grinding dust and electronic welders etc

[youngdylan]

Finally got my hands on an induction heater. I'm not allowed to swear anymore .... even with **sterixs so I can't do some loud whoops of joy.

My workshop is microscopic and I do a LOT of grinding/ finishing etc and I haven't got space for a grinding room. I'm kinda worried about those metal particles finding their way into the heater (and other electronic stuff like my TIG and plasma cutter). A lot of this kit has a fan that draws cooling air in. Wondered how others deal with the dust whilst still allowing the kit to "breathe" and stay cool. I had a one year old Lincoln invertec TIG go down on me. It was repaired under warranty but it was still dissapointing. I'm beginning to suspect it was the dust of death.

Thinking along the lines of a car or motorcycle air filter over the fan inlet. Opinions/suggestions ?

[Sam Thompson]

I've had problems with the dust etc. smothering the cooling fins on heat sinks on rectifiers (?) in welders and found that the easiest way to deal with it was to open the box and get it out manually (or by hand if you find that easier). After a while the number of screws in the cover becomes 'rationalised' and the job gets quite quick. I don't know what that would do to a guarantee on new gear though. It's odd but even in an industrial environment, fluff is what causes the damage.
I blow compressed air through the vents of grinders, drills etc. occasionally and it's amazing how much c##p comes out, if even a small part of it was actually in the works I like to think that I'm prolonging the life of the gear.
The most nagging problem that I've found with grinder dust is that it starts rust very easily and in a dampish environment will badly mar an anvil if left over a weekend.

[pkrankow]

For a welder..I can't help.

I have dealt with computers and dust before. The best answer is to open and clean on a regular basis, blowing out with dry or canned air. Using a substantial filter can prevent air flow and cause more problems because computer fans are not very strong. With metallic grinding swarf prevention of entry is important because most computers are not protected from surface contact on the inside. In the shop at school, the computers were in a dirty environment case with additional fans and filters, or in a seperate room from the lab. For construction dust, primarily gypsum dust and saw dust, regular cleaning is fine, although surprising amounts of dust will be packed in after a few weeks in a construction environment.

For your welder and other shop equipment, I would expect that there are coating to prevent surface contact so regular cleaning with dry compressed or canned air would be adequate, but takes time out of your schedule.

Phil

[Timothy Miller]

I blow out my welding machines every 6 months or so. I have never had one give me problems from dust. My welder repair man showed me years ago at my metal working first job about 15 years ago. There is an amazing amount of dust that accumulates in those machines. But I think welding machines are probably engineered to handle a bit of dust. I cant speak to induction machines as i have no experience with them.

[arftist]

Since your induction machine is essentialy a forge, is it safe to asume it is fixed in one position in your shop, or is it portable. If fixed, I would run a duct to clean outside air, an inlet if you will as oposed to the traditional exhaust. The simplest of plenums from said duct should protect your machine.

[youngdylan]

Since your induction machine is essentialy a forge, is it safe to asume it is fixed in one position in your shop, or is it portable. If fixed, I would run a duct to clean outside air, an inlet if you will as oposed to the traditional exhaust. The simplest of plenums from said duct should protect your machine.

Thanks for the responses people.

It's actually going to sit on a plate on top of the coal forge because with the type of work I mostly do the induction heater/ reosebud torch nozzles/ gas forges should do the bulk of the hard work. I've thought about mothballing the coal forge but think I'll use it once in a blue moon .... so the induction heater will need to be moved every now and then

Yeah Arftist, Plenum for dust etc to settle in sounds good. Taking the inlet to the oustside may be a problem though so maybe plenum chamber drawing air from the workshop with air filter on the inlet ???? Vehicle air filters are quite high flow and easily replaceable ... it's a question of which filter. Things like K&Ns might get burnt by the shower of sparks from a grinder.

I had a quick peep inside and the circuit boards don't seem to be laquered and there are some exposed metal leads etc. If a tiny bit of metal/grit etc landed and shorted across the wrong two bits .........

