Author Topic: Chester 626 mill CNC Conversion  (Read 213331 times)

Rob.Wilson

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Re: Chester 626 mill CNC Conversion
« Reply #525 on: March 12, 2013, 01:09:37 PM »
 :lol: :lol: :lol: sand and see sea is are the wrong colour  :lol:

PM and Email sent


Rob

edited due to being thick
« Last Edit: March 12, 2013, 02:55:13 PM by RobWilson »

Offline John Stevenson

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Re: Chester 626 mill CNC Conversion
« Reply #526 on: March 12, 2013, 02:48:38 PM »
Dear Charles Atlas,
I have finished your course, now send me the muscles........................
John Stevenson

Offline lockstocknbarrel

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Re: Chester 626 mill CNC Conversion
« Reply #527 on: March 13, 2013, 03:42:44 AM »
Who's Charles Atlas. :Doh:

Is he the guy who put the globe into a book.
Regards Beagles
Kindest Regards
Beagles............
Dave Weir

Rob.Wilson

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Re: Chester 626 mill CNC Conversion
« Reply #528 on: April 01, 2013, 02:14:33 PM »
Right I am back on with this project .

Sat down and made a list of what needs to be done , fairly long list  :(  Thought right lets get the gib adjusters sorted , original ones have slots , really poor idea as you cant get a screwdriver in to adjust the gibs up .



Easy wee project ,,,,,,,,,, mmmmmmm then the crap starts . The pockets are not round ,or concentric with the M6 Tapped hole , some are tapped 20mm and others are 50mm . One is not even fookng straight . bastards.

 


So I made up a couple of temp adjusters and decided to trial fit the knee.





And as you can see the gib is to long .the lower adjuster is in the pocket .


I need to trim 1/2 of the knee gib so that the adjuster will be in the pocket



Y axis gib needs work to nearly bottoms out in one pocket .






So I thought I would just do a quick test to see how the gibs fit the ways , lost of bad language &^^%$ ((*& &**)))_^%"(*&

 

well they touch in a few places  :doh:   ,SO I either mess on trying to fix the crappy tapered gibs , or remachine the ways and fit standard /parallel gibs .


Rob   







Offline John Stevenson

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Re: Chester 626 mill CNC Conversion
« Reply #529 on: April 01, 2013, 02:22:29 PM »
Use the opportunity to fit Turcite  ?

I have this on my new mill and it's awesome how smooth and easy it is.
John Stevenson

Offline NickG

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Re: Chester 626 mill CNC Conversion
« Reply #530 on: April 01, 2013, 02:52:22 PM »
Are they really that bad? Still
Might be better than standard gibs. So you think it's the gibs or the slide ways that are bad though?
Location: County Durham (North East England)

Rob.Wilson

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Re: Chester 626 mill CNC Conversion
« Reply #531 on: April 01, 2013, 03:44:14 PM »
Thats one road John , just dont fancy buying a 50 meter roll  :palm:

Are they really that bad? Still
Might be better than standard gibs. So you think it's the gibs or the slide ways that are bad though?

 :lol: :lol: What photos were  you looking at Nick  :scratch:   ,, the gibs are only making contact  were the light spots are , not the blue area   :palm: ways are fine its the gibs that are naff


Rob


Offline doubleboost

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Re: Chester 626 mill CNC Conversion
« Reply #532 on: April 01, 2013, 04:09:54 PM »
Pleased to see you are back at it Rob
I spent hours lapping mine to a decent fit
Just about need to start with a angle grinder
Mine is built a bit better than yours was
No doubt when you are finished it will be the best 626 in existence
John

Offline NickG

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Re: Chester 626 mill CNC Conversion
« Reply #533 on: April 01, 2013, 04:22:03 PM »
I though it was contact where the blue was! May be easier to make new tapered gibs then? Easier to make a matching pair that way?
Location: County Durham (North East England)

Offline micktoon

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Re: Chester 626 mill CNC Conversion
« Reply #534 on: April 01, 2013, 05:06:16 PM »
 Hi Rob , glad to see the project is back on again , its amazing what altering the clocks does, its amazing that them gibs only make contact at them points, you would think any random bit of flat bar would be better than that  :palm: :palm: ......still look on the bright side, at least your not rebuilding a go kart for someone  else :palm: :palm: :bang: :bang: lol
 Looking forward to seeing the new gibs whatever way you decide to do it.
  Cheers Mick

Offline John Stevenson

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Re: Chester 626 mill CNC Conversion
« Reply #535 on: April 01, 2013, 05:27:44 PM »
Rob,
Try Brain caddy at Slideway services, Coventry, he'll sell you just the amount you need.
John Stevenson

Offline Pete.

