Member postings for Leszek Delag

Many thanks for all your help and advice everyone. Very much appreciated!

A bit of a dilemma here..

..and would much appreciate some expert advice. I have some small machined-not cast-aluminium components which have at some stage been black anodised where they ought to have been black painted. I would like the appearance to be as authentic as possible and am considering spray painting them with a rattle can. The problem is that I have had diametrically opposing views about this. On the one side, the view is that paint adheres very poorly to anodised aluminium and this should firstly be removed by bead blasting, then acid etched first. The second camp says with some authority, that anodising is the best possible base for painting, providing it is washed scrupulously clean first..

I am a bit loth to subject these parts to bead blasting as they are a bit fragile now so can I please ask for the considered opinion of someone experienced in this? The other point is that a the assembled item will spend a good deal-but not all-of the time outdoors.

Thanking you in advance.

Many, many thanks for all your kind replies everyone..it is so much appreciated!

Because of the nature of it, I have to use flat section instead of round-which would be so much easier! The loop wraps around a pivot and it lifts quite a substantial weight.

Am following up all the suggested sources and sending you a pm Adam-thank you.

Kind regards and thank you again..Leszek

Hello all, I have to replace a broken lever spring on a mechanism and am trying to find a suitable source of material. The spring steel is bent something like a “V” with a loop at the bottom to go around a dowel, is flat in section, measuring about 3/32” x 0.044” having a total length of approximately 4” when opened out. The section size is not vital, providing it is reasonably near and if anyone could point me in the direction of a possible source of material-preferably in the annealed state- I would be most grateful!

Thanking you all in advance.

I also have an external thread cutting tool with carbide inserts and from my own limited experience have found that these are not really suitable for non-CNC lathes. You are quite right about ‘fast’ but not about ‘hard’, though doubtless those more experienced will have found a way.. If your tool inserts are of full external thread form, they are best used by applying the cut down half of the included angle, using multiple, equal cuts at high speed. For say 1/2” diameter BSF threads, you would need about 20 passes or more at about 750 rpm with coolant to prevent the metal tearing and giving a rough finish. The big problem will be with leadscrew disengagement at high speed. Cutting into a shoulder might be courting disaster! If there is a big enough area beyond the threaded part, to give you a safe disengagement, these tools are fine, but you really have to be on the ball when using them manually. Sorry I cannot be of more help.

I have just finished a job in PB102 bronze on my Myford and in which I needed to tap 39 (thirty nine) M1.4 holes 3/16" deep. To be honest, it is not as difficult as it sounds. The most important thing is to start by centring lightly with a No.0 centre drill and use a new, high quality HSS drill. 1.1mm dia. is good for brass over a short length but, despite what the book says, you can get away with using a 1.2mm drill instead of 1.1mm for bronze. There will not be quite as much thread but they are strong enough for purpose. I have been told that 75% thread depth is still 95% efficient, so you are not losing much strength anyway.

It is also much better to never cut dry, always use a cutting oil and "3-in-1" with added PTFE will do the job for you. I drilled at about 800 rpm, with light cuts, relieving the drill frequently and tapped by hand, relieving the tap every two turns.

I have never tapped this small a size before but did all 39 holes with the same drill and the same tap and don't think you will have any problems either.

Kind regards,

Leszek

Many thanks to all for your reading recommendations..

I think the best plan will be to now make a good study of everything first and see what the best practical design will be after that.

Thank you all once again.

Hello all,

Please don't throw up your hands in horror but I have always liked small engines ever since owning a basic, horizontal boilered Mamod model, just post war and would now like to design and make my own, entirely from scratch.

My 'workshop' equipment to date, consists of a 1954 Myford (rather worn) for which I have recently bought an 'Amolco' milling attachment. I also have a 1967 electric drill stand, a small surface plate, sundry tools and drills and a 'Turbo 90' brazing torch.

I do realize that live steam-particularly if superheated-is not something to fool around with nor ever to be taken lightly, nevertheless, would like to have a try. Some 20 years ago I rescued two pieces of thrown out tubing and feel that one of these might well be made into a steam boiler. The first piece is from a pneumatic cylinder, of seamless brass, 18" long, 2.750" outside diameter with a wall thickness of 0.125". The second piece is seamless copper tube, 8" long, 3.125" outside diameter with a wall thickness of 0.070".

I also have several lengths of 316 Stainless tubing, 0.250" o/d of substantial wall thickness which might possibly become boiler tubing..

I do not know very much about the various gauges , valves and water injector needed for boiler construction so would greatly appreciate some solid advice and guidance, particularly if you could recommend a good book explaining what everything does and all what would be needed for small boiler design.

I have not considered the cylinder layout yet, but am inclined toward a horizontal single. The important thing is to first design and build the actual pressure vessel-the boiler-and so all practical reading and advice you can give will be greatly appreciated.

Thanking you in advance,

Leszek

Many thanks Robbo..I figured that this would be the way to go..

