Tig welding tips, questions, equipment, applications, instructions, techniques, tig welding machines, troubleshooting tig welding process
MFleet
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This is my functional restoration progress and hopefully it will help someone later. I'm a total noob to tig so I will add some of the learning hurdles on that realm as well.

I've wanted a tig machine for ~20 years and found this one for sale locally. It has been whipped like a rented mule and it probably was in rental circulation at some point. I was only able to do a brief inspection which makes this purchase a high risk. It was from a brick and mortar business however and they did perform some basic testing. It came with absolutely zero auxiliaries to run it.

The Machine:
Miller Syncrowave 250DX 06/07 year model. This has an integrated cooler or "coolant on demand"
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exnailpounder
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Welcome to the forum. I believe you can "call up" the arc times and hours on that machine. I had a Syncrowave 200 that I was able to do it on and my new machine does it as well. Might give you some insight as to what she was into. Check out your manual. Great welder but your electric bill is going rise :shock: . I got a new inverter because my electric was so high running a transformer machine but other than that it's a great machine.
Ifyoucantellmewhatthissaysiwillbuyyouabeer.
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exnailpounder wrote:Welcome to the forum. I believe you can "call up" the arc times and hours on that machine. I had a Syncrowave 200 that I was able to do it on and my new machine does it as well. Might give you some insight as to what she was into. Check out your manual. Great welder but your electric bill is going rise :shock: . I got a new inverter because my electric was so high running a transformer machine but other than that it's a great machine.
Yep. I don't have the manual in front of me to tell you how, but you can call up both the number of starts and total hours arc time on that machine.

Steve S
exnailpounder
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Otto Nobedder wrote:
exnailpounder wrote:Welcome to the forum. I believe you can "call up" the arc times and hours on that machine. I had a Syncrowave 200 that I was able to do it on and my new machine does it as well. Might give you some insight as to what she was into. Check out your manual. Great welder but your electric bill is going rise :shock: . I got a new inverter because my electric was so high running a transformer machine but other than that it's a great machine.
Yep. I don't have the manual in front of me to tell you how, but you can call up both the number of starts and total hours arc time on that machine.

Steve S
Steve I just can't believe that you don't know how to do it by memory. You must be gettin old :lol:
Ifyoucantellmewhatthissaysiwillbuyyouabeer.
MFleet
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exnailpounder wrote: your electric bill is going rise :shock: . I got a new inverter because my electric was so high running a transformer machine but other than that it's a great machine.
Oh, wow, what are you welding on over there buddy? We need to change your name to "Weldpounder" :shock: Believe me, I'm already drooling over the Dynasty 350 and 700. Want them and need them now but I need to sell the house and my favorite two limbs first. Thanks for the welcome!

This is the arc time:
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MFleet
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Initial inspection:
The existing power cable was too small. Added a 6ga power cable and nema 6-50 plug from the home store. Confirmed that the mains jumper links were set to 230V. It fired right up and the coolant pump was pulling a prime. Things are looking good so I proceeded to order all of the other items to run it.

Cleanup and arrival of necessary tig/stick items:
The spark gap was adjusted to .008 (do not do ANYTHING to clean these like I did). The coolant tank was washed out several times until the funk on the bottom released. The tank fittings were rusted and wasted. The current sensing coil behind the front water/gas panel was broken off. The pump assembly, filter, and line hardware was gunked up. Everything that touched coolant was dissasembled and cleaned. I also noticed that the coolant on/off relay was bypassed. It was wired to run constantly when the machine is turned on.

Spent some time cleaning the overspray off of the control panel too.
  • The list of items purchased:
    Tig torch and leather cover
    Pair of dinse connectors and torch water adapter
    Tig torch consumables and 2% lanthanated tungsten assortments to cover .040 through 1/8
    1/16 aluminum 4043 and steel ER70S-6 filler rod
    Ground clamp
    Stick welding electrode holder
    40ft of Welding cable
    Foot pedal
    Diamond wheel and mandrel for dremel (tungsten sharpening)
    6011 3/32 electrode for general purpose stick welding
    Argon owner gas cylinder
    Tig gloves
    Assorted stainless brushes for aluminum cleaning
    Repair kit for the rusted water tank fittings and a new front water connection panel
    Already had a gas flowmeter, gas hose, and welding hood/helmet
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MFleet
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What I didn't know about gas cylinders:
I had two 250 cu. ft. cylinders in my shop that I took to my local welding supply for exchange. I knew nothing about them as they were included with a different equipment purchase. I only knew that I wanted a big supply of argon.

I have shuttled the same smaller 125 cu. ft. customer owned cylinder for exchange with them for 10 years. This cylinder was given to me with my smaller mig machine and it was shiny new at that time. Never had a problem with this. I have always looked at them as being super simple exchanges like the little propane cylinders.

