milling spindle upgrade

[bertie_bassett]

drove home from work today thinking the van felt a little sluggish, opened the back up when I got parked and found this!!

[Sid_Vicious]

That looks like a nice find, where are you parking when you find this kind of stuff in the car on the way home?

[RobWilson]

 I do believe  a Chester 626 mill    what happened to the foot casting ? 


Rob 

[vtsteam]

Must be Robin Hood of the Mills did that. Try to find the owner -- there may be a few bob for you Bertie, in a reward!

[bertie_bassett]

oh im trying very hard to find its owner ;) 

must catch that robin hood chap, seem to have dipped into my wallet whilst on his rounds!!


rob :- it is indeed a chester 626, unfortunately I believe it tried to roll off of the forklift and broke its foot casting and bent its knee screw.

[vtsteam]

oh im trying very hard to find its owner ;) 

must catch that robin hood chap, seem to have dipped into my wallet whilst on his rounds!!


rob :- it is indeed a chester 626, unfortunately I believe it tried to roll off of the forklift and broke its foot casting and bent its knee screw.

Typical Robin of the Mills -- not good with a forklift. I hope that happened prior to your wallet shrink, and not after?! Hope you didn't have a Mawson Moment! 

[bertie_bassett]

damage was done a while back I think. been laying in a barn for a little bit I think.

was surprised how easy it was to dismantle. and fit in the van

tomorrows job will be getting it out on my own and down the garden into the workshop!

[RobWilson]

rob :- it is indeed a chester 626, unfortunately I believe it tried to roll off of the forklift and broke its foot casting and bent its knee screw.

That will do it every time Burtie    , what your plan for fixing the bent Z axis  screw ?    , I think I still have a one lying about some were  yours if you want it 


Rob

[bertie_bassett]

plan to fix the bent screw??  bend it back ;)

thanks for the offer rob, I may well take you up on that. though I am also thinking of adding a riser block, so may need a longer one.

as for the casting, im just going to use a bit of flat plate instead, iv got some 9mm thick stuff which might do the job. and could buy some box sction to add strength and raise it back up if needed

[bertie_bassett]

Well after a couple of hours on my own in the rain iv managed to get it all into the workshop and onto the bench.

Now to start cleaning, then work out what to do about the base

[John Stevenson]

Bertie,
Resize your pictures please you are taking up 4 1/2 post codes.

[mcostello]

No pictures showing, Did You close the van door?

[bertie_bassett]

sorry took them off to resize them, and now cant get them back up !

[bertie_bassett]

hopefully these pics will be a better size, think I've done it right


managed to spend a few hours cleaning today, used up most of a can of ipa! 

also managed to straighten up the screw by holding it in my vice and having a short tube on the other end. didn't take much effort. though worryingly the workshop wall seemed to be moving :S

[vtsteam]

I think you got rid of the barrel distortion when you photoshopped that second pic of the leadscrew -- excellent!

[bertie_bassett]

I think you got rid of the barrel distortion when you photoshopped that second pic of the leadscrew -- excellent!

amazing what can be done with a computer isn't it!

[bertie_bassett]

now that its mostly clean iv started loking at reassembly

not quite sure what to do about the broken base though, its too damaged to be repaired and original plan was to just use a 1/2'' flat plate instead,

problem is the only plate iv got is about 9mm thick which should do the job, but.. I did find this at work earlier..





moves things up to the right height, it would be the right length ( once the end was cut off) but doesn't really fit width wise, plus the mill column  is only resting on 2 edges. I possibly could find some more metal to weld to it but not sure its worth the effort

so what ideas do you guys have?

flat plate puts the top of the column at 4ft high, im concerned it may be too low ( though im not that tall so maby not?)

[Will_D]

now that its mostly clean iv started loking at reassembly

BB: Is that a RO (Reverse Osmosis) setup in the backgroung?

