Member postings for JohnF

Dave aka SoD making an undercut at the shoulder is industry standard but doing it with a parting tool will potentially reduce the strength due to sharp corners creating stress points. Undercut tools as a general rule would be 1-1/2 x pitch wide with a radius on the corner adjacent to the shoulder and the "thread side" having an angle equal to half the thread angle or 45 deg.

John

I concur 100 % with Howard Lewis above --- must have gone to the same school !

John

The old "yardstick" for the drill size was reamer/hole size less 1/64" indeed the bushes available for jigs and fixtures from the main supplier for toolroom accessories for jigs, PTU [Production Unit Tool] were all to this specification.

However nothing is cast in stone you can be flexible depending on material, lubrication and not least what you have available ! Within sensible limits of course.

John

Hi Martin, I have an original Dickson Engineering installation leaflet and for the SO [Myford size] tool block it shows the optimum dimension of 7/8" form the lathe centre height to the top of the top slide and suggests 3/8' tool bits.

Unfortunately its a pdf document so cannot post on here. Hope this helps, if you want a copy of the pdf PM me with your email

John

Hi Terry, Here is a drawing of the arbor you need, I think the arbor you have is an updated one but this one is easy to make -- more photo's in my albums; John

Something similar came up on another post relating to ER chucks, accuracy TIR and fit. I had a problem with an ER chuck purchased from and made in Europe -- I eventually found out they were using UNF form threads instead of Whitworth form so I do wonder if some of the Far East product has the same problem ?

During my conversations with the producers of the ER chuck I acquired the correct thread tolerance dimensions for Go / No Go gauges for the "Myford" thread and made a GO gauge as close to these dimensions as possible with the equipment I have -- I am confident its close enough to the limits specified for practical purposes. I used a full form tip to make the gauge measuring over wires with an indicator micrometer.

The sizes were calculated as a favour to me by a UK gauge maker so I don't feel it would be right to publicise them, however if any forum members want them please PM me with an email address and I will pass them on.

Why any commercial company manufacturing a precision product would operate without the proper gauges is beyond belief !!

Another problem I have found with much of the imported Myford spindle tooling offered by suppliers is the register diameter on both male and female units is woefully outside the tolerance it needs to be to ensure TIR accuracy

Regards John

Photo of my gauge

Thank you one and all ! I have been otherwise engaged since my original post but at least its now explained -- I'll live with it !!

Regards John

Anyone noticed the strange type appearing in the RHS Latest Posts column ?

The actual title appear correct but see the examples pasted below of the latest post column

New Chuck won’t screw on

Centre Drill Leaves a “Pip� - Sometimes

John

I bought some last year from WDS components but not that size and it seems they don't have 7/32" they do however sell single units upwards.

Have you considered using silver steel and harden it ? The problem is the tolerance may not suit you and there is a possibility of distortion after hardening however considering the short length its likely to be less of a problem ! All depends on the actual use.

John

Edited By JohnF on 20/07/2021 23:06:05

Michael, the Emco has a self ejecting mechanism for the MT2 tooling, it uses the draw bar and the small cap in photo 1. The draw bars are Allen screws and with the black cap in place you unscrew the draw bar until it comes to the black cap then continue to eject the taper.

I appreciate you say the thread is damaged so maybe you cannot use this method, however the type of Clarkson chuck you have has a stabilising collar that is threaded onto to body of the chuck, during use it should be snugged up to the spindle face. You MAY be able to use this feature to release your chuck by using a spanner [supplied with the machines] on the 2 flats on the spindle and a tommy bar in the Clarkson chuck collar it will hopefully eject the chuck --- put something under it to stop it dropping onto you mill table !!

Hope this helps John

PS PM me with you email if you want a copy of the instruction book page, look in my albums at Clarkson Autolock

Yes Nigel it is close to Caton, next Village along at Claughton. Caton is my home town !

No the brickworks isn’t closing as far as we are aware, it was mothballed a few years ago for some time but I understand the raw material is of high value and something special! There were three brickwork’s at one time ! Two in Claughton, East works and West works plus another on the opposite side of the more Brookhouse Brick.

The chap on the video suggests the shale will run out in 15 years or so hence the possible closure however time will tell !

John

Hi All, It will/would be sad if and when it is dismantled, I hope that somehow it will be saved when the day comes as suggested in 2036 -- I doubt it will be my problem !! It is very quiet and efficient and some years ago there was a plan to scrap it and run trucks to carry the shale, the route was through our village -- after a considerable "fight" with the planners it was abandoned thank goodness !

Conversion to a tourist attraction sounds great but it would need a very large cash injection to come even close to standards necessary to carry people.

Cheers John

Hi Vic, "colour case hardening" its case hardening using bone charcoal, to achieve the finish the case is not very thick but enough to be wear resistant -- been practising and the tool was a prime candidate !

John

My contribution as well -- I "borrowed" Vic's design -- one of the nicest I have seen and made this a couple of years back - have a sketch somewhere !!!!

Hi all thought this may be if interest, its very close to me and in my opinion a cleaver feat of engineering.

**LINK**

Hope you enjoy

John

Michael, one way of removing the bricks is drill a series of holes through the mortar bed as close together as possible then use on of the carbide side cutting "drills" aka Screwfix etc that fit an angle grinder - works pretty well ! I had to fit a new lintel over a window and used this method suggested by a pal in the building trade, we also used the side cutting bit to remove mortar for re-pointing the brickwork.

As far as bricks are concerned there is a company close to me who manufacture many specialist bricks for all areas of the UK - maybe they can assist ? **LINK**

Hope this helps John

Rob, I have an Eclipse magnetic base purchased new by me and its close to 60 years old and in constant use so yes they live a long life !

John

Hi von dutch, Sorry been out all day but to answer the above -- no the lines don't have to line up exactly but its easier if they do [and simple with shim washers] - but if they don't you need to know and remember where to drop in the half nuts and of course it will alter depending on whether you are cutting right to left or vice versa.

Regarding the operating lever being maybe stiff or similar it certainly sounds as though some maintenance is required as GSCowboy suggests. I would remove the apron inspect the half nuts for damage or wear then clean and lube everything, amazing how much crud gets in there ! Also re-align the leadscrew as GSC says. The lever should move easily and smoothly.

John

First two questions 1 is your machine Imperial or metric 2 are you cutting imperial threads or metric ?

Do the lines on the rotating dial line up precisely with the mark on the body when the half nuts are fully engaged? If they are not you need to adjust this with washer’s on the mounting stud. Providing they do Line up you should start engaging just before, and I do mean just before, the chosen line comes up to the fiduciary line on the body. Lastly what speed are you running at? Higher speed makes it difficult up to almost impossible to facilitate engagement.

John

Its unlikely any local hardening would occur on car bodywork but it is possible it may happen on the mower blade - higher carbon content ! If this should happen you can resolve it by local heating with a propane torch, best to clean the area so its bright and heat until blue, cool as slow as possible. Not a full anneal or normalise but sufficient to allow filing etc.

John