One of the 250 cylinders had raised lettering on the neck ring. The other neck ring had some grinding done to it and re-painted to hide the lettering. The manager started getting an attitude with me when he looked at them and maybe rightfully so. The guy working the cylinder dock was a little nicer. Through talking to both of them and doing more research when I got home, I realized that these can be considered stolen goods. Any raised lettering is a leased cylinder(owned by the welding business) or was at one time.

I ended up buying a 250 cylinder from them and now I know how to buy cylinders from individuals. I just purchased another 250 cylinder from an individual for $35 with a current test date and a clean neck ring. The LWS gladly exchanged it. I also know that an expired test date is a small fee if I find another clean one.

I guesstimate that 90% or better of the cylinders for sale locally are not owned by the seller knowingly or unknowingly. This includes the modified neck ring scams.

A leased cylinder is always an option. It just isn't for me unless I need a special mix for particular project.
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Sounds like you're in business, then! I use the 250DX at work all the time and do all the maintenance on them.

I wanted to add, sometimes one MUST clean the HF points for one reason or another, and there's a pretty reliable way to do it. I'll remove them entirely, chuck them in the drill press , and run them gently against a fine flat stone a few times, moving the stone between touches. This keeps the faces parallel when you re-mount them. Once their re-mounted and the gap set, I rinse them with electrical contact cleaner to eliminate any debris or fingerprints from the faces, and let them dry.

I rarely have to do this, but there's a lot of metal dust in our shop and it seems like it can get cooked into the points over time.

Steve S
exnailpounder
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MFleet wrote:What I didn't know about gas cylinders:
I had two 250 cu. ft. cylinders in my shop that I took to my local welding supply for exchange. I knew nothing about them as they were included with a different equipment purchase. I only knew that I wanted a big supply of argon.

I have shuttled the same smaller 125 cu. ft. customer owned cylinder for exchange with them for 10 years. This cylinder was given to me with my smaller mig machine and it was shiny new at that time. Never had a problem with this. I have always looked at them as being super simple exchanges like the little propane cylinders.

One of the 250 cylinders had raised lettering on the neck ring. The other neck ring had some grinding done to it and re-painted to hide the lettering. The manager started getting an attitude with me when he looked at them and maybe rightfully so. The guy working the cylinder dock was a little nicer. Through talking to both of them and doing more research when I got home, I realized that these can be considered stolen goods. Any raised lettering is a leased cylinder(owned by the welding business) or was at one time.

I ended up buying a 250 cylinder from them and now I know how to buy cylinders from individuals. I just purchased another 250 cylinder from an individual for $35 with a current test date and a clean neck ring. The LWS gladly exchanged it. I also know that an expired test date is a small fee if I find another clean one.

I guesstimate that 90% or better of the cylinders for sale locally are not owned by the seller knowingly or unknowingly. This includes the modified neck ring scams.

A leased cylinder is always an option. It just isn't for me unless I need a special mix for particular project.
Around here AirgASS will not exchange a competitor bottle no matter what. My NEW happy nice LWS will take anyone's bottle but you have to pay for a hydro even if it's still in hydro. There isn't really any advantage to owning a bottle other than you can always sell it and usually get all your money back as opposed to when your lease is up you have to re-lease and pay all over again but the lease is 7 years. My LWS did tell me that 300cf cylinders are not for sale and if you buy one, it is considered stolen property. Anything smaller can be owned. Whether that's true or not I am not sure but I was going to buy 4 300cfs full of helium from a farmer and I called my LWS to ask them if they would exchange them and they told me not to buy them. My owned bottles are documented through the LWS as they took my bottles as an exchange but have their stamp in the neck but I can keep them forever. The whole ground off neck stamp scam doesn't go over around here. There are very few plain necks out there and the welding stores know it.
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MFleet
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Otto Nobedder wrote:Sounds like you're in business, then! I use the 250DX at work all the time and do all the maintenance on them.

I wanted to add, sometimes one MUST clean the HF points for one reason or another, and there's a pretty reliable way to do it. I'll remove them entirely, chuck them in the drill press , and run them gently against a fine flat stone a few times, moving the stone between touches. This keeps the faces parallel when you re-mount them. Once their re-mounted and the gap set, I rinse them with electrical contact cleaner to eliminate any debris or fingerprints from the faces, and let them dry.

I rarely have to do this, but there's a lot of metal dust in our shop and it seems like it can get cooked into the points over time.

Steve S
I used 600 grit sandpaper between them while very lightly squeezing them together. I've also brushed the outside of them. Apparently this isn't recommended. Some much finer sandpaper like 1000 or finer may be ok according another post that I read somewhere.

