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speedy
04-06-2006, 10:49 PM
I thought that I should post something other than quips, something relevant to this forum;)
I have my Colchester saddle and apron off the lathe. All the info that I have come across on this model says that it has an oil bath apron.... bollocks.
There is no oil in this one apart from what has got there by way of this poor example of oil distribution.
The oiler holes do not line up correctly with the oil gallerys in the apron.
The feed selector and surfacing shafts were not receiving oil to the gear bushes also the handwheel shaft was not getting good supply either. The bushings all have some wear; up to 0.01mm. Not a major IMO, just lucky that they are sintered?.
The gears rely on grease ( moly?)for lube.

What I intend to do is plug the oiler holes ( green)and redrill to better direct the oil flow to the apron gallerys (red). As they are, most of the oil spills to the inside of the apron and with the outer one, it barely delivers.
Look at how the apron witnesses to the saddle and you will see the poor oiling set up

Shafts that need oil are being drilled as is the gallery to enable better lube.

Make a manifold (blue) to distribute oil (or grease ) to the gears.
Put an oiler and drain plug in the wormbox.

grind an oilway to better distribute lube on the rear way( shear?).

There is some small wear evident on the saddle that bears on the rear way but it blues up Ok and there is only 0.05mm difference when measured with the shears and saddle. That is, h/stock to t/stock end, front and rear of the apron. Clear as mud??

What are your opinions or suggestions on these mods or am I wasting my time ...as it has lasted this long (35yrs) as it is?


Ken.

Are we able to post images direct to the forum? Photo bucket is tedious and when images are deleted from there they`re gone from this forum. bummer!
http://img.photobucket.com/albums/v367/speeedy/ColchesterMK2StudentApron025a.jpg
http://img.photobucket.com/albums/v367/speeedy/ColchesterMK2StudentApron020.jpg

agrip
04-06-2006, 11:25 PM
Speedy

I have a 17" Colchester of similar age.
A pump provided on the apron has been my only difficulty (known of). The pump was to deliver apron sump oil to the main ways, the cross slide and C/S screw and nut.

The front way felt seals leaked so badly that there was no way to get oil pressure to get oil to the rear ways. Pump vigorously for 10 min and nada.

I gave up and shop made a spl nozzle for a pump oil can that depressed the balls in the installed gits fittings, also sealed the input and allowed me to pump from the back way forward to front.
The same with the cross slide and screw.

If you have this rig, I suggest you do the same as I.
Otherwise I do believe that you should rig the apron lube so that it works appropriately.
If nothing else, you and the next guy will really appreciate the operation, and hey, it may be Hoffman.

HTH ag

speedy
04-06-2006, 11:45 PM
Yes agrip, this has a small sump with plugged sight glass aperture located to the lower left in the apron but no pump.It has never had one. It is all manual lube via the oil points (gits?) which is OK by me as it is just a home use unit.
How is your oil distributed? through drilled oilways or is it piped?
My main bitch about it is the poor oil distribution to the bushings and gears:mad: . My old asian Lantaine lathe had a better set up although no way was it as well built
Hey, its all an education... right?

J Tiers
04-07-2006, 01:36 AM
If you are not getting even distribution, you need to provide restrictors in teh lines, proportioned to the amount of oil needed at each area.

All "one-shot" type pump oiler systems I have seen use them. Otherwise the largest hole takes all the oil, no pressure to anything else.

The idea is to provide back pressure on all lines, and let the flow be according to orifice.

You can probably buy them from someone like Bijur, or make, if no good spot to put them in a copper line.

BTW, your pics have more than fixed the width problem...... :D

JPR
04-07-2006, 02:14 AM
I think your on the right track.

I had the same problem with the hand wheel shaft having extreme wear. During the rebuid, I installed two bushings instead of one with an oil passage between the two bushings.

This is a picture prior to grinding the pocket to help catch the oil. The oil passage is on the right side in the picture.

Before someone says something. The vise has home made aluminum soft jaws. This is not a way I recommend holding the front of the apron gear box, but was convient for installing and testing the fit of the shaft.

http://img.photobucket.com/albums/v228/jpr2004/Fronthalfofapronggearboxsmall.jpg

John Stevenson
04-07-2006, 05:18 AM
Don't bother Ken.
Just clean the lot up drill some drain holes in the bottom and fill it with grease.

I have repaired about 5 or 6 of these for local firms and they all have come in full of coolant which has displaced any oil in the box.
Some have been really bad, I mean really bad and spares costs have been over 1K.

It's a bad design as the earlier open apron model with the sliding engagement lever never wore like this one.
If you don't propose to ever run with coolant it would be worth doing but if you do the box, being sealed will just hold it.

speedy
04-07-2006, 05:25 AM
Thanks for the notes JT. JPR, I am lucky that wear is minimal on the shafts, bushes and gears although it is all cumulative but what is a bit of lash eh? An extra 5 degree on the handwheel?..no problems.:p

Yeah, the pics are a wee bit wide aren`t they. I`m proud of them though, I just worked out how to scribble all over them with words and such, wha hoo!; I learn quick don`t I ? ha ha .

I am thinking that I will make a copper pipe distribution manifold that will roughly follow the blue route, it will have drilled tags welded to secure it to the saddle. I have yet to decide where the new oil entry point will be though.
I figure to drill small holes at points that will enable accurate and even application to all gears and "bench test" before final fitment.
In this instance I prefer manual oiling, there is only the single machine and I trust my oil can .
Worse things could have been revealed if it had been an oil immersed apron..rusty corroded gears. Nowdays I try to count my blessings:)

Jeez, I`m a slow typist. You got in there before I posted John.
This apron is not enclosed, it is the open type with a pivoting wormbox. Here is a clearer shot to better illustrate. I have considered using grease again but there is an amount of stray metal that gets into the wormbox and could transfer into the apron gears. I like the washing of grit that oil does? What do you reckon, still grease?

Ken
http://img.photobucket.com/albums/v367/speeedy/ColchesterMK2StudentApron001.jpg
http://img.photobucket.com/albums/v367/speeedy/ColchesterMK2StudentApron003.jpg

John Stevenson
04-07-2006, 07:03 AM
Sorry, thought it was the enclosed type where the lead and feedscrew run thru the ends of the apron

speedy
04-07-2006, 07:36 AM
No worries John; do you have any words of advise to assist. All help and criticism accepted:D
And I have substituted the correct other image...oops

Ken