# I stole a lathe!!!



## Holt

Last weekend i went to see an old Danish machine company lathe, it was missing quite a few parts http://www.homemodelenginemachinist.com/index.php?topic=17615.0 this week i have been thinking if it was worth the effort and money to restore it. meanwhile i was searching the web for another lathe, and suddenly yesterday afternoon a new advert came up "Good and old lathe for sale, motor dismounted, otherwise in working condition $580" (well the price was in Danish Kroner but i exchanged it to USD) i went to see it today,and it turned up to be a Colchester / Clausing Triumph 7 1/2 x 48 (15 x 48 in the states) a bit rusty on the bedways, but nothing a bit of TLC (and some new bearings in the motor) wont cure, it have lived in a tractor and machine shop, and have never done production work. I bought it on the spot, and are going to collect it on Saturday







This sketch from lathes.co.uk shows how it looked like once,
And here is what it looks like today





I am going to make some modifications, i will post it as i go along


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## Peter.

Nice score. I bet it will clean up just great.


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## steamer

that's a better direction I think!

the money is short.....

Dave


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## arnoldb

Thm: That *IS* a nice score Holt

 ;D Guess you'll have to bring out the elbow grease soon to clean it up!

Kind regards, Arnold


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## willburrrr2003

Nice, a beautiful old machine you have there!! I will follow it's restoration with definite interest 

Regards,

  Will


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## metalmad

Nice one buddy
Pete


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## bronson

I look watching old lathes get cleaned up. Good find hope it works great for you.

Bronson


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## Holt

I do think it was a good score,and i can't wait to get it into my little workshop and start cleaning it up, i only paid a little bit more than the asking price on the Danish Machine Company lathe, but this one is in a whole other league,and cant be compared in any way.
 what should i do with the paint, once i have it cleaned, on a car, i would wax it, but do i do that on a lathe, or are there other tricks to keep it from attracting dirt like a magnet?

Holt


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## n4zou

Holt  said:
			
		

> what should i do with the paint, once i have it cleaned, on a car, i would wax it, but do i do that on a lathe, or are there other tricks to keep it from attracting dirt like a magnet?


Don't do anything to the paint except to wash it with soap and water. That lathe is painted with lead paint. The only way that paint can harm you is if you eat it or start sanding or grinding on it to remove it for a new paint job. For me an old lathe should look like an old lathe in it's original paint. It took many years to bring out that patina and you should cherish it. If you do remove the paint do it when chemicals so you don't end up with lead dust everywhere.
If you are going to let it sit for long periods of time cover it with duck canvas which will keep dust from collecting on it. *Don't use a plastic cover!* Plastic will hold moisture which will collect on the lathe and cause moisture problems. The cover needs to breathe. Before you throw the canvas over it coat all bare metal surfaces like the bed ways with grease. This will keep them from rusting.


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## steamer

YUp it's a good bet the paint is lead based. Chemical stripping is an option....as is giving it a good chemical cleaning and painting right over it! ;D

Dave


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## DennisWA

Holt

I wish you luck in your project! 

I have a Colchester Student and have found the Colchester user group on Yahoo useful - see: 
http://groups.yahoo.com/group/ColchesterLathe-User/

I do not know your expertise in rebuilding machine tools, but there is a lot of information available on Colchester on other internet forums in addition to the user group and Tony's Lathes.co.UK site. 

Dennis


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## Holt

Thank you all for your comments and advices, and thanks to you Dennis for the link, i will surely be joining when i have the home ready for the new one.

I have been working with lathes for 30+ years, and done maintenance and small repairs, but never done complete overhaul. I have access to a range of different machines, mostly cnc mills, i could in fact place the whole lathe on the bed of one of our large mills ;D

One of the first modifications, once the mill is in working order, will be a QCTP, and some tool holders.