I tested the hf and it it is doing strange things. No idea if the sandpaper caused part of the problem. After starting the machine cold, It has tiny arcs between the big steel mounting plate and the red insulator while triggering the hf. Once it warms up the hf will start arcing properly between the points. I have seen things like this elsewhere in life. Humidity soaked insulator, carbon arc tracking, high resistance from out of tolerance components. Just don't know yet. I put some printer paper in the points and and let it arc against it. This seemed to help.

You have a good point on the grinding dust. It has a way of getting into everything. For that reason, I try to do most of the grinding outside of the shop which isn't always practical. Thanks for the advice and I will try out your suggestions if they give me more problems.
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MFleet
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exnailpounder wrote:Around here AirgASS will not exchange a competitor bottle no matter what. My NEW happy nice LWS will take anyone's bottle but you have to pay for a hydro even if it's still in hydro. There isn't really any advantage to owning a bottle other than you can always sell it and usually get all your money back as opposed to when your lease is up you have to re-lease and pay all over again but the lease is 7 years. My LWS did tell me that 300cf cylinders are not for sale and if you buy one, it is considered stolen property. Anything smaller can be owned. Whether that's true or not I am not sure but I was going to buy 4 300cfs full of helium from a farmer and I called my LWS to ask them if they would exchange them and they told me not to buy them. My owned bottles are documented through the LWS as they took my bottles as an exchange but have their stamp in the neck but I can keep them forever. The whole ground off neck stamp scam doesn't go over around here. There are very few plain necks out there and the welding stores know it.
Good info!

I decided to own the cylinders for a few reasons. Mainly it is a value system of owning everything that I plan to keep around for more than a week. My local also requires monthly lease payments(no yearly available) adding to my paperwork. Once I'm confident in my skills, the gas consumption should go waaay down. Nothing wrong with leasing for most. Expect them to do a credit check.

I started giving a little more thought to purchasing from individuals after your post. There is such a variety of rules from one shop to another like you mentioned. The only way to know you have a sure thing is to physically carry it to the LWS and get their blessing on it. A phone call first could save you some trouble too. I also checked my checked my cylinder over very well for damage. Layed it over and looked underneath too.
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exnailpounder
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Owning is ok because if you want to sell a bottle, you can get your asking price. My lease was great as I paid the 7 years ($270) in advance so no monthly headache AND if I return it before 7 years, they pro-rate the cost and give me back some cash. I couldn't pass it up. You will definitely go through some gas getting started but it gets waaay better as you improve. Glad to see you getting her running again. Those hours aren't bad at all. Those machines are meant to last and it sounds like you have some electronics knowledge so you should be golden.
Ifyoucantellmewhatthissaysiwillbuyyouabeer.
MFleet
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exnailpounder wrote:Glad to see you getting her running again. Those hours aren't bad at all. Those machines are meant to last and it sounds like you have some electronics knowledge so you should be golden.
Yes sir, It was a careful choice. One of my friends was repairing inconel turbine blades with this model. That was three years ago? Not sure what they have now. Good enough for me! I do have some electronics skills. It is now one of those things that seems like I've forgotten way more than I know.

Material choices for tig practice????:
I have a couple of kitchen bags full of aluminum cans that I scrounged from my buddies house. I'm building an order sheet for the local specialty metals place. I only have 1/16 filler on hand and plenty of it so that plays a part in what I picked so far. I could possibly double that up for thicker or use mig wire for thinner stuff.

STEEL-HOT ROLLED FLAT BAR A36 (HOT ROLLED A36 FLAT BAR 0.125 X 1.000)
ALUMINUM FLAT BAR 6061T6 (ALUMINUM 6061T6 FLAT BAR 0.125 X 1.000)
STAINLESS SHEET 304 (STAINLESS 304 2B SHEET 0.078 (14Ga))

What do you guys think about ordering this?

Cooler problems:
The repairs were fairly simple after the parts arrived. Re-pinning the connector for the new current sensing coil was a pain without a proper pin tool. I'm getting a hlp 17 code and this point and that points a coolant temperature problem. I checked the value on the coolant thermistor and it was reading way low(should be ~30k ohm at room temp). I disconnected the cooler connector at the board and wired the pump relay to run constantly so I could check that.

Now, remember me mentioning that the pump was priming before the cleanup? Now it doesn't :( . It just spins.

My theory is that I cleaned the gunk out of the pump and this gunk was giving the vanes tolerances necessary to function on some level. I triple checked that the parts were correctly aligned and noticed tiny marks of wear and some damage to the vanes.

The good news is that I was able to try out the machine as a stick welder. I've read posts that this machine burns sticks with excellence. They were right. I almost forgot how enjoyable it was to just to go through some rods without the pressure to fix something in a hurry. My Bud stopped by later and I taught him how to run some beads while we were chatting over some beers.
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MFleet
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More cooler circuit problems and the fixes:

OEM pump repair parts and entire replacements are not available from Procon. You may be able to get a new assembly from Miller for $400 and it can't be rebuilt. I've purchased a rebuildable style Procon pump/motor for plan B. It is spec'd at 230v, 2.8A, 105 GPH, 55 psi.

