Here is a list of all the postings Oily Rag has made in our forums. Click on a thread name to jump to the thread.
|Thread: Tapping (full depth or reduced)|
Are you using Taper/ Intermediate / Plug taps? or do you 'short - cut' by just using Taper / Intermediate and then a Plug tap?
There are so many approaches to consider - material being tapped, type of tap (straight flute, spiral flute positive, spiral flute negative, let alone ground thread form or not, carbon steel, HSS, HSS coated,.......). As the barmaid said to the vicar "its also all about lubrication".... Rocol RDT fluid? Ambersil Tuffcut paste? Russian Fat?
Every tapping job is different, and from my experience one of the most difficult has proven to be 1/4"BSW /UNC (never had the pleasure of doing anything less than a 5 BA) in 'sticky' steel. However, I agree that the tapping recommendations for the past erred on the side of caution and agree that a 65% thread engagement is generally sufficient and would also add that ensuring a 'straight' engagement is preferred above all else, for free hand tapping I use a 'bell' tapping guide, otherwise tapping from the pillar drill or mill as appropriate.
Now my question is what do you do about tapping an Acme thread?? Full engagement? 90%, 75% ???
|Thread: Now is a good time|
An interesting subject this as none of us enter into making a will gladly, after all, its an admission of our own short tenure on this earth. But wills also need to reflect the dynamics of life and therefore they need to be amended from time to time as beneficiaries circumstances change. I have recently modified my will in light of changed circumstances within the family (my daughter now lives abroad so to ask her to be an executor would put strains on her work career).
Basically, I have left all my tools and equipment to a young son of a longtime friend of mine. He is a good engineer and although more inclined to the art of fabrication (sheet metal work) he does have a lathe and mill and I know he can make good use of my 'kit'. Originally the will required the disposal of the tools with the aid of advice from several people to ensure she was not ripped off, but as I joked to the wife many years ago "when I go you will get the benefit of the proceeds of my workshop - when you go however, what am I going to do with 76 pairs of shoes!"
Everyone keep safe and well, please!
|Thread: Using EZELAP sharpeners|
Honing is finishing by removing very tiny amounts of material. Honing a cuthroat razor on a leather strop works by 'straightening the edge' but you can't hone the bore of a cylinder like that!
No you can't - but you can 'cork' a cylinder bore as a final action to remove 'spalled' material. I was always led to believe that honing is actually a surface finishing rather than a true machining operation, in that you cannot hone to a form - it will always follow the form of the previous fine boring operation.
A point about cleaning diamond hones is to use a school eraser, the rubber will remove the 'cr&p' out of the hone quite nicely.
Edited By Oily Rag on 23/03/2020 12:09:55
|Thread: Electric welder at Lidl|
"It says ‘from Leicester’, but like most, it will gave been made in china."
Must be from ARC Euro Trade then!
|Thread: Can anyone identify this power hacksaw|
I would hazard a guess that it is a bit of 'Lend Lease' equipment dating from early 1940's - probably something like a Millers Falls manufactured in Massachusetts USA. It looks to be something which may have been used in a REME mobile workshop or a LAD (Light Aid Detachment) mobile workshop of the Royal Armoured Corps, or even the American equivalent. Small enough to do a competent job but not of overpowering size as would be required in industry.
A few close up pictures may help! The finish on Millers Falls products was generally to a very high standard being black enamelled with red lining, but of course, war grade finish may have been the order of the day.
Well worth restoring and a valuable tool in its' own right.
|Thread: Cast Iron Watch Case|
If you don't want Berylium copper how about AlBeMet??
|Thread: Hobbymat lathe - couple of questions|
Chris, just a thought concerning the chuck jaw numbering which no one appears so far to have mentioned. Are all the jaws undamaged as far as the scroll teeth are concerned? I once bought a good looking Pratt Burnard chuck from 'Tractor Clear Out' event which had very little use - but I found that the 'thin' scroll tooth on No.1 jaw was broken, this meant that as it was now 'out of sequence' it was fitted last - so the fitting order became 2 - 3 - 1 rather than 1 - 2 - 3! Its worth checking.
My other thought is concerning making a T slot plate in steel - beware that the plate is liable to warp when you cut the T slots especially if the overall thickness is on the minimum side. Cast iron is far preferable from a stability point of view.