[bertie_bassett]

It is one of my RO units yes, not actually ever used that one since I was given it. Nit got round to getting filters for it

[RobWilson]

Nice job getting the spindle straight 

Thats a canny crack in the base 



Rob

[bertie_bassett]

Thats a canny crack in the base 

Rob

think its repairable??  iv got some jb weld


been thinking things over and have decided to go with the flat plate for now, as its simpler and I reckon it will be strong enough. the loss of height isn't really an issue ( I think) and will certainly make changing belts easier!

plus if I do eventually go with a 4'' riser block, the head will end up back at its original height

[philf]

think its repairable??  I've got some jb weld.

Funny you should say that! Have you got all the bits and are they big pieces?

The base on my Aciera mill must have been dropped and badly broken before I acquired it. It's held together with something like JB Weld and steel brackets and plates on the inside - you wouldn't know from the outside. I must have had it for for nearly 30 years and it's still going strong.

Phil.

[Swarfing]

If yo got all the pieces for the base, stick it back together and use it as either a plug to cast a new one out of ali with thicker walls? or use it to cast a  a thick walled plug you can then bond inside the iron base with some epoxy resin. Keeps it original looking and very strong?

[vtsteam]

Along the lines of what these guys are suggesting, stick it together with JB Weld, screw some straps under across the cracks with countersunk screws from the top, leave them long, then invert and fill with concrete. The screws will help bond the concrete in, though it would probably be sufficient without. It'll be heavy but, that's a plus other than for moving it. A cross of 1/2" rebar, corner to corner set in the concrete wouldn't hurt either. Fill any bad spots from above, sand and paint.

[bertie_bassett]

Hmm I hadn't thought about filling it with concrete.  Not a bad idea.

Its in three big sections, though I'm missing a bit.. Will pop back to where I got it and see if its still there.

I did also consider sticking it together ontop of the plate and then building a support under the main column

More things to think about.

[Swarfing]

If you do go that route then i would recommend a resin mix and not cement. No chance of it rusting out from the inside going forward, a cement mix would allow damp/ water in.

[vtsteam]

I haven't had that particular problem swarfing when filling metal buckets for stands, etc. Also I have a cistern coated inside with portland cement under the house. Portland cement neat is waterproof. Many ferrocement boats built with it, and swimming pools,etc, Pipes run through slabs, not to mention rebar, ----- and how often will this base sit in water anyway?

Just use a rich mix (extra cement). if worried. You could paint the bottom, too, I can't imagine a problem here.

[mattinker]

The problem with cement is more shrinkage than rust, if the block shrinks its vibration damping would be reduce. Resin based concrete would seem to be a better solution.


Regards Matthew

[bertie_bassett]

well while I decide what to do with the old base I decided to drill some hole in the plat iv got and make a start at re-assembly -  got the plate bolted down, but both drills ran out of juice so couldn't mount the actual column today

i did manage to repair the damaged nut though

started with this



first i set the base up in the chuck, and clocked off the internal bore



faced off the damaged section till it was nice and flat then did the same to the nut section

i then found a handy lump of ally from my 'might be handy' bin, think it was an old shaft adaptor for an actuator or something

chucked up on a quickly made mandrel and skimmed the outside down to match the bore, added a few small grooves to aid glueing together



left the internal bore as found, thinking the thicker the better



is now clamped up waiting for the jb weld to dry.  i might drill and tap a few spots for extra strength but will decide on that later


as for the broken base here it is in situ



current thinking is to jb weld it together, along with some internal plates and then build some sort of box/stilts directly under the column to take the majority of the weight and brace directly to the plate underneath.
would weigh less then concrete and should be easier to construct.

[awemawson]

That looks a likely candidate for metal stitching:

http://www.locknstitch.com/metal_stitching.htm

[vtsteam]

The problem with cement is more shrinkage than rust, if the block shrinks its vibration damping would be reduce. Resin based concrete would seem to be a better solution.

