AndyUK's Build - 1.2x1.0m Gantry

[AndyUK]

Thanks Dean - I used Aspire's default step over, so no idea what it was set to! I'll look into it tonight and get it into that range.

Out of interest, what would you expect to see DOC wise on a router like this with a 4mm single flute? APT suggests slowing down from those parameters once you're over 1.5 D, but I assume that advice is really for mills; 6mm felt like quite a big chunk to be taking.

[JAZZCNC]

Thanks Dean - I used Aspire's default step over, so no idea what it was set to! I'll look into it tonight and get it into that range.

Out of interest, what would you expect to see DOC wise on a router like this with a 4mm single flute? APT suggests slowing down from those parameters once you're over 1.5 D, but I assume that advice is really for mills; 6mm felt like quite a big chunk to be taking.

Ye aspire is mostly based on wood which is a little less forgiving so any small scollops can be sanded away but in Ali you want a smaller stepover for the best finish.

Difficult to say because every machine is different, spindle power and rigidity plays a big part. If it was me I'd start at 50% D and feel your way down. Or just go for it turn the spindle up to full RPM so you are getting Max torque then go with 1.5xD and play with feeds n speeds.

[AndyUK]

If the 4th axis is for marking round parts like a rolling pin etc. I have done it on my laser engraver by using a small stepper and connect it to the Y axis, intead of the gantry moving the length it stays still but the rolling pin turns as the laser writes, not sure which axis is which on a cnc router so it might be X in your case. Its a simple device with a 3d printed mandril one end that grips and a pinpoint on the other and the work is held in between, I'd upload a photo but i gave it to a friend. Its not a full permanent 4th axis but you can write on round tubular objects, on a router probably cut them too. Not sure if its what you need, just a thought.

Derek
PD Are you the same Andyuk that designed the belt tensioner for the eleksmaker A3 pro laser engraver, every time I see a post of yours it reminds me of it as the way you write AndyUK is the same.

Hi Derek,

Sorry, not the same, just another Andy from the UK ;)

Yes I've seen that type of 4th axis, quite ingenious! I worry about the accuracy of such a system though, and I wonder if the Cam is a nightmare! I was more thinking along the lines of a high torque stepper, some gear reduction, a chuck and a tailstock.

Thanks for that Jazz - much appreciated.

[Muzzer]

Not sure if it's quite what you are after but I've just about finished a fairly conventional 4th axis using one of the harmonic drives and a servo motor, all culled from one of the Korean scrapyards. Looks good so far - had it jogging yesterday.

This is for a metalworking milling machine, so has a 125mm 3 jaw chuck which I have bored through 36mm, so I can hold long stock.

[AndyUK]

I like! Thanks Muzzer :)

[AndyUK]

Quick update to the Aluminium Bead Presses. Other half demanded six sizes of the 3D hearts in both a horizontal and vertical press. Settled on a 0.2mm step-over - we did some tests lower down but whilst the finish was buttery smooth the tooling marks arn't translating into the glass, so decided this was a good compromise (or if they are, they're soon rounded up by heat). Getting some great consistency out of the presses, so happy customer :)



We're now exploring other shapes.... (The ribs are intentional - not poor machining!)



The machine is doing fantastically. Its been running 9 months now and hasn't skipped a beat. I had my first acrylic cutting experience recently which went very well. We used two layers to create an illuminated panel, solid grey on top cutting down through to a transparent opal - and if it wasn't a sign for my own address I'd be sharing pictures!

My 4th Axis dreams are on hold for the time being however - a Warco metalworking lathe has just arrived in the garage, which changes things slightly, and I now need to learn how to turn. Never a quiet moment!

[fer662]

This build is looking great! I've been following for a while since I want to rebuild my table to be pretty darn close to this one, only 1.5x1. I like the fact that you used an hybrid solution for assembling the table. My workshop is in the first floor so if i had to ever move and it was all soldered it'd be a death sentence. Is there any chance you would upload the solidwords stuff? Thanks a lot!

[AndyUK]

This build is looking great! I've been following for a while since I want to rebuild my table to be pretty darn close to this one, only 1.5x1. I like the fact that you used an hybrid solution for assembling the table. My workshop is in the first floor so if i had to ever move and it was all soldered it'd be a death sentence. Is there any chance you would upload the solidwords stuff? Thanks a lot!

Hi fer662,

Thanks :) Although my table is welded, and won't be coming apart without a grinder! The bolts were used to position everything for my first time welding, and are mostly aesthetic now. If I did need to separate the frame I'd need to repeat the epoxy levelling - its something I've mulled over, as we're considering building an extension which might trap the CNC in the workshop for good...

