Member postings for Lambton

Best of all no blasted background music!

pgk pgk,

Getting back to your original question.

If you want to have gears with properly formed teeth using involute cutters then you must use the correct cutter for the number of teeth required. Involute cutters are sold in sets of cutters for cutting the whole range of gears from 12 teeth to rack. If it were possible to cut all numbers of teeth properly using just one involute cutter as you suggest then there would be no need for the set of eight. This would imply that all makers and users of sets of involute cutters are wrong and have been for years. Clearly not so.

A simple solution is often to make a single tooth cutter to the profile of the nearest gear that you have or use Ivan Laws “button method”. I made a 26 tooth change wheel for my Myford lathe using the 25 tooth standard gear as template for the single tooth cutter.

If the application is for a low speed, low load application then a certain amount of licence can be taken in producing a gear tooth form. For example a change wheel for a lathe. However if the gear is to be used at high rpm and transmit power for long periods as in a vehicle gearbox then the forms must be spot on then the gears will run quietly, absorb minimum power and have along life.

Have look at Len Mason’s excellent book Using the Small Lathe which explains simply about cutting gears in chapter 16.

Graham,

How are you mounting the dial gauge?

It is very easy to flex or displace slender mounting rods , clamping joints, magnetic base etc. without realising it.

Try mounting your "inaccurate" gauge as rigidly as possible over a surface plate, or even the mill table, then test it against metal blocks previously measured for thickness using a good micrometer. If you have some slip gauges then so much the better. Carefully done this test will quickly show if the dial gauge is good or bad.

Eric

Graham,

Are you sure the axis of the DTI plunger is exactly aligned with the table axis. If it is not accurately aligned in this way the reading will always be too high.

Martin,

My lathe has a power cross feed and I "jammed" the pinion against the lathe bed as described.

Other advantages of the Meek handle is that being on the saddle is very easy to see whilst the work is in progress unlike the lead screw hand wheel dial (virtually impossible on a long bed lathe). Also it works all the time with no need to engage the half nuts.

Eric

Martin,

No need to dismantle the apron.
Make a drill bush with an 3.3mm though hole and a concentric blind hole that is a nice fit on the pinion shaft - No need to make any form of locking provision.

Lock the saddle to the bed to prevent the pinion turning then make a short piece of wood to fit tightly between the end of the pinion and the lathe bed just below to rack to prevent the pinion moving back.

Drill the 3.3mm end hole with a normal battery drill tap the hole and the job is a "good un".

Hope this is of help.

Eric

Piero,

You are making a fantastic job of refurbishing your Super 7.

You should fully assemble the lathe and run it a while to ensure everything is bedded before you "level" it. If you attempt to level it too early you will only have to do through the procedure again later.

Eric

Martin,

I fitted one of these to my imperial Super 7 with PCF about two years ago. It is without doubt the most useful accessory I have bought or made for my lathe. It is very accurate and most convenient to use. Fitting is a doddle and removing it periodically to put oil into the apron takes about 5 minutes.

Either cast iron or bronze will be fine for the sheaves. Phosphor bronze is not necessary unless you have some in stock.

If you use black mild steel for the strap take care to get the good accurate finish where it runs against the sheave.

It is important to have the front bronze bush secure so I suggest that you remove it clean up the surfaces and use some suitable Loctite to secure it. You will need to hold the bush in the fully back position until the Loctite sets completely - Use a length of studding and some large washers for example to hold it in firmly. Then readjust the preload on the back to back ball races EXACTLY as per the Myford instructions. When the Loctite has set reinstall the spindle taking great care to get the minute clearance necessary between the spindle ant the front bush by adjusting the ball races as a "locked together pair". In my experience you should not see much, if any, oil emerging from the front bush during normal use IF the clearance is set correctly.

Eric

His name is John and is referred to a "Doubleboost" start by looking a setting a 4jaw chuck which is very easy to understand.

Curtis,

Have got a copy of the official Myford handbook for your particular model? They can be downloaded for free as PDFs

Sparey's book is very good but rather dated only really covering the original ML7 with nothing about the Super 7 or ML10 models which did not exist when the book was written.

Ian Bradley's Myford series & Manual is very good and covers the Super well.

Probably the best introduction to turning for beginner's is Using the Small Lathe by Len Mason - nothing about Myford lathes but good step -by- step details and instruction about getting the best from any small lathe.

Look on YouTube for videos by the Geordie with a Boxford I cannot recall his name but he is spot on with his advice and is very entertaining.

On a small lathe cutting aluminium I think VCR would be better advised to use a really sharp HSS tool ground to the appropriate shape with paraffin as a lubricant.

VCR,

You are probably using the wrong shaped tool. Try one that has a "flat" behind the cutting edge that follows along the required shape. Hand to explain but is a type of cutter recommended for fine finish on many materials.

mrbuilder,

Well I am surprised! I sincerely hope that this holder gives you good service.

mrbuilder,

I am not familiar with Bison tool holders and would be very surprised if had such a severe sharp undercut as the one illustrated. If they do then I hope Bison do not make any safety critical components!

Avoiding sharp corners is elementary engineering practice. There have been many catastrophic failures of structures over the years caused when this principle has been ignored.

It is simply bad engineering practice that creates a classic "notch" that will certainly induce a fracture sooner or later.

Avoid tool holders with this feature.

Dusty,

"turn a chamfer on the gears so missing the adjuster "

Do NOT do this - as you say it should not be needed.
Assuming the problem did not exist before you removed the spindle then clearly you have not put things back quite right. I guess the split collar is now too far to the rear. Please read the Myford instructions again and ensure you do things in the correct order. It is easy to upset the rear positions of the rear bearings when removing the spindle so always attend to getting the preload on them correct first by adjusting the split collar. Then attend to the front bronze bush settings.

Eric

Wolfie asked a simple question because he wanted to know the answer - rather than just guessing or making an assumption. This is what we should all be prepared to do as no one knows all the answers even to seemingly simple questions.

My late Father, an expert tool maker, told me to always ask about things or instructions that I did not properly understand. I told him that I feared appearing foolish by asking such questions. He replied that no one worth listening to would think me foolish but I would look really foolish if I guessed the answer and made something wrong wasting valuable materials and time in doing so.

Ask away Wolfie and anyone else who has a seemingly simple question.

Nick,

For many years I have used a Reliance drill grinding jig in conjunction with a normal off-hand grinder. It produces as

perfect result every time (if set up carefully). Sadly Reliance have long been out of business however Hemmingway supply a kit for making an almost identical jig.