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View Full Version : The Boxford 260VMC as you probably never seen it before!



rnr107
21-04-2012, 06:58 PM
Hi All,
I bought a 260VMC a little while ago and converted it to Mach3. The problem was, The door of my workshop is only 65cm wide.
far too narrow to get the 260VMC thru it.... :(

I thought, no problem, I'll just take the mill out of its enclosure.... Nah! Boxford had the brilliant idea to cement the base and the back of the mill to the enclosure! Call Boxford, How do I get the mill out of the cabinet? ==>> Not possible sir!

Well, this was enough for me to give it a go.
1- move the table along the Y axis to both extreme position to expose the 5 M10 cap head screws. Take these off.
2- Place a scissor jack between the base of the mill (with a large piece of wood to protect and distribute the pressure) and the cabinet side.
3- start turning the screw a little bit at the time, slowly but surely! Crack!!! it's off! :-)

5810

Now we have a 260VMC on the bench... :-) run a few test, run nicely!

Time to start the cleanup before doing anything serious with it...
First, full disassemble!

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I'll add some pictures of the electronic if any interest... :)

Laurent

Ricardoco
21-04-2012, 11:52 PM
Well i have more than a little interest, so post away i look forward to reading..

i2i
22-04-2012, 12:38 AM
check the feel of the ballscrews, they are the weak link on that machine. Any notching or play they'll need to be replaced, i did one years ago and used ground 14x5mm pitch screws, also you'll need to sort out homing switches/sensors. Is your spindle R8, 30 int or coventry?

i2i
22-04-2012, 12:40 AM
Well i have more than a little interest, so post away i look forward to reading..Nice to see you back again.

rnr107
22-04-2012, 09:28 AM
check the feel of the ballscrews, they are the weak link on that machine. Any notching or play they'll need to be replaced, i did one years ago and used ground 14x5mm pitch screws, also you'll need to sort out homing switches/sensors. Is your spindle R8, 30 int or coventry?

Hi i2i,
The spindle looks very much like the EasyChange itself but without the grove for the balls.
It was a pain to take off! See picture bellow:

58165817


Where did you get your ballscrew from? did the new ballnut attach to the existing holders or did you make some new ones?
My X axis has no play at all, the Z got some play between the nut holder and the nut but not between the nut and the screw... How does the nut hold onto the holder? Is it screw in? I don't seems to be able to tight it...
The Y axis got some play.

Something else, I find the spindle a bit stiff. Is it supose to spin freely? I mean if I take the gear on the top of the spindle in my hand and give it a good twist, is it supose to spin a few turns? Cause right not, I can turn it easly, but it won't spin multiple turns if you see what I mean... The cap head screw on the top is it used to load the bearings?

5818

Laurent

i2i
22-04-2012, 10:00 AM
i used a company called BXR Ballscrews in Bideford, ask for Gerry.

i2i
22-04-2012, 10:12 AM
the ballnuts screw into the holders so they must be tight, and i would expect the cap head screw locates the easychange holder. Preload on the bearings would be from a clamp nut above the bearings, which by the sound if it may be too tight, it's hard to judge without seeing it.

rnr107
22-04-2012, 12:19 PM
Well i have more than a little interest, so post away i look forward to reading..
Hi Ricardoco,
I'll post the electronic for you... :-) I followed your 260 build and I see you like all these electronic gagets! :-)

I2I,
I had a quick look at that ballscrew page, But they seems to have the type of nut I am looking for only in the rolled type of screw...

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rnr107
22-04-2012, 01:38 PM
Well i have more than a little interest, so post away i look forward to reading..

Here is the electronic...
Old stuff first:

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Then the new stuff... I wanted to use rack mount 19" enclosure so it can be bolted underneath my bench, but could not find one big enough, so had to split spindle electronic in one box and steppers electronic in an other.

58215822582358245825

Got these nice rack mount enclosures from work. They've got extra holes on the front panel... I guess I will have to patch these at some point.

Laurent

i2i
22-04-2012, 02:32 PM
extra holes = lights.......lol


if you're parting with the original electronics i would be interested.

rnr107
23-04-2012, 07:58 AM
if you're parting with the original electronics i would be interested.

Hi i2i,
Can you collect from Bradford West Yorkshire ?

Ta,
RNR

i2i
08-05-2012, 10:41 AM
i may be going to the harrogate show sunday, could we sort it out then.

rnr107
08-05-2012, 01:21 PM
Could do... :encouragement: Would you come to my place?
Which bit do you want? I have the original stepper drivers, transformer + big caps, various relays , control panel...
I kept the spindle driver as it works fine with Mach3.
What do you think it is worth ?