Another one will be a DRO, i have a rotary encoder for the main slide, and an Heidenhain glass scale for the cross slide.
I need to convert the sine wave signal from the glass scale to a square wave TTL signal, but it don't seem, that anyone knows how to build an inverter, i might have to buy an Heidenhain interpolation box

Holt


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## Noitoen

Holt  said:
			
		

> I need to convert the sine wave signal from the glass scale to a square wave TTL signal, but it don't seem, that anyone knows how to build an inverter, i might have to buy an Heidenhain interpolation box



It's not so difficult to convert the sine/cosine output to square wave. The cheap magnetic scales use this method because the N/S poles are spaced exactly 0,5mm. apart. You need a little amplifier to shift the sine/cosine wave centred on 2,5V so that the top peak goes around 4,8V and the bottom around 0,2V. Since the 2 outputs from the encoder are "shifted" 90º apart, a simple microcontroller with a pair of 10 bit analogue inputs can easily calculate a resolution of 0,005mm and generate a pair of square waves.

I have somewhere a schematic for this amplifier I can look for if you are interested. I still haven't got to the microcontroller's final stage since I plan to build the complete display but I've tested the "proof of concept" and it works.


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## Holt

I am very interested in your schematic, i have been searching the net, but only found out that it should be a Schmitt trigger to avoid electric noise. I have been working with electronics at repair basis, not as developer, however i can make PCB's. and solder components.
I will try to use the Mach3 cnc program for the DRO, maybe a little overkill, but the program is free, when you limit it to 500 lines of G codes, and i won't be using any G codes for the DRO ;D


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## coopertje

Congratulations Holt! Seems like a very good and rigid machine you got there. And there is no greater satisfaction to finally work pieces on a machine that you have overhauled!

Have fun with it and hope to see your progress on the machine over here, I will be following along for sure.

Regards Jeroen


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## Holt

Well, the lathe are in the workshop, and have been for a couple of days, it was too wide to enter the door, so i had to remove the doorframe :-\ 






Here it is loaded on the trailer, this is NOT a normal Brenderup autotrailer, but a modified one with a reinforced middle section, so it was safe to roll the lathe off with two pallet lifters (or whatever they are called)






Here it is passing the first obstruction, a 14 cm high edge, normally here is a ramp, but it cant take the weight of the lathe






these machine skates is Gods gift to people moving heavy loads, a lathe can be moved with one hand on these things






This jack isn't bad to have either






At last! It's in the workshop, ready to a overhaul, i think i will start with mounting the doorframe and door, it's going to freeze tonight


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## steamer

woohoo1 woohoo1


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## dalem9

To keep things from rusting I mix about 6 parts wd40 with any 1 part of oil , then spray it on . It will leive a thin coat of oil after the wd40 dries . Hope this helpes . Dale


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## CMS

Nice lathe score, but I think that I like the big MF's in the background just as much.

Craig


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## lathe nut

WOW, great looking lathe, always room for a lathe and such a great deal, more lathes the better, will be looking, Lathe Nut


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## Holt

CMS  said:
			
		

> Nice lathe score, but I think that I like the big MF's in the background just as much. Craig


We tried, but we couldn't have them on the trailer ;D

I got another bargain the other night, a heidenhain interpolation box on eBay Germany, winning bit 12,50 EUR or about 16 USD


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## Holt

It's been a while since last update, i started with removing the rust from the bedways, it was easier than i had feared, then i removed the cover of the headstock, to find out there was very little oil, and a lot of molycote grease


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## Holt

I took the middle shaft of the gearbox out to gain access to the bottom, i removed all grease and oil, and found out the seals (drive shaft and tumbler shaft) was very hard, and one were cracked, and that one was under normal oil level, no wonder they couldn't keep the oil in.
I bought new seals and o-rings for the entire gearbox, but being in a metric part of the world, i had to buy metric seals, i found some that required very little altering to fit.
When i cleaned the shaft and gears, i discovered one of the gears was loose on the shaft, the key and keyway was worn so that the gear could turn a couple of degrees, i bet that would be noisy when making interfered cuts!


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## Holt

I made a wider slot in the shaft, and a wider key was turned and grinded, the gear wasn't worn, so i milled the top side of the key to fit the gear.


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## Holt

My son cleaned up the frame, and that transformed the look quite a deal






it's beginning to look usable






Holt


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## Holt

according to the old manual i found on the Colchester user group on Yahoo, the sattle belongs to a Dominion while the rest is a Triumph, but i doubt it have ever been changed






The triumph should have T slots, and the main handle in the other end


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## Swede

Looking much better! That spindle nose is a bit different... is tooling going to be readily available?


