If you have a Torchmate system and you already have it up and running you will be able to appreciate this thread. And for those of you who are waiting on your system to show up, you might want to follow this.

The very first project on my TM3 made me realize that I MUST do something about the smoke and sparks created when the machine is in action. After seeing the smoke settle and feeling the grit on my teeth (yeah, you know what I am talking about) I started wondering what the hell I am doing to my health, let alone my other shop equipment.

While I am sure that there are many solutions, I know that many people use a downdraft setup or a water table. I NEED to do something and I would like to see what others have done.

I suppose the information needed in the thread would be as follows:


First, what size table are you running (Mine is 5x10)



Downdraft:


How do you capture the fumes below the table
What size duct work are you running
What size blower motor (HP, CFM, etc)
What type of blower (squirrel cage, standard exhaust fan, etc)
How do you keep small items from falling into your DD
How do you retrieve the small items that do fall through (not a big deal on small tables, but it is an issue with a 5x10)
How do you clean/filter the exhaust or do you

Water table:


How deep is your basin
Can it be raised and lowered
How often do you change the liquid
What can be added to keep the liquid from freezing
How far away from the top of the support slat's is the surface of the water
How do you keep small items from falling into your WT
How do you retrieve the small items that do fall into the liquid
Does the basin need to be grounded (I don't know if that is a stupid question or not)



What, if any, are the pro's and con's of each system and which do you prefer?

I know that this is not a complete list of questions, feel free to add your own.

And as always, pics are appreciated.
:smokin:

Water table:


How deep is your basin
6"-This was mostly dictated by the fact that I already had 5" slat material.
Can it be raised and lowered
No, I was in such a rush that I actually didn't even put a drain plug in it. I figured once the weather warms up it would be due for a cleaning. At that time I will just put a pump in it to get it down and if needed drill a hole in the place I'm going to put the drain hole.
How often do you change the liquid
What can be added to keep the liquid from freezing
I'm heated when I work out in the shop but it only gets down to about mid 30's unless I go several days without working in the shop.
How far away from the top of the support slat's is the surface of the water
I try to keep the water really close. If I can keep it within 1/4" or less the dust is pretty much non existent.
How do you keep small items from falling into your WT
Right now I don't, I just let them fall and then cuss like hell as I fish around in the rust water looking for small pieces.
How do you retrieve the small items that do fall into the liquid
Right now I put on a pair of chemical gloves so as not to cut the hell out of my hands on the dross built up on the top edges of the slats.
Does the basin need to be grounded (I don't know if that is a stupid question or not)
I'm not sure and I don't think it is a stupid question either.



What, if any, are the pro's and con's of each system and which do you prefer?

I know that this is not a complete list of questions, feel free to add your own.

And as always, pics are appreciated.
:smokin:

To add to that, I TIG welded my entire table together and it really blew. Roughly 27' of tig weld while laying on my stomach or trying to sit on my elbows and knees. I used a solid bottom sheet and then used rips for the ends and sides. I thought about having the sides fabbed in a large brake but they wanted something insane to do it so I opted for the more painfull and cheaper route. To keep everything straight I cut out some dog bone shaped gusset braces and welded them all the way around prior to welding in the seams. After all the seams were welded I had my wife stand in the basin to hold it down to the frame while I laid under the table and welded it to the frame.

I know what you mean about the gritty nasty dust. I'm pretty sure I'll be wiping the crap off everything for a year or two from the bit of cutting I did before I built the water bed.

I will throw in some simple, important information on both a Downdraft and Watertable setups.

Downdraft:

Recommend volume for your downdraft fan. The square footage of the table x 125 in Cubic Feet a Minute. So a 5x10 table = 50 sq ft x 125 = 6,250 CFM fan.

Skirting the legs around the bottom of the table is the easiest as it required just flat panels attached to the frame. The front panels are easily removable to retrieve parts and sweep up the dust/scrap.

Most downdrafts ventilate to an outside atmosphere and don't use any kinds of filters. Depending on your local regulations, Plasma smoke from certain materials may be Hazardous waste. Check your local regulations!

There are recirculative systems with filters that can reuse your in shop atmosphere, they are very nice to have as you are not ventilating your heat or air conditioning outside the shop.

Pros: Efficient removal of smoke and light dust, with no ill effect on the cut itself. No water near the material so flash rusting is not an issue.

Cons: Large Fan, uses electricity to make the fan move. Potentially large amount of ducting going somewhere. Accessing underneath the table for parts retrieval. Less effective depending on where your duct is in relation to where you are cutting.


Water Table:

We recommend that the water be able to come to the top of your slat's, and have at least 1" of clearance between the bottom of your slats so that the water may move freely underneath them.