Laurent

i2i
08-05-2012, 04:36 PM
Hi Laurent, the drives, rack, psu +caps and b/recs are all i need, the rest is boxfords own, so too old to be used. I can come to yours either before or after the show. No idea on value, these are more for for spares for old machines.

rnr107
08-05-2012, 05:49 PM
Hi Laurent, the drives, rack, psu +caps and b/recs are all i need, the rest is boxfords own, so too old to be used. I can come to yours either before or after the show. No idea on value, these are more for for spares for old machines.

OK.... What about 10 quids and a look at my mill ? :congratulatory:

Laurent

i2i
08-05-2012, 06:21 PM
sounds good to me.

rnr107
08-05-2012, 09:24 PM
Cool... Deal!

Ricardoco
14-06-2012, 11:17 PM
Hi Ricardoco,
I'll post the electronic for you... :-) I followed your 260 build and I see you like all these electronic gagets! :-)

I2I,
I had a quick look at that ballscrew page, But they seems to have the type of nut I am looking for only in the rolled type of screw...

5819
Hi there, did you manage to source some new screws for your 260 or did make do with the old, i only ask as my Z spat its balls out and im using a old lead screw as a temporary measure, but will replace all with new machined screws if i can find a reasonable priced source...

Rick

i2i
14-06-2012, 11:29 PM
you could machine out the ballnut mounting plate to take a standard flanged nut, and put up with the slight loss of axis movement.

Ricardoco
14-06-2012, 11:35 PM
you could machine out the ballnut mounting plate to take a standard flanged nut, and put up with the slight loss of axis movement.
Hi i2i, if i cannot get some of those threaded ball nuts thats what i will do its not like you would lose much using a conventional nut ...

i2i
14-06-2012, 11:49 PM
you'd loose the thickness of the flange. The guy i got the set off for my 260 can't get the same nuts anymore, and even those were remachined to fit the threaded mounts.

I've just helped someone put a 14 x 5mm ground screw on a 240 lathe x axis and it worked well.

rnr107
15-06-2012, 07:33 AM
Hi there, did you manage to source some new screws for your 260 or did make do with the old, i only ask as my Z spat its balls out and im using a old lead screw as a temporary measure, but will replace all with new machined screws if i can find a reasonable priced source...

Rick

Hi Ricardoco,
I found a company that makes 14mm ballscrew with a threaded nut but these were only rolled ballscrews not ground. But the original ballscrews on the VMC260 are rolled, so....
http://www.mooreinternational.co.uk/category-6/FGI14X4.html

I keep my existing ballscrew for now, I can not detect much backlash so far, so should be OK untill I get enough money aaside to get some new ones...

An other option I found is a guy specialised in fixing damaged ballscrew. May worth a try?

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=180485044327&ssPageName=ADME:X:RTQ:GB:1123


RNR

i2i
15-06-2012, 09:47 AM
wrong thread on the nut

rnr107
15-06-2012, 02:42 PM
wrong thread on the nut

Hummm.... I wonder, It should not be too dificult to make a new nut holder (with the right thread)?
Looks like a fairly simple shape and made of aluminium...


RNR

i2i
15-06-2012, 03:18 PM
is the original steel.??

Jonathan
15-06-2012, 04:15 PM
This is probably a bit far fetched, but I wonder if it would be possible to machine a thread on one of the cheap ballnuts from china? The grade of steel is clearly hard, but it does file so it may be possible to machine.

i2i
15-06-2012, 04:23 PM
that's the way i went for my 260.

rnr107
15-06-2012, 06:06 PM
is the original steel.??

Nope... It is a kind of aluminium alloy...



This is probably a bit far fetched, but I wonder if it would be possible to machine a thread on one of the cheap ballnuts from china? The grade of steel is clearly hard, but it does file so it may be possible to machine.

Hi Jonathan,
You would do that on a Lathe I guess. So would you first remove all the balls ?

RNR

Ricardoco
15-06-2012, 06:27 PM
Nope... It is a kind of aluminium alloy...




Hi Jonathan,
You would do that on a Lathe I guess. So would you first remove all the balls ?

RNR
Thanks for the link RNR, mine are steel and i would have opted for the repair but to be fair it really was fooked, i couldnt understand what was happening untill i had stripped everything down and by that time i had moved the Head up and down at least 20 times just to get it to go to the top so i could get the thing off... it was toast... i will replace all three with the threaded type like for like as i just dont have the time to mess around doing the other type with the machining..... I will let you know how i got on when its done but dont hold your breath as im building a gantry machine at the moment so it could be a while...

