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First V-Carve Output Simulation, using 8mm Endmill, It looks so simple when you look at this picture.... Well its not.. This is just the backplate from the Y-side.
Attachment 7872
I Used the Sketchup model just for dimensions, and re-drew the lot in V-Carve, none of this fancy importing stuff, it never goes right for me..
Rick
Rick the trick is to import the 3D model then extract the edges, dump the model and the lines not required and use these for the toolpaths. . .:thumsup:. . . . Simplizzz
Edit: This happens all the time. Folks ask me to make stuff and send me 3D models taking ages over making them only for me to just explode them for the 2D lines/arcs.!! . . . . .If they just asked in first place could have saved them hours. . Lol
Jazz if you dont mind me asking, What cam software do you use to output to mach?Quote:
Originally Posted by JAZZCNC
Rick
I use BobCad Cam V24Quote:
Originally Posted by Ricardoco
And the front of the backplate.
Attachment 7873
Just the mounts and the motor/Screw mount now.
Rick
Ok took a few pictures of the progress.
Attachment 8267Attachment 8263Attachment 8264Attachment 8265Attachment 8266Attachment 8268Attachment 8269
Now comes the fitting of the motor assembly and X Twin Ballscrews...Hmmm Im sure that will be fun, it took me long enough to get the frame parallel..
Rick
Ive now reduced the Z to 250mm Max and reduced the gantry mass considerably. Im hoping to have the screws/ motors mounted and close to test by tomorrow evening, But i cannot do any tests antil i recieve the two pulleys and belt to connect the steppers together as a precaution against single motor failure twisting the gantry. Im also looking for a source of 1.6mm 8x4 sheet steel, but the delivery costs are more money than the steel itself... Grrrrr
Rick
Rick If those pieces that look like 1" box are for the bed support then it's not going to strong enough with big chance you'll get bed dipping.
The forces when plunging and ramping etc can be high.! Even my 50mm box with 16mm Ali bed can flex when plunging into hard materials. Honestly don't under estimate the forces.!!
Hi Jazz, that 1" box is going to be supporting the water bed for the plasma only. The milling bed is going to be much tougher and stiffer. There is a 50x50x3mm box section frame topped by 40x40 profile for the Router/Mill bed that is still in production, you should see that appear about mid march.Quote:
Originally Posted by JAZZCNC
Rick
Ok Just building the secondary steel frame that goes inside the main frame for milling/routing, Obviosly im not going to be putting a 7'x4' ali bed on it, the most of it will be a sacrificial bed for routing. So i was wondering what size ali plate to embed in the frame for machining ali. So the question would be. What are the largest size projects you have done and what would be the minimum size ali bed you would choose given the choice, not forgetting quality over quantity and of course price.
I would like as many opinions on this as i can get please.
Rick
If at this stage you can't afford or justify getting a piece of aluminium big enough to cover the whole bed, or strips to cover the bed leaving slots, then I'd say the minimum is a piece wide enough to span the machine and long enough to be useful. That means about 4' by something, maybe 1200x600 would be enough to cover most things. The biggest single aluminium part I've machined on my router was 1015x700x25.4mm and the biggest aluminium 'job' so far has been 1480x715x20mm, which probably doesn't help much with your question as it depends entirely on what you're planning on making. Also these parts were machined when I still had an MDF bed, so if the part wont fit on you're aluminium bed it's not the end of the world. Since your bed will be well supported I see no reason to get more than 20mm thick aluminium.
Ideally i would like to cover the whole bed in profile, but the cost i suspect would be well over the top, in fact i dare not look although it wont be as much as it was when the bed was 7' but since i rebuilt the bed length at 6'6"x4'. I would love a complete bed ali with t slots but im not sure i can justify the massive percentage of the final cost.....Quote:
Originally Posted by Jonathan
So your largest Ali machined part was 1480 x 715. Cheers Jonathan.
Ok any more offerings??
Rick
Agree 1200x600 would be my minimum if planning on cutting thicker Aluminium has most Single parts will usually fit in that space and only if your nesting several parts will you need much above this. Even thou my 1200x1200 bed is all Ali (slots) usually half of it has piece of MDF or HDPE spoil board on it.