Nah, it isn't going to shrink. But if fashion and too much extra cash dictate, fill it with epoxy.....

[Manxmodder]

Steve,really, concrete boat,who ever heard the likes. We all know it would sink like a stone 
.....OZ.

[vtsteam]

Steel is even denser, and we all know steel boats can't float! 

(A 1" hole will make it all to too true,  though, OZ!)

btw. "hydraulic" cement expands on curing. Used to fill cracks, etc. And bolting the base to a solid floor makes the fill irrelevant re. vibration.  Though flilling it with anythling is a lot better than it was as a hollow casting.

[mattinker]

The problem with cement is more shrinkage than rust, if the block shrinks its vibration damping would be reduce. Resin based concrete would seem to be a better solution.

Nah, it isn't going to shrink. But if fashion and too much extra cash dictate, fill it with epoxy.....

Nah,
http://www.cement.org/for-concrete-books-learning/concrete-technology/focus-on-floors/concrete-shrinkage

[vtsteam]

This is a little smaller than a floor. 

I've got cast in place steel containers for stands. They're solid.

Concrete filled steel lolly columns can be bought at local lumberyards. The cores don't fall out, even when cut. We've used sections of them for rollers for boats weighing tons. They don't even have fasteners through the sides as suggested earlier for the mill base repair. Or rebar, etc. Classic case of internet research and theorizing vs reality.

[PekkaNF]

This is a little smaller than a floor. 

I've got cast in place steel containers for stands. They're solid.

Concrete filled steel lolly columns can be bought at local lumberyards. The cores don't fall out, even when cut. We've used sections of them for rollers for boats weighing tons. They don't even have fasteners through the sides as suggested earlier for the mill base repair. Or rebar, etc. Classic case of internet research and theorizing vs reality.

Or maybe manufacturer is smart and adds something on the concrete mix? I have met concrete that has something added to to it to EXPAND it intially to outmanouver further shrinking.

Something like this:
http://www.puumarket.ee/?op=body&id=42&prod=269&sid=2104
That english translation looks funny, but I'm not familiar with the real one.

Anyways, I have tempted to measure real world concrete shrinkage on our machinebuilding application, but been putting it of for years, because can't get any immediate results

Pekka

[bertie_bassett]

Well the concrete casting is still on the maby list, though I don't really fancy the weight of it  a concrete slab with 1/2" cast iron skin sounds rather heavy, and ill have to move it on my own. Also the column is tapped and bolts down from underneath so not sure how id get around that one

There is such a thing as expanding concrete. Usually used to fill in holes in the ground. Just don't use it indoors as it gives off hydrogen. Had a one of my pumping stations explode a few years back, when contractors used the stuff

[NormanV]

On page 75 of the book Stuff Matters by Mark Miodownik he states "But, as luck would have it, steel and concrete have almost identical coefficients of expansion"

[vtsteam]

Apologies to Matt for tone earlier.  It does bring up a topic I have often had to deal with. But no need for criticism.

I do think that theory online, in general often overwhelms what actually happens when tried in real life, and it's one of the reasons I do so much experimenting in my projects, despite what is published. I think there are online justifications for both sides of practically every techncal argument, and they're all true, to some degree.

One of the main reasons that is possible is that the devil is in the details, and online theories often generalize (or get generalized by repetition or expansion) to the point that they are meaningless to many specific cases. Generalizations are common. Specifics, and expressed theoretical limitations, rare. And that stifles experimetation and discovery. Specifics, accident, and even failure are essential to the realization of many projects, and innovation. And much learning about the world.

I ought to be from Missouri, though Vermont is considered a fairly independent minded state, too. I like to do things and find out what happens for myself, or if I can overcome conventionally perceived limitations. Anyway, sorry about the exasperation level expressed, but it's not personally directed -- it's the internet "knowlege base". Taken as an approximation of reality it's helpful, otherwise, I find it frustrating at times. 

