:drunk:Decisions, decisions!
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:drunk:Decisions, decisions!
My latest thought is to bolt down a 20mm aluminium plate to the top of the steel raised area (shown in photo). I will then use the machine to skim the surface flat. Then I will use the machine to drill a grid of holes which I can then tap (maybe the router could do this??) for holding jigs and fixtures.
A plate with holes in should work well. But I don't think the WC spindles have enough torque to tap directly? However, you can try thread milling using a special cutter (~£40), plus your CAM will need to be capable of a spiral cut with user parameters on the pitch:
Forward to 12:23 to see thread being cut:
https://www.youtube.com/watch?v=a43S2y7Ccy8
Can't imagine that plate is flat enough to be useful and could cause you more trouble than it's worth.?
Personaly I would just buy Machine tooling plate that is ground perfectly flat. Put your Profile etc directly on this and then shim out any error using the nice flat surface for reference. No need to skim flat. Then you can drill tap matrix of holes. Forget tapping with router type spindle no where near enough torque or control to do this unless thread milling. It's nothing of job to do with spiral flute tap in a Cordless drill.
Try these people. I deal with Lincoln branch but believe they have place in WH that will give you a quote and you'll find the price of Machine tooling plate isn't that much more than normal plate. Being Cast plate it's much more stable and being ground it's obviously flat so is worth the extra IME.!
http://www.ascmetals.com/
Here's Some I prepared earlier.!!
Attachment 16414
Thanks Jazz! Would I get away with 15mm?
I think I need to sit down and consider reducing the size of my machine. I don't envisage (famous last words) doing any large wood projects etc. A bed size of ~400mmx400mm would be more than big enough. Costs would be reduced across the board and I would have more room to manoeuvre around the machine in the shed! The biggest downside I see is that I already have THK linear rails I purchased a few years ago which would need cutting down. Seems a shame to cut them (also, I'm not sure how easy that would be!?).
Yes some times best to sit back and re-think before jumping in.
Ask your self what's the main purpose of the machine going to be.? Be realistic and honest with your self. If it's mostly wood then you don't need go to the trouble of expensive plate.
Your original design sat on nice flat stable surface will work ok for most woods, plastics etc. If it's aluminium then yes the strength and accurecy is needed so the costs rise.
Regards cutting rails then it's always something to avoid really purely on being a waste. The actual cutting is easy. All you need is angle grinder with 1mm thin cutting discs and you'll whiz thru them.
Been said many many times on forum with lots of examples and this is think towards Steel if you want cheap and strong. But slight warning here.!! IME trying to make something from the scrap bin work, like what you found, always ends in a compromise of some kind and in the grand scheme often doesn't save you much money long term so be weary of this appealing route.!! (That said Steel offcuts etc are ok just avoid structures for bases etc)
Agreed. I've always struggled with being a perfectionist and over-designing things!
While I have your very valuable attention, do I need to go with "Heavy" extrusion over "light"?
Booked tomorrow off work so hoping to spend some time on this now I've got some other projects out the way.
I've been looking at stepper drivers too. Think I'm going with the AM882/EM806. It looks like Aliexpress is the place to get them, just need to find a "reputable" seller... On the subject of buyign things, I can't seem to find the bloke in China who was the go to person for ballscrews etc? His eBay shop was something like "linearmotionbearings2008" ???