Member postings for mark smith 20

I moved my Alexander mill on the hottest day of the year where i live, wasnt much fun. I also had it in the garden for a couple of week under tarpaulin when first delivered which was an ordeal in itself getting into the back garden down several steps and a narrow path with various obstacles in the way such as a side gate with 0.5cm room to manouvre it through .

It arrived with a guy i know who delivers racing bikes every week or two up here to be reviewed and test drived in the lake district.

We had to remove this huge fancy Ducati first before we could even get at my mill in the back of his small Luton van with tail lift.

All the bolts were seized so i could only remove the vertical head and swiveling table to reduce the weight a bit down to about 600-700 kg .Took us 2 hours just to get it out of the van onto the pavement ,with straining tail lift which slope forward and a winch attached to prevent it tippling.

Finally managed to get a pallet truck under it , down a step using two ramps he uses for the bikes and half way down the path with a slight slope .

The pallet truck started speeding up and it ran into the gate post breaking off the sticking out bit on the x axis hand wheel .Also trapped a lump of skin on my upper arm which was agony until we managed to back up the pallet truck a bit.

Eventually got it over an open drain, over another step and round the back garden . I said the delivery bloke could leave it there.

It sat there for 2 weeks whilst i decided how to move it into the workshop which has a low single door entrance and a 1 foot drop down to the workshop floor. I decided to concrete the floor to raise it up to just above outside garden level.

Then i bought a Gorilla bar , cut up an old bed frame made of angle and used the angle point up as rails . I was surprised how fast i got it into my workshop with just myself ,a gorilla bar and some candle wax on the angle iron rails.

I wouldn`t have had room for an engine hoist etc..

Looking at the weight of a VMC mill ,the original poster mentions ,at 500 kg it should be relatively easily managable with some parts removed and perhaps an helper.

Michael , my chemistry is a bit rusty ,having looked around google it appears it has been used often for gluing plastics. So i wont go into it other than id expect dichloromethane to be a more effective solvent for acrylic but with shorter working time and chloroform possibly causing more stress fractures. Which is probably why dichloromethane is more used in commercial products. (though appears to have been removed from consumer based paint stripper like nitromors (which is now crap)

They are both similar solvents only different is the chloroform(trichloromethane) has 3 chlorines attached instead of two. . I have used chloroform for dissolving amber.

Also id like to debunk this myth of tv films ,dramas where someone puts some chloroform on a rag and knocks someone out instantly . Virtually impossible in real life unless the person is a willing guineapig and sits there for quite a while, without struggling.

Edited By mark smith 20 on 11/12/2016 12:24:39

tensol 12 is one of the things i used which failed, funny though as it exactly the same as dissolving powdered acrylic in dichloromethane. I had never heard of using clhoroform and being a chemist i wouldnt have thought it would be as effective as dichloromethane (methylene chloride).

Ive used dichloromethane for bonding acrylic , never used chloroform for it(does it even work?).

I have a metre long 5" diameter perspex tube that i used in my work for fuming wood using conc. ammonia. I had to bond a cap on one end and used the dichloromethane with acrylic filings. It has held for 2 years now ,although i did have to overlap the joint so that it appears like a weld.

Previous attempts ( using superglue and other specalist acrylic glues) held for between 1 week and a month and it wasnt much fun having the bottom falling out and the ammonia going everywhere..

Edited By mark smith 20 on 11/12/2016 10:50:00

John , it doesnt matter ,i `ll try cutting the gears once i get the broken bush sorted out.

Bazyle, i dont understand the split worm wheel either ,id never heard of one until someone mentioned it, i also dont want to fiddle with it either ,in case i alter the adjustment.

The manual describes 3 screws ,even though they are 5 in the worm wheel. One described as just a screw, another a worm screw and one an eccentric screw.

I think its supposed to do something like this.

Edited By mark smith 20 on 10/12/2016 00:30:07

Edited By mark smith 20 on 10/12/2016 00:32:36

Nick , tried that first it didnt work

Anyway finally made progress ,i decided only way was to remove the spindle by slackening the locking nut and tap with a hammer on wood on the back end of the spindle. Because the worm wheel is keyed to the spindle the slackening of the locking nut and tapping released the spindle without damaging the worm shaft or wheel. Once out i just put my hand in and lifted the worm wheel out.

Then i tapped on the front end of the worm shaft which drove the broken bush out. The thrust washers on the worm shaft next to the broken bush were all rusted up and one is still rusted on and wont move.

I still cant see the split in the worm wheel ,which must be there as its indicated in the parts diagram and the adjusting screws on the worm wheel itself.

Hi Thanks for the further ideas, i am terrified of breaking any other part ,hence the caution. The other side of the worm shaft also has a flanged bush ,see photo. Although i have the parts diagram i can hardly see anything of the worm shaft on the inside and certainly dont want to strip any teeth on the worm wheel.