Best of luck with the machine - I hope you get many hours pleasure out of it.
|Thread: Temporary oil conundrum|
Haha! That reminds me of the time I was an apprentice and I discovered the Jig borers at the factory I worked at were using Newton Oil version of 'R' - It just so happened I was riding a BSA Gold Star (DB32 Clubman for those interested) that ran on 'R'. From then on I was taking a bottle a day home! The guys told me it was run on vegetable oil as it was the best oil but it was impossible to run in road vehicles - except mine I explained!
|Thread: Another "What is it"|
NPL refers to the National Physics Laboratory - the go to place for anything to do with measuring, based I seem to remember around Glasgow. Sigma was based in Letchworth and were a well respected instrument maker.
Edited By Oily Rag on 11/12/2019 15:16:34
|Thread: Arc euro micro drill adaptor|
As I said in my post above RMA - they do a job for a price but you need to be the judge of how good your other equipment is - high speed is the answer to drilling small holes, especially so when using carbide drills (I used 3mm shank drills with reduced sizes of 0.8, 1.0 and 1.15mm - I believe they are PCB drills). I was using my mill with its high speed head, the quill drive on the HSH is sensitive, but not sensitive enough for when you 'break through', that seemed to be the point where the drill would break and sure enough one broke, even with the Arc sensitive attachment. Be prepared to do some fettling on the shaft as the 'slop' on mine was excessive, and to be honest the drill chuck supplied by arc was not what I would deem a quality item. But all in all you only get what you pay for these days. Am Albrecht attachment is the way to go but as mentioned above they are costly and difficult to find. I have now bought one (an Albrecht) for future jobs like the one described here.
The job described above was in 318 stainless so all in all it will probably work for you on bronze.
I'll second 'IanT's' comment concerning the spindle to sleeve having too much 'slop'. I bought one of these items along with a small chuck to suit as I needed one to progress a job I had to get finished. The job was to make an 'in cylinder pressure sensor adaptor sleeve' which mounted internally a Kistler 1604a pressure sensor into a 8.5 mm sleeve which passed through a water jacket in a cylinder head. The sensor screwed into a 5mm thread internally at the base of the 100+mm long sleeve and connected to the combustion chamber via 3 ports drilled at an angle into the end of the sleeve. I had an order for 16 of these adaptor sleeves and they were needed 'yesterday'!
The sensitive drill unit needed a 15 micron plastic 'wrap' around the spindle to stop excessive slop. I was drilling three holes - 0.8mm, 1.0mm and 1.15mm after spoting the angle face with a 3mm end mill and then centre drilling to get an 'toe hold', the material was 318 stainless. I set it up in the mill and running with the high speed head at 8,000 rpm managed to drill them OK with the loss of only 1 drill (yes - you guessed it the 0.8mm one!). Apart from the 'slop', which the plastic 'wrap' cured (more or less!), my only other concern was with the bearing which after drilling all 48 holes got rather hot and a bit clanky. I actually made 51 holes as I had to produce a 'qualifying' sleeve for sign off of the order - purchase could not believe that a man in a shed could do what Kistler said would take them 12 weeks to do and that I could do it for half their price!
Some of the 'process' photos required by the customer:-
|Thread: Turret drill|
Yep! I know the feeling, I suffer from the same all the time - usually it is 'where have I left my glasses?'
Thanks for the information - this machine was originally supplied by - DEC (Coventry) Ltd, of Manor Road, Atherstone. I do not know if they were the importers or just agents of the importers. I did find a couple of references to Masanas on the 'tinterweb' which showed a similar machine for sale in Spain (apparently it's a model TR1). They look to have been building these at least as the late 1990's. This one dates from 1987. On the Youtube site there is a Burgmaster which has been adapted onto, what looks like, a Bridgeport base (replacing the turret head of the milling machine) to provide it with a very adaptable x - y co-ordinate table facility. It is shown drilling the end plate of a steam tube boiler assembly!
The more I look at it the more I fancy 'that it will come in useful one day' - now where have I heard that before??
Edited By Oily Rag on 06/12/2019 16:23:18
Wouldn't use it for milling as I recognise there is little sideways support in what is essentially a drill, I already have an Aciera F3 and a Bridgeport for milling so no worries there! It is an interesting 'Production' set up as opposed to a 'gang' of bench drills which is the more normal approach to multi op drilling and taping. The x-y table was more to do with an attempt to get some accuracy in co-ordinate drilling of multiple holes - but on second thoughts it is probably easier to 'mark out' and pick up centre spots. I'm considering using it for crankcase drilling and tapping, which will need a minimum of 12, and upto 24 holes drilled and tapped, with corresponding clearance holes and spot facing.