Yeah regular maintenance/blowing out is good but my big worry is that the metallic particles in the grinding dust (that have been ground away by the grit) are conductive, a lot of the leads on modern chips are minute and I could blow and lodge a particle into the wrong place.

I took a video of it in action, will post on you tube (when I learn how). It heated a bit of 40mm up to where is was sparking and starting to burn in a round a minute. Photo shows it doing the same to a bit of 30mm in around 30-35 seconds. IT ROCKS

[clinton]

I always remove the sheet metal when I purchase a used welder and blow it out with compressed air, amazing what you can find inside a machine, my tig welder had a mouse living inside at one time but it was pretty crispy when I blew out the machine. A maintenance schedule to blow out dust in welders is a good idea in any shop, more grinding = more frequent, I would not recommend a filter on the machine it would likely restrict the air flow. You could cover a welder to prevent dust from entering when not in use, welding blankets or a canvas tarp work good

[Mainely,Bob]

For tough environments and delicate equipment we have built boxes to house gear in and made one side of the box a filter element by using either a slip in furnace filter or made a frame and stretched on the same material we used for the dust collection bags in the woodworking shop.
The gear was placed in the box and the air draws thru the filter element.To clean just slide the filter element out,blow it off(outside) and slide it back in.
The boxes were sealed using weatherstripping to make them air tight.
Easier to clean the filter every other day and keep the rig clean than pull the case of the machine apart and wave an air nozzle around in there among all that high tech and high dollar electronic stuff.

The old "smoke eater" type smoke/air filters that use a series of electronically charged plates were the hot ticket for a while and still come up from time to time for cheap at auction.
You have to lift a door,slide the plate bank out and hose it off to clean it and that may be inconvenient for the previous owners but we found they work really well and you are not chucking filters out to the land fill every time you turn around.
We mounted them up high,in the corners and pointed them so the outlet pushed the air from one along the wall toward the other.In small shops we mounted one or two and put plywood baffles in the remaining corners to keep the airflow going.

[youngdylan]

For tough environments and delicate equipment we have built boxes to house gear in and made one side of the box a filter element by using either a slip in furnace filter or made a frame and stretched on the same material we used for the dust collection bags in the woodworking shop.

Second time today somebodies refered to furnace filters. I started the same thread over at the NWBA and Gene C mentioned them. What are they? I'll do a google but have you got anymore info, links. Thanks Bob.

I'm beginning to move towards the idea of drawing the air for the fan through a plenum (big box) that that allows any dust that gets past the filter to settle awith maybe a furnace filter at the inlet. I'm asuming since these are for furnaces they can take a bit of heat and general workshop punishment and are quite high flow. Having the whole kit in a box would make it awkward getting at the controls etc. As ever, whatever I do, the limited space in my workshop will dictate the design.

[pkrankow]

the 3M hepa furnace filter is about $10 each for a 15x25 inch at lowes or home depot. I use the "allergen reduction" filter that is the next step down and about half the price in my house(red package, 3M) ....but you are on the wrong side of the pond aren't you.

These filters go in the cold air return of the homes heating and cooling system for forced air. Typically they are a 1 inch pleated "paper" with a reinforcement to resist air pressure. They can also be made from fiberglass, but that is a lesser material. There are also washable varieties.

Phil

[Mainely,Bob]

If you make the box with a filter on the two long sides you can usually find a flat pleated filter that will slide into place.If a furnace filter(think thick window screen with filter paper in place of the screen)is too large then look at flat air filters for cars or even a large round filter for a shop vac hose clamped on top.They make washable ones of all these types of filters.I know how touchy your vegan girlfriend is about the re-use/recycle thing.

