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... took 3 of us to lift it on there... but its very stable and has levelling feet to level it all up... quite pleased with it...
The levelling feet were off ebay and they screw into home-made mounts comprising an M12 nut welded to a 50mm square x 4mm steel repair washer recessed into the bottom runners
Did you get planning permission for that?
Looks solid enough, when will you CNC it? :beer:
lol... its robust enough to need it tho... and my wife wasnt impressed when she realised just how much space this thing was going to take up :)Quote:
Originally Posted by Robin Hewitt
its pretty solid 3 x 4" PSE and M12 bolts, was going to paint it but not sure I can be bothered now...
CNC'ing this one may be a while... got to finish the smaller one first, and Borris is still waiting for his Z-spindle to be fitted... and funds are a tad lacking re ballscrews etc... I've got £250 of tooling to be picked up first...
I think I'd add a diagonal brace or two. The thought of 300kg + on top of two pairs of legs (i.e. front and back) with only a bar at the bottom for stability would worry me.
Bill,
I understand why you'd think so but I dont think it needs it. The mill base is bolted into the cross-members with 8" long 1/2" coach bolts and the cross members at the bottom are similarly bolted to the side runners. The centre of gravity is directly between the legs. As part of the testing before I put the mill on the base I put it on end (so the legs were horizontal) and stood on the end of the legs without it budging.. and I weigh 76kg. For the legs to fold therefore it would need more than 76kg of side force and would have to rip the 1/2" coachbolts out of the wood.
I will be putting some side members on to support an intermediate shelf for the tooling and that will add further fore-aft integrity.
regards,
Irving...
If you just box in the sides with ply, that will do the trick Irving. It will also give you a rather nice enclosed cabinet for your tooling too. Bookshelves get a very large part of their strength from the usually very thin back panel and they can be loaded well in excess of 300kg :) If I was back at work I could run it through Solidworks FEA package for you but knowing you, you have done your sums on it :)
Regards, Jeff.
I did do a certain amount of analysis including checking the Euler buckling load for the legs - there's a 100% safety margin there... :DQuote:
Originally Posted by Smiler
Anyway as of this evening my son helped me put the head on (he's a foot taller than me and works out so he was able to lift it up while I stood on a ladder and manoeuvred it into place), its all levelled, motor is installed and the whole thing runs silently.... all I need now is some tooling!
I was also noting that some bracing was missing.
Here is the base i made for my Rockcliff Machine to sit on: Link Here
:beer:
Dont see any bracing on yours either Lee... :DQuote:
Originally Posted by Lee Roberts
"Your both...FIRED !"
Here's pic of the mill on its stand... (sorry its so tiny but thats a limit of the forum... Lee - needs fixing soon)
I keep getting a mad urge to drop a few chunky spiral reinforcement rods down inside the column of mine, then top it off with a rich cement mix. The rods are there ready for next time I'm doing concrete.
You have excellent access to plug the bottom of your column and do the same. Could be useful :D
And the benefit would be??? I'd imagine a modicum of additional stiffness? Kip is looking at a square column conversion for his which sounds interesting. He's apparently talking to an iron foundry, presumably because its too big a casting for him to do...Quote:
Originally Posted by Robin Hewitt
Ah! You are still at the "this is a chunky looking hunk of iron" stage of your development.Quote:
Originally Posted by irving2008
Bliss :beer:
You been trying those big cuts again Robin...Quote:
Originally Posted by Robin Hewitt
:D
Big cuts are fine so long as your screws are tight enough to prevent the dig in. You just make it oversize for the big cuts. I'm actually amazed how much metal these mills can hog out without breaking the tool, usually when it throws a wobbly and decides to plough off in some unexpected direction.Quote:
Originally Posted by irving2008
The time when you feel the flex is when you're going for that fine finish. It turns a corner, a sympathetic vibration sets in and you start to wonder if another few hundred lbs of metal might not be a really good idea.
I'd also fit backlash free splines in the column if only I could get it apart :D