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fspearman1
03-28-2012, 06:05 PM
I have seen several references to grounding the machine.

Where would you attach the grounding wire?

Digitalwoodshop
03-28-2012, 06:53 PM
I use a ground wire with 3 Gator Clips on each end. On the Machine, I attach to the infeed table, my copper dust collector and the foil hose. On the other end 2 places on the grounded dust collector and on the foil hose. I realize the infeed table does tilt up so the connection is not the best... Sometimes like now when I have the right side metal cover off to expose the X Gear Box for quick access, I clip it on the metal frame rather than the foil hose.

One time I was doing a Cut Path and I hear a Snap, Snap, Snap... I look in and a spark of static is going from the copper dust collector to the 1/8 inch cutting bit.... I saw the collector ground wire was off... Hooked it back up and the Snap stopped... The Flow of dust through the collector causes the Static.

Good Luck.

AL

PCOutlaw
03-28-2012, 09:26 PM
As far as grounding my CC, I took an ohmmeter to all the screws on the machine and found one on the bottom that had the best connectivity throughout the machine. Connected a ground wire on that and then ran the ground wire through the hose going through my vortex and my duster, which is actually connected to a ground rod outside of my woodshed. I have direct connectivity from my CC to the ground rod. The screw is behind the bottom plate of my CC.

52088520895209052091

bergerud
03-28-2012, 09:50 PM
I would like to understand exactly how the machine electronics is vulnerable to static discharge. It seems to me that the metal casing of the machine must get a charge from the dust collection system and then the casing discharges somehow to the electronics. Since the machine does not have a ground wire, I assume the discharge is through the electronics to the power wires. If this is true, grounding the machine to the dust collector might not be good enough. The dust collector and the machine could both be charged and there would be the same danger of discharge through the electronics. I seems to me that the most effective thing would be the have the casing of the machine simply grounded to the wall ground. Connecting the machine to the dust collector may stop sparking between the collector and the machine, but I am not sure that protects the electronics.

I am by no means any expert on this. I am not even sure whether the machine gets a positive or negative charge. I assume that electrons are "rubbed" off of the dust and the machine (as well as the dust collection system) gets a negative charge. To be safe, I think we only need to give these electrons need a easy path out of the system.

I hope someone out there is an expert on this and can enlighten us as to how exactly the electronics gets damaged and to the best method to protect the electronics against discharge.

fwharris
03-28-2012, 10:22 PM
Since my DC-INSERT is all metal and attached to the metal frame with the 2 4mm screw holes and the hose I use is the expandable aluminum drier vent hose I just clip my ground wire to the hose clamp at on the insert.

The ground wire is wrapped about the hose back to the dust collector. I've ground the dust collector frame to the shop ground.

I use the drier vent hose for a couple of reasons. It is light weight and easy to move around when I do need to remove the insert from the machine and it is metal. Being metal makes it less prone to static build up like some of the plastic hose.

fspearman1
03-29-2012, 06:31 AM
Thanks for the replies.
I just got the ringneckblues DC. I don't understand using an aluminium hose. I thought that aluminium was one of the worst conductors. Also with the other comment about why the electronics is so prone to static.
I think we need LHR to step up and give some direction on this.

chief2007
03-29-2012, 07:14 AM
Something I would like to see added to the improvements list for the Carvewright is to add a 3 wire power cord verses the 2 wire power cord and have an internal grounding system run in the machine. This would add additional ground protection to the machine. I have always wondered why is it isn't that way already as I think every computer out there uses a 3 wire power cord system.

Might be something to look at doing to my Old A machine and see how it goes - of course would talk with the techs at LHR first for any precautions.

dbfletcher
03-29-2012, 07:35 AM
If I remember correctly it had something to do with getting the Underwriters Laboratory (UL) seal for the machine. Using a three wire cord would of caused them headaches. I think there is a thread about it somewhere on here. If I find it I'll post the link.

I'm not sure if this is the thread I was thinking of... but it does mention it. I'll look for a better explaination tho.

http://forum.carvewright.com/showthread.php?7608-3-prong-plug&highlight=3+prong

chief2007
03-29-2012, 07:39 AM
Thank much for the info - db,

Steve

fwharris
03-29-2012, 09:53 AM
Thanks for the replies.
I just got the ringneckblues DC. I don't understand using an aluminium hose. I thought that aluminium was one of the worst conductors. Also with the other comment about why the electronics is so prone to static.
I think we need LHR to step up and give some direction on this.

