Build Thread Time to strengthen and upgrade....


Results 1 to 19 of 19

Thread: Time to strengthen and upgrade....

  1. #1
    Member
    Join Date
    Jun 2013
    Posts
    443
    Downloads
    0
    Uploads
    0

    Default Time to strengthen and upgrade....

    Its the never ending story. Start with Mark 1 to now..... Mark 8(ish) ha

    I posted a thread looking to sort some vibration issues only to decide to upgrade from the round SBR rails on the X and Z. Also make a new Z axis assy. The original was your typical beam gantry with the SBR rails attached to the front of the beam.

    For the X axis assy, I am thinking about installing a HG 30mm rail on the lower front of the gantry beam. And instead of just above it on the same plane, installing the second X rail on the top plane of the gantry beam. Sample pic attached. I feel this would give more support any thoughts otherwise?

    A new Z axis spindle assy would be a 20mm mild steel plate backing. With the spindle sitting on a further 20mm mild steel plate running up and down on HG 30 rails. It will be heavy, rigid, and solid.

    Similar Threads:
    Attached Thumbnails Attached Thumbnails Time to strengthen and upgrade....-gantry-concept2-jpg   Time to strengthen and upgrade....-gantry-concept-jpg   Time to strengthen and upgrade....-13-jpg  


  2. #2
    Member peteeng's Avatar
    Join Date
    Jul 2018
    Location
    dum dum
    Posts
    6248
    Downloads
    0
    Uploads
    0

    Default Re: Time to strengthen and upgrade....

    Hi Boydage - Chase that Grail! I have not used round rail before. I'm about to order some for a machine that uses up some of my surplus parts. Do the round rail cars have some sort of preload/clearance adjustment as they wear? Cheers Peter



  3. #3
    Member
    Join Date
    Jun 2013
    Posts
    443
    Downloads
    0
    Uploads
    0

    Default Re: Time to strengthen and upgrade....

    Quote Originally Posted by peteeng View Post
    Hi Boydage - Chase that Grail! I have not used round rail before. I'm about to order some for a machine that uses up some of my surplus parts. Do the round rail cars have some sort of preload/clearance adjustment as they wear? Cheers Peter
    Whats cool is I am sure there is at least one thing still on my machine that was there day 1 ha. Hey yes the round rails do have a couple of grub screws that tighten the ball circuits - not sure how they do it - probably not that clever. But in all reality, I am only upgrading to chase that vibration dragon. If I was only using my machine for timber it would be super. I have not actually measured the rails to see if they are worn they are well hardened. I think where they fall over is the lack of lateral support ie the carriage can roll. Rgds B



  4. #4
    Member peteeng's Avatar
    Join Date
    Jul 2018
    Location
    dum dum
    Posts
    6248
    Downloads
    0
    Uploads
    0

    Default Re: Time to strengthen and upgrade....

    Hi B - That's the beauty of the rails they aren't as fussy as a square rail that will lock up if its foundation is a little off square. Strengths are weaknesses, weaknesses are strengths... Peter



  5. #5
    Member
    Join Date
    Jun 2013
    Posts
    443
    Downloads
    0
    Uploads
    0

    Default Re: Time to strengthen and upgrade....

    So I have been thinking about this Z axis I am going to make. I am not a design engineer but feel that a Z axis needs to be mass heavy, with good strong attachments. I quite like the idea of the counter weight but dont plan to use my machine for steel machining. Accurately built then installed onto the gantry as perfectly as possible. I do believe its almost impossible to hand measure and manufacture the parts I need out of steel unless I either pay someone to cut them out and machine them flat, or I make them out of solid alloy. Even hole placement - I hate marking out holes.

    I was thinking about getting the major 2 pieces cut out of mild steel plate - this is the cheap part. But then am considering laminating a 6mm aluminum skin cut to the same shape on each side of the mild steel. This, I would be able to machine myself flat, and pilot drill the holes for placement of rails etc. Laminating I would use proper adhesive and once machined also screw fixings. I need to think about this more.

    Is this a weird idea? I guess its worth a go. My machine is currently accurate and I would like to use it as much as possible for this upgrade. I just dont think alloy by itself is hard or rigid enough to manufacture a cnc router out of. I need to use steel, but need to be able to work with it. Hey and thanks for the headsup re the setup of the square rails that will make me focus even more on accuracy.