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## DennisWA

The spindle taper is American-type long-taper key drive size L1 and backplates and 2nd hand collet chucks are still available, in both UK and USA. (I'm not sure about Denmark).

There is lots of information on the lathes UK site:
http://www.lathes.co.uk/colchester/page8.html

The reason for this Triumph having a different saddle/apron is that it is not a gap-bed model and was sold as a "Dominion" model as Holt has found out. The handwheel is on the left side of the carriage and not on the right side as in gap-bed models, which have T-slots in the saddle wings.

Well done Holt with your progress so far! 

Dennis


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## maverick

Great score on the lathe. The spindle looks to be a L00 type, Same as my Delta-Rockwell 11 inch. Back plates and 
 complete chucks are available here in the states, not sure about your locale.

 Regards,
 Mike


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## Holt

The spindle nose is American long taper size L1, i have a back plate on my 3 jaw, and a spare one






Dennis - you postet while i was writing

Holt


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## Holt

DennisWA  said:
			
		

> The reason for this Triumph having a different saddle/apron is that it is not a gap-bed model and was sold as a "Dominion" model as Holt has found out. The handwheel is on the left side of the carriage and not on the right side as in gap-bed models, which have T-slots in the saddle wings.
> Dennis


I don't think this is a Dominion, because that version didn't have metric treating, this one have 

Holt


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## DennisWA

Holt..You are right - I was wrong to call it a "Dominion", as it has the Continental gearbox (see below). 

The saddle on your machine is what Colchester fitted to non-gap bed machines. If I read the literature correctly it appears that the majority of these lathes had gap beds. I am happy to be corrected by any of the knowledgable Colchester folk! 

*Lathe UK quotes*:
Later models, probably coinciding with the introduction of the Mk. 2 in 1964, had a choice of three different gearboxes (Standard, Continental and Dominion) and, for the first time, a metric pitch leadscrew: the Standard was an improved dual English/metric unit run in conjunction with an inch-pitch leadscrew and gave 45 English pitches from 120 t.p.i. to 4 t.p.i. and 12 metric from 0,25mm to 6mm; the Continental was combined with a 6mm pitch leadscrew and generated 31 metric pitches from 0.3mm to 12mm, 32 English piches from 2.5 to 60 t.p.i. and 16 Module pitches from 0.3mm to 3.0mm. The Dominion gearbox, as before, produced only English threads but this time with the number increased to 45 and the range set from 4 to 112 t.p.i..


Dennis


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## thissentenceisfalse

Not to interrupt the flow of conversation, but I believe mine is a dominion type saddle? Colchester 12"

Nice to see more of these great older lathes!


Anthony


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## Holt

Nice looking student you got there, it looks like the Dominion type sattle, with the handwheel in the left side. Doesn't the student have feed on the cross slide? no metric treating? I would have preferred a lathe this size, because of the limited space in my workshop, but the triumph was what i could afford, a student in worse condition as my triumph, is up for sale for 2½ times the price of mine


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## thissentenceisfalse

The gearbox says dominion on it, but the base says student on it. Im pretty sure its the student package though. Power feed on the carriage and the cross slide, standard compound slide. Everything is in English measurements and all English threads. What do you think mine is worth? I got it through a deal with a cousin, he cant/doesnt have time to use it or have room so I fixed it up a little bit and got it running. It has a decent amount of wear on it, does need to be gone through. I really like the lathe and am going to, at some point, quit mooching and offer him up on it. I think he paid something to the tune of a few hundred US dollars for it at a closing graphite/carbon factory.

Anthony


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## Holt

The price on your lathe depends on supply and demand in your area, here a lathe like this, would likely be sold for 1500-2000 USD if in reasonable condition. Its a very desirable size, small enough to fit most workshops, and large enough to turn "real" stuff

Holt


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## Holt

The sattle is off to be cleaned underneath






The oil channels on the apron was filled with dirt, and no oil could ever find the way to where it should work






There are seven oilers in the sattle, and i made nine, that means i am able to put it all together, once i get the oilers finished






Holt


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## Holt

Two old and two new oilers, if anyone needs it, i could make a quick sketch of them






Now there are oil in the headstock, and it seems like it is staying there, at least i haven't seen any leaks by now, the oil has been in for a week!






