Mikey_d, that is of course, possible. It would be good for repetitive work, if I knew the size of the workpiece beforehand, and if it was square. For instance when engraving on a sheet of 4x2 engravers brass or something. What I was trying to explain was the fact I may be machining "some old piece of scrap" which I have no intentions of cutting to size first, or making it square, since the router can do all of that for me. And again, if I have a set z height, I will need to make sure that when I change tools, that that height remains the same. Handy if I was always using fixed tooling, but a pain when I just need to swap over a router bit from the collet. Yay, eddie_dane, glad you like it! On with the update! I been busy at the lathe the last couple of days, oh yeah, that was after trashing my old CNC router, making some space in the shed, and finally getting the new one in there! I am putting off finnishing that z-axis that I began so long ago, as it will be the most difficult part to get right. In the meantime, I've been knocking up some bearing blocks: These will hold the bearings, which in turn, hold the leadscrews. Here it is assembled with two bearings inside: I have made a 40mm hole at each end of the table for these units to go in, and they are a nice tight fit. I will need to get them bolted in place, but first I need to turn down the leadscrew ends to fit snuggly inside those bearings. Problem - how do I turn the ends of 1500mm leadscrew, on a 12" lathe? Simple really! Now that was damn dangerous, so please, don't try this at home kids! Here's a close up You can see a shoulder on the right, this fits inside the bearings, then the rest of the shaft is turned down slightly narrower. This section will be tapped for a nut, then thinned down some more to hold the drive pulley. I've not got that far yet, but should get it in place tomorrow! Thanls for reading all this garbage!
I might be stubborn, but I still don't see how setting a fixed zeropoint could prevent you from doing things the way you described and still get advantages of fixed zeropoint... What height are you talking about ? Height of a tool ? As before, any decent control software (I recall you plan to use Mach2 ?) should have option for dynamic tool lenght correction.
Oh arse! I've edited this post twice now, lets just say that when you build your own CNC, you get to choose whatever system yo like/are used to! Edit 3! If I am using the fixed tooling, then fixed z is fine. If I am using a router collet, which I will be quite often, then fixed z is out, as it is quicker to jog z down the workpiece top and set 0. Control software is Linux EMC, I have not mentioned Mach2
Kong, your skills never cease to amaze me. However most of the stuff your going on about seems to fly right past me, probably make more sense once it all comes together!
OOh it's looking ugly!! Yep, ugly, but quite amazing. I got that Z-axis partly installed today, having spent the last couple of days fighting some dirty stomache bug which left me with little strength. I just had to get out there today and get something done! I did a lot of drilling and tapping, but the work that is done is as square as I can get it without the router being in place to hold the dial indicator. Please excuse the mess, it's raining right now, so no room to spread the tools around outside! Believe it or not, that is as far back as I can stand to take a photo without tripping over a big pile of crap in the corner!
Awesome! How easy does it slide on the x and y axis? And you're completely forgiven for the mess. I can't touch any project without having things stack up like that. Your leadscrew turning solution is brilliant, albiet a little hazardous looking
Ouch, the pr-pr-pr-price! I've probably dropped around £1500 on it so far, but that does include a mitre saw and the Taig lathe. My credit card has been hit real bad! On a side-note, I have been thinking about your fixed axes. I am beginning to like the idea of having the fixed rail along the x-axis to rest the work against, with a fixed x=0. However, I still believe the variable system is better, but probably because it can be used as either fixed or variable. Nice point though, you really got me thinking! Marcello, it is fractionally sticky at the moment, I need to shim the top cross bearing rail by 0.5mm to stop it. I just haven't got around to that yet. Could you please elaborate on the "hazard" you mentioned - your input is greatly appreciated! edit - ok, just re-read your post, the turning on the lathe, lol!
Not as pricey as I thought it would have been. But if I recall it right you haven't still got servos and spindle, which will definetly lump up the sum a bit. Using fixed zero points shouldn't prohibit you from using variable zero point. In professional machines this is achived via zero point move. Seeing you try to make some money with your machine I belive that fastest and easiest setup of workpiece should be quite important and that Why I in first case recommended confiquiren some fixed zeropoint. It even could be just some drilled holes in the table, so you can place your misc. shaped workpiece quickly at zero. What comes to height of tool, I just checked that it's possible in EMC to use variable tooling height. If you dont need much depth (Z) in your machinigs you could think about inserting tools into the spindle all the way to the bottom. And you would have to measure tool just once using caliber or maybe could implement and auto measuring using. Then you would have a tool library where you could pick the tools you need and just enter numbers (height of tool and diameter) from somekind of database
Cheers for the advice, I'm getting there! Yup, I got servos. On the first page, i have 4x 24v, 7.5Amp 350oz/in servos. Also have the gecko 320's to drive them. As for the spindle, I will be using a 1250w router for now, although I am seriously considering a 3HP Porter-cable from the US in the near future. No way I can afford a Perske!
I would like to build one of these but the price I came up with was a little over my budget. so I will have to wate. Looks cool man.
No problem, happy to help Ah, I was remembering something about servos but seems like I had some clitch in thought process So there shouldn't be any major costs other than better spindle coming up ? If that's the truht I could say that it will be quite cheap (which is ofcourse relative ;-) You could try looking used spindles from companies manufacturing professional CNC-machines, maybe a long shot
Don't forget though, almost all of it is second-hand. I thnk the only thing I have had to buy from new is the gecko 320's. Even those servo's are obselete stock I got from ebay. I hate to hazard a guess at the cost of doing one with all new parts, I know those linear rails and bearings I have would have cost over £2000!
Kong I got a sweet idea. Something you can market. Take some real thick plexi and CNC out the 'iPod 3G Dock' body. I can post you the parts (as I've taken mine apart) and then ..*voila* ClearDock Stick some leds into this baby and you got a nice retail item!
Mate, I'm having some real head-aches this week. I have been trying to make the brackets to join the z-axis linear bearings to the front plate. It seems everything I do goes wrong, and ends up in the bearings locking up on the axis. I have given up today, after four solid days of trying! Next idea is to buy some 2x2" square aluminium bar stock, cut into lengths, then bore out each on the lathe to hold the bearings. I have ordered the aluminium today, but I need a 4 jaw independant chuck for the lathe to hold the square stock, and the only place in UK that sells them is shut until Saturday!! With the increased accuracy of the lathe, I'm fairly sure they will turn out ok. In the mean time, I will be getting the x-y axis leadscrews in place, and hopefully the motors too. Thanks for the heads-up Oh yeah, and to top it all off, the starter motor on my car has died, so I must find time to sort that out too!
Never rains but it pours eh Kong? I feel your pain... You have some seriously nice work going on with this project and I have been following it in awe. I look forward to seeing it all up and humming. Take your time too and take a break if you need it. Well done so far mate
Wow, that's rough, man. Starters can really put a suck in someone's day. Especially if it's a front-driver. Ewww.. Wish I could just stop by and help you with the router. Do some brainstorming or something. Dumb ocean. ANYway, if there's anythin I can do for you, please ask. I've got the model in cad so maybe I can help diagnose something.
Great work Kong !!! That is soem great work i cant wait to see it when its done, and msot of all see some of the great things you make with it. Keep up the good work, and dont give up you've come so far.