The controls are reached from the front of the box by leaving the front opening fitted to the face of the machine and sealing it with weatherstripping.Most of the high tech gear we came across had the fans and vents in the side or back so sealing the front/control panel was not a problem.
Alternately you could sail off the edge of the earth and put the gear into an old bead blasting cabinet and make adjustments looking thru the window with your hands in the gloves.
I`ve NEVER been known to take a good thing too far.Nope not me,but man MUST have high quality motivational tunes while performing mundane tasks(like sand blasting) in order to keep his sanity or what remains of it. ;)

[Sam Thompson]

Those big air-con units on public buildings often have large pleated paper filters that are changed on a maintenance programme, whether they need it or not. It may be worth approaching the caretakers at cinemas. hospitals etc.

[HWHII]

Finally got my hands on an induction heater. I'm not allowed to swear anymore .... even with **sterixs so I can't do some loud whoops of joy.

My workshop is microscopic and I do a LOT of grinding/ finishing etc and I haven't got space for a grinding room. I'm kinda worried about those metal particles finding their way into the heater (and other electronic stuff like my TIG and plasma cutter). A lot of this kit has a fan that draws cooling air in. Wondered how others deal with the dust whilst still allowing the kit to "breathe" and stay cool. I had a one year old Lincoln invertec TIG go down on me. It was repaired under warranty but it was still dissapointing. I'm beginning to suspect it was the dust of death.

Thinking along the lines of a car or motorcycle air filter over the fan inlet. Opinions/suggestions ?

When I was working in a large fab shop We had 75 invertor power sources and have seen many shorted out boards due to grinding dust, even on the newer one that have sealed boards. The only thing I have seen work is a rigorous maintenance schedule by blowing them out every 30 days. I have a Miller XMT 304 and I bought it with a shorted out board and I blow out all my machines regularly.

[youngdylan]

When I was working in a large fab shop We had 75 invertor power sources and have seen many shorted out boards due to grinding dust, even on the newer one that have sealed boards. The only thing I have seen work is a rigorous maintenance schedule by blowing them out every 30 days. I have a Miller XMT 304 and I bought it with a shorted out board and I blow out all my machines regularly.

I guess one litle particle on its own wouldn't be able to short anything, but as that particle became a layer of particles it would also become a CONDUCTING layers of particles ..hence the need to blow out

[Mainely,Bob]

I guess one litle particle on its own wouldn't be able to short anything, but as that particle became a layer of particles it would also become a CONDUCTING layers of particles ..hence the need to blow out

One must keep the magic smoke INSIDE the box,grasshopper.

[Bentiron1946]

What recommendations for preventing this happening has the units manufacture suggested? They surely have had this problem before. Back in my youth when I did some clean room design it would only take a particle less that .03 micron to ruin a printed circuit chip. We would have HEPA filters that were changed only every five years, the pre-filters every month. HEPA filters get more efficient the more particle they arrest. Those 3M house filters are pretty good for your house and may be all you need to provide clean air to you induction heater but the frame that holds them has to have a tight seal or the particles can sneak by the filter's cardboard frame. You can use a high density foam rubber gasket, it will help seal the gaps. I don't know how much cooling CFM your unit needs but if it is like some welders you could get by with a large squirrel cage fan and a 25"X25"X1" pleated 3M HEPA filter. That filter ought to be good for around 1,200CFM or you could do two of them and slow down the velocity of the air going through the filters, decrease the friction loss and increase the potential volume. Got all that? Now all you gotta do is build a nice plenum around you device so that you have a positive air flow to the rest of the room so no contaminated air get to your protected device. You need to run this fan all the time you grinding in the shop or working, anything that is throwing off particles that could fry your wonderful new machine. You could may be interlock it so when you turn on the shop lights the fan with the HEPA filters come on to keep a positive air flow on the machine. How would that be? :blink:

[youngdylan]

What recommendations for preventing this happening has the units manufacture suggested?

None that I'm aware of, thats for the induction heater, the Lincoln TIG and the Thermadyne plasma cutter.