The motor is mounted and it spins! The headstock is a bit noisy, but not more than expected on a 54 years old lathe with straight cut gears.
 The brake works surprisingly well, neither pads or drum shows any signs of wear


Holt


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## Holt

The reason i wanted that design on the oilers is that i have this Swiss made Wanner high pressure oil gun. It don't look like much, but it really can pump the oil to where it is needed.
The manufacture claims it can deliver 150 bar of pressure, that's 2175 psi! I guess it depends on the weight of the user ;D






Holt


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## Holt

Reading various posts about machinery this size on this forum, it seems many of you use phase inverters. Isn't it normal for you to have 3 phase power? my guess is that over 99% of the houses in Denmark have 3 phase power.
By the pavement, there is what they call a "tombstone" with 3 35A fuses in front of the cable to the house. In the house it is normally split in 10A 230V groups for lightning and wall outlets, 16A 400V groups for washing machines stoves etc. (and of course in the workshop ;D )


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## steamer

Hi Holt,

Most homes inthe US have single phase, 120V,and 220V single phase 60 HZ.

Getting 3 phase in from the street can be very expensive unless you can justify it for a business....though it is usually there on the pole.

Our power is distributed at a much higher voltage than this, and then stepped down with pole mount transformers at the point of use.

Dave


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## Holt

The distribution net here is of course also much higher voltage, the local distribution is 10.000V the regional distribution is 60.000V and cross contry is 150.000V, and then there is the "Backbone of Europe" running a few kilometers from me, running from Italy to Norway, where the country's can buy and sell power as needed it's 400.000V


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## n4zou

steamer  said:
			
		

> Hi Holt,
> 
> Most homes inthe US have single phase, 120V,and 220V single phase 60 HZ.
> 
> Getting 3 phase in from the street can be very expensive unless you can justify it for a business....though it is usually there on the pole.
> 
> Our power is distributed at a much higher voltage than this, and then stepped down with pole mount transformers at the point of use.
> 
> Dave



Here in the USA you must pay for the installation cost including cables, poles, and distribution equipment. You also must pay for it before they will install it. Then you must pay the commercial rate which is much higher than residential rates. 3-Phase power is not available on all distribution lines. Typically only single phase distribution lines will be run into residential and rural areas.


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## Holt

I serious need some help! I found the guide for the halfnut to the leadscrew is broken, and i have to remove the leadscrew to get to it. I have removed the two nuts and the bush by the gearbox







Then i tried to remove the key, it moves, but it wont come off. I drilled and tapped a hole in the key and attacked it with the crowbar, and the winner of the battle  the key!! I don't know if it is necessary to remove that key in order to remove the leadscrew, but i am kind of stuck until some clever people tells me what to do, what am i missing here?

Holt


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## steamer

Hi Holt,

I think the key is to drive the thrust collar.  I "think" is should come out of the gearbox without removing it.

Have you been able to find a assembly diagram for the lathe?

From what I can see of the photo, it would appear that the lever on the front of the box engages the leadscrew. That means the collar on the inside has to come off to pull the leadscrew? from the box?

Don't use a crowbar....if it needs that much force , I would be afraid your missing something....you should get a diagram of the box first.

Dave


Dave


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## Holt

The trust at the inside, and the treaded area are one bush, and the leadscrew goes all the way through it, the two gears in the picture runs on the leadscrew.

Holt


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## steamer

Hi Holt,

I poked around looking for a manual online for that vintage lathe, and I didn't find one right away. I did find one for a more modern Triumph, but it would appear on the more modern lathe to have shear pins located at the intersection where your keyway is.  There was also a retaining ring.....I would look very carefully and see if there is a retaining ring of some sort.