If your cutting thin Ali plate like 3-4mm then you'll probably want more space and be cutting large single pieces anyway. So then again you'll probably find an MDF spoil board will be used for holding and bed saving reasons.!
Part holding is a challenge and can be pain also it can be very part dependent.? You'll find even with an Ali bed you'll use some form of protective material or spoil board between part and bed.!
Hi Jazz did you make your slots, if so how or did you buy the plate somwhere if so where. I must admit your 1200x1200 seems like a nice size to me as im unlikely to be machining anything larger... Mind you never say never... If i were to go for a solid plate that size at 20mm thick i would be looking for someone else to drill and tap all the holes as I wouldnt look forward to that..Quote:
Originally Posted by JAZZCNC
Rick
He used aluminium flat bar, so the strips span the width of the bed with a small gap (12mm ish?) between each strip so you can put a bolt through and use nuts/T-nuts or whatever underneath the bed. Can also skim the strips several times without problems. I went for a single sheet to better contain flood coolant and I'm going to add strips on top to make T-slots.Quote:
Originally Posted by Ricardoco
50p per hole ;)?Quote:
Originally Posted by Ricardoco
Drilling them is easy if you use the router with a carbide drill - it's tapping that's the tedious bit.
@ Jazz..(or Jonathan if you Know) Flat bar say 2" wide ontop of what and fixed how??Quote:
Originally Posted by Jonathan
I suspect when doing the holes i will get one of those tapping attachments if i go for the single plate.
I can streach to a plate 2000 x 1220 x 10mm at a push for under £600 but will that do the job....
Rick
Jazz has said previously on this forum:Quote:
Originally Posted by Ricardoco
But I recall him advising that greater than 16mm thick would have been better, simply for the extra strength and I guess you can surface it more times.Quote:
bed made from 40x16 strips spaced 10mm apart to create Tslots.
Like Jon says used 1.5" x 5/8" (38x16mm) Ali strips with 10mm gaps giving 45mm centres between slots. The slots where cleaned up with 10mm cutter taking the difference away leaving 45mm centres and ensuring parallelism to Axis. (See pics)Quote:
Originally Posted by Ricardoco
Regards drilling and counter bores etc then I clamped the strips in place and the machine drilled and counter bored them in situ. I just tapped the Holes with spiral tap in Hand drill.
My bed frame is 50mm box with braces every 16" which the strips fasten too. The gap between top and bottom of box means no machining or tapping and the T nuts just clamp to under side of strips.
If coolant is need then it's easy enough to make it sealed tray by fastening Ali or galv sheet on underside.
I looked at all ways and at the time this was the cheapest way I could found.
Personally I wouldn't use 10mm has I can flex 16mm at times when clamping hard.
Yes thats correct but more for Strength than surfacing, I've only had to surface mine 1 time and that was only 0.3mm ish.?Quote:
Originally Posted by Jonathan
Ok a little more progress today.
Attachment 8385Attachment 8386Attachment 8387Attachment 8388Attachment 8389Attachment 8390
Now that all the alignment has been completed the Left and Right gantry supports have now been seperated.
Rick
Welding looks good, but the garage looks nearly full!!! G.
Thanks G, Luckily its a three car garage and thats, just 1 third, there is an in progress 1932 V8 HotRod taking another third, and a Half spray booth taking up half the other third but luckily they are 21' deep so there is more space than first appears..Quote:
Originally Posted by GEOFFREY
Rick
Sounds like an interesting garage set-up. What is the hot-rod? Even with your garage looking so full it is 20x tidier than mine. G.
It could always do with being bigger and tidier..LOL, Its a 1932 Ford 5 Window on a 1940 Chassis, or will be, it should look a little like this..Attachment 8391Quote:
Originally Posted by GEOFFREY
..
Rick
WOW! Seeyou on Sunday. G.
Sweet ride, reminds me of a TV show I used to watch, American Hotrod based on Boyd Coddingtons custom shop.