The more I think about it the more I realise I've been skating on thin ice. I just had the TIG and plasma cutter under the bench thinking "that'll do". Also thinking about it, I did have a laptop that I take to the workshop go down (secondhand "IBM thinkpad" so we're supposedly talking quality here) and two cordless battery chargers (DeWalt and Makita)

When get a bigger workshop, a grinding room is a must

[Judson Yaggy]

I too work professionally in smaller spaces, 900 sq. ft. tops. It's either just me or me and one other guy in the next room. For all the disadvantages of a smaller shop it is quite easy to change out the air in the ENTIRE shop. Get a wall or roof mounted power vent, buy a big one. Every time you reach for a grinder, turn on the vent. It should be strong enough to suck out all the grinder stuff light enough to float into small openings (also strong enough to suck off your hat). Cover the electronics while grinding or locate upwind of the grinder/vent. Let it run for a little while after stopping. Another way to keep down the dust is to vacuum the floor with a HEPA rated vac every day/week/other. I've got no science to back up this claim but I suspect that feet can kick up as much left over grinder swaff as the original abrasive activity did. And never mind damaging the equipment, what about all those super fine particles getting into our lungs?

[pkrankow]

What recommendations for preventing this happening has the units manufacture suggested? They surely have had this problem before. Back in my youth when I did some clean room design it would only take a particle less that .03 micron to ruin a printed circuit chip. We would have HEPA filters that were changed only every five years, the pre-filters every month. HEPA filters get more efficient the more particle they arrest. Those 3M house filters are pretty good for your house and may be all you need to provide clean air to you induction heater but the frame that holds them has to have a tight seal or the particles can sneak by the filter's cardboard frame. You can use a high density foam rubber gasket, it will help seal the gaps. I don't know how much cooling CFM your unit needs but if it is like some welders you could get by with a large squirrel cage fan and a 25"X25"X1" pleated 3M HEPA filter. That filter ought to be good for around 1,200CFM or you could do two of them and slow down the velocity of the air going through the filters, decrease the friction loss and increase the potential volume. Got all that? Now all you gotta do is build a nice plenum around you device so that you have a positive air flow to the rest of the room so no contaminated air get to your protected device. You need to run this fan all the time you grinding in the shop or working, anything that is throwing off particles that could fry your wonderful new machine. You could may be interlock it so when you turn on the shop lights the fan with the HEPA filters come on to keep a positive air flow on the machine. How would that be?

Why not buy an old air handler (the inside part of of a heat pump system, looks like a furnace) or a furnace and just take all the guts but the filter (may be an attachment) and blower out, then put the thing blowing under a converted work bench so there is clean air and a low dust environment under there. All the hard part of that system done, just build a plenum and duct.

I bet you can get an old unit cheap off a HVAC shop after telling them what you need to do.

Phil

[youngdylan]

OK so whilst making a temporary shelter with the cardboard box it came in, I thought this might work as a practical solution.

I'll make a similar box out of steel so it's only open to ingress at the front. About 4 inches of clearance at the back where the fan is and 1-2 inches around the sides/top/bottom. I'll then pack the gap between the heater and the box at the front where the air is drawn in with a suitable high flow filter material. I'll pull the power supply lead and water cooling pipes round the front as in the photo. I can then slide the unit in and out for easy maintenance/ regular blowing out etc, all I have to do is remove the packing at the front

My way of thinking is the heavy lifting of the cooling is done by the external water cooler unit (and the water pipes go ALL round the electronic gubbins inside the box). The air for the fan is drawn round past the top/ sides to get to the fan at the back so it might be more of a cooling action than just directly in through the fan.

I'll also run a bead of silcone around the edges/joins of the panels of the machine itself

I don't need to go overboard with some sub micron filter,, it's the particles of metal I'm most worried about. Any that do get past what ever filter material I use at the front will have to travel about 2 foot AND get drawn UP to get at the fan. Chances are they'll just drop down before they do. All this, combined with regular blowing out might keep the dreaded dust of death at bay.

I've only had the machine 2 days and already I can see it being utterly indespensable.