The worm wheel is a split type which id never heard of and cant even see the split down the middle . I assume its for some sort of backlash adjustment . Other bigger heads have an essentric shaft to disengage the worm this doesnt. Heres a few photos of the inside as well.

I didnt know what a slide hammer was but looks useful if the worm shaft was clear of the worm gear wheel.

Edited By mark smith 20 on 08/12/2016 10:44:46

I`m not sure that would work as it is, as the worm cant be just easily disengaged from the worm wheel. It has, ive been told a split worm wheel instead which would have to be removed along with the spindle ,before i could pull on the worm shaft.Though not certain if im understanding correctly.

Im not sure theres enough room for to  drill a hole and tap unless it was very small diameter?

Edited By mark smith 20 on 08/12/2016 00:03:44

Anyone any ideas how to get this out ,its the remains of the broken bushing ,it extends about and inch or more into the main body with the worm shaft going through it . It is whats left after the end of it shattered .

I tried filing a couple of flats on eith side but there is hardly any material on one side of it(so hard to avoid damage to the worm shaft.). I managed to turn it on th eflats with a spanner but no change of getting a good grip and wiggling it out.

Thanks

Edited By mark smith 20 on 07/12/2016 20:48:35

John S, ive took some measurements ,sorry about the crappy freehand paint drawings.The measurement may be slightly off due to wear .

The first is gear in the middle

the second is the one on the same shaft as the worm which the dividing plate attaches.

the last is the one attached  by two grub screws in the end to a  shaft with the undamaged helical gear on.

Edited By mark smith 20 on 07/12/2016 12:35:42

Edited By mark smith 20 on 07/12/2016 12:37:18

Edited By mark smith 20 on 07/12/2016 12:40:43

Edited By mark smith 20 on 07/12/2016 12:43:41

Phil, yes i would be interested in any drawings you have,are they in digital format?

Thanks

Andrew , sent you a PM.

Hi John, I`ll measure them tomorrow ,Thanks

Hi Just bought this on ebay after wanting something of suitable size ad deciding whetehr or not to make one .

Anyway it was advertised with 2 broken gears ,although has a nice burnard 6" four jaw which from inspection looks like it will clean up like new with no jaw wear.

On taking it apart (or trying to) i discovered another broken gear under the cover! I knew it may have other problems when i bought it so not too annoyed about that . But on trying to be clever and dismantle it without any manual or instructions i buggered up the part on the end of the worm(on the opposite side of the main body).

I dont know what i was thinking at the time but thought it was just a cover so gave it a little tap with a very thin metal knife edge after removing the 2 socket screws and a hammer and the whole bit shattered leaving what looks like half of it in the side of the dividing head. I wasnt expecting the boss on the other side of the diamond shaped bit.

Anyone have an info on these heads ,such as how to get that broken bit out .

Also the gear info . all the broken spur gears appear to be 26 teeth and possibly 16DP.

Anyone have a parts diagram they could post??

Rather annoyed with myself.

Edited By mark smith 20 on 06/12/2016 20:47:04

Edited By mark smith 20 on 06/12/2016 20:48:44

Edited By mark smith 20 on 06/12/2016 20:51:48

chester sell them at £50 quite expensive though i`m confused why they state they are for the 920 lathe but are listed at M40x 4mm????

Looking at the fortis gears photos on lathes.co.uk website it doesnt have a banjo so im not sure how you could do this on yours ,others maybe know more.

Sean, i was wanting to cut some metric threads on my southbend . The 127/100 compound gear costs anything up to over £100 for boxford /southbends .

A kind American sent me a metric calculator spreadsheet which shows what effect changing the various change gears has. Also shows the pitch errors. I found i could cut 0.5mm, 1.0mm, 2.0mm and a few others ,just by changing my 56t drive gear(one attached to the gearbox ) with a 79T change gear. Was only £20 compared to the costly 127/100 gear.

Im a novice myself to screw cutting and found it relatively easy to follow.

I dont know how or if there is a similar spreadsheet that can be used for the fortis but other may know, and maybe this one will work.

Hope this helps

Edited By mark smith 20 on 03/12/2016 11:34:46

Your lathe will have a 3mt probably and the bore is probably small ,my 9a has 3 c collets and i think they only go up to about 1/2".

I would find a 3mt ER collet chuck of some sort and make some sort of drawbar out of threaded rod .

http://www.arceurotrade.co.uk/Catalogue/Collets/ER-Milling-Collet-Chucks-Morse-Taper-Shank/ER40-Milling-Collet-Chucks

or try one of these but you`ll need a threaded backing plate to fix it to.

http://www.arceurotrade.co.uk/Catalogue/Collets/ER-Lathe-Collet-Chucks/ER32-Lathe-Collet-Chucks

Edited By mark smith 20 on 28/11/2016 19:32:47

Whats the size of the pulley? Is it a b section?