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Re: Chester 626 mill CNC Conversion
« Reply #536 on: April 01, 2013, 07:47:51 PM »
Those gibs fit better'n mine. My cross-slide even rocks on it's ways :(

Rob.Wilson

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Re: Chester 626 mill CNC Conversion
« Reply #537 on: April 04, 2013, 12:38:21 PM »
Rob,
Try Brain caddy at Slideway services, Coventry, he'll sell you just the amount you need.

Cheers John , I am going to re scrape the gibs for now , if it goes tits up I will be giving him a call .

Those gibs fit better'n mine. My cross-slide even rocks on it's ways :(

Bummer Pete ,,,,,,,,,,,,is it really bad , what make of machine ?


Well I think I could have my gibs all wrong , They must be a new type of AIR GLIDE GIB because having decided to re scrape the gibs to fit the ways , first thing to do is check the tapered side to make sure its flat ,well what do you no , the bastard things only touch in three four places , blue area's are the touch .

Top class work



Made a start on one last night ,1/2 hour of scraping , getting there .



Rob

 

Offline AdeV

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Re: Chester 626 mill CNC Conversion
« Reply #538 on: April 04, 2013, 02:04:52 PM »
Hmm, wouldn't it have been quicker/easier to give it a quick lick on your surface grinder before scraping?
Cheers!
Ade.
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Offline NickG

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Re: Chester 626 mill CNC Conversion
« Reply #539 on: April 04, 2013, 03:09:02 PM »
I was thinking that but how do you get the angle right? Couldn't you rub them on wet & dry on a surface plate?
Location: County Durham (North East England)

Rob.Wilson

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Re: Chester 626 mill CNC Conversion
« Reply #540 on: April 04, 2013, 03:11:12 PM »
A couple of things with that plan Ade  :)


One . they are tapered gibs so I would need an adjustable mag chuck which I dont have , on the list to make .

Two . And still even if I did have a tiling mag chuck with long slender work you would still need a flat surface to start with ie the face that would be stuck to the chuck ,  because if it was bowed in any way the mag chuck would pull it flat and after grinding when the chuck was released it would spring back , ending  up with a bowed ground surface . 

Rob

Offline micktoon

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Re: Chester 626 mill CNC Conversion
« Reply #541 on: April 04, 2013, 03:51:30 PM »
Hi Rob ,
         I am sure you will get there in the end, like NickG says to get one surface flat you would think that wet & dry on flat surface would speed things up as a starting point ? It makes you wonder what the hell they use to make this stuff in the first place , it must just be drilling with hand held drills and flat surfaces done with hand file, even the bits you can see have not even been done to a visually good standard on some new stuff ................ which as you are finding out makes you wonder what the bits you can not see are like.......... sad really to think that a 'modern' machine has such low standards  :palm:
   At least it will be brought back to standards of the good old days once you have finished with it Rob  :thumbup: , keep up the good work :drool:

  Cheers Mick
 

Rob.Wilson

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Re: Chester 626 mill CNC Conversion
« Reply #542 on: April 04, 2013, 04:21:02 PM »
Hi Mick and Chris ,,,,,, First off I am not a big fan of emery paper in all its forms for sizing a part , its ok for rubbing down for painting, cleaning off rust , polishing and blending  . 

Ok you  place your sheet of emery on a surface plate ,rub the part back and fourth , round and round .

How do you keep an equal pressure on the part ?

How do you control were material is removed ?

And after that I bet the part is still not flat .

Would rather just scrape the surface flat  :)

Rob


Wile on the subject weee rant , rubbing something back and fourth on a sheet of emery paper is NOT LAPPING ,  :bang: :bang: another  engineering term that has been bastardized .

Offline loply

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Re: Chester 626 mill CNC Conversion
« Reply #543 on: April 04, 2013, 05:40:02 PM »
Close analysis of the gibs on various cheap machines has convinced me that they finish them using a soft fibre disc on an angle grinder,  possibly just eyeballing it to a surface plate as they go. I can't imagine why they would do this in preference to the machined finish that was surely present previously?