Thanks for being a DC-INSERT owner! :cool:

I went with the drier vent hose initially for it's light weight and easy to handle vs. the heavy dust collection hose. As for the conductivity of aluminum I can not speak to that but the head of the CW is cast aluminum.
s

fspearman1
03-29-2012, 10:07 AM
Got the insert yesterday.
I see that there is a lot of aluminium on the machine. That's why I believe that LHR needs to give some direction on grounding. After all, they designed the machine and should be able to better answer the question.

Dan-Woodman
03-29-2012, 10:11 AM
My origanal machine back in '06 had a 3 prong plug. I think UL didn't like it.

DickB
03-29-2012, 10:17 AM
All modern electronics are susceptible to ESD (electrostatic discharge) damage. The geometries of these electronic devices are microscopically small and it takes only a very low potential difference to cause an unwanted discharged that can do damage. The input/output pins of these devices typically are fabricated with protection circuits, but there is a limit to what they can shield. Power supplies are also typically designed with devices to protect against voltage spikes, but again they have limits. I don't know that the CarveWright is any more susceptible to EDS damage than say a laptop computer, but the fact that we move dust around in the machine can provide an environment for static buildup and discharge.

The numerous cables and wires from motors, switches, keypad, and sensors provide conductive paths to the circuit boards, so a discharge near any of these can readily be transmitted to the circuit board.

I think the best strategy to prevent ESD damage is to prevent static buildup and discharge by grounding the machine to earth ground. Personally, I have grounded my machine by connecting a wire from the metal head casting to my dust collector, and the dust collector is grounded by its 3-prong plug.

bergerud
03-29-2012, 10:22 AM
Aluminum is a good conductor. The wires bringing power to my house are aluminum! As far as static (which is high voltage very low current), any metal is a good conductor. The conductivity of different metals is only a factor if one is trying to pass large currents.

Digitalwoodshop
03-29-2012, 02:20 PM
I am betting LHR will be silent on this issue of Machine Grounding and for LEGAL Reasons.... The UL Certification Process resulted in the machine going from a 3 wire to a 2 wire.... Any Change Recommendation made by LHR would make the Lawyers at LHR loose SLEEP.... It's part of the Certification Process to make a Product SAFE for Consumers.... And the Various Categories of Certification..... I will bet that LYNN will avoid giving any advice on this topic for Legal reasons...

Now for the question as to how the Static can harm the machine.... Since the machine has a power supply it takes 115 volts AC and makes it into 5 Volts DC to run the Electronics like the Computer and sensors. And I believe 24 Volts DC to operate the SERVO Motors if I have that correct. I have never actually measured it...


When Static is produced by the action of dust moving through the collector hood and hose it produces the Static Electricity. Electricity always seeks a path to Ground and in seeking that path TO Ground it as in a 10 Thousand Volt Static Charge will see the 24 or 5 volts as a potential less than it's own charge and arc to it in an attempt to get to ground. Having a 10 Thousand Volt Charge enter a electronic circuit like the Board Detector, Servo Electronics, Cover Switch Circuit, or any other Wire on the machine is like you holding a Boom Box Speaker to your Ear and letting a Blast of Sound GO. It is Overwhelming to the EAR... And Burns out Electronics.... Especially Capacitor Coupled CMOS Electronics.... There are at least 2 forms of electronic logic chips.... TTL or the early Transistor to Transistor Logic or the later CMOS or Consolidated Metal Oxide Semiconductor that use a Spark Gap sort of Capacitor input.... This Capacitor can be harmed by the higher voltage... It Punctures Holes through the two separate plates of a capacitor rendering it useless.

So here is MY take on Machine Grounding and Static Electricity....

IF we have a Static Electricity Generating Device on our Machine then it is best for us to give the Static a EASY path to GROUND. IF we don't ground the machine or use a Shop Vac inside the machine and get that "Thrill" of the feeling of Wood Chips flowing through the Shop Vac Hose... Really just Static Electricity building up on your BODY like when you SCUFF you feet on Carpet in School and touch the back of someones EAR in Class and hear the SNAP..... Your BODY for a period of time held a STATIC Charge until you Grabbed the Door Knob and heard the SNAP or your Friend EAR.... The SAME can happen with the machine...IT can have a Static Charge build up on the metal parts and since it is NOT grounded through the Power Cord, the Potential or Voltage will build up to the point that it SNAPS inside the machine.... Destroying the Computer.... or LCD Display.... Hence the Posts... I don't have any dust collection and I stopped the 50 hour project and using my Shop Vac sucked out 20 pounds of Sawdust with my Shop Vac, NOW the machine is DEAD.... How many times have we seen a post similar to THAT....


