TDS1/1GB lathe new owner advice

[Kenk]

I have just become the proud owner of a Denford Viceroy lathe and would like to ask a couple of questions.

I can't seem to engage the feed or lead screws using the leever on top of the gearbox, is there a certain procedure? I am trying with the machine running as it says.

Gearbox oil seems a bit low, can someone recommend the correct oil?

Many thanks for any advice

Ken

[LesT]

Hi,
Its a bit difficult to fault find over the internet I'm afraid !.
I take it you have a drive set up under the rear guard ?
I take it you have the sliding hi/low selector gear set to one or the other ?
I take it you have selected a gearbox ratio ?
I take it both the feed shaft and leadscrew are free to turn, not siezed/jammed.

Don't forget you can just turn the input shaft by hand and try the selector levers.
There are also a couple of shear pins I think.

[Kenk]

Thanks

I have checked and can answer yes to all these questions.

Turning the input shaft by hand and moving the feed screw/leadscrew does appear to engage a gear. The feed or leadscrew will now turn as I turn the input shaft, if I grip the feed or leadscrew however ( depending on which I have engaged) I can stop it turning. I am guessing therefore the shear pins referred to have sheared.

Can anyone therefore give me any more information on the shear pins? Where are they located? What are they made of? And ideally how do I fix them?

Thanks again
Ken

[LesT]

Hi,

If you have a look at this topic there are some scans of various drawings.
(cut and paste into your browser)
viewtopic.php?f=50&t=2986
(This is a sticky from the Index page)
One of the drawings ML115/100A shows a shear pin on the drive system, its located on the final drive
into the gearbox, under the end cover.
There are also other pins of different kinds, which although not shear pins as such, could concievably be sheared located within the gearbox.
I'm hoping its a shearpin problem !

Les.T.

[Kenk]

Brilliant!! Exactly right.

I have drifted the broken pin out with a drill bit (don't have a drift small enough and drill bit was bang on!)

I have never replaced a shear pin before, can you buy such a thing? Or what should I make it from?

Very many thanks

Ken

[LesT]

Hi,

If you look through the parts lists you might find a description and material.
On the other hand you could choose a material yourself.
Aluminium - soft, easy shear.
Brass- medium
Steel- hard.

What was the old one made of ?

PS, I would be a bit worried if the shear pin failed, check gearbox oil level etc.
Make sure shafts are free to turn and are greased.

[Pete.]

Most common way to shear the shear pin is to run the cross-feed out under power until it stops against the dial housing.
I would just make one from mild steel. 1/8 or 3.175mm diameter. You could use silver steel but don't use a drill bit or roll pin as they won't shear so easy and might bust something expensive instead.

[Kenk]

Many thanks for the advice chaps, all working ok now.

One further thing I have found now is when using feedshaft to drive longtitudonally the movement stops every so often ( feedshaft still turning fine) if I then "encourage" things slightly using the hand wheel it all starts driving again.

[Pete.]

Sounds like you have a broken tooth on one of the apron gears. Might be related to the reason for the sheared pin.

[Kenk]

Just got round to having a further look at this. Again appears that you are correct. On the apron arrangement drawing, part number ML110 309, worm gear, has at least two broken teeth.

I appreciate spares are no longer available and gear cutting is way beyond my abilities! Anyone have any suggestions?

Thanks again

Ken

[Pete.]

I would start by calling Bede tools and machinery, as i recall they have broken a couple of these.

https://www.bedetools.com/index.html

[Kenk]

Unfortunately they don't have the worm gear. Any other suggestions?

Thanks

[dazz]

Hi
If you can't make one, get one made. It won't be cheap but it will restore a very useful feature of the lathe.