Design & Build of Frankenrouter

[peteeng]

WOOHAA! Movement day - No sawdust or programmed moves but shaking down velocities and accels and any tight spots etc. All feeling good. XY all move smooth and at 5000mm/min (10mm pitch screws so 500rpm). Need to adjust gantry squareness. Tomorrow make a random program and clock up some Kms around the board.... calibrated roughly so moves 100mm as it should, Z was out by a bit but fixed that.... Onward to sawdust. Peter

[rodw]

Thanks Rod - excellent cast. He didn't cast a gantry! Please keep us informed. 5 axis is next on my list or an industrial robot style machine 7 axis. If Irb then cast concrete parts are the go as well. I'm waiting for some info from Sika AU about their high modulus grout... Peter

1220x1220 same size as Frankie but alot more mass! What concrete was used? Is the gantry 200x200x6mm ?

Concrete was Bluey LH60 https://www.bluey.com.au/products/blucem-lh60?

[peteeng]

Thanks Rod - Blueys the go. The LH60 is low exotherm same shrink as HE80 450ustrain... Peter

[rodw]

Pete, gotta say your router looks awesome now its together!

[peteeng]

Hi Rod - Just screwed the spindle on and it looks great. Tomorrow organise a bigger bucket for the pump and start the spindle. Then set up a run in program... I'm looking fwd to a cast machine. In 5 weeks Frankie goes to Portland Victoria to make surfboard fins. Then I suppose I start a Lanky thread... Peter

So far my only comment about Frankie is that I don't think I'd use round rails again. I'm used to using medium preload square and they are clearly stiffer, although the round was really easy to set up. The round rails yaw a little I think. So the gantry bearing spacing needs to be longer to get same yaw support. Other than that its turned out as expected. The price delta round to square is not significant in the build... I wanted to get experience with the round and the stack height is the same for the drive nut which was attractive as it made the gantry end detail simpler. But casting a gantry means I can get the geometry I want with no spacers so all good there. The pudding hasn't been eaten yet so onward to sawdust... maybe even some swarf... Peter

[rodw]

we were actually talking about spindle cooling in a small group I am in earlier in the week ( in relation to the concrete router above) and the cosensus was a chiller was the go. This one is well priced and includes the bucket!
https://www.vevor.com.au/water-chill...p_010721067131
I've bought from these guys a few times and they have quick delivery.

[peteeng]

Hi Rod - Yes a chiller would be good for cool bearings. I haven't bought anything from Vevor yet but I'm about to buy a small laser for a friend... Their prices seem to be good. Peter

[mactec54]

Hi Rod - Yes a chiller would be good for cool bearings. I haven't bought anything from Vevor yet but I'm about to buy a small laser for a friend... Their prices seem to be good. Peter

Vevor are just another sales site they don't manufacture anything just brand name other products, would never buy from them as there is no product support.

You don't need a chiller of any kind, with normal coolant flow these spindles barely get warm.

[rodw]

You don't need a chiller of any kind, with normal coolant flow these spindles barely get warm.

That wasn't the experience of my mate, maybe his router is a bit bigger but he said he was forced to upgrade from a pump in a bucket.

You can buy the same unit from aliexpress and get no support either. See how you go I guess.

[mactec54]

That wasn't the experience of my mate, maybe his router is a bit bigger but he said he was forced to upgrade from a pump in a bucket.

You can buy the same unit from aliexpress and get no support either. See how you go I guess.

May be his VFD Drive Parameters where not set correctly and causing it to overheat, they should only be warm to the touch, some have even said they don't use the coolant at all, but I would not do that, something else to remember not all of these spindles are created equal, there is some junk out there as well.

[peteeng]

Evening All - This afternoon I settled in Frankie enough to run a warm up program. Once the accels were right I was very happy at 5000mm/min or 500rpm with a 10mm pitch screw. Now playing with the motor tuning and tomorrow may make some sawdust just add water... to the bucket.

https://www.facebook.com/ScootCNC/vi...52650880738141

WOOOHOOO Peter

Well Frankie was started in Aug 21 so its been awhile. Now its Mar 23. The design changed half way through but result is good. So some tuning and sawdust then onto the next machine...