[mattinker]

Apologies to Matt for tone earlier.  It does bring up a topic I have often had to deal with. But no need for criticism.

I do think that theory online, in general often overwhelms what actually happens when tried in real life, and it's one of the reasons I do so much experimenting in my projects, despite what is published. I think there are online justifications for both sides of practically every techncal argument, and they're all true, to some degree.

One of the main reasons that is possible is that the devil is in the details, and online theories often generalize (or get generalized by repetition or expansion) to the point that they are meaningless to many specific cases. Generalizations are common. Specifics, and expressed theoretical limitations, rare. And that stifles experimetation and discovery. Specifics, accident, and even failure are essential to the realization of many projects, and innovation. And much learning about the world.

I ought to be from Missouri, though Vermont is considered a fairly independent minded state, too. I like to do things and find out what happens for myself, or if I can overcome conventionally perceived limitations. Anyway, sorry about the exasperation level expressed, but it's not personally directed -- it's the internet "knowlege base". Taken as an approximation of reality it's helpful, otherwise, I find it frustrating at times. 

Apology accepted! I am well aware of how you function, we've both been contributors to this group for some time now. My feeling is that I have a certain amount of knowledge that I can share. Take it or leave it, but know that intentions are good!

Regards, Matthew

[vtsteam]

Well the concrete casting is still on the maby list, though I don't really fancy the weight of it  a concrete slab with 1/2" cast iron skin sounds rather heavy, and ill have to move it on my own. Also the column is tapped and bolts down from underneath so not sure how id get around that one.

Bertie, if it's too heavy, that's that. But if not, you can screw waxed dowels over the holes on the inside as cores to prevent the fill from coverng the tapped hole. You can knock those out after cure. Taper them to make it easier.

[Swarfing]

Guys the only reason my thumb up for a resin solution is that you get a natural adhesion to boot so no need for extra bracing and fixings. I worked in the flooring industry many years ago dealing with all types of concretes, resins and aggregates. Like all mixes it all depends on how much air is excluded to decide how porous the material is. The filler material will really be the deciding factor plus any reinforcing if required like a square of welded mesh, cost wise (UK) two pack resin vs cement would be very little in it.

The piece that is missing you could just box in so the resin mix fills that. A bit of bondo afterwards and a sand/ paint and your done.

[bertie_bassett]

well iv got it bolted down on the flat plate and started re-assembly.

actually quite like it at the lower height, only issue so far is that the knee handle hits the lower tray when the knee is at the lower 2 inches or so, can live with that for now as I doubt ill need it that low down often.

the straightened screw seems to be working well, is a little tight in the middle but not excessive.  and will do for now

[bertie_bassett]

and its alive!!


spent some more time today putting the table on then reassembling the head.





wired up a temp lead direct to the motor as I didn't like the standard wiring, luckily it spun the right way first time! 





that's about all I can do for now, don't have any tooling or a proper vice.

[philf]

Looking good!

How thick is the base plate?

If it's at all flexible you may have problems in that the table might move relative to the cutter when actually cutting metal! If you're not going to reinstate the original base a piece of 20 or 25mm plate (or a piece of substantial channel section) under the column and extending to the nut would help.

Cheers.

Phil.

[bertie_bassett]

plate is about 9mm thick and bolted down to all 4 corners of the angle frame of the cabinet, ill have to see how it goes when I get some tooling, can always be braced from below if required. or the base repaired.  though I quite like the height its at now belts are about on my eye line

[vtsteam]

Well that was quick! It does look nice! 

[bertie_bassett]

Well that was quick! It does look nice! 

Wasn't all that much to fix really, just the screw and nut.

Managed to find a small precision vice I made as an apprentice and a t slot slot clamp which fits perfectly so thats a start on tooling   will probably build my own vice for it along with everything else I need.
Collets and cutters are first on the list though!

