rolling projects... I am set for next 6 months...
6182 forum posts
By the way I suggest you try and rig up a countershaft rather than a tensioner. You really want a 1:2 reduction from motor to mandrel as the top speed for these plain iron bearings. You can make rig with plywood pulleys.
|Howard Lewis||03/12/2021 18:19:06|
|5751 forum posts|
A lathe of any sort is far better than trying to use a pistol drill and a file to reduce diameters.
It will become a much used and versatile machine .
You can use it make some of the new parts fro repair, or improvement.
Do not worry too much about it's age. It may not have electronic speed control, or digital read outs, but can do splendid work on it. It will be very useful machine as you become accustomed to it.
By all means read books on using a lathe, you will learn and gain confidence and experience.
As the English say "Many a good tune, played on an old fiddle"
|621 forum posts|
try and find somebody local who will help u with the odd stuff.....is there a local Mod eng club near u.....?
U say English is not ur first language...but are u in the UK...? if so should be easy to get help......
I'd gladly help but I'm a 1000miles away and incedentally here in Crete it's hard enough to find a proper engineering shop with a 2.5 hour drive (each way)...
|H D||04/12/2021 11:08:07|
|6 forum posts|
I bet there is plenty skilled people around Swindon where I live.
I have been to Swindon maker place - really nice machine shop. With people who know their stuff.
The problem is spare time and state of my projects. To work there I would have to: find the free slot, load in what I need to do the job, drive whole 10minutes ....
To be fair - I do not like to use somebody's tools it is bit invasive.
I may take my little beauty for consultation there (I wonder what the doctor will say) but I rather keep my works at my place where I have access to all my tools and I know where all is placed.
Howard - I do agree - a lathe will be better than drill (never tried - previously if I needed something being cnced, machined, welded - I sneaked in a dwg, cnc program to the workshop... I do not have workshop in my new company ) I am project engineer and I have spend a lot of time with machine operators to squeeze every bit of functionality out of the machine.
Bazyle - I may do the reduction in not far future - I have loads of quite ok s/s shafts laying around, ply I have is not that great but I do have offcuts of oak worktop - hardwood should be ok. So far I have spent my pocket money for RandA itself, so I am not planning for more expenditure (apart maybe 4 independent jaw chuck). I have scavenged lots of nice materials that would be thrown away otherwise (dc01/cr4 steel, 304, some ali, acrylic, pet, pc all that mainly up to 5mm sheets). I could use some of nylon - I guess I will have to purchase that.
Edited By H D on 04/12/2021 11:09:10
|Howard Lewis||04/12/2021 21:12:53|
|5751 forum posts|
Material is only scrap when it is too small to hold for machining, or is already swarf.
Whatever it is; it will come in handy one day! Possibly a desperate repair job at 10:00 pm on a Saturday night!
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