Or were they never machined, and simply went from a casting to 'scraped with an angle grinder' in one go?

Offline S. Heslop

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Re: Chester 626 mill CNC Conversion
« Reply #544 on: April 04, 2013, 08:08:09 PM »
Hi Mick and Chris ,,,,,, First off I am not a big fan of emery paper in all its forms for sizing a part , its ok for rubbing down for painting, cleaning off rust , polishing and blending  . 

Ok you  place your sheet of emery on a surface plate ,rub the part back and fourth , round and round .

How do you keep an equal pressure on the part ?

How do you control were material is removed ?

And after that I bet the part is still not flat .

Would rather just scrape the surface flat  :)

Rob

I'm pleased to hear you say this since it's something that never made much sense to me.

Offline Davo J

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Re: Chester 626 mill CNC Conversion
« Reply #545 on: April 04, 2013, 11:16:19 PM »
Hi Rob,
I am still watching with interest, great work.
I am just wondering why you never notched the gib to suit your new adjusters like most mills come like from the factory.
All the machines I have and have seen have this notch.
With cutting it off you have lost 1/2 inch of support on that axis.

Dave

Rob.Wilson

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Re: Chester 626 mill CNC Conversion
« Reply #546 on: April 05, 2013, 11:40:39 AM »
Hi there Dave , good to see your on the case  :)



So I made up a couple of temp adjusters and decided to trial fit the knee.


Yes there are many types of gib adjusters , I am still undecided what type to use . Even so if I were to go  for a slotted type the slot would be machined  after the gibs were scraped  ,as with tapered gibs /any tapered item when fitting /removing material ,a small amount of material  removed can move the part a fare way laterally . So fit the gib then mark the position for the slot .

Something I will have to be careful about ,pondering just making new gibs .


Close analysis of the gibs on various cheap machines has convinced me that they finish them using a soft fibre disc on an angle grinder,  possibly just eyeballing it to a surface plate as they go. I can't imagine why they would do this in preference to the machined finish that was surely present previously?

Or were they never machined, and simply went from a casting to 'scraped with an angle grinder' in one go?

I would say your observations were bang on  :thumbup:


Cheers Rob 

 

Offline Pete.

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Re: Chester 626 mill CNC Conversion
« Reply #547 on: April 05, 2013, 12:52:00 PM »

Two . And still even if I did have a tiling mag chuck with long slender work you would still need a flat surface to start with ie the face that would be stuck to the chuck ,  because if it was bowed in any way the mag chuck would pull it flat and after grinding when the chuck was released it would spring back , ending  up with a bowed ground surface . 


Yeah and guess who found this out when he tried to make a triangular 90-40-50 straight-edge from a large sash weight last week. I set my tilting table up and dialled it in carefully on the mill, cut two sides, then cut the third and stood back to admire my perfectly-formed bent-edge :D

Quote
Bummer Pete ,,,,,,,,,,,,is it really bad , what make of machine ?

It's an old Warco round-column. Hasn't seen much use and I guess that's because the previous owners also found out how crap it was before giving up.

I'm now using it as a test-mule to practice my scraping. even if I ruin it (hardly likely) I'm only out 150.

Offline AdeV

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Re: Chester 626 mill CNC Conversion
« Reply #548 on: April 05, 2013, 04:39:02 PM »
A couple of things with that plan Ade  :)


One . they are tapered gibs so I would need an adjustable mag chuck which I dont have , on the list to make .

Two . And still even if I did have a tiling mag chuck with long slender work you would still need a flat surface to start with ie the face that would be stuck to the chuck ,  because if it was bowed in any way the mag chuck would pull it flat and after grinding when the chuck was released it would spring back , ending  up with a bowed ground surface . 

Rob

See, I knew there'd be a good reason. Or a reason at least  :lol: And yours definitely fall into the "good one" category...

I guess the chrome paint gets put away when you're scraping?  :lol:
Cheers!
Ade.
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Offline Davo J

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Re: Chester 626 mill CNC Conversion
« Reply #549 on: April 05, 2013, 10:02:00 PM »
Thanks Rob, I didn't catch the temp bit, so your going to make new gibs.
I think for cnc you would be better off sticking with the taper gibs.

Dave