Best I start on the other jobs, and many finish off the lathe milling spindle

[bertie_bassett]

not made any real progress since last week, was going to do some today, but after working 23 hours solid I decided to go to bed!

have orderd up a collet set  from arc got 6 10 12 and 16mm.  as thought that would be a reasonable start. also order up a range of 4 flute hss mill from richon to play with, so now just waiting on bits to arrive.

I did start making some adjustments and measuring of backlash, looks like I might need new gib strips as they go in further then I think they should also need to look at the slipt nuts on the x+y as they have been drilled but not tapped?? so plenty to keep me occupied.

oh and got to build a starter panel for it. original had reverse, but I cant see any reall reason to have reverse on a mill?

[PekkaNF]

..... original had reverse, but I cant see any reall reason to have reverse on a mill?

I can imagine reverse used on threading, but don't the new ones have button on the down feed lever?

Pekka

[lordedmond]

Reverse is useful for left hand drills to get out stuck studs, and as been mentioned running out taps

It's useful but not essential


Stuart

[bertie_bassett]

well my collets arrived from arc, seems to be a small issue though.. . they don't fit!


not quite sure whats happening but they go in about 50mm or so then stop dead. looks like there is a small 'pin' inside the spindle that should fit in the slot on the collets? seems either the pin is damaged and too big, or the slot is too small.

so. . what size should the slot in the collet be?

[lordedmond]

If it's r8 then this may help

http://www.cnccookbook.com/img/MillStuff/R8Dimensions.jpg


Stuart

[bertie_bassett]

thanks, yes its r8.  width seems right and I think depth is ok, getting 1.7mm at the edge so should be 2.4 (0.98) full depth. - no im  not going to calculate it.

seems I need to try and look up the spindle bore, see whats going on

[vtsteam]

A couple of mine get a little tight when putting them in -- they were like that new, too. Sometimes I have to wiggle them or bump them past the sticky point with my palm. Most of my collets don't do it, just a couple. But definitely no forcing, and nothing like a hammer. Just a couple palm bumps sometimes.

I hope your quill isn't bent from the fall.....

[bertie_bassett]

well the quill moves freely and the head didn't take any of the weight of the fall so I think im ok on that front.

managed to get a pic up the spindle bore and think the pins at fault, though the pic isn't as clear as id like





looks like the entire spindle need stripping down to be able to get it out though

[Swarfing]

I had to fettle the pin in my spindle slightly. I used a small needle file where one of the sides are blank, I just gave a couple of strokes up each side of the pin which was enough for it to work with all my R8 tooling. I found that the problem was only really on all the imported tools, UK tools were fine?

[bertie_bassett]

I was thinking of trying to clean it up, but need to be careful not to damage the taper.

Wouldn't suprise me if the imports were slightly different size to uk ones

[vtsteam]

Use a little blue (or other color) on one part and fit together. Pull apart to check and see where it's rubbing. Then you can take a little off only where needed.

[bertie_bassett]

Use a little blue (or other color) on one part and fit together. Pull apart to check and see where it's rubbing. Then you can take a little off only where needed.

do you have some sort of fetish for getting blue everywhere?  do smurfs need to be worried??

[vtsteam]

  No Bertie, I hate the stuff, believe it or not!

[tom osselton]

Remember that stuff the dentist use to give out to show people the spots they missed while brushing their teeth?

[bertie_bassett]

well I did a small bit of filing on the pin and got the 10mm collet to slide in nicely, the 12 is a little tighter but ok.  unfortunately the 16mm and 6mm are very tight, they will go in, but require more force then I like.

measuring the collet diameter im getting 24.11mm on the two good ones and 24.12mm on the two that don't fit well. have tried spinning them up in the lathe and polishing the collet with some light emery, but not made much difference.

looks like they are about 1 thou oversize.

my cutters also turned up yesterday, . at my parents. . so wont be getting my hands on those for a while