  6. #6
    Member peteeng's Avatar
    Join Date
    Jul 2018
    Location
    dum dum
    Posts
    6248
    Downloads
    0
    Uploads
    0

    Default Re: Time to strengthen and upgrade....

    Hi B - Can't you use your current machine to pilot or start to centre drill the holes? Or is this what you are suggesting in the lamination? The steel is best used on the outside not the inside. If your current machine is good for aluminium then go thick aluminium. Steel is only an advantage if it has to be thin. If you can make things thicker or with flanges then aluminium will win in Terms of stiffness. See calculation attached. Adding flanges improves it further again, making it a box even better. Peter

    calculation shows that a 28mm thick Al plate is same rigidity as a 20mm steel plate. This is because the geometry gains stiffness to the 4th power vs the material stiffness which is linear. So a thicker al plate is lighter and stiffer then its steel version.

    Re: Rail on top and bottom front: Rail foundations have to be parallel. They are conventionally done on the same face so the foundations can be machined in one op guaranteeing the faces are parallel and same height. With the proposed top rail it MUST be level. Then the bottom rail can be made parallel to it in the vertical plane. But how do you adjust it in the horizontal plane? You can wiggle the top rail till its true if the surfaces are close enough... In my experience its the bottom rail/car that gets abused the most. Its the car that's closest to the tool so gets the maximum impact in crashes and maximum load in heavy cuts. Especially with a square car as it supports moments. The round rail will distribute these forces between the cars as it can roll slightly. If your confident of getting the rails parallel then put the rails top and bottom of the gantry. This has the advantage of bolt access to the cars. Its really good to decouple the bolting access of the tool plate and saddle. That's one reason I put the rails on top of the gantry so the bearing bolt access is opened up.... Peter

    Attached Thumbnails Attached Thumbnails Time to strengthen and upgrade....-tool-plate-jpg  
    Last edited by peteeng; 06-03-2022 at 05:24 AM.


  7. #7
    Member
    Join Date
    Jun 2013
    Posts
    443
    Downloads
    0
    Uploads
    0

    Default Re: Time to strengthen and upgrade....

    Morning! That last post is huge for me. Thankyou. I was talking to our design engineer yesterday on an unrelated project about deflection and thought "I must study that more to know" I truly honestly thought steel was so much harder/rigid than alloy that it was the only way to go. I would have been able to pilot drill the holes with my machine but not face it to proper flat which I can with alloy. I have been talking to several engineering companies here locally and around the country and its not going to be cheap to have those parts made. Absolutely. Yes I can use some alloy 6061. A couple of pieces of plate 30mm thick or even more would still be cheaper than having it made for me. And - I get to make it myself. Also looks better too unless its stainless. OK I will put that to design and add in some strengthening. Weight was just another item in my head ie do I need it to absorb the cutting chatter? Another point exposing my lack of design knowledge.

    Noted about the X rails. I was actually hoping to find someone who can grind flat two decent size bars to sit under the 1450mm long X rails. Although they would still be separate and need correct placement. But that portion has not been easy here in NZ. Lots of companies with advertising saying they can grind huge size material only to find they cannot. My thoughts were to manufacture a set of jigs to install the rail on the top of the gantry. Although I would do that either way. With your info in mind I will think more. What I do see on my current home build setup is the round rails are spaced properly apart but in places one is higher than the other causing the spindle to travel forward and back as it goes past. Not much about 0.5mm over the total length but in reality thats a lot. The gantry is from build V2 lol.



  8. #8
    Member peteeng's Avatar
    Join Date
    Jul 2018
    Location
    dum dum
    Posts
    6248
    Downloads
    0
    Uploads
    0

    Default Re: Time to strengthen and upgrade....

    Hi B - weight does not absorb chatter. Chatter is principally lack of stuiffness as they say across the ditch So always max the stiffness/rigidity. Peter



  9. #9
    Member ardenum's Avatar
    Join Date
    Nov 2020
    Posts
    361
    Downloads
    0
    Uploads
    0

    Default Re: Time to strengthen and upgrade....