Dave


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## Holt

I have a download of an old manual, but it is a bit blurry, so i can't see it clearly. the shear pin is located at the exit of the headstock. i am afraid it once had an accident with the leadscrew, perhaps the key is partly sheared leaving it almost impossible to remove. It seems there is treats under the grub screw, which means the lead screw should be unscrewed from the bush, and that's only possible if the key is removed (Sorry if my explanation is a little vague, its clearly that English isn't my native language)






Sorry for the lousy hands on the pic. seems photobucket changed the edit function, and i can't figure out how to use them. much easier before


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## steamer

OK  is the grub screw a double screw?  Often times a grub screw is backed up by another one.  You should check...

Dave


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## Holt

No it's not a double screw, now that i have fixed the small Maglite, i can see the treats in the hole,and the leadscrew rotates a little in the trust sleeve (as i learned it was named) but not more than the key allows.

Holt


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## steamer

Hi Holt,

I would look for a pin.  It would be very difficult to thread a key into a blind keyway surrounded by a thread.  The schematic I saw had a shear pin.....I would look very carefully.....


We're still missing something here.....


Dave


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## Holt

I got it apart!! It turned out that the grub screw didn't screw into the trust sleeve as i thought, but into a loose disc that looked like a part of the trust sleeve. Once i screwed that off, the leadscrew slided right off.
Dave, thank you very much for your help

Holt


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## steamer

Ha!  knew it was something! ;D

Lot's of pictures please!
 ;D

Dave


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## Holt

Pictures must be on reassembling ;D The reason i had to remove the leadscrew was because the halfnut (yes there are only one) are broken it's item No. 2 on the drawing






This 3/4" pin is broken 






It looks to be cast iron, is it okay to heat shrink (is it called that?) a new piece into that?
I was thinking of milling a 14mm hole in the remaining piece, turn a new pin 0,05mm larger than the hole, heat the halfnut on the cooktop and put the pin in the freezer before assembling.
I have done this many times before with great success, but never with cast iron. I could be afraid it would be too brittle and crack.
If anyone has experience with this, please let me know


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## steamer

I think I'd stay away from shrink fits inside that CI nut....I'd be worried about splitting it.

I would use "Loctite" 680.  If you can get a new shaft nearly 1/2 to 3/4 deep in the nut, it will NEVER come out....and it will be low stress.


But first, get the rest of it out and post a picture.


Dave


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## Holt

This is what it looks like






It sits in the apron like this (the apron is pivoted around the feed shaft)






Holt


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## Mike N

I would drill & tap a hole & screw in a hardened shoulder pin w/loctite.


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## Holt

I have been thinking of that, but i think i will make a light fit, glue it w. loctite, and secure it with a bolt from the underside, like this






Holt


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## coopertje

Hi Holt,

Nice work on the lathe so far and some good puzzle solving. 

Why not mill off the broken part of the shaft, drill a hole and make a complete new shaft with a smaller diameter at the end (half nut side) and lock tide that in the half nut? To be sure you could pin it or fix it with a grub screw. 

Good luck and keep the pics coming!

Regards Jeroen


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## techonehundred

I know that pictures kind of skew depth perception, but will there be enough room to put in the capscrew? It looks like there is a threaded hole that would be right in the way.


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## steamer

Holt, I like your idea, but don't make it a press fit.  To make loctite work, you need some clearance between the shaft and the hole.  .002 inches (0.05 mm) on diameter is fine.

If your worried about location, lightly knurl the new shaft for a slip fit.  That will leave enough room for the loctite.

I would also use the bolt that your sketched.  It will put the remaining part of the shaft in compression and it will be less likely to break there again.  I would use a Grade 8 bolt but torqued to Grade 5 specifications.  That way you get the strength of the High Tensile steel, but not strip out the CI from over-torqueing.

Make sure the part is VERY clean, I have had good luck with Lighter fluid (Naptha). I would recommend the primer that Loctite sells. 

You won't have much time to get the joint together...with primer maybe 1 minute or less....so be prepared to go!

I'll promise you this, if you follow directions, it won't come apart without a large hammer or a blow torch!.....maybe both!

