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I have book marked it and I will give it a try next time I set a pair of pulleys.Quote:
Originally Posted by Boyan Silyavski
It took me a while before I could bring myself to mount pulleys with absolutely no possibility of adjustment, but now I can't imagine why :lemo:
Quick question gentlemen, on my long axis I have a motor ballscrew setup for each side, what is the best way to align & make parallel both rail blocks/side plates/etc before attaching the gantry pieces and make one of the motors a slave? should I get a long machinist square? I don't have one that would reach all the way to the other side atm but would that suffice anyway?
thanks!
I bought a straight edge and set one rail straight. Then put the carriage block on the beatings and set it square with a dti mounted on the straight rail. Then set the carriage plate square on the other rails carriages. Then put my gantry bottom plate on setting it square with both carriage plates by putting the end plates on as they fastened to both the carriage plate and gantry bottom plate ends, checked with engineers squares. Then drilled and loosely fastened the other rail at one end and sliding the gantry down the rail I marked, drilled and tapped as I went down so using the gantry to align the rails....
Another question gentlmen, when I mount my motors, how do I determine the best tension on the belts? both my gantry and Z will be belt driven and I have already used a calculator site to determine the belt length ( and bought it ) based on the distance between the points. but then what actual distance would I screw the motor at?
thanks!
Update:
had issue with my Z motor turned out the cable had some issue so I just cut one side and directly connected it to the driver instead of the 4-pin plugs setup, works fine now.
assembled everything and tested and so far satisfied, still I got a long way to get it right:
things need to be done:
-Spindle speed control via mach3 : had issue before of speed being off, probably needed adjustment of the voltage or something.
-limit switches : using software limit only at the moment
-checking alignment/parallel via DTI : to be honest I have no training on using this properly and feel like my machine doesn't have room to adjust correctly, however I can live with a little bit of error for now, as long as the thing works!
-making triangular support legs with leveling: something I missed was to make the frame have adjustable height on each corner, now am thinking of just mounting extra 4 pieces on each corner of the frame and have those lift the whole thing up and balance accordingly
-Drag chain attached to frame : again my stupid and impulsive attitude prevented me from designing a side where drag chain can sit so I have to think about manually drilling and just attaching a flat panel so it can sit on it, no big deal I guess for now.
-Double check tension of belts : again no formal training so no idea how to do it properly but by feel I think I got it decent tension :hysterical:
-Connect water cooling to spindle
-Cable management of Z axis
-Actually cut something : will probably try wood(MDF) first, then maybe try my luck with other material and ultimately aluminium, anyone wanna recommend speeds and feeds for me?
-and many more I'm sure, hope I get some positive feedback from you guys in order to make it better!
A quick photo of the machine:
http://www.mycncuk.com/attachment.ph...id=15949&stc=1
Video of axis movement , before mounting spindle( at time of this post it is still uploading but give me 20mins or so plz hehe)
https://www.youtube.com/watch?v=sIeMDkg2KVI
am sure u guys might have some comments, particularly on sound of long axis movement, had lots of issues with it being flexing/bending if I tighten the gantry too much or so, the ballscrew ends might need shimming but not sure how to approach it yet.
Your gantry motor belt is looking extremely loose on video.
Just google or youtube - timing belt tension - and you will be expert belt tension operator.
thank you already fixed it but I will have to learn the right procedure as you mentioned.
I tighten belts by making sure I can just about twist (by hand) the bit of belt run furthest from any pulley by about 90 degrees. I know this is also subjective but it should get you somewhere close
Hey again, yesterday I was finally able to test cutting aluminum after getting the t-slot table and fixing it in the frame. I need as much guidance and advise as you could provide me since I had several issues.
I was spraying the bit with WD40 as well as having the mist coolant system spraying water and air ( but the water/oil valve was off so only air ) and I did that to get the chips to clear since I was milling a hole, however it was far from ideal and although had chips flying in direction of air still had plenty not moving out of the hole, I did a slight adjustment to direction and angle of nozzle and helped a bit but I didn't want to just keep doing that.
second issue was that the chips that flu were flying onto my long axis rail and a bit on the ballscrew which was behind it, wasnt an issue now but it will definetly be one, I held on purchasing dust covers because the supplier i found asked for a high price, appreciate if anyone can point me to low cost solution on this part
third issue is that the piece was a bit hot to touch, so I guess I failed of having the heat transferred to chips instead of the part/stock, appreciate if anyone can guide me on proper oil/water/air combo for lubricating and cooling during milling aluminium.
spindle was around 7500RPM feed rate 150mm/sec (taking it real slow to be cautious) however I read somewhere that aluminium needs a bit higher feed rate so to not stick, but not sure about that, your help here is again appreciated.
cutting tool was 4flute 8mm HSS, test was milling a circle with 23mm radius and 20mm depth, my stock was just a scrap and it needed facing on all sides like no body's business, but this was just a test and wasn't worried about it being a bit tilted and not reach all the way through ( you can figure by the photo and the small cylinder piece left at the center)
I still am not sure how parallel my spindle is to my table and how much error is there when I move it length/side wise but it seems decent enough for now as I'm way below the level of making precise parts. will definitely be asking for tips on this as well but I also know that due to quality of parts and my labor it wont go beyond a certain level of accuracy and precision.
here are some photos, am sure you will laugh when looking at the back side photo but I will try to make it tidier hehe, also am a bit sad about having to put the vise horizontally as opposed to the standard way but thats because I opted for bigger/lengthier t-slot table for mounting large wood stock as opposed to having a a smaller t-slot table but horizontal slots instead of vertical. it is bothering to turn the vise but it's a small issue no big deal.
Attachment 16269Attachment 16270Attachment 16271Attachment 16272
It looks like you have done a profile cut to make the hole A pocket would have been better to have the hole cleared.
You don't say how many flutes the cutter has etc.