    Quote Originally Posted by boydage View Post
    Morning! That last post is huge for me. Thankyou. I was talking to our design engineer yesterday on an unrelated project about deflection and thought "I must study that more to know" I truly honestly thought steel was so much harder/rigid than alloy that it was the only way to go. I would have been able to pilot drill the holes with my machine but not face it to proper flat which I can with alloy. I have been talking to several engineering companies here locally and around the country and its not going to be cheap to have those parts made. Absolutely. Yes I can use some alloy 6061. A couple of pieces of plate 30mm thick or even more would still be cheaper than having it made for me. And - I get to make it myself. Also looks better too unless its stainless. OK I will put that to design and add in some strengthening. Weight was just another item in my head ie do I need it to absorb the cutting chatter? Another point exposing my lack of design knowledge.

    Noted about the X rails. I was actually hoping to find someone who can grind flat two decent size bars to sit under the 1450mm long X rails. Although they would still be separate and need correct placement. But that portion has not been easy here in NZ. Lots of companies with advertising saying they can grind huge size material only to find they cannot. My thoughts were to manufacture a set of jigs to install the rail on the top of the gantry. Although I would do that either way. With your info in mind I will think more. What I do see on my current home build setup is the round rails are spaced properly apart but in places one is higher than the other causing the spindle to travel forward and back as it goes past. Not much about 0.5mm over the total length but in reality thats a lot. The gantry is from build V2 lol.
    try uploading your part to xometry, I couldn't find a cheaper machining and I've been looking for over 2 years now.

    - - - Updated - - -

    Last edited by RaderSidetrack; 06-04-2022 at 12:17 PM. Reason: remove duplicate quote and text


  10. #10
    Member
    Join Date
    Jun 2013
    Posts
    443
    Downloads
    0
    Uploads
    0

    Default Re: Time to strengthen and upgrade....

    Hi Peter. Ok this is all good stuff. I will draw something up and I think the hardest part is going to be the longer X rails on the gantry getting them correct. I will draw up a concept and post it after looking at what plate 6061 is available in. Gee I guess there is nothing stopping me from machining it ( Z axis assy) out of a couple of pieces of 32mm stock. Is 40mm too much? I have a large machine, future proofing is always a good thing and why not. I was thinking about the spindle and how it is mounted, currently it is inside a box section extrusion supplied like that. Its probably fine, not sure, I will check it out.

    Hey thanks? Really its been fantastic on several platforms. Even with the use of alloy now I am still going to be saving some cash. Boyd



  11. #11
    Member peteeng's Avatar
    Join Date
    Jul 2018
    Location
    dum dum
    Posts
    6248
    Downloads
    0
    Uploads
    0

    Default Re: Time to strengthen and upgrade....

    Hi Boyd - Can never be too stuiff. Peter



  12. #12
    Member
    Join Date
    Jun 2013
    Posts
    443
    Downloads
    0
    Uploads
    0

    Default Re: Time to strengthen and upgrade....

    Sorry Arbenden I missed your post and remember I am in New Zealand where the options are as small. Hey so I had a bit of a play around this weekend with a new Z. All built of of 30mm 6061 ex 31.75mm . I kept going back to my original design built with 10mm and 16m plate - it is an oldie but worked to a point. But the main lower fulcrum is always a weak point or seems to be under a lot of stress. I kept putting further bracing on it and probably still will. More stiffeners. I took them back off for the example drawing.


    This time though I thought about putting the linear rails on the spindle mounting plate and that didnt work as well. So I have ended up installing a couple of main HG rails and carriages on the outter sides of the Z axis. And have included a set of shorter HG rails to move with the spindle with the addition of two carriages bolted to the rear stationary plate. Felt the rails in the center of the rear of the spindle mounting plate would stiffen it and add support throughout the front of the assembly as also transfer or share some of the forces. I have made everything out of (finished size) 30mm 6061. It took a bit of playing around to get the dimensions to work, and have lost about 90mm of travel. But I like the idea.

    I do expect it to be difficult to move with all these carriages so will use a Nema 34 in the place of the current Nema 24 on the original. Oh and I still need to design a mount for the Nema 34 that is sitting in space but am sure you will get the idea. And what the main advantage is about all this? I can build it myself. Might not be perfect, but, can only do my best.

