slim_boy_fat
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So, you didn't have space for the Mycentre 4? 
- Thread starter Screwdriver
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Screwdriver
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So, you didn't have space for the Mycentre 4?
I did ask...
Screwdriver
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Damn, that thing is HEAVY!
It has two precision ground surfaces underneath but I am struggling to see how that might be useful. I will need to be very careful with the design of the base and especially the casters. I dread to think what would happen to the floor if it fell three or four feet onto it. Probably go right through...
S.
It has two precision ground surfaces underneath but I am struggling to see how that might be useful. I will need to be very careful with the design of the base and especially the casters. I dread to think what would happen to the floor if it fell three or four feet onto it. Probably go right through...
S.
Screwdriver
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Quick question for the welders out there. If you could have a table that did this, what are the advantages. Basically is it worth the bother for me to (redesign!) the structure to enable it to safely tilt up to 90 degrees.
The bed itself weighs a whopping 350kg I reckon so it has to pivot around it's centre of balance. I realise the rough sketch needs more gussets and whatnot. The bearing will run off a 40mm spigot. It will need a brake or possibly a winding mechanism for when the bed has vices and workpieces attached. At the moment it simply spins. I could conceivably design a dynamic pivot height adjuster to keep it at the centre of balance but first things first.
Since the bed is clearly capable of maintaining its rigidity, I thought I might as well capitalise on that strength which allows me to simply hang it from either end.
What do you all reckon?
Screwd.
The bed itself weighs a whopping 350kg I reckon so it has to pivot around it's centre of balance. I realise the rough sketch needs more gussets and whatnot. The bearing will run off a 40mm spigot. It will need a brake or possibly a winding mechanism for when the bed has vices and workpieces attached. At the moment it simply spins. I could conceivably design a dynamic pivot height adjuster to keep it at the centre of balance but first things first.
Since the bed is clearly capable of maintaining its rigidity, I thought I might as well capitalise on that strength which allows me to simply hang it from either end.
What do you all reckon?
Screwd.
Screwdriver
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There are a zillion ways I could do it and there are clearly many advantages, just wondering if there are any I haven't thought of. Haven't actually done much welding yet!
I am working on a rotator too but that won't have to mount on the table. The table will need a vice of course but that can go on the T nuts. I am planning on making it a desk height table largely because of the weight (it will be on retractable casters) but I might give it say 500mm of height adjust.
S.
I am working on a rotator too but that won't have to mount on the table. The table will need a vice of course but that can go on the T nuts. I am planning on making it a desk height table largely because of the weight (it will be on retractable casters) but I might give it say 500mm of height adjust.
S.
Screwdriver
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Yes I will have to be wary of it overbalancing but it is relatively narrow (and I am keeping it low) so I could just extent the feet slightly further out.
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That's an excellent idea IMO. It needs some slotted plates to bolt it in position securely, like this:
One on each side with a big bolt on each should lock it nicely. I would bolt it to the floor if possible too, so it can't tip over.
One on each side with a big bolt on each should lock it nicely. I would bolt it to the floor if possible too, so it can't tip over.
Screwdriver
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I think the comments about having it bolted to the floor are correct. It would take too much bracing and the legs would have to come out too far to make a caster version stable enough. Here's the latest thinking.
Tilt because that's fairly easy with such a stiff table and height adjustable once I figure out a sensible mechanism for a hydraulic jack or geared chain pulley. The table must operate and lock from one side only. I am considering two lengths of acme thread under each pivot with a home made HDPE nut - maybe chain drive though the large crossmember to operate the simultaneously.
S.
Tilt because that's fairly easy with such a stiff table and height adjustable once I figure out a sensible mechanism for a hydraulic jack or geared chain pulley. The table must operate and lock from one side only. I am considering two lengths of acme thread under each pivot with a home made HDPE nut - maybe chain drive though the large crossmember to operate the simultaneously.
S.
Screwdriver
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So long as the mechanism is secure the sheer weight of this thing will provide stability. I may make something like axle stands to hold it up, might even use actual axle stands! Tilting can be held rigid with a simple hydraulic brake and disk off a motorcycle, I have tons of bits like that around.
The tilt doesn't need to be powered, just held rigid with at least two mechanisms, a big foolproof physical lock then the brake system as above. It will also need to be damped and may need some mechanical advantage for when there is heavy stuff bolted to it. Either that or a heavy adjustable counterbalance hung underneath.
Height adjustment would be nice to have but not essential. I'm still thinking it all through so its all just wishful thinking anyway....
Screwd.
Bill Edwards
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I'd just use a linear actuator such as this http://www.ebay.co.uk/itm/Multi-fun...442131?hash=item51dcc7f213:g:DhYAAOSwp5JWYZpt
Powerful enough to cope with unbalance if something isn't centered right (which is a risk with anything you stick on a welding bench), no risk of anything going wrong for the operator, and it'll hold it as well without requiring a separate brake.
Powerful enough to cope with unbalance if something isn't centered right (which is a risk with anything you stick on a welding bench), no risk of anything going wrong for the operator, and it'll hold it as well without requiring a separate brake.
Screwdriver
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Thanks Bill. I had no idea they were so affordable with that spec.
S.
S.