The closer the water is to the material, the better the collection of the smoke and dust is.

With a regular air/air plasma (think hand cutters) there is no obvious deterioration of the cut quality, although some have reported it gives them more dross.

We do not recommend cutting aluminum over a water table, when the aluminum hits water it creates Hydrogen gas. This gas can build up underneath the plate and cause micro explosions.


The slurry from a plasma water table may be hazardous waste depending on the material you are cutting, check your local regulations when disposing of this.

Pros: Highly effective, passive solution. Simple tub design, easy to build. Parts are cool to the touch and can be removed easier. Helps keep material warping down.

Cons: Water is in contact with the material, causing flash rusting. Parts retrieval can be a bit more difficult fishing parts out. The debris builds up on the bottom of the tank and needs to be cleaned. Cutting Aluminum is not recommended.

Great tips guys. So far I haven't done anything other than using welding blankets to skirt the bottom of my table. This does nothing for fumes, but does keep most of the crap from spreading over the whole shop floor. When I move into the new shop next month I'm planning on setting up a downdraft setup that goes to a vent I had built into the wall. I'll be watching this thread for ideas for sure.

Thanks for the info HardcorewannabeXJ. I had sent some PM's to Tim from LII and asked him a few questions about his water basin. He said that he was going to switch to a downdraft. I wonder how much water splashes out when you are cutting near the edge of the table and the edge of the material.

I talked with a colleague of my dad who is in the barge business and he had some experience with CNC torches. The company he works for, CGB, has parts fabricated for the barges locally. He said that the fab shop has a CNC setup that has a downdraft that has a series of louvers that open and close as the torch passes down the table, allowing them to have a much smaller fan requirement. It may be too complicated to build for what it is worth, but it would be interesting to see. I'll try to get him to take me by the place and I'll see if they will give me more information on it.

Larger machines have the louvers that open and close as the torch moves the length of the table. Pretty nice feature, maybe something torchmate could work into the software eventually w/ sensor and solenoids at each vent?

As far as using a down draft and exiting out the side of the building. It will not take long and your building will be brown all over the outside and it is a nasty dust to try and clean off. Just powerwashing it will not remove it from steel siding.






Thanks for the info HardcorewannabeXJ. I had sent some PM's to Tim from LII and asked him a few questions about his water basin. He said that he was going to switch to a downdraft. I wonder how much water splashes out when you are cutting near the edge of the table and the edge of the material.

I talked with a colleague of my dad who is in the barge business and he had some experience with CNC torches. The company he works for, CGB, has parts fabricated for the barges locally. He said that the fab shop has a CNC setup that has a downdraft that has a series of louvers that open and close as the torch passes down the table, allowing them to have a much smaller fan requirement. It may be too complicated to build for what it is worth, but it would be interesting to see. I'll try to get him to take me by the place and I'll see if they will give me more information on it.

Some of these are not as detailed as what I would like to see, but they kinda give a better idea about what is being talked about.

Downdraft

http://www.torchmate.com/Torchmate%20skirted.jpg


http://www.torchmate.com/plasmaresized_med.jpg
(i think that that is a downdraft system....)


http://www.torchmate.com/fulltable.jpg


http://www.torchmate.com/Rick%20Troxel%201.jpg


http://www.torchmate.com/product3bLarge.jpg
(not a TM from my understanding)

Water Basin

http://www.torchmate.com/aptsize.jpg


http://www.torchmate.com/july2009lg.jpg


http://www.torchmate.com/Ronnie_Welborn_lg.jpg


http://www.torchmate.com/April_photo.html
(appears to have a heavy amount of antifreeze in the basin)

As far as using a down draft and exiting out the side of the building. It will not take long and your building will be brown all over the outside and it is a nasty dust to try and clean off. Just powerwashing it will not remove it from steel siding.


Good to know, I was thinking about having ductwork exit our pole barn, which happens to be a steel building. This is kinda why I was wondering if the exhaust needs to be filtered/cleaned.

Large units use a filter system / 50 gal barrells to fill up w/ that dust. Some scrap yards will take the dust some will not. Mainly depends on how close a relationship you have with them.


Good to know, I was thinking about having ductwork exit our pole barn, which happens to be a steel building. This is kinda why I was wondering if the exhaust needs to be filtered/cleaned.

Thanks for the info HardcorewannabeXJ. I had sent some PM's to Tim from LII and asked him a few questions about his water basin. He said that he was going to switch to a downdraft. I wonder how much water splashes out when you are cutting near the edge of the table and the edge of the material.