    Just saw Top Gun with my kids - worth a look. B

    Attached Thumbnails Attached Thumbnails Time to strengthen and upgrade....-new-z-jpg  


  13. #13
    Member
    Join Date
    Jun 2013
    Posts
    443
    Downloads
    0
    Uploads
    0

    Default

    I am not a design engineer only making things as strong and rigid as I think they should be. Its been a while since I posted because I decided to machine a new Z axis but have also made a new X axis to screw onto my gantry.

    I found a 20mm thick piece of 6061 alloy 1500mm square cheap.

    I will post pics of progress for interest.

    Its quite substantial? And that goes back to my lack of design on screen to what actually gets made? Yep.

    So after all this I look at the mounting of the 4.5kw spindle I have. And I reckon its not very good. The box that the spindle came in, has 6 M8 mounting holes. Spaced 36mm apart. I am hoping someone will say, no, thats fine. It wont vibrate in its housing. (attached)



  14. #14
    Member peteeng's Avatar
    Join Date
    Jul 2018
    Location
    dum dum
    Posts
    6248
    Downloads
    0
    Uploads
    0

    Default Re: Time to strengthen and upgrade....

    Hi Boyd - Attached? Peter



  15. #15
    Member
    Join Date
    Jun 2013
    Posts
    443
    Downloads
    0
    Uploads
    0

    Default Re: Time to strengthen and upgrade....

    Attachment must have fallen off. Attached is an exploded view of the machine I have 95% built out of 20mm alloy. The main rear is glued and bolted to 39.6mm thick. Large.

    The spindle though is bolted through quite close together bolt holes in the alloy extrusion it arrived in out of factory. I guess I see it as wobbly inside its box. I may well be wrong, hope I am. But now it looks flimsy and small against my new built axis. The spindle plate I am going to machine out of 31.75mm 6061 plate. The one expensive piece of alloy I need to purchase.

    I will post pics of progress later today

    Attached Thumbnails Attached Thumbnails Time to strengthen and upgrade....-4-5kw-spindle-jpg  
    Attached Files Attached Files


  16. #16
    Member
    Join Date
    Jun 2013
    Posts
    443
    Downloads
    0
    Uploads
    0

    Default Re: Time to strengthen and upgrade....

    Time to end this thread. Many thanks for the advice. I used it and put something together that I ran for the first time last night. For me, it was all about making the machine rigid enough to take out a resonance that went through the whole frame. I worked out what it was in the end and the gantry, whilst heavy and large, managed to resonate at a certain time.

    The whole Z and X axis was built on the bench out of a 1500*1500*20mm sheet of 6061 I purchased for cheap. I think it was approx 180hrs from design in CAD to machining to assembly. Very cool only one component went wrong and it was one from an old file I machined out. The Z assembly I have bolted through. What I mean, is everything is connected. The bolts for the Z rails, go all the way through to the ribs on the rear. I have 130mm m8 bolts running through the sides into the linear blocks for the X. Zero welding, the main back panel for the Z is made up of 2 x 20mm plate. Fixed together with a huge amount of SS bolts and also glued. Its the aircraft engineer in me - I like lots of bolts in a line lol

    I was unsure if I would have trouble but the Z is actually running on 4 rails 6 blocks. 2 rails are on the spindle plate.

    So last night my test was a 2mm climb cut, DOC 20mm with a 10mm endmill and wow did it go well. Absolutely stoked to get this performance I have been chasing for a very long time. A couple of months ago this would have made a huge racket and I would have run for the E Stop ha.

    Anyways, it took me 15min to clean up the huge pile of chips.

    Posting a few pics. New aluminum looks so nice when its new. Dont look past the machine my workshop is a massive post assembly mess haha

    Ok. I want to design and integrate an ATC. I have done a LOT of reading. I have a cheap chinese BOB. Unfortunately I am going to have to start one of those "where do I start" threads. Hate that part as I am in the line of those. Just have not found the info I need yet......

    Attached Thumbnails Attached Thumbnails Time to strengthen and upgrade....-20221022_104202-jpg   Time to strengthen and upgrade....-20221022_104051-jpg   Time to strengthen and upgrade....-20221022_104026-jpg   Time to strengthen and upgrade....-20221022_104109-jpg  

    Time to strengthen and upgrade....-20221022_104036-jpg   Time to strengthen and upgrade....-20221022_104248-jpg  


  17. #17
    Member peteeng's Avatar
    Join Date
    Jul 2018
    Location
    dum dum
    Posts
    6248
    Downloads
    0
    Uploads
    0

    Default Re: Time to strengthen and upgrade....

