First steps with a Shapeoko router table

I got my big sheet from:

**LINK**

They are between Bristol & Bath, I collected it.

These people:

**LINK**

are in Chigwell and cut to size though I don't think they are a stockist as such - but they can obtain it and cut to spec on a CNC router. They supplied a whole cut panel for a clock case I made. They could be a source of offcuts. I suggest a Googe search for Valchromat UK to find stockists who may be able to help - if they cut to spec they may well have offcuts that otherwise go for scrap.

If you are anywhere near Driffield in East Yorkshire I can fix you up with Some MDF, from my Joinery Manufacturing Business. Usually plenty of offcuts around.

Mark.

John and Mark,

Many thanks for your generous offers and info. Having got the router table into a working condition, I'm going to get some MDF from the local Wickes - just to get me started as I only need a piece about 50cm square.

As promised, I made a video and it's live on my YouTube channel. You can see how I got on by clicking here.

Warning: contains mistakes as well as the eventual success!

Enjoy!

John

Edited By JasonB on 23/04/2021 17:27:47

More progress today, in as much as I went to B & Q and bought some MDF and shelf brackets as part of the drive to make the installation look more aesthetically pleasing. I solved the lack of headroom problem above the router table by the simple expedient of folding up the feet on the Workmate. The result is the whole thing sits about 12cm lower and by putting a shelf above, the power supplies and laptop can be accommodated close to the machine.

Made the wiring a little neater by gathering pairs together and wrapping them in a cable tidy. Time will tell if that was a "neat" idea with respect to induced interference.

While I was at it, I reduced the length of the ER11 collet chuck shank to fit in the DeWalt 8mm collet and mounted it on the router. It reduces the vertical clearance a little, but, a) I can get some, if not all of it back by raising the router in the clamp and b) I have a greater choice of end mills and drills to use while retaining the standard ¼" collet and of course the 8mm one for larger jobs.

I have cut a piece of the MDF for a wasteboard and have some inserts on order, so when they come, I'll try out a bit of gcode to drill the pattern of holes in that. Before I do, though, there is a simple program that I can run to "prove" the system works. It involves tie-wrapping a permanent marker to the router and using the machine to make a test drawing on a sheet of A4 paper. I'll let you know how that goes.

That's all for now. Probably be next week before the next instalment appears.

John

Contrary to what I wrote above, I've run the test piece of Gcode from the manufacturers and here's the result:

Hope that works.

John

... Brought back fond memories of the Roland DXY plotter

MichaelG.

I've spent 4 days or more trying to learn Fusion 360 - specifically the 'Manufacture' section in order to produce some workable Gcode for the Shapeoko and I think I've done it - at least I've got some that gives a result.

First real-world project was to produce a sacrificial wasteboard to protect the supplied baseboard. I used MDF as intimated above to make a board which not only protects the baseboard but had a matrix of mounting holes at 50mm centres fitted with 6mm screw inserts which can be used for securing workpieces or workholding devices to the machine. Originally, the board was to be populated by 50 inserts - so that's what I ordered. As the design evolved the number grew and now it's a matrix of 81 holes (9 x 9) at 40mm spacing. So that's a further wait until the second batch arrives. Should've ordered 100 in the first place, but too tight!

Published another short video to show it in action:

Well, folks, things have moved on and sideways! I've been thrashing about with Fusion 360 trying to produce some Gcode for the router. The results seem to work OK in simulation so I tried something a bit (too) ambitious - cutting some aluminium. Sent off for some brand new carbide cutters ready for the onslaught and finished the wasteboard attachment. Buoyed up with my success with that, I looked forward to churning out lots of bits of CNC'd stuff. Oh, if only it was that simple!

First, I had to devise a means of securing the workpiece to the machine, so I dug out the set of low-profile clamps that I made for the mill. The attachment holes needed sleeving down to fit, so there's another delay. That done, I held the workpiece on both sides, not realising that the forces involved would be sufficient to dislodge it. Watch the video to see what happened. Suffice to say, it's time to stop, take stock and start again.

