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Washout
10-06-2014, 06:54 PM
Hi All,
.
My router is running OK at the moment (shortly about to convert a rotary table and tail stock/chuck into a 4th axis), but I find myself looking to do some steel parts for various projects.
.
What I am thinking of is a milling machine, which looking around for "bang for buck" is boiling down to these two:
.
http://www.ebay.co.uk/itm/AMADEAL-AMA30LV-Milling-Machine-MT3-Metric-/360422555676
.
http://www.warco.co.uk/milling-machines/38-gh-universal-milling-drilling-machine.html
.
Both are roughly similar in travel, spindle HP etc. and both would be MT3 variants (I have a fair few MT2/3 bits from my lathe) but the Warco from the limited views looks to be a bit more sturdily constructed.
.
Has anybody got experience of converting these to CNC and if I got another set of 3NM Nema 23 steppers, would they be up to the job or am I really looking at 34's? I can of course cut motor mounts etc. using my router and will probably use a box containing a pulley/belt for that purpose.
.
Also I have seen various posts talking of epoxy/aggregate mix to essentially make a milling bed and I'm wondering whether this might be a cheaper alternative to a conversion - I'm thinking 3 slabs in essence with ground linear guides/rails; 1 for the base, 1 for the X and 1 for the Y - Z I haven't considered yet.
.
In terms of timing its not urgent, so likely towards the back end of this year for either option, but obviously the conversion will be quicker in theory to complete.
.
Opinions?
.
Cheers
.
.
Chris
.
PS. I forgot to mention if I can get away with Nema 23's then I could use my existing control box - just swap the XLR connectors before using each machine (and make the necessary changes in MACH of course).

njhussey
11-06-2014, 09:57 AM
Hi All,
.
My router is running OK at the moment (shortly about to convert a rotary table and tail stock/chuck into a 4th axis), but I find myself looking to do some steel parts for various projects.
.
What I am thinking of is a milling machine, which looking around for "bang for buck" is boiling down to these two:
.
http://www.ebay.co.uk/itm/AMADEAL-AMA30LV-Milling-Machine-MT3-Metric-/360422555676
.
http://www.warco.co.uk/milling-machines/38-gh-universal-milling-drilling-machine.html
.
Both are roughly similar in travel, spindle HP etc. and both would be MT3 variants (I have a fair few MT2/3 bits from my lathe) but the Warco from the limited views looks to be a bit more sturdily constructed.
.
Has anybody got experience of converting these to CNC and if I got another set of 3NM Nema 23 steppers, would they be up to the job or am I really looking at 34's? I can of course cut motor mounts etc. using my router and will probably use a box containing a pulley/belt for that purpose.
.
Also I have seen various posts talking of epoxy/aggregate mix to essentially make a milling bed and I'm wondering whether this might be a cheaper alternative to a conversion - I'm thinking 3 slabs in essence with ground linear guides/rails; 1 for the base, 1 for the X and 1 for the Y - Z I haven't considered yet.
.
In terms of timing its not urgent, so likely towards the back end of this year for either option, but obviously the conversion will be quicker in theory to complete.
.
Opinions?
.
Cheers
.
.
Chris
.
PS. I forgot to mention if I can get away with Nema 23's then I could use my existing control box - just swap the XLR connectors before using each machine (and make the necessary changes in MACH of course).

Hi Chris,

I've just got the WARCO Major GH Milling machine and so far I think it's great, done a few little jobs on it....admittedly I've nothing to compare it against as I've never had a milling machine before!! I'll be converting it to CNC in the near future, the only real challenge I think will be the Z axis...still looking at that to see how it can be done without too much cutting and carving!

Washout
11-06-2014, 10:22 AM
Thanks Neil,
.
If you get some time could you post a few pictures of the Warco? I'm interested in how the leadscrews? and manual handles are mounted. Also is the Z axis power fed or again manual?
.
Cheers
.
.
Chris

Neale
11-06-2014, 10:56 AM
After looking at a few of the machines around (including all the Warco mills in their showroom) I went for the VMC. One main reason was height - the VMC has the main drive motor hanging down rather than sticking up and my workshop has limited headroom. The rise-and-fall knee looks like a reasonable proposition as part of a CNC conversion but not sure if that would be easier or harder than on the GH. GH capacity is a little larger, but the VMC has more iron in it (going by published weights) which might count for something! If you include a stand, then the VMC is a little cheaper, and the saving would buy you an R8 ER32 collet set. I've only had 2MT tooling until now, so would have needed to add 3MT or R8 collets, chuck, etc, and R8 is much nicer to use than MT shanks. Looking at the Warco site, in fact, they only seem to list the GH with R8 anyway.