So the FIX in My Opinion.... Ground the machine in a few areas and in MY opinion to the Dust Collector as it will ALWAYS BE a 3 Wire Grounded machine... Weather it is a 115 Volt or 220 Volt Machine..... They all have a Ground Wire.... And that ground wire is connected to the Power Company Ground at your Power Meter. Yes, the Wire to the House is Aluminum but that is done due to cost.... Copper is a BETTER Conductor and that is why it is always used in House Wiring except for a period in the 70's when Aluminum Wire for Homes and Buildings was authorized.... That ended BADLY... Electrical Outlet Screws that work great with Copper now use for Aluminum Corroded and made the Junction Heat Up as more current flowed through the outlet. Electric Heaters were the worst... You always hear of Heater Fires in OLD Homes.... But many were started in the WALL..... The Outlet Screws heated up and melted the WIRE.... The Aluminum was BANED in homes and Buildings. Aluminum Wire needs to be Thicker than Copper for a Given Voltage and Amperage as it conductance is less than copper or the resistance to the flow of electricity...

Ground LOOP.... And we don't want anyone to drive a 12 foot Copper and Steel Ground Rod into the Ground next to your machine and attach a Wire to the machine.... That will produce a problem called "Ground Loop" that is the difference in potential or voltage between the Power Company Ground and your new Ground ROD.... The New Ground Rod could actually have VOLTAGE on it.... It's a scientific fact.... Proven by Electronic Test Equipment... Any Electricians here will know that a Sub Panel of your House Wiring like a panel in your Wood Shop or Garage will NEVER have the Grounding Bonding Screw Engaged..... Only in the Main Panel....

So here is more reading about this set of topics...

AL

http://www.pcworld.com/article/82184/avoid_static_damage_to_your_pc.html

http://en.wikipedia.org/wiki/Static_electricity
http://www.kpsec.freeuk.com/components/ic.htm
http://en.wikipedia.org/wiki/Aluminum_wire
http://en.wikipedia.org/wiki/Ground_loop_(electricity)

fspearman1
03-29-2012, 02:55 PM
I sent an e-mail to support and asked the simple question of what method to use and where to attach.

Since LHR will not stand behind their product if it's not grounded then they should tell us how to ground.

Just as the warranty says you can not modify the machine in any way (cut the plastic cover?) I was told if I bought the dc I can cut the cover and it would not void the warranty. That's not written any where but if that's the case it should be.

Maybe I'm being picky here but my take is if I sell a product and indicate a certain procedure needs to be followed then I have the responsibility to tell how to do that procedure.

cnsranch
03-29-2012, 04:51 PM
I've talked to LHR - you can cut the cover and not lose the warranty.

I have Fredrik's dust collector with a small HarborFreight dc set under the machine. 4" dc hose from collector to collector. Stranded copper wire fed thru the hose, attached to the dust collector under the machine, the other end attached just under the machine's cover where the threaded holes are.

fspearman1
03-29-2012, 06:55 PM
I've talked to LHR - you can cut the cover and not lose the warranty.

I have Fredrik's dust collector with a small HarborFreight dc set under the machine. 4" dc hose from collector to collector. Stranded copper wire fed thru the hose, attached to the dust collector under the machine, the other end attached just under the machine's cover where the threaded holes are.I

I understand from LHR that you can cut the cover also. But, there is no documentation that this cna be done therefore if there is a warranty issue you could be out of luck. According to eveything I have read it is null and void if you do any modifications. I personally think that LHR should document what can or can not be done.

fwharris
03-29-2012, 07:46 PM
I

I understand from LHR that you can cut the cover also. But, there is no documentation that this cna be done therefore if there is a warranty issue you could be out of luck. According to eveything I have read it is null and void if you do any modifications. I personally think that LHR should document what can or can not be done.

When I was getting everything set up for selling my DC-INSERT I specifically asked this question on the machine warranty. The response I got was:

Cutting the cover did not void the machine warranty as long as it did not by pass/modify any of built in safety features (cover switches). I was asked to post this statement: NOTE: disabling or modifying any safety features on your CarveWright/CompuCarve is not endorsed by LHR Technologies, Inc.

AskBud also had to include this statement for his dust collection project.

I was also asked to include this statement in cover modification instructions:
NOTE: This product requires modification of the clear cover. After modification, do not operate the CarveWright/CompuCarve machine without the DC Insert installed, or without an unmodified cover.



I was also informed that IF a customer had to send their machine back to LHR for repairs that LHR would be required to install a new clear cover before they could send the machine back to the customer do the the UL certification that they have for the machine. The customer should also inform LHR that they wanted their modified cover returned.