One area which looks to be well thought out is the depth stop system for each individual tool station, as indexing the head turret also indexes a stop bar. The other bit of trick design seems to be that the turret head is programmable for speeds as it goes from station to station - but note that stations have explicit speed ranges.
Do you have any information on the Burgmaster that you quote John? Looked on the usual Lathes dot UK site but neither the Manamas nor the Burgmaster are listed.
Anybody know anything about these turret drilling machines? A friend asked me if I wanted it and although the workshop is pretty full I am tempted to make some room for it. I believe this may have been made by Metabo a Spanish machine tool company that also built clones of the Deckel FP1,and Thiel type mills. It has no 'moveable' table but could be adapted for a bolt on x-y table as long as it was low enough. It is well built and sturdy and too good to scrap out, plus it has a goodly collection of tapping heads (not the retainer plate of the one tapping head on the turret currently)
|Thread: Breaking bandsaw blades|
Looks like numerous others have pointed out, poor quality welding. I have a Chincom cheapo bandsaw which uses 1/2" x 0.025" x 64 1/2" blades. The originals supplied with the mahine (3 with various tpi's) lasted about halfway through their first cuts! Since then I have only ever used Starrett bi metal M42 vari-tooth blades - never had a problem with these, track well, cut well, and last an amazing time! Only time they ever struggled was when I had some copper berylium stock to cut - but then anything struggles to cut that stuff!
Cost was about £15 per blade from J&L (now MSC) in Wednesbury about 10 years ago, worth every penny.
|Thread: Cracking a bolt|
To measure the torque of a retaining bolt (or stud and nut assembly) the usual method employed by engine development engineers is to mark the radial position of the bolt (or nut) relative to a surrounding fixed point, then to 'break off' the fastener and then to re-tighten to 'mark' - this will give the torque load of a fastener assembly. Where an engine cylinder head is concerned the torque loads will vary according to differences in gasket collapse, local casting collapse, either through thermal cycling or casting imperfections, and also due to thread 'pull'. There are now, however, systems which allow the torque induced in the bolt (or stud) to be read by recording the 'pitch'when the exposed end of the bolt (or stud) is struck, this without the need to disassemble. This uses the similarity between a bolt and a guitar string in tension to produce a 'pitch' when excited - a higher 'pitch' indicates a higher tension. This system requires a correlation exercise to remove all associated variables such as casting material, cavity differences, and other damping inducing effects which may be present. So, it will only work in a production environment for a specific application and / but with a corresponding error bandwidth due to casting production tolerances.
As mentioned previously by another respondent, the best way to tension conrod bolts is to measure the 'stretch' of the bolt by a non rotating point anvil micrometer. Carillo rods using APC fasteners have a 'stretch value' defining their fitting tension - a typical value may be something in the order of 0.0048".
|Thread: Honing motor cycle small ends|
You may recognise the bike in my avatar photo then?!
Edited By Oily Rag on 11/05/2019 15:44:18
Edited By Oily Rag on 11/05/2019 15:46:07
A way of getting a reamer to cut oversize is to use a 'fag' paper on one tooth of the reamer, gives about a 0.0008" increase in diameter, 2 'fag' papers on 2 teeth give about a 'cow and a calf' - then hand scrape to finish!
Never ever be tempted to use emery or diamond honing paste!
|Thread: Bore micrometer|
Bowers 13-16 and 16-19 bore micrometers with their setting gauges. An excellent buy at an auction for £40 for the pair. I have also got some larger Mitutoya bore micrometers in imperial sizes from 3/4" through to 2.5" with some gaps in the range. Once set they are pretty reliable, but I do check them every time I use them. DBG's are good for checking bore taper and run-out but cannot meet the exactness of using a bore micrometer - these Bowers are graduated in 0.005mm but are readable to 0.002mm (glasses dependent!), especially where small bores are concerned and accuracy is required. I use these for little end measuring of con rods and pistons. The bigger imperial mikes I use for main bearing fits. I did have some Chinese small bore micrometers but given they were reasonably accurate they were poorly made to such an extent that the jaw on one mike dropped out! Their setting gauges were inaccurate when checked with the Bowers.
Edited By Oily Rag on 11/05/2019 14:23:48
|Thread: Hemingway Dynamic Toolpost Grinder|
Great series of posts Nick, very well written and good photos. Thank you very much for that. I hope the hangovers are not troubling you too much though now! (go and see the doctor if they are!!)
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