Dean jeffery
11-06-2014, 12:38 PM
Subed I'm pretty much in the same boat

Sent from a GS4 using tapacrap

njhussey
11-06-2014, 02:14 PM
Thanks Neil,
.
If you get some time could you post a few pictures of the Warco? I'm interested in how the leadscrews? and manual handles are mounted. Also is the Z axis power fed or again manual?
.
Cheers
.
.
Chris

Hi Chris,

I'll take some pics in a bit and put them on here. The Z is manual feed....

njhussey
12-06-2014, 02:09 PM
http://img.tapatalk.com/d/14/06/12/jejugusa.jpg

http://img.tapatalk.com/d/14/06/12/mepu5ebu.jpg

http://img.tapatalk.com/d/14/06/12/ama5yzub.jpg

http://img.tapatalk.com/d/14/06/12/me7asyvu.jpg

http://img.tapatalk.com/d/14/06/12/amasupym.jpg

http://img.tapatalk.com/d/14/06/12/sezu5uqy.jpg

Hope these are of use?

Washout
12-06-2014, 02:17 PM
Thanks Neil

Those are perfect and looking at the lead screw mounts/bearing blocks I think those will be fairly easy to adapt to ball screws/steppers - clearance underneath looks a little tight, but I guess a custom coupling can be made also.

I'm guessing that a 1605 size would fit in there?

I'm 90% sure I'll be buying the same machine or the dovetail Z axis variant.

Clive S
13-06-2014, 01:12 AM
I converted this mill about 9 months ago using the existing screws. with 3.1nm motors and now
I am just changing the lead screws to ball screws if this helps on my Warco WM-18 mill I will be use 1605 screws.

I machined a slot out under the X table with my router very slowly 1mm DOC 200mm/min with a 6mm carbide 4 flute at 5500 rpm.

The yellow endplate on the X table will have the boss taken off and the hole opened out to 42mm, then a boss will be made to insert into the 42mm hole.

The boss will then have a 32mm hole cut out for the AC bearings offset by 3 mm to bring the screw up into the machined slot under the X table by that amount.
12572


1256212563125651256612567125681256912571
The Y screw will fit using the original boss just opened out to 32mm for the AC bearing.
Then of course there is the Z to think about. ..Clive

Washout
13-06-2014, 10:01 AM
Excellent pics Clive, thanks (do you have a build log?)

I'm assuming the slot in the bed and moving the replacement ballscrew up is needed to clear the Y axis carriage below it? I was rather hoping to get away without modding the main milling structures (beds etc.)

BTW - when you milled that slot were you using a 2.2Kw Spindle on your router? I've not tried running mine that slow as I thought you got torque issues below 6000rpm?

The Z axis looks like it could be converted by using a new top plate/bearing holder with a stepper/belt arrangement essentially strapped to the back of the column and abandon the "differential/bevelled gears" from the original?

Looking forward to seeing more progress shots.

Clive S
13-06-2014, 11:41 AM
The Z axis looks like it could be converted by using a new top plate/bearing holder with a stepper/belt arrangement essentially strapped to the back of the column and abandon the "differential/bevelled gears" from the original?
This is how it was converted with the original screws using the original bolt holes for the top plate. You can see the arrangement for the Y axis with the motor under the x carriage and the X Motor using the holes on the yellow endplate.

Regarding the spindle it is the 2.2Kw W.C. I did try it at 5K but was happier with 5.5K I have my spindle set up so that it won't go down past 3.3K I cut the slot with no issues.

I suspect that all beds are different underneath so the clearance will differ. I will post when I get the x screw in place but I have to get them first. ..Clive


12575125741257312576

Washout
13-06-2014, 02:14 PM
Excellent (starts looking at the budget for earlier purchase :) ).

I'll have to play with my WC 2.2Kw on my router also given your experience and see what can be achieved, though it will have to wait until I have my rotary axis working.

njhussey
13-06-2014, 02:26 PM
Clive, did you not consider using a screwed ballnut instead of the flanged one?

12579

I'm thinking of using one as I reckon I'll get away with not having to machine the bed...bit of threadlock and Bob's your uncle etc.

Clive S
13-06-2014, 03:16 PM
Clive, did you not consider using a screwed ballnut instead of the flanged one?

12579

I'm thinking of using one as I reckon I'll get away with not having to machine the bed...bit of threadlock and Bob's your uncle etc.Not quite sure what you mean by that, The flanged boss I am using is to enable me to use the original end plates on the X bed by machining the stub off then boring the 40 mill hole out to 42mm then the the new boss can be fitted with the bearings offset by the 3mm I need to get the screw in.

The flange is in the centre of the bearing housing ie stub both ends.

Do you have a link to that screwed nut? ..Clive

njhussey
13-06-2014, 03:32 PM
It's one from Zapp, if you look on the ball screw page it's down the bottom.

