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Minnican
18-03-2011, 03:25 PM
Ok my learning curve continues.

I designed a simple house in CAD software, imported it to Vectric Cut2D to create the toolpaths and exported to Mach3 as part of my learning.

The house in the photo: http://www.flickr.com/photos/59593297@N07/5537454838/

is my 2nd attempt at using the software combo above.

Although generally happy, I noticed the edges of the 3.6mm ply used, are ragged and torn especially around the windows. I'm not sure why?

I used a 3mm ball nose cutter and think this may be part of the reason and think an end-mill may be better. Possibly the feed rate was too fast, or the cutter not sharp enough, or the ply not suitable? I'm not sure really.

I would be grateful for any suggestions at this point. Thanks.

Simon.

M250cnc
18-03-2011, 05:26 PM
Simon

maybe you could add your speed and feed so the correct feed could be worked out

Were you using an end mill ? for wood you should be using a router cutter

That ply you used is known as far eastern, and those splinters look normal for that stuff from B & Q ?

The best material would be Birch ply

Phil

wiatroda
18-03-2011, 08:43 PM
I think the issue is ply quality. I use to work for print finishers. They have been using cutting forms (steel shaped blades embedded in ply). This ply was real stuff and I don't think It would give so uneven edge.

M250cnc
18-03-2011, 08:46 PM
I think the issue is ply quality. I use to work for print finishers. They have been using cutting forms (steel shaped blades embedded in ply). This ply was real stuff and I don't think It would give so uneven edge.

Birch ply

Phil


Sent from my HTC Desire using Tapatalk

Minnican
23-03-2011, 04:04 PM
Two further questions.

Does anyone have any idea of a supplier of birch ply that delivers to Lincolnshire/East Midlands?

Are the cutters for metal and wood the same? If not, how can I tell the difference and where can I source wood cutters from?

Thanks in advance.

Simon.

M250cnc
23-03-2011, 04:20 PM
Does anyone have any idea of a supplier of birch ply that delivers to Lincolnshire/East Midlands?



Google search "birch ply suppliers that deliver to Lincolnshire" "birch ply suppliers that deliver to East Midlands"


Are the cutters for metal and wood the same? If not, how can I tell the difference and where can I source wood cutters from?

No they are different, but difficult to tell apart. So buy from a router cutter manufacturer like TREND amongst others.

Phil

ptjw7uk
23-03-2011, 05:49 PM
That fake plywood, usual stuff from B&Q is almost impossible to cut without feathering, even using a new cutter in a 24000 router.
Ive even had it show feathering using a power fretsaw and that useually cuts very clean!
Also a ball cutter is not the best to cut wood with, better to get a single edge cutter and up the speed if you can.
If you want to use the cheap(not these days) B&Q variety you can do it by varnishing both sides the day before, I used to do this when I built model boats, gives a very clean cut although costs for the varnish!

Peter

m.marino
23-03-2011, 07:45 PM
You can use endmill's to cut wood with, single flue are the best for wood if using an endmill. HSS router bits also work very well, though don't last as long with some types of wood. I completely agree on going to birch or another higher quality plywood. I get mine ordered from a mill in bulk here in Scotland which is of no help to you at all. Best of luck and the varnish works, it just adds an expense and the time for the varnish to set.

Michael

routercnc
23-03-2011, 10:21 PM
I use quite a few of these Silverline TCT cutters. Cheap with a reasonable cut:

http://cgi.ebay.co.uk/1-4-SHANK-STRAIGHT-CUT-TCT-ROUTER-BIT-cutter-6-x-20mm-/150456912442?pt=UK_Home_Garden_PowerTools_SM&hash=item2307ee4a3a

I've also recently bought, but not yet used, a spiral cutter a bit like this one. They shear the wood rather than rip across the fibre.
http://www.trend-uk.com/en/UK/trend/content/content_detail.php?record_type=Knowledge&id=15884

AdieR
24-04-2011, 10:38 PM
Quick question regarding the rags on your windows, are you cutting only on one side? Rags can occur on "breakthrough", where your cutter goes through the material. Have you tried / is it feasible to cut on one side about halfway and turn it over?

Robin Hewitt
25-04-2011, 12:49 AM
There is a reason why router bits don't have a helix on the cutting edges, as you just discovered :heehee:

The helix adds an upward component to the cut.

Minnican
25-04-2011, 12:41 PM
I've bought a down-cutter but haven't tried it yet. Been too busy making solar panels, wind turbines and solar cookers!!

Jonathan
25-04-2011, 01:16 PM
I've bought a down-cutter but haven't tried it yet. Been too busy making solar panels, wind turbines and solar cookers!!

Nice, I've made all of them too! Probably the main reason I made my CNC router is to do wind turbine blades. Bit off topic, but here's the solar panel (tracking parabolic mirror etc) I made a few years ago:

3977

Got any pictures of what you've made?

Edit: Thought I'd add something on topic. Before I got router cutters I did once have to use a normal milling cutter on plywood - it did make a huge difference.

wiatroda
25-04-2011, 03:20 PM
Bit off topic, but here's the solar panel (tracking parabolic mirror etc) I made a few years ago:
Got any pictures of what you've made?

Jonathan, very nice mirror. Does it have sun tracking system ??
Minnican, yes I want to see some pictures as well :) Very interesting subject

Jonathan
25-04-2011, 03:32 PM
Jonathan, very nice mirror. Does it have sun tracking system ??

Yes it does - that's what the small PV on the top right powers. There's a small geared motor with a linkage to track the mirror. The mirror rotates on bearings placed around the focal pipe. You can just about see the temperature in that image - that's in Celcius. I've seen about 160C on it. I will post a better picture later when I've found it.