I'm going to re-align the workpiece with the router table, using a dial gauge or DTI and maybe put the vice from the shaper on temporarily to hold it, rather than using the clamps. I'll post a further report later, if there's still interest.

John

Thanks for sharing that ‘warts & all’ John

I’m sure it will set some sensible expectations.

MichaelG.

John my thoughts.

1st attempt way too much depth of cut for that machine particularly as using the full cutter width.

2nd attempt still too much depth of cut for this machine and far too slow a feed rate given the rpm. I'd also suggest rather than contour you think about doing some adaptive cuts first and then just very fine contour passes to finish both using a lot more of the side of the tool not just the end.

Looking at Creative3D video for a contour they suggest 16Krpm, 800mm/min feed for your 2 flute cutter, 0.4mm DOC.

For Adaptive, 16Krpm, 1600mm/min feed, 1.9mm DOC x 0.6mm stepover

Jason, that's just the sort of insight I need to make progress. I did slow the feed rate to 720mm/m but the depth of cut was obviously too much. Perhaps I should keep my experimenting under wraps until I get better results. But then no one would avoid the pitfalls I encountered on the way.

John

That second attempt looks a lot slower than 720mm/min, I count about six seconds to do a cut 25mm (4 x diameter) long so that's 250mm/min. Compare it with the first adaptive cuts on this part where I'm moving at 500mm/min

Edited By JasonB on 05/05/2021 15:55:48

Right again, Jason. I actually reduced the feed rate to 200 mm/m to try to replicate a similar speed to what I would have used when machining manually. And guessed the figure at that. I'm going to start over with a new piece of stock, held differently to ensure repeatability and accuracy.

I think I'l try holding a DTI with an 8mm mount in the DeWalt collet to check alignment.

John

John, although you may feed at 200mm on the manual machine your spindle is going so much faster on the router and a slow feed will result in the tool rubbing and not cutting well.

Fitting the vice should hold the part a lot better

I wonder if it’s worth putting a speed-controller on that router

MichaelG.

The downside to that is the feed will need reducing accordingly to keep the same low chipload and then the job starts to take a long time as the size of cut (width & height) can't really be increased due to the lack of rigidity.

When I worked it out in the other thread the Shapeoko should do a job on aluminium in a similar time to my KX3. It does that buy taking approx 3 times as many cuts in the same amount of time so if each of those cuts is 1/3rd of what I'm taking then total removal rates are similar.

The router is a vari speed one, not sure what John was adjusting it too but I would stick to No1 which is the minimum of 16K rpm and save the faster speeds upto 27K rpm for small cutters on wood etc.

.

I guessed so ... but I was thinking of rather less than 16K [perhaps with the addition of a cooling fan]

I’m pondering what might be causing those burrs

MichaelG.

Fellas,

The quoted no-load speed range of the DeWalt 26200 router I have are 16,000 to 27,000 rpm so I was running it at about 20,000 rpm off load. I think I'm being a tad too timid in my approach to feed rate etc so I'm currently doing some re-jigging of the gcode to reflect the info Jason has suggested. The vice mount will have to wait until I've fabricated some new clamps - unless I can modify the shaper ones. I'll look tomorrow.

Thanks to all,

John

Corrected spelling!

Edited By John Hinkley on 05/05/2021 19:49:13

Edit, posted before seeing Johns latest reply

Michael, I thought so as 16K is pushing it for a 6mm cutter but not sure if power would start to drop off if the speed came down too much. Two possible causes of burrs that spring to mind

1. No sign of burr at the beginning when it cuts across the corner before the work moved so could have damaged the cutter then

2. Looking again the router is set to speed No 3 say 22500rpm, combine that with a 200mm/min feed and a 2 flute cutter and that's a chipload of 0.004mm which is getting into the realms of rubbing, and not helped by dry cutting which may be welding metal to the cutter.

Edited By JasonB on 05/05/2021 19:50:59

Reminded me of the Plotmate I used with my BBC micro. I once made a rough and ready double-sided PCB using it with an etch-resist pen.

Neil