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Rogue
04-09-2011, 10:53 PM
As part of the overall strategy for my planned CNC build, I want to consider how to support it.

I don't currently have a proper workshop, so I'm using a room in the house. This means that I have to consider limiting as much vibration and noise as possible. I don't expect to eliminate it completely, as lovely as that would be, but the less of a nuisance it is then the more I can use it!

I'm planning a fairly hefty wooden bench for this room to replace the "cheap B&Q workmate clones + mdf clamped to the top" that currently serves as my reloading bench. If I'm planning to put a CNC router/mill on the bench as well, what kind of things could I do to make it more bearable for the rest of the house?

I've read that some designs are more likely to channel vibrations into the floor which would be a definate problem, but I've not found advice on reducing this that works for my situation (including material availability and skill level) yet.

I've got a basic design that I plan to follow, though I'll upscale the legs to increase mass which I'm hoping will help. The design also uses multiple layers of MDF for the benchtop. Would changing this to an array of 2x4's with some MDF on top for a smooth surface be more suitable? More mass, different densities - these are all things that vibration hates, I believe? Might need some bloody long bolts for the bench vise and pillar drill though :lol:

I'm also aware that some kind of freestanding cabinet is a great way to muffle sounds and keep the mess in one place. That's something that I plan to include as well, and would welcome any input from people who have been down that road!

Any tips, advice or experience that I could draw on would be greatly appreciated. For the avoidance of doubt, I should make it clear that my woodworking experience is somewhere around zero, so possibly advice in language that a novice can understand or at least google successfully would be appreciated!

Robin Hewitt
04-09-2011, 11:08 PM
Suggest you try RS...

Mechanical Products and Tools
- Mechanical Components
- Anti Vibration Mounts and Feet

See what is available then shop around.

Rogue
04-09-2011, 11:18 PM
- Anti Vibration Mounts and Feet


£30 a foot? Not too sure I love the wife and kids that much :whistling:

Actually I forgot about RS, I think they have some stuff within my budget that would be useful as part of the overall reduction strategy. Thanks :tup:

Rogue
04-09-2011, 11:56 PM
Thinking about it... issues with steppers vibrating have been solved by using "rattlers", I remember people attaching magnets to anvils to reduce the noise, a white paper I read recently said that more bolts reduced vibration... so would it be feasible to incorporate something into the mill design (or table design in this case I suppose) that would help? Not just adding mass, but moveable mass in the same way the "rattler" uses loose components to work?

Robin Hewitt
05-09-2011, 09:36 AM
Steppers don't rattle unless you full step them, they purr.

The noise is the spindle motor and the tool hitting the workpiece. Only annoying if high frequency.

If it's a mill you should be fine sitting it on fat rubber feet.

If it's a router, your only hope is an accoustic hood :whistling:

Rogue
05-09-2011, 12:16 PM
I think the expression used elsewhere was "It's not a router, it's a bed mill..." :lol:

Rogue
05-09-2011, 12:34 PM
The noise is the spindle motor and the tool hitting the workpiece. Only annoying if high frequency.

So in relation to an acoustic hood, would it be fair to say I only need to consider materials that will deal with the higher frequencies instead of being affective across a broad range of frequencies?

Jonathan
05-09-2011, 06:02 PM
Steppers don't rattle unless you full step them, they purr

I think 'rattlers' may have been referring to dampers you put on the motors which allegedly reduce resonance?

I think the rest of it is negligible compared to the noise/vibration caused by cutting.