    Hi Boyd -Well done. I thought aircraft bolts were always staggered? Your fastener supplier is on holidays in Hawaii Peter

    afterthought - did you use shielded cable on your inverter to spindle run?



  18. #18
    Member mactec54's Avatar
    Join Date
    Jan 2005
    Location
    USA
    Posts
    15362
    Downloads
    0
    Uploads
    0

    Default Re: Time to strengthen and upgrade....

    Quote Originally Posted by boydage View Post
    Time to end this thread. Many thanks for the advice. I used it and put something together that I ran for the first time last night. For me, it was all about making the machine rigid enough to take out a resonance that went through the whole frame. I worked out what it was in the end and the gantry, whilst heavy and large, managed to resonate at a certain time.

    The whole Z and X axis was built on the bench out of a 1500*1500*20mm sheet of 6061 I purchased for cheap. I think it was approx 180hrs from design in CAD to machining to assembly. Very cool only one component went wrong and it was one from an old file I machined out. The Z assembly I have bolted through. What I mean, is everything is connected. The bolts for the Z rails, go all the way through to the ribs on the rear. I have 130mm m8 bolts running through the sides into the linear blocks for the X. Zero welding, the main back panel for the Z is made up of 2 x 20mm plate. Fixed together with a huge amount of SS bolts and also glued. Its the aircraft engineer in me - I like lots of bolts in a line lol

    I was unsure if I would have trouble but the Z is actually running on 4 rails 6 blocks. 2 rails are on the spindle plate.

    So last night my test was a 2mm climb cut, DOC 20mm with a 10mm endmill and wow did it go well. Absolutely stoked to get this performance I have been chasing for a very long time. A couple of months ago this would have made a huge racket and I would have run for the E Stop ha.

    Anyways, it took me 15min to clean up the huge pile of chips.

    Posting a few pics. New aluminum looks so nice when its new. Dont look past the machine my workshop is a massive post assembly mess haha

    Ok. I want to design and integrate an ATC. I have done a LOT of reading. I have a cheap chinese BOB. Unfortunately I am going to have to start one of those "where do I start" threads. Hate that part as I am in the line of those. Just have not found the info I need yet......
    Good job I knew you would get it right in the end, the Table looks good too and is a big part of the success, the ATC there is not much you can do as yours is an individual machine built by you

    You can start by making a rack where you want to pick up the Tools, you can make plastic fingers to hold the tools the rack sometimes needs to have some up down movement so mounted on guide pins, this can be linear Bearing or linear rails for the mounting, that are spring loaded this helps when there is a little over travel, when picking up a Tool, the rest is writing a programing, this one looks ok and is using a carousel, https://www.cnczone.com/forums/auto-...cnc-posts.html

    Mactec54


  19. #19
    Member
    Join Date
    Jun 2013
    Posts
    443
    Downloads
    0
    Uploads
    0

    Default Re: Time to strengthen and upgrade....

    Ha - about NZ$400 on stainless fasteners. I do have a lot left. They are a bit soft to use but do make the difference. I was an engine tech in place of the airframe guys - I do remember with the fasteners there were rules like edge distance but thats about it though. They do look cool though huh.

    The spindle conductors are encased in a stainless braid all the way from the VFD. Ive been working in the medical electrical industry for a while now where all earths need to be a super low resistance throughout the installation. The machine is seriously well earthed and connectedd directly to a live earth about 11m from the machine. Personally I am very cautious with 3 phase its such a huge leap from the domestic line voltage - aye, like lose a finger kind of stuff. I am looking at a G Penny 6kw ATC spindle. The one on the machine is a G Penny 4.5kw (non ATC) and has run fantastically. Yep - going to get one.

    Thanks for the words and link Craig I will probably have to get in touch to set this new spindle up when I purchase it.



Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  


About CNCzone.com

    We are the largest and most active discussion forum for manufacturing industry. The site is 100% free to join and use, so join today!

Follow us on


Our Brands

Time to strengthen and upgrade....

Time to strengthen and upgrade....