Dave


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## Holt

I had to open the norton box because i couldn't engage the 3 gears to the right, and some of the other was difficult to use







once i opened it, i realiced that i wasn't the first to be there. Guess what was interfering with the gears






A centerpunch was partly blocking the "come" making it impossible to engage some gears.
I didn't know the lathe came with a hide and seek toolkit! ;D

Holt


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## n4zou

Lucky for you it was a punch and not torn up gears.


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## steamer

Buy now! and we'll throw in this fine precision punch kit for free!  But wait ! there's more! :big:


Glad it didn't tear up the gearbox instead of just being an annoyance

Dave


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## steamer

Hey Holt!....Hows the project coming?... 

Dave


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## Swede

That punch is a hoot. When I was re furbishing my 1950's vintage Hardinge lathe, I had detached the steel way plate from the base casting, to find the casting voids PACKED with fine swarf. Inside the chips I found 3 or 4 nice taps, a die, and several small lathe bits. It was odd that these old tools not only got mixed up with swarf, they also somehow made their way into the casting void areas.


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## Holt

The halfnut is repaired






There wasn't room for the M6 bolthead at the bottom, so i reversed it, and made the treads in the halfnut, perfect fit!






I only had Loctite 603, but i think it is an advantage because it don't require total cleanness, which can be difficult to obtain in old Ci, that have always been soaked in oil. I used Loctite accelerator


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## Holt

With the halfnut repaired a new obstruction occurred, the halfnut couldn't be mounted because of the feedshaft being in the way!  






So the next thing to do was remove the feedshaft, mount the halfnut, and assemble it all. sorry no pics of that.
Just a hint to other doing the same repair: The handle and cam disc for the halfnut must be removed, and first mounted when the halfnut are in place, the cam disc slides right under the halfnut

Holt


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## Holt

As promised a pic of how to remove the leadscrew from a roundhead Colchester, it looks to be the same principle on them all (at least triumph and student).
It isn't necessary to remove the front of the Norton box, but it makes access easier.Mark the nut in some way, so you can see which side is against the trust sleeve
Start by sliding the retaining ring to the left. Remove the grub screw,and turn the nut loose (right hand treads). Carefully slide the leadscrew to the right, securing the retaining ring, the shim besides it, the two gears and the nut.






Holt


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## Holt

Yesterday afternoon once again i drove my son to sax practice, and once again i had 1½ hour to kill, so off to work i went, and turned some more oilers.






And here they are, 14 more, making a total of 23 which should be enough for the whole lathe. now i just have to harvest the springs of all the ball pens in the family


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## coopertje

Nice repair Holt! Must give you satisfaction when things are coming together.

Like your oilers too.

Regards Jeroen


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## Holt

Well, there is always something isn't there  this time it was the front cover of the Norton gearbox.
Someone, probably many years ago, overtightened the bolts and cracked the area around the bottom of one of the countersunk holes. 






In this area, there isn't support all the way around the threaded hole, making it easy to crack the cover.






I whacked the broken part off with a bolt and a hammer, leaving me with a clean 14mm hole, just the right size for M16. I threaded the hole, and made a plug from some threaded rod, drilled 10.3mm as original. i glued the plug into the hole with Loctite 549







The bolthead will be sitting higher than the other, but it won't be in the way.











Holt


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## steamer

Nice fix Holt!  :bow:

You end up having to get creative with these old lathes .....

Dave


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## f350ca

Coming along nice Holt. Mine only got enough TLC to get it working. Would sure appreciate a sketch of those oilers, they turned out nice and mine needs them.
Thanks
Greg


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## n4zou

f350ca  said:
			
		

> Coming along nice Holt. Mine only got enough TLC to get it working. Would sure appreciate a sketch of those oilers, they turned out nice and mine needs them.
> Thanks
> Greg



McMaster-Carr has them. http://www.mcmaster.com/#standard-oil-cups/=gx8lo0


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## Holt

Thanks for the comments.
I made chips today!!! The hand crank (is it called that?) on the cross slide was broken when i got the lathe. Only a piece of treated brass was left in the handle for me to drill out. Well naturally the treads was imperial, and here imperial bolts are as rare as unicorns, so i decided my first project was a new hand crank. I started with cutting 3/8" treads on the end of a 10mm Allen head bolt and 7/16" treads on a 12mm bolt (i want to upgrade the main handle as well) I got a piece of stock delivered with the lathe, it turned up to be stainless, and in the right size for the handle.