I presume that you're using the standard flanged ballnut like the below?

http://img.tapatalk.com/d/14/06/13/y7amuge2.jpg

I was going to see if I could get away with one i could screw in to a 25mm (or whatever width) piece of steel that will replace the tapped existing nut.

njhussey
13-06-2014, 03:37 PM
This in the inside of the front of my mill, was thinking of opening the hole where the indicator goes through the bottom, rap it for a 1605 screwed ballnut and use a 1605 ballscrew with custom bearing ends.


http://img.tapatalk.com/d/14/06/13/hanuquja.jpg

http://img.tapatalk.com/d/14/06/13/amare2yn.jpg

http://img.tapatalk.com/d/14/06/13/9une6a8e.jpg

Clive S
13-06-2014, 03:56 PM
http://img.tapatalk.com/d/14/06/13/y7amuge2.jpg[/IMG]

.Neil Yes that is the type of nut, but the problem is the width of the body (round bit) hence the channel I had to cut in the bed. I will make the housing for the nut with the lug on it to bolt to the original place. Yours is a bigger machine and the Z arrangement is different. Thanks for the pics. ..Clive

Jonathan
13-06-2014, 06:18 PM
Double nuts are a good idea for a milling machine - i.e. DFU1605 not SFU1605.

njhussey
13-06-2014, 07:28 PM
Would two singles screwed into each side of the plate/bracket be ok?

Washout
13-06-2014, 10:21 PM
Hi Jonathan
.
Can you explain in short words for an old duffer like me how a double nut works?
.
My guess is that there are "tensioned" in opposite directions against each other and therefore cancel out any play no matter which direction of rotation is used (can't quite visualise how though).
.
Cheers
.
.
Chris

Jonathan
14-06-2014, 02:03 AM
My guess is that there are "tensioned" in opposite directions against each other and therefore cancel out any play no matter which direction of rotation is used (can't quite visualise how though).

Near enough. I recommend reading Robin's build log (http://www.mycncuk.com/threads/651-Warco-Major-CNC-build-log?highlight=robin+warco+major) as he dismantled some, so you can easily see how it works ... or can be improved with springs (which I've now copied on 3 machines but with separate nuts).

JAZZCNC
14-06-2014, 11:09 AM
I machined a slot out under the X table with my router very slowly 1mm DOC 200mm/min with a 6mm carbide 4 flute at 5500 rpm.

BUT BUT BUT CLIVE dont you know Routers can't Machine Cast Iron they must only EVER be used for cutting compressed paper according to ROBINS law. :whistle:

Clive S
14-06-2014, 11:24 AM
BUT BUT BUT CLIVE dont you know Routers can't Machine Cast Iron they must only EVER be used for cutting compressed paper according to ROBINS law. :whistle:
Very sorry about that, I will never ever do it again :hysterical: ..Clive

JAZZCNC
14-06-2014, 11:32 AM
Very sorry about that, I will never ever do it again :hysterical: ..Clive

You bloody well better do it again mate otherwise don't bother ringing me anymore.! . :devilish:

Clive S
14-06-2014, 11:38 AM
You bloody well better do it again mate otherwise don't bother ringing me anymore.! . :devilish:
Eh Eh OK boss. I might try titanium and see how that goes. :playful:

Washout
14-06-2014, 12:32 PM
Eh Eh OK boss. I might try titanium and see how that goes. :playful:

How hard can it be? ;-)

JAZZCNC
14-06-2014, 02:39 PM
Eh Eh OK boss. I might try titanium and see how that goes. :playful:

Ok and I'll get the tissues ready and my book of sympathy words:hysterical:. .

njhussey
10-07-2014, 03:19 PM
After using the mill (and lathe) to make a one off spacer and a couple of other bits I now wish I'd got a mill with a dovetail Z axis and not the round column!! We've got a BILZ tapping head that requires the headstock to be moved up to use and as soon as you move it you lose position so you have to go back to finding your centres again which is a right royal PITA. I'm going to get a cheap laser pointer and mill a 1mm notch in some white plastic and attach the laser pointer to the mill head pointing back at the wall at the plastic. Hopefully (if the plastic is truely vertical) then I can keep the head square. I've discovered that the rack for the head is only wedged top and bottom on the column and not secured in any way so it can flex as much as it likes.....crap design but I guess you get what you pay for. I can see the machine coming apart and the rack being drilled and tapped so it is fixed to the column to stop some of this flexing. Trouble is we seem to have sold a few "one offs" recently so can't do anything to it yet...

Pics of the spacer, the DRO is brilliant for doing PCD's...makes it easy to drill bolt holes.

127581275712756

njhussey
29-07-2014, 11:03 AM
Fitted a DRO to the Z axis just now...

http://img.tapatalk.com/d/14/07/29/saba2aba.jpg

http://img.tapatalk.com/d/14/07/29/yradu5er.jpg

http://img.tapatalk.com/d/14/07/29/5edytybu.jpg