Hope this helps clarify your questions about their stance on the machine warranty. If not keep on asking!!

fspearman1
03-30-2012, 08:34 AM
When I was getting everything set up for selling my DC-INSERT I specifically asked this question on the machine warranty. The response I got was:

Cutting the cover did not void the machine warranty as long as it did not by pass/modify any of built in safety features (cover switches). I was asked to post this statement: NOTE: disabling or modifying any safety features on your CarveWright/CompuCarve is not endorsed by LHR Technologies, Inc.

AskBud also had to include this statement for his dust collection project.

I was also asked to include this statement in cover modification instructions:
NOTE: This product requires modification of the clear cover. After modification, do not operate the CarveWright/CompuCarve machine without the DC Insert installed, or without an unmodified cover.



I was also informed that IF a customer had to send their machine back to LHR for repairs that LHR would be required to install a new clear cover before they could send the machine back to the customer do the the UL certification that they have for the machine. The customer should also inform LHR that they wanted their modified cover returned.

Hope this helps clarify your questions about their stance on the machine warranty. If not keep on asking!!


My last comment on this thread.....NO WHERE does it say that LHR endorses modifying the cover. I am sure that if you send your machine in for repair and LHR puts a new cover on it that you will be charged for the cover.

Nuf said....let's get carving!!!!

Digitalwoodshop
03-30-2012, 09:34 AM
Nuf said.... is an understatement....

lynnfrwd
04-16-2012, 12:24 PM
Boy, where was I on this one.

If you send in a machine that has a modified cover for a DC insert, we will NOT require you to buy a new cover. We do have a Release of Responsibility Form for you to sign.

smv1978
05-16-2012, 10:30 PM
The dust collector hood I made was completly made from Plexiglass.. I removed the old hood (leaving it untouched) and made a new one. I have pics of it here:
http://forum.carvewright.com/showthread.php?20660-Do-not-leve-your-CarveWright-unattended&p=177173#post177173

You are welcome to use this design .. the main piece of plexiglass is a flat piece I heated and bent to fit the CarveWright like the old hood .. then I was able to cut and add the the dust collection into the new hood I made. Most parts where glued togther with hotglue (which worked suprisinly well) then I used brush style weather strip for all the seal points. I also used the 2 threaded points that were in the Carvewright allready (on the shelf in front of the chuck) to attach everything that need to be attached. The threaded hole where everything was attached is also where I grounded it (after reading these posts I kinda wonder if that was a good place) my Vacume hose had a wire coiled around it which is where the ground was hooked to.

Doing it this way meant I could return the CarveWright to its orignal condition.

gapdev
05-17-2012, 02:39 PM
Before I read this:


If you send in a machine that has a modified cover for a DC insert, we will NOT require you to buy a new cover. We do have a Release of Responsibility Form for you to sign.

I purchased 2 new Covers for my 2 machines with Floyd's DC, just in case I ever needed them. Took a couple of months to get them.

Kenny

fwharris
05-17-2012, 03:40 PM
Before I read this:


I purchased 2 new Covers for my 2 machines with Floyd's DC, just in case I ever needed them. Took a couple of months to get them.

Kenny




Kenny,

If I recall correctly that is around $65.00 each!

gapdev
05-17-2012, 03:51 PM
Floyd,


If I recall correctly that is around $65.00 each!

Yea, but I was under the impression that if the machine ever had to go in for service, I would be required to buy one, and I thought that maybe it also voided the warranty.

Oh well. Doesn't hurt to have them, I guess.

Kenny

fwharris
05-17-2012, 03:59 PM
Floyd,



Yea, but I was under the impression that if the machine ever had to go in for service, I would be required to buy one, and I thought that maybe it also voided the warranty.

Oh well. Doesn't hurt to have them, I guess.

Kenny

Kenny,

I hear you on that one, at the time that was the policy for if and when ever one had to send the machine in for any work. If you need/want to recover some of your cost you might try posting them for sale.

lynnfrwd
05-17-2012, 09:20 PM
They are about $20.


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fwharris
05-17-2012, 10:27 PM
They are about $20.


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Connie,

Is that for just the clear cover or for the full cover assembly?

lynnfrwd
05-17-2012, 10:44 PM
Clear cover.


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fwharris
05-17-2012, 11:23 PM
Clear cover.


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Thanks! :)

gapdev
05-20-2012, 02:59 PM
They are about $20.

Not if you buy them from Sears, which I did because I had some Credits with them. Sears charges $47.99 + shipping and tax, total = $62.70.

Oh, and Connie, Sears has this wonderful thing called On-Line Ordering. Go on-line, look up your part, and purchase it.:mrgreen:

Sorry, I'm being a smart ***, I know, but I really do wish you guys would get with the 22'nd century and allow us to buy all or most parts online.

Kenny