The handle might be a little too long, but it feels just right to use, and it rotates on the bolt, which the original didn't, and that's the reason for upgrading the main






Holt


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## Holt

I just finished the hand crank for the main slide, i have shortened the one on the cross slide to make it a little more appropriate






The next thing will be the tailstock handle, the one i am using now just don't look right although it works allright ;D






I got one with the lathe, i don't think it's the original, but it will do the job, just need a bush,and perhaps a hand crank


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## Holt

Can anyone tell me the meaning with this scale on the cross slide, every ten divisions (from 0 to 10 etc) moves the cross slide 0.25 mm, reducing the diameter with 0,5 mm






It's the same on the compound, maybe i just have to mount the DRO in a hurry

Holt


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## steamer

Hey Holt,

Sounds like it's an imperial machine maybe?...... 0.010 inches x 25.4 mm/inch = .254mm...?

Dave


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## Holt

Hello Dave

I vas thinking that at first, but then i mounted my dial indicator, one full turn = 5.00 mm

Holt


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## Holt

The handle on the tailstock is mounted. I turned a bush from some of the stainless i got with the lathe, then i turned the hole in the handle to fit the bush.







I don't have a boring bar yet, so i use a long 8mm carbide mill i got from work. the normal carbide mills are send to regrind, but this one was a ball nose mill, they don't regrind those. I just grounded the ball nose away, and grounded a cutting edge at the end of one of the flutes, it works really well.






Bush mounted






Handle mounted on the spindle






I just happened to have an old 1/4 UNC tap, the same size as the treated hole in the handle, so i drilled a hole in the bush, and cut treats in it.

Holt


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## steamer

Imperial machine converted to a metric screw but with the old dials?........ ???


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## Dan Rowe

The dial shown in the photo has 200 divisions so a 2mm or a 4mm pitch lead screw would make the dial make more sense if it is to be a metric machine.

Dan


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## rhankey

Holt  said:
			
		

> Can anyone tell me the meaning with this scale on the cross slide, every ten divisions (from 0 to 10 etc) moves the cross slide 0.25 mm, reducing the diameter with 0,5 mm
> 
> 
> 
> 
> 
> 
> It's the same on the compound, maybe i just have to mount the DRO in a hurry
> 
> Holt



Sure looks like an imperial dial on what sounds like a metric screw.

Robin


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## Holt

Dan Rowe  said:
			
		

> The dial shown in the photo has 200 divisions so a 2mm or a 4mm pitch lead screw would make the dial make more sense if it is to be a metric machine.
> Dan



In order to make sense, it should actually be a 10mm pitch (or 1mm, but require a lot of turning) to fit the dial

Holt


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## Dan Rowe

If you are using a trapezoidal metric thread then 1mm pitch is not standard and 10mm pitch is a big diameter. My suggestion of 2mm or 4mm pitches are ISO standard sizes.
http://www.roymech.co.uk/Useful_Tables/Screws/Trapezoidal.html

2mm travel for 200 divisions seams fairly simple to me.

Dan


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## Holt

I was thinking about what was easy to use, if the scale dosn't add up to the dia. of the workpiece, i could as well keep the existing wrong system instead of changing it for another wrong system

Holt


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## n4zou

Put a dial indicator magnetic base on the carriage with the indicator set to read the distance of the cross slide moves as you turn the cross slide handle. You will quickly discover what the dial is marked for. When I'm doing precision work I always set up a dial indicator this way so it performs the same way a DRO would at a fraction of the cost. I was working as a machinist before anyone even thought up the concept of a DRO. 


			
				Holt  said:
			
		

> Can anyone tell me the meaning with this scale on the cross slide, every ten divisions (from 0 to 10 etc) moves the cross slide 0.25 mm, reducing the diameter with 0,5 mm
> 
> 
> 
> 
> 
> 
> It's the same on the compound, maybe i just have to mount the DRO in a hurry
> 
> Holt


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## Holt

n4zou  said:
			
		

> I was working as a machinist before anyone even thought up the concept of a DRO.


