Have you thought how you will bolt the Z rail blocks and the Y rail blocks on as they appear to clash with each other. It might be better to make the Z back plate wider. ..Clive
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Have you thought how you will bolt the Z rail blocks and the Y rail blocks on as they appear to clash with each other. It might be better to make the Z back plate wider. ..Clive
Thanks, they are kind of close but the bolt holes don't line up so I was thinking they would bolt onto tapped holes in the plate with hex head screws from their own respective sides but as I've never fitted them before it's just a plan until I get the hardware in front of me. Widening the plate would be a useful option.
I missed this which is unusual for me has it happens often so I'm always watching for it but you didn't have it like that before so didn't pay any attention this time.!! . . . . . Clives correct thou you can't do it you'll need to lower/lift or widen. . . Chicken and Egg problem.???
Regards 90Deg problem then yes needs same attention but milling ends of 80mm box section will need big mill with large tooling. Having plates for gantry sides which bolt to base plate and are held 90deg with bracing brackets is much easier to do.
Welding will be good but will still possibly try to twist when released from Jig. Even then you can't be 100% sure faces of both box sections are exactly on same plane and that's why I'd use epoxy in this situation.
The reason I used box section for gantry sides was due to large strength advantage over plates.
I thought this might be an idea for attachment of sides to aluminium.
Attachment 10139
By welding a plate (with nuts welded to the back of it) about 6mm in from the end of the box section, I could easily file the box profile edges to 90deg. I suppose you could then fill the 6mm deep cavity with epoxy if need be. Maybe use 1/2" plate and drill & tap 4 holes instead of welding nuts behind a thinner plate.
Epoxy plan for gantry horizontal members will be fine.
Attachment 10151
1. Ball screw bearings moved to outside of frame or as suggested I might use BK/BF instead.
2. Support brackets for sides increased in size
3. I think you are saying that to fit the bearing blocks I need to drill through the ally backplate and use nuts & bolts rather than tapping the backplate and screwing in from each side with set studs ?
Metal ordered, ball screws etc. ordered (Chai), pondering HIWIN or similar guides but Zapp is easiest to order these from and they have exact lengths I need without having to cut them. Also I (re)decided that I didn't really want a challenge building this machine, I just want it to work as planned so I can use it. With this in mind then I reverted back to the L gantry which I earlier said I didn't like :ambivalence: but it simplifies the making of it quite a bit. It will be something like Matt's (kingcreaky) machine with a few changes.
Since it seems you're happy to get the rest of the linear motion parts from China, I'm surprised at your choice of supplier for the linear guides. There are quite a few sellers on aliexpress which sell them for a lot less. For example:
BST AUTOMATION - Small Orders Online Store, Hot Selling Ball screws,ballscrew,linear guide and more on Aliexpress.com
Just send them a message with the lengths you want, and make sure you get the right preload - i.e. not zero.
I didn't ask Chai about the rails because on ebay he seemed to be selling only round rail. I looked at Aliexpress and that's why I'm pondering, sometimes I just like it easy rather than cheapest.
Ball screws etc. arrived from Chai all machined exactly to my spec. with dimension F extended to 30mm for pulley.
Decided to get Hiwin rails and blocks from UK but not from supplier I was thinking about, arrived within 2 days, great !
This weekend got the Ethernet Smooth Stepper, BOB (DIYCNC), Spindle board (DIYCNC), 5v and 24vpower supplies.
Lashed them together and plugged into PC, it took a while to get it sorted as this is the first time I've used Mach3 and the hardware but by afternoon had everything working and the inputs set up as per my drawings. Need to get the control cabinet layout finished so I can order the right size box. Having to wait for the AM882's coming in.
Also got the main power supply transformer, 22000uF capacitor, bridge rectifier, aluminium plate to mount it.
Nearly got the bottom frame design finished and have all the metal ready to start cutting, Brother-in-law booked in with his MIG.
I've just been reading about roof truss design and used the info to finish my frame.
All box section is 50x50x3 steel except that in blue which is 100x50x3.
Red plates are 10mm steel
Yellow gussets are 6mm steel
Any thoughts ? and keep in mind the fairly small overall dimensions.
Attachment 10465Attachment 10466