[peteeng]

G'day its sawdust time for Frankie. First dust made is good dust. The water cooled 800W spindle is quiet and fast. Now to tune the motion a little more and do some work with it... Peter

https://www.facebook.com/ScootCNC/vi...46125800405245

So the Frankie story is ending. I've decided what Lanky600 (or maybe called Half Lanky) will look like so that's for another thread another day... Then there's the Full Lanky after that... Maybe Short Lanky and Long Lanky. or Lankette and Lankie. Hmmm

[peteeng]

Hi All - I want to set up a test cut in aluminium for Frankie. I've been looking at chip loads and trying to decide a good starting point. I've decided to pick 0.15mm which means a feed of 2000mm/min and a spindle speed of 13000rpm. Does that sound reasonable? I'll have to find some chunks of aluminium to test. Peter

[Buoyen]

Your router looks very nice! Good job!

I would start at half of that chip load and increase from that.

If it's a quality carbide cutter you can go full rpm on a 6mm bit. But it needs cooling/chip evacuation.

[peteeng]

Hi Bouyen - Yes a 0.075mm Cl would need 1800 mm/min and 24000rpm. I'll get some aluminium plate and set up a test. Guhring have 0.037mm (0.6%) in their 1F 6mm table. Seems too small. And Suttons spec 0.016mm (0.3%) again seems to be way too small. But I'll test this out. Peter

amana are at the 0.0045" or 0.11mm mark. so feed would be 24000x.11= 2640mm/min

[Buoyen]

I think it is better to start below the recomended load (maybe 50% of the recommended chip load for the cutter you have).
A router is not as rigid as a VMC so can not do similar chip load.

When I look at the numbers again maybe even 0,075 is too high starting point for a 6mm but it depends on the width of cut you are starting with.
What tool do you have?

For a side cut (fusion 360s adaptive toolpath):
6mm depth of cut (Guhring says you can go 2xD, but we are still on a router)
1mm width of cut (using the numbers for 0.25xD to gain even more headroom)

-> multiply the specified chip load with 1.5

To start with I do not do that. So use the specified chip load in the table at 0,04mm/tooth.


https://www.guhring.com/ProductsServ...omResults=True

[peteeng]

Hi Bouyen - Its a tool bought from Adams Bits - Dia6mm 1F. I'll do say a 2mm DOC 100% width at some light CL then work heavier.... But I'll have to get some non gummy aluminium first... Peter

1 Flute UP CUT Carbide End Mill for Aluminium

[Buoyen]

Looks like they recomment 24k rpm and 800mm/min for 6mm WOC and 6mm DOC for their shortest 6mm bit.

That is 0,033mm/tooth. So maybe just start there with less DOC/WOC and increase as much as you can until the bit clogges up/breaks/chips or the finish gets horrible from melted aluminium

[peteeng]

Hi Bouyen,
From memory I have cut at 0.1mm CL before with an axial cut not a slot. But I thought I'd go:
Maybe a CL 0.025mm etc 300mm/min
1st cut CL=0.05mm Speed 12000rpm feed 600mm/min
2nd cut CL=0.10mm Speed 12000rpm feed 1200mm/min
3rd cut CL=0.15mm speed 12000rpm feed 1800mm/min

6mm bit 1F DOC 2mm WOC 6mm each run, I have few clogged bits here that need soaking in caustic.

I have to organise an air nozzle and some metal. Peter

[mactec54]

Hi Bouyen,
From memory I have cut at 0.1mm CL before with an axial cut not a slot. But I thought I'd go:
Maybe a CL 0.025mm etc 300mm/min
1st cut CL=0.05mm Speed 12000rpm feed 600mm/min
2nd cut CL=0.10mm Speed 12000rpm feed 1200mm/min
3rd cut CL=0.15mm speed 12000rpm feed 1800mm/min

6mm bit 1F DOC 2mm WOC 6mm each run, I have few clogged bits here that need soaking in caustic.

I have to organise an air nozzle and some metal. Peter

Be good to see how it runs with cutting aluminum, all aluminum grades machine fine some just need a different strategy, 6061 being the most used you should have no problems with it.

I watched your video, runs well, but was surprised at how much resonance there was, I though with the materials you used for the build, it would be very low.