I talked with a colleague of my dad who is in the barge business and he had some experience with CNC torches. The company he works for, CGB, has parts fabricated for the barges locally. He said that the fab shop has a CNC setup that has a downdraft that has a series of louvers that open and close as the torch passes down the table, allowing them to have a much smaller fan requirement. It may be too complicated to build for what it is worth, but it would be interesting to see. I'll try to get him to take me by the place and I'll see if they will give me more information on it.

Larger machines have the louvers that open and close as the torch moves the length of the table. Pretty nice feature, maybe something torchmate could work into the software eventually w/ sensor and solenoids at each vent?

As far as using a down draft and exiting out the side of the building. It will not take long and your building will be brown all over the outside and it is a nasty dust to try and clean off. Just powerwashing it will not remove it from steel siding.

The Torchmate X Series table has an integrated ventilation system that "chambers" the area of the table to where the gantry is currently cutting, allowing a less powerful fan to remove the smoke and dust only near the torch, as to not be sucking through the clean air in the areas of the table.

Large units use a filter system / 50 gal barrells to fill up w/ that dust. Some scrap yards will take the dust some will not. Mainly depends on how close a relationship you have with them.

Torchmate sells a complete ventilation system complete with filters and a stand to put a 55 gal drum underneath so that when the filters are purges using reverse air pressure, the dust falls into it.

Here it is pictured below, we used this system in house heavily for months of production cutting on our Torchmate 3. It was equipped with dust drawers at the bottom instead of the 55 gal drum however. It runs off of 460 3 phase, but I believe can be ordered to suit.

http://torchmate.com/air_filtration_system/airfilter2.jpg

http://torchmate.com/air_filtration_system/index.html

5x10 TM3 table

I'm most likely going to do a water bed and here is what my thoughts are on it.

Make the sides, say 4" tall and the slats 2". Run water to the top of the slats, so the water is actually just touching the material - I'm going to be doing a lot of thinner stuff for the wife's art biz as well as my thicker stuff.

The reason for the taller sides is so that it doesn't splash out of the basin while cutting near the edge.

The shallowness of the water should make it very easy to recover parts.

For the solution, I was just going to use RV antifreeze. It's cheap, readily available and non toxic.


yea/nea??

As far as using a down draft and exiting out the side of the building. It will not take long and your building will be brown all over the outside and it is a nasty dust to try and clean off. Just powerwashing it will not remove it from steel siding.

Thankfully that's the side of the building that's against a fence and I cant see it :flipoff2: I was planning on using a couple furnace filters on the vent to keep the dust down though.

Do not have a torchmate system, but I thought I'd give some input on our system we use in our prototype shop.

First, what size table are you running (Mine is 5x10) : 4' x8' table

Water table:

How deep is your basin: Roughly 1 foot
Can it be raised and lowered: Yes, but we never do
How often do you change the liquid: Everytime we need to cut aluminum it gets drained and cleaned, usually ends up being every 3-4 months (probably gets used about 50-100 hours between cleanings)
What can be added to keep the liquid from freezing: Nothing, we're in a heated shop
How far away from the top of the support slat's is the surface of the water: 1/2 to 1 inches
How do you keep small items from falling into your WT: We don't yet, we just fish them out when we're done with the sheet
How do you retrieve the small items that do fall into the liquid: Magnet is okay, but usually I just reach in, feel around, and grab them up.
Does the basin need to be grounded (I don't know if that is a stupid question or not): Nope, we just run the ground cable to the workpiece on the table.

Over time, the water level goes down, and once it gets below 3-4 inches below the workpiece, it'll start emitting significant amounts of smoke and dust, so we'll just add some back. It's also nice because the parts come of the table quite cool right after cutting.

5x10 TM3 table

I'm most likely going to do a water bed and here is what my thoughts are on it.

Make the sides, say 4" tall and the slats 2". Run water to the top of the slats, so the water is actually just touching the material - I'm going to be doing a lot of thinner stuff for the wife's art biz as well as my thicker stuff.

The reason for the taller sides is so that it doesn't splash out of the basin while cutting near the edge.

The shallowness of the water should make it very easy to recover parts.

For the solution, I was just going to use RV antifreeze. It's cheap, readily available and non toxic.


yea/nea??

Depending on how thick your material is and your slat thickness, 2" tall slats seems like it'll be a bit undersized to hold much of anything up unless you run another row of slat supports down the center. I'm considering doing that on mine when ever I drain it as mine move too much when shifting material around on the slats. When the slats move back and forth sometimes it creates a nice little wave that splashes over one end. Had I built my sides a bit taller I probably wouldn't have anything to worry about.

Depending on how thick your material is and your slat thickness, 2" tall slats seems like it'll be a bit undersized to hold much of anything up unless you run another row of slat supports down the center. I'm considering doing that on mine when ever I drain it as mine move too much when shifting material around on the slats. When the slats move back and forth sometimes it creates a nice little wave that splashes over one end. Had I built my sides a bit taller I probably wouldn't have anything to worry about.