It will be when its done, Complete Chassis re profiling, Lowered to 6", body over Chassis, 31" cross ply rears (the thin ones) Hemi motor, 6 carbs....and all without Boyd funding levels..Quote:
Originally Posted by Iwant1
Rick
Ok today I hooked up Mach3 to the X Axis, Arrived at 200 steps Per/400mmMin/100Acceleration in motor tuning, Now here is where the brain goes mushy and i know ive asked this question before, The Gantry travels 2000mm in 18 seconds, the ballscrew is 10mm pitch, how do the settings in mach3 and the actual speed of the gantry relate to each other..
Rick
Ok i think i have it.. LOLQuote:
Originally Posted by Ricardoco
200 Steps per Rev x 8 microsteps = 1600 / 10mm pitch screw = 1600/10 = 160 steps per unit. not the 200 i put in, not sure what that will do when i put it in tomorrow when i get in but i will let you know.
I knew ide asked before lol
http://www.mycncuk.com/forums/machin...-mach-3-a.html
Rick
I was still trying to work out what the question was!
Ok finaly Purchased the Rails for the Y Axis.
Attachment 8469 Attachment 8470
Ive got 2x GL20TF + Rails at 1300mm, (when they arrive that is)
Rick
Hi Rick,
can I ask where you got the from?
Regards,
Tom
You May.. I got them from Korea..Quote:
Originally Posted by dsc
Rick
Ok today i put the Y to X registers in and fitted the bed to the registers, thats really all i can do untill the Y rails turn up and then I have the Z machined and fit it, so ive done one of those boring videos just to show the X axis moving on the twin rotating ballnuts and 2510 ballscrews, it is set on the conservative side at the moment and i may just leave it there, X100 input in to mach moves the gantry 1m so thats correct now..
http://www.youtube.com/watch?v=u3B74HazzZk
Now that made you excited didnt it?? cmon admit it. ok it didnt me either..
By the way the irritating noise heard when the gantry changes direction is the Clamps holding the gantry on.
Rick
Bonus points for filming the nuts spinning in the next video...Quote:
Originally Posted by Ricardoco
Mach3 should be used in milimeters, not centimeters, so going from X0 to X100 (or just moving 100 from the current position) should move 0.1m, not 1m.Quote:
Originally Posted by Ricardoco
Ok I will upload the one with rotating Ballnuts when i get the A/V sync sorted, and how would you correct the measurement issues.Quote:
Originally Posted by Jonathan
Rick
Ok not a great movie i know and the audio was rubbish so i had to substitute itQuote:
Originally Posted by Jonathan
http://www.youtube.com/watch?v=1XlA7qdp63w
Ok let me see, its showing 100 on the DRO when it is moving 1000 so that is a 10th so steps per in motor tuning should read 200 x 10 = 2000 and then X100 should move the gantry 100mm yes?Quote:
Originally Posted by Jonathan
Rick
Vids not boring, pics look good. G.
Hard to tell from a video, but it looks to be running smoothly without whipping, which is good.
If the step/mm value before, which caused it to move 100cm when commanded 100mm was accurate, then you just need to multiply it by 10.Quote:
Originally Posted by Ricardoco
There's a bit more to it though. You need to make sure that you don't hit the kernel frequency limit in Mach3. It's best if you can to use the lowest frequency, which is 25kHz. This means the port will output a maximum of 25000 pulses per second, so if you divide that by the step/mm value you get the software limited maximum feedrate. For example if it's set to 2000 step/mm, then that's 25000/2000=12.5mm/s or 750mm/min. If that feed-rate is too low, then you either need to reduce the microstepping resolution (e.g quater stepping instead of 1/8th) or raise the kernel frequency.
Ok i went to the workshop and in motor tuning ive set steps per to 20- Velocity to 3000 accl to 200, Oh im using metric, now when you type in X1000 the gantry travels 1M so that much is correct but im not sure it is the only way to do it the drivers are on the lowest setting which is 200 per rev. with four people sitting on the gantry it dosnt evn know you are there..Quote:
Originally Posted by Jonathan
Rick