Rick

Woodfish
29-11-2017, 01:49 PM
Hi Laurent, I'm rebuilding a 260VMC, the electronics were replaced by Mach 3, but has been as its my first rebuild any other photos you have of it 'naked' would be of great help. Information on these things is as rare as rabbit horns and any that would help keep me from making mistakes would be most welcomed.
PS I have just rebuilt all three ballscrews, Scott Sayers from GMS Ball Ltd ([email protected], 01903 264601) was really helpfiul and extremely knowledgable.

rnr107
09-12-2017, 12:26 PM
Hi Laurent, I'm rebuilding a 260VMC, the electronics were replaced by Mach 3, but has been as its my first rebuild any other photos you have of it 'naked' would be of great help. Information on these things is as rare as rabbit horns and any that would help keep me from making mistakes would be most welcomed.
PS I have just rebuilt all three ballscrews, Scott Sayers from GMS Ball Ltd ([email protected], 01903 264601) was really helpfiul and extremely knowledgable.

Hi Scott,
Sorry for the delay... A bit busy these days. :-)
I sold this machine a while ago... But I may have some pictures or maybe I can answer some of your questions ?
What do you need? What's not working ?

RNR

Woodfish
06-02-2018, 12:59 PM
Really sorry for the tardy response, the end of last year and the start of this have been taken up with moving. For my retirement present I purchased a really nice 260VMC from a college in Essex. Following the retrofit of new electronics last year my winter project was to strip everything mechanical out and replace/rebuild all wearing parts.

I was getting on fine until my workshop was broken into. The Boxford (and others) were vandalised and all my neatly labelled takeaway boxes containing parts were just opened and thrown on the floor by some moron who nicked only my £20 digicam and a £30 laptop.

Unfortunately, these contained all of my stripping videos and photos. My memory is'nt as good as it was, so I'm just in need of photos or videos of the mechanical components to see which way things reassemble, as I seem to spend a lot of time doing things twice.

The words Boxford and information are rarely heard in the same sentence so anything would be appreciated, hours trawling various sites have given me little to help.
Regards
Woody

rnr107
15-02-2018, 09:47 PM
Really sorry for the tardy response, the end of last year and the start of this have been taken up with moving. For my retirement present I purchased a really nice 260VMC from a college in Essex. Following the retrofit of new electronics last year my winter project was to strip everything mechanical out and replace/rebuild all wearing parts.

I was getting on fine until my workshop was broken into. The Boxford (and others) were vandalised and all my neatly labelled takeaway boxes containing parts were just opened and thrown on the floor by some moron who nicked only my £20 digicam and a £30 laptop.

Unfortunately, these contained all of my stripping videos and photos. My memory is'nt as good as it was, so I'm just in need of photos or videos of the mechanical components to see which way things reassemble, as I seem to spend a lot of time doing things twice.

The words Boxford and information are rarely heard in the same sentence so anything would be appreciated, hours trawling various sites have given me little to help.
Regards
Woody

Hi mate,
Sorry to hear about your troubles... We do have morons in this world unfortunately.... :-(
Have you got an email address where I could send Photographs I have? (PM me, don't post your email address here it will be deleted)

RNR

trenchardb
26-04-2021, 11:07 PM
Hi Laurent,

I'm also rebuilding a VMC260, and I was wondering if you can remember if there is a way to remove the "rotating" spindle head from the Z axis slide? There appears to be a pivot in the centre of the spindle casting that allows it to rotate once you take out the 4 large bolts, but I don't seem to be able to separate the two from the central pivot? Do I need to remove the whole assembly including the slide to get to it, or is there some other way to remove it?

Any suggestions would be very gratefully appreciated!

Ben.

rnr107
27-04-2021, 07:34 AM
Hi Ben,
By "rotating" spindle head, do you mean the easy change head?
Could you post a few pictures?
Thank you,
Laurent

trenchardb
27-04-2021, 10:05 PM
Hi Laurent,

Many thanks for your reply. Sorry - I didn't describe it very well.. I hope that this picture helps... What I'm trying to do is separate the spindle housing casting from the Z axis slide (I need to replace the spindle bearings). I undo the 4 bolts around in the corners of the spindle housing casting, but there is still a pivot in the middle which allows the casting to rotate into a horizontal position. I can't see a way to remove the casting from that central pivot (if possible without having to remove the Z axis slide)?

29853

rnr107
28-04-2021, 07:57 AM
Hi Ben,
I think the only way to do that is to get the entire assembly off the machine.
There are screws behind the head.
Bring the head all the way up.
Look at my pictures on the first page of this thread you 'll see the cuts /groove in the column that show you the way to remove it is up. 😊

Laurent