Dust Collection

Dust Collection

Postby Larry Stobbs » Sat Dec 10, 2016 8:13 pm

I ordered a new HD4 and ordered the dust collection boot that they make for it. I got it in and the "adapter" to hook your dust hose up to it is too big for the hole that they machined in the dust collection boot. So far I have not been able to get NWA to respond to my emails on that issue, but the literature they sent talked about grounding the dust collection hose so the static electricity didn't end up frying your electronics. I ordered the anti-static hose that Rockler sells, I am just curious if anyone knows if this should take care of the issue without having to run an extra grounding wire? I obviously don't want to have a static discharge damage something but I have not used a dust boot system before, my smaller CNC I had in an enclosed cabinet but the new CNC is to big to do that.
Larry Stobbs
Vectric Craftsman
 
Posts: 100
Joined: Tue Apr 07, 2009 2:00 am
Location: St. Joseph, Missouri
Model of CNC Machine: CNC Shark

Re: Dust Collection

Postby Xxray » Sun Dec 11, 2016 1:05 am

I know you should, but I have never grounded my hose in 5 years and never had an issue.

So don't assume that everything is going to fry without grounding.
Doug
User avatar
Xxray
Vectric Wizard
 
Posts: 1929
Joined: Thu Feb 17, 2011 8:47 am
Location: MI USA
Model of CNC Machine: CAMaster Stinger 1

Re: Dust Collection

Postby Adrian » Sun Dec 11, 2016 11:23 am

A lot depends on what you're cutting in my experience. When I first started I was cutting pine, oak, maple and cherry mainly and never needed any grounding of any sort. Then I started machining MDF and plastics. The machine would regularly go haywire so I grounded the machine to a four foot copper spike outside the workshop and grounded the dust hose to the workshop earth. Never missed a beat since.
User avatar
Adrian
Vectric Archimage
 
Posts: 9369
Joined: Thu Nov 23, 2006 2:19 pm
Location: Surrey, UK
Model of CNC Machine: ShopBot PRS Alpha 96x48

Re: Dust Collection

Postby COWBOY1296 » Sun Dec 11, 2016 3:02 pm

Grounding is not one of my most knowledgeable topics. I figured that since my bot and dust collector were grounded via their plugs that i was ok. Everything worked fine until recently and then i started to have com issues I think brought on by static in dry Colorado. I then ran a ground wire between my bot and the dust collector and now have over 130 hrs of cutting without issues.
COWBOY1296
Vectric Wizard
 
Posts: 650
Joined: Thu Apr 15, 2010 10:03 pm
Location: SOUTH CENTRAL COLORADO
Model of CNC Machine: SHOPBOT BUDDY PRS 32, 4 FT PWR STICK

Re: Dust Collection

Postby Larry Stobbs » Mon Dec 12, 2016 2:41 am

Thanks guys, I am still waiting for my new NWA HD4 to get here, it is supposed to ship next week. I have an original white CNC Shark that I have ran forever but was only cutting walnut and Cherry. The big reason for getting the new one was to do bigger projects but my former dust collection was a large wooden box with plexiglass doors on it so when you closed it up the dust collection fitting on one end of the box sucked everything towards the one end and into a collection bag. With that set up there was no way for static electricity to travel from the dust collection system to the CNC machine but this new machine is way too big to do that. I am still having a hard time getting NWA to respond to me about the dust boot they sent me not being cut correctly and if they don't get that resolved I may have to send the part back and try to find someone that sells a dust collection boot for this system. I tried Dixie billets but they just make the nice clamp for the router. I may go ahead and ground this setup anyway after hearing about a super PID speed controller, they say you need to ground that system so may have to do it anyway. Thanks for the responses
Larry Stobbs
Vectric Craftsman
 
Posts: 100
Joined: Tue Apr 07, 2009 2:00 am
Location: St. Joseph, Missouri
Model of CNC Machine: CNC Shark

Re: Dust Collection

Postby IslaWW » Mon Dec 12, 2016 2:58 am

Larry...
Here is an excerpt from a dust collection article I wrote a few years back:

Static Reduction in CNC Dust Collection Systems



Dust collection systems are one of the primary generators of static in woodshops. This static becomes very problematic when the dust collection system is connected to a CNC cutting tool. For those CAMaster owners that have experienced issues caused by static discharge, getting a reasonably priced solution is often difficult to come by. The following should give those users a viable option.

Static is generated by air and dust movement in a non conductive hose. I have used metal ducting to solve a number of static related CNC control issues. The following instructions explain the use of light gauge home improvement store type galvanized 4" ducting in place of the often used flexible plastic dust hose. The advantages of metal ducting are as follows:

• Metal ducting is installed grounded and "drains" any static charge carried inside by the particles
• Increases flow due to less restriction than flexible hoses
• Gives a reliable ground path out to the flex hose at the machine and allows it to be grounded well
• Properly installed, forms an anchor point for the flex hose to attach to

When you install a metal duct system to a CNC machine you should:
• Use as large diameter pipe as can be connected to the dust collector housing, reducing diameter as distance increases.
• Run the metal duct as far as possible, i.e., run it out to over the CNC table in the center 8 to 10' high
• Screw the fittings to the collector housing and to each other
• Tape the joints to reduce leakage
• Verify that the dust collector itself is actually grounded to the electrical system ground
• Make sure that the metal duct is grounded by adding a ground wire to the electrical system or collector housing (if needed)
• Use a 4" flexible dust hose with an embedded wire. DO NOT USE AN ALL PLASTIC HOSE
• Use the shortest length of flexible hose that allows full movement to table extremities
• Make sure that the embedded wire from the flex hose is attached to the metal duct with a screw and crimp connector.
• In high altitude, low humidity, or problematic locations an additional stranded wire run thru the hose may be required. This must also be connected to the ground screw along with the embedded wire from the flex hose
• Do not allow the dust foot end of this wire to come in contact with the metal parts of the CNC machine

Note: Along with the dust hose drain wires, it may also be beneficial to make sure that the dust hose itself has been insulated from any of the CNC components by at least 1/2". This can be done by providing a support near the top of the X or Z plates that work both as a strain relief AND an insulator. When cutting high static producing materials the charge inside the hose can build high enough to discharge thru the hose onto the frame. This problem most often comes to light when surfacing and an errant (charged) hose comes in contact with the machine.
Gary Campbell
CNC Technology & Training
The Ultimate Woodworking Machine
GCnC411 (at) gmail.com
User avatar
IslaWW
Vectric Wizard
 
Posts: 1244
Joined: Wed Nov 21, 2007 11:42 pm
Location: Marquette, MI, USA
Model of CNC Machine: The Ultimate Woodworking Machine


Return to Hardware related questions

Who is online

Users browsing this forum: No registered users and 3 guests