Our table runs 3" tall slats with 3 main crossmembers across the table to support them. The outside steel sticks up about an inch above the slats, and I wish is was maybe 1/2" to 1" more to reduce water spillage during moving and cutting near the edge.

Depending on how thick your material is and your slat thickness, 2" tall slats seems like it'll be a bit undersized to hold much of anything up unless you run another row of slat supports down the center. I'm considering doing that on mine when ever I drain it as mine move too much when shifting material around on the slats. When the slats move back and forth sometimes it creates a nice little wave that splashes over one end. Had I built my sides a bit taller I probably wouldn't have anything to worry about.

Our table runs 3" tall slats with 3 main crossmembers across the table to support them. The outside steel sticks up about an inch above the slats, and I wish is was maybe 1/2" to 1" more to reduce water spillage during moving and cutting near the edge.

yeah, that's what I was thinking, having 3-4 slats going the other way to keep the other slats upright.

The thickest I will be doing with my own stuff is 3/4". So I'm not sure just how much support I'll need. What's a 4x8 sheet of 3/4", 1000 lbs?

You also need to consider how much of the slat gets cut away by the plasma passing across it. I have 3" slats on my table, and a few of them have gouges 1" deep in them. Dont know WTF I was cutting when I did that, but weight carrying capacity isn't the only thing to think about.

If you're just trying to save on material cost....dont bother. My slats have been in my table since day 1, almost a year and a half ago and they are just getting bad enough that I'm gonna replace them next month when I move. IMHO that's a pretty decent lifespan.

You also need to consider how much of the slat gets cut away by the plasma passing across it. I have 3" slats on my table, and a few of them have gouges 1" deep in them. Dont know WTF I was cutting when I did that, but weight carrying capacity isn't the only thing to think about.

If you're just trying to save on material cost....dont bother. My slats have been in my table since day 1, almost a year and a half ago and they are just getting bad enough that I'm gonna replace them next month when I move. IMHO that's a pretty decent lifespan.

I forgot all about my original thinking on the life span of 5" slats. When they get too nasty I'll have plenty of material left to just flip them over.

I guess I can weigh in on some tec here. Our plasma/oxy table runs an average of 8 hours a day between both shifts. I do most of the programing and cut most of the really heavy plate.

How deep is your basin? Its 6" at the front and 8" at the back.
Can it be raised and lowered? Yes, we have an air baffle like a submarine, that way you keep using the same water, you use air to push the water out of the bottom and into the table basin.
How often do you change the liquid? Been there 7 years or more, I don't think I have ever seen it changed.....
What can be added to keep the liquid from freezing? Heated shop.
How far away from the top of the support slat's is the surface of the water? We have the ability to completely submerge 2" plate. I do all of our plasma cutting with the water even with the top of the plate. I do all of our oxy/mapp cutting with the plates submerged up to 2" and as much as I can get on the thicker stuff. (We cut up to 10")
How do you keep small items from falling into your WT. We don't....
How do you retrieve the small items that do fall into the liquid. With our hands.....
Does the basin need to be grounded (I don't know if that is a stupid question or not) I would say yes, we do not ground to the work, we have grounds on the table. (And about 20 other places grounded to a copper rod buried 20 ft in the ground to keep the computer alive.)


Hope that helps.

Just found a video from about 3 years ago of some submerged cutting.

YouTube - plasma table under water cuts (http://www.youtube.com/watch?v=stM57oXarWY)

What's a 4x8 sheet of 3/4", 1000 lbs?

in theory its more like 979.776 lbs.... :flipoff2:

Have your cutting tech put a magnet on the pieces that will fall through before they fall through, and you wont have to fish them out...

like on a smaller tab, after 1/2 the profile has been cut, put a magnet spanning the already cut edge, and the part wont fall through...

You also need to consider how much of the slat gets cut away by the plasma passing across it. I have 3" slats on my table, and a few of them have gouges 1" deep in them. Dont know WTF I was cutting when I did that, but weight carrying capacity isn't the only thing to think about.

If you're just trying to save on material cost....dont bother. My slats have been in my table since day 1, almost a year and a half ago and they are just getting bad enough that I'm gonna replace them next month when I move. IMHO that's a pretty decent lifespan.
No, just trying to keep a shallow basin for ease on fishing parts. I already have a bunch of 5"? (4 or 5, i'd have to measure) slats now that could be moved to the water table if/when I go that route...
in theory its more like 979.776 lbs.... :flipoff2:

lol I was just guessing based on what I just paid for a 4x8x3/8" sheet.