Happy to send over any pictures of the model you'd fancy and provide dimensions, but the CAD is such a sprawling mess its a nightmare to get everything together to share. I'm also not sure of the benefits - if you're serious about building, designing the CAD model yourself is very helpful in organizing your thoughts, and helps your understanding how it all fits together, and it needs to be specific to your components. There are also a number of improvements I'd make now I've gone through the process, so if you start a build log you'll get a lot of suggestions from all directions.

[fer662]

Hi fer662,

Thanks :) Although my table is welded, and won't be coming apart without a grinder! The bolts were used to position everything for my first time welding, and are mostly aesthetic now. If I did need to separate the frame I'd need to repeat the epoxy levelling - its something I've mulled over, as we're considering building an extension which might trap the CNC in the workshop for good...

Happy to send over any pictures of the model you'd fancy and provide dimensions, but the CAD is such a sprawling mess its a nightmare to get everything together to share. I'm also not sure of the benefits - if you're serious about building, designing the CAD model yourself is very helpful in organizing your thoughts, and helps your understanding how it all fits together, and it needs to be specific to your components. There are also a number of improvements I'd make now I've gone through the process, so if you start a build log you'll get a lot of suggestions from all directions.

Oh, for sure I would be making my own CAD, but since your design is pretty similar to what i had in mind i'm bound to stumble upon the same problems and decisions and thought having a tried and tested design would help me resolve those at some point. The most significant difference is I don't have access to a mill... I do have my current tabletop CNC that i intend to use to machine the aluminum flatbar into whatever plates I need, and I also have a hobby lathe (not the crappiest kind, I think its the same as the Warco you might be more familiar with in the UK).

Oh, so you essentially welded the sides, then assembled the table with screws and taps, and then welded it together? was it mostly to prevent it from moving?
What about the legs, did you solder anything below the open 80x80 tubes? I cannot bolt the table down to the floor because i have floor hitting and i'm sure i'll be unlucky enough to hit a hose with the drill. Probably won't be necessary as the table will weight a shit ton.

Sorry my reply is a mess! Yes, i'd appreciate any pictures you could send about how all the frame is attached.

Attaching a pic of my baby. I started this years when I didn't even have a workshop, let alone a proper one. It literally spent some time in the coffee table in the living room until i stole the laundry room from the wife. Now that i do and i've had time to see the flaws it's time for an upgrade. I already have all the hiwin style rails and longer screws. I'll be reusing only the longest axis rails that are now in X for the Y gantry (1m). I've already redone the control box and electronics and added the extra driver for dual X screws.

[AndyUK]

Ok sounds good - let me see what I can do about the CAD model to help you out.

Oh, so you essentially welded the sides, then assembled the table with screws and taps, and then welded it together? was it mostly to prevent it from moving?
What about the legs, did you solder anything below the open 80x80 tubes? I cannot bolt the table down to the floor because i have floor hitting and i'm sure i'll be unlucky enough to hit a hose with the drill. Probably won't be necessary as the table will weight a shit ton.

Looking back over the photos in my thread, I can see why you thought it was just bolted. As it was my first time welding, I wasn't at all happy with how the process was going - I thought the welds were coming out pretty ugly and I had a number of "retries" grinding out bits that felt crappy and weak and doing them over again. As a result, I just didn't take many photos of the build during this stage, I was quite disheartened with it. It wasn't until I had something I was happy with (after lots of grinding, welding, regrinding, smoothing with some filler, sanding, then finally painting that I started taking photos of the frame again.

Lets start back here - October 2018, all the frame steels (bar one!) were cleaned up, tapped, bolted together into an assembly I was happy with.



I then turned the frame over, and started welding the caps on the bottom of the square tubing for the feet. I'd drilled and tapped these prior - but in hindsight I'd have welded a nut on the inside first to give more thickness to the thread. It was at this point I set my crotch on fire. ;)



By the end of the day I was quite happy with how it was sitting on its new feet. I'd also started preparing the steels for the adjustable height bed.



Then I started to tack weld the joints together all the way around, being sure to do one tack, then move around the machine to try and reduce distortion. Once that was done, I came back to each one in turn and gave it a full bead. Rinse and repeat.

I was so unhappy with it I literally don't have a picture of the frame until it was painted.... and even then I wasn't happy with the brush marks in the first coat, so that took a while to sort out!