Having looked around, the cost of a set of genuine Myford collets-which have to be in very good condition for the work I intend to do-would probably cost more than I paid for the machine..if you could get them!!

I have ordered a set of MT2 collets from Germany. They cost £55.56 for the five, 4mm to 12mm, but seem to be good quality. They have an M10 thread so I am thinking of turning down a length of M10 studding where it has to pass through the top, then thread that end M8 or 5/16" and make a screw-on knurled hand wheel and spacer for the top.

It ought to do the job and wouldn't be to much bother to detach when not required.

Thanks again for the advice..

Leszek

Edited By Leszek Delag on 08/07/2018 22:48:02

By coincidence, I have just done this job!

Commonsense suggests that there should indeed be a soft pad in front of the screw-which is 3/8" x 20 BSF, by the way. Instead of just an socket head screw, I made mine as a ball-ended lever. The end of the screw was drilled out to 3/16" dia. x 0.2" deep and a 3/8" dia. piece of brass with a 3/16" dia. spigot on the end pressed in. The brass was turned down to 0.3" afterwards with a good chamfer on the front. The length of the brass pad was then adjusted until the lever locked on when about horizontal. It now pinches up quite nicely without faffing about with Allen keys and safe in the knowledge that you won't damage the column or get the brass pad stuck inside.

With regards..

Edited By Neil Wyatt on 08/07/2018 22:48:52

Firstly, thank you all very much indeed for your most informative replies...they are very much appreciated indeed!

I have been working on the Amolco attachment today, rewiring the motor electrics with correct and undamaged cable and replacing the existing cracked domestic light switch with an NVR switch. Have discovered that the nose thread is 1 1/8" BSW, the same as that on the Myford spindle. The internal thread is definitely MT2 but the spindle bore at the top is only 5/16" so I would imagine that I will have to make a custom drawbar for any collets I buy?

Many thanks Emgee for your observations re. an ER collet head taking up a lot of space..a very good point that as as everything is much more stable when the cutter is close to the spindle end. I already have a nice Albrecht keyless chuck with a No.2 Morse taper, which will hold drills from 3-13mm and feel that MT2 collets will be the best option as the biggest milling cutters I own have a 12mm shank. There is a German company on a well-known website offering a small set of precision MT2 collets from 4mm to 12mm for a fairly reasonable sum and they should cover most things that I intend to make.

Re. bearing replacement, point also taken about cheap bearings..I am looking at SKF ones at present but there is a question mark over the size..

There is a long way to go before the attachment will be usable.. I discovered today also, that the motor pulley block had been hammered on..! I eventually got it free with the aid of a custom 3-point puller, but the bore was so dreadfully scored up that I have had to bore it out in the 4-jaw on the lathe, sleeve it and rebore it out to size again. Have also removed a good few of the dents to the block and got it running true and concentric again.

I just don't understand how some folks can spend good money on nice machinery and then abuse it so much..

Will try and post a photo when it is finally operational again! Many thanks once again for your help.

Kind regards,

Leszek

Hello all,

I recently bought an AMOLCO milling attachment online for my old Myford. It was in fact, in very poor shape all round on inspection after arrival, having had a very rough life and been poorly treated, but am gradually getting it back to running condition.

The spindle has an internal MT2 taper and an externally threaded nose. I would like to buy a collet set for it but am a bit confused by the many choices of size; ER20, ER25, ER32 etc.

The work I intend to do is to fine tolerances and I would be very grateful if anyone out there could offer some sound, practical advice and guidance to a beginner please..Also, is it possible to still buy the tapered bearings for this attachment as the existing ones are running very noisily.

With many thanks in advance..

Have just joined and this is my first post! I have a very early S7 which was bought as virtual scrap and have managed to get it working again fairly well, but the clutch has always caused headaches and it was whilst seeking answers that I discovered this place. My lathe previously had a very rough life and was horrendously abused. The cast iron plate with the two 1/4”BSF grubscrews at 90 degs. on the right hand side of the countershaft had been smashed with a hard hammer and broken and the grub screw clutch adjuster broken off inside. After considerable difficulty I managed to wiggle the broken screw out and managed to drift out the countershaft-which has been damaged. I have stoned off the swelled high spots from the shaft so that it is serviceable but amtrying to locate a new one. If anyone anywhere knows of anything remotely serviceable, I would be most grateful! I have now remade the lathe so that it is running again but off up to you some of the modifications I have done. Firstly, some of the needle rollers were missing from he right hand bearing. I have cut lengths of 3/32” silver steel as substitutes and spaced them between the genuine rollers. Secondly, I have made 0.752” bore spacers to fit the gaps each side of theconed clutch pulley cluster. The left side is 0.195”thick and the right-0.300” thick. This seemed to prevent heavy lubrication loss from the bearings. The last modification was to make a new clutch adjusting grubscrews but drill the end and press in a 5/32” ball bearingto improve smooth operation. Hope this meets with your approval..