I also know how it is to work without DRO. In my time as apprentice, 30+ years ago we didn't have DRO, neither the chemical plant nor the school had DRO on their machines, the two next places i worked at, had no DRO, then i got work at a small local toy company (LEGO ;D) *they* had DRO on all of their machines. Then i worked six years at a small company repairing their injection mould machines, we had a small stangko lathe and an old mill/drill without DRO, so i have done my share of reading scales 

Holt

PS: what should i do with my jaws, they are pretty worn, and have apparently been milled/grinded quite a few times. I was thinking of arc welding them with some hard material, and regrind them. I could also grind the slant part of them, to bring them closer, but the inner step get quite small this way. Any suggestions ?


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## Swede

If you are comfortable arc welding, then building them up with an appropriate alloy would definitely work, but obviously you need not only the welder, you'll need the ability to do some precision grinding.

Re: your cross slide screw and dial... Don't mean to sound like an annoying grade-school teacher, but are you SURE the slide is moving metric? The obvious way to really check would be to expose the screw threads and check their pitch with a ruler or compare with a thread gauge. You have the tails stock screw exposed, is it metric or imperial? I'd be amazed if just one screw is metric and the others are imperial. If they refitted the machine to metric leadscrews, they'd have done them all, I'd think.

Nice work!


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## n4zou

Swede  said:
			
		

> If they refitted the machine to metric leadscrews, they'd have done them all, I'd think.



Unless someone stuck something in it to get the lathe going again with no care about the problems it would cause. I remember the owner of a machine shop I worked for went to an auction and purchased a lathe. When it got to the shop and put in operation it was found the cross slide ACME lead screw has been replaced with cheap all-thread you would find in a hardware store. They had run a tap through the ACME lead screw nut to match the all-thread so it would function when you turned the handle. The repair did not cost very much to get it right, it was the down time to make the repair that cost him. He had already contracted work for that lathe before we found that bastard repair.


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## Holt

Swede  said:
			
		

> Re: your cross slide screw and dial... Don't mean to sound like an annoying grade-school teacher, but are you SURE the slide is moving metric?


I have had my dial indicator mounted at the cross slide, it measures a bit over 10 mm total, at two full turns (exactly) the dial indicator moves 10,00mm (exactly) The compound moves twice the distance as the scale (double up on that also) The main handle doesn't have a scale, but i believe it moves a odd distance at each turn

Holt


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## Holt

Swede  said:
			
		

> If you are comfortable arc welding, then building them up with an appropriate alloy would definitely work, but obviously you need not only the welder, you'll need the ability to do some precision grinding.



In my youth, i took a certificate in arc welding, but haven't used it in many years, with some practice i should be able to refresh it (almost as riding a bike ;D) When working as a toolmaker, precision grinding is everyday work, i have access to this:






And this:






And this:






Said in other words: Grinding wont be a problem ;D The real precision grinding isn't done until the jaws are back in the lathe anyway, i have a small grinding spindle from the tacchella universal grinder, i could use for that.

Holt


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## Swede

Building up and regrinding the jaws... you've got the skills and the tools, GO for it!  ;D Then post some pictures!


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## Holt

As i have written before, i wanted to weld and grind the jaws, because they were very worn. I was talking to my boss today, and it turned out that we had some tread for the tig-welder, that hardens when welding, and this afternoon, i took the jaws to work,and started the job. Unfortunately i forgot the camera, so you have to settle with some before, and after pics.






I started by milling some 6mm holes in the jaws, with a carbide mill






Then i welded and grinded them. I used the Okamoto grinder and sinus plane, shown in a previous post, to grind the tapered area. It turned up that there was some small holes in the welding, but i have to live with that 






The holes are made for two reasons, now i can use them, to clamp a piece of pipe when grinding the jaws in the lathe, and later they can be used when clamping thin shims












Holt


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## Holt

I didn't get a grinder home for the weekend, so i had to bore the jaws, i used a long solid carbide mill, and it went very well, already at the second light cut, i noticed the cutter touched all 3 jaws  I took some more cuts to widen the contact area, but the rest have to wait until i get a grinder






Holt


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