The old CMP style pump motor cools itself with water. This seems to be the main reason for using a thermistor. A resistor was soldered on in place of the thermistor and it fixed the hlp 17 code. It is a 1W 30K ohm 1% metal film type. This will falsely report ambient temp regardless of conditions. The Hobbs switch detects flow and that will shut down the machine if there is a serious problem. I should also note that these Hobbs style switches are adjustable. I've read posts elsewhere that these are problematic with restrictive torches and people end up bypassing it. It makes sense to adjust the set screw counter clockwise a bit it first.
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Got everything hooked up with some hose, etc. from ACE hardware. Now the machine does not seem to recognize that it has a cooler installed. The priming procedure listed in the owners manual still does nothing up to this point :( I started probing the connector at the board with a multimeter and noticed that a light would come on between the stick/tig lights. The probe was on the current sensing coil leads when this happened. This is the water cooled torch detected light according to the technical manual.
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On a hunch I placed a cheap disk capacitor between the two sensing leads. It works! I've confirmed that it cycles on when striking an arc on AC & DC, then shuts after a period on arc idle. The CLr & FLo display during prime procedure tells us that there is a cooler present and correct return pressure is detected. A sweet system when/if it works and way less noise when not welding.
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The cost of repair parts so far is ~$200 and it could probably be done for half of that. I will clean all of this up and try to make it look factory. I'm thinking of fabing a "dog house" for the pump on the back of the machine.
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MFleet
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I'm totally thrilled with how everything is going! This is by far more enjoyable than any welding process I've worked with.

I welded up the two bags of cans together that I mentioned in an earlier post. Something that helped was adjusting the arc starting current to "1 (light/soft start)". I found this in the manual under "Selecting TIG Starting Characteristics Using Syncro-Start Technology". Otherwise it would normally try to destroy the can right off.

I started out with getting up to grind the tungsten. After that, the cheap dremel & diamond wheel setup stayed within reach on the table next to the work. As you can imagine, the tungsten was coated with aluminum more often than not :evil:. It did help ease the pain a bit.

I had two types of cans and I did successfully weld up several of the thinner material up to 23 amps without blowing holes in them. This is a pic of the thicker bottle shaped type at up to 33 amps. The only thing I have to show for an empty cylinder of argon :|.
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MFleet wrote: I had two types of cans and I did successfully weld up several of the thinner material up to 23 amps without blowing holes in them. This is a pic of the thicker bottle shaped type at up to 33 amps. The only thing I have to show for an empty cylinder of argon :|.
Nice weld, was this done in a rotator?
Richard
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MFleet
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LtBadd wrote:
MFleet wrote: I had two types of cans and I did successfully weld up several of the thinner material up to 23 amps without blowing holes in them. This is a pic of the thicker bottle shaped type at up to 33 amps. The only thing I have to show for an empty cylinder of argon :|.
Nice weld, was this done in a rotator?
Thanks and no positioner yet. The ole gray matter is working on one already ;)

This was done by manually re-positioning in the vise in three beads. I think it looks more convincing than my skills actually are. I was using a heavy manual pulse with the pedal. This allowed me some time to get the filler rod just right. Believe me, I'm still fumbling with it.
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Just recently had more problems with the HF points after it was working just fine for months. Maybe humidity has something to do with it? I had a hunch that a bigger gap behind the insulator/phenolic material would be a potential solution. It was a dim, orange arc behind the red material to chassis ground when the arc was dropping out. I did a points cleaning on a stone in the mill as suggested. It didn't solve the problem but may have helped. It seemed to smooth it out a bit as the blue arc looks more defined. There is a fore/aft comparison pic of the points. I did a thorough cleaning of the insulator with brushes and acetone to rule out a any carbon tracks.

There is a pic of the factory scorched material and the potential fix that seems to have solved the problem. It is a butchered, folded up, poly water jug behind the red material. I took care to not place it behind the nylon screws where the arcing seemed to be concentrated. Maybe I will make some bushings for the mount screws. 6 hrs arc time and no glitches so far.

I'm hoping that this machine is close to a done project. The water pump housing parts are cut out. Just need to tack it together and button her up. Maybe a fire extinguisher mount to finalize this :)
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From the charred look on the edges of the holes it looks indeed like it was arcing on the studs/bolts to the back plate.

I suspect if you get a plain sheet of 3/32 or 1/8" thick PTFE and cut that to size to fit as a secondary/sandwich layer between the red one and the steel backing plate it will probably be fixed for good.

The exposed metal ends of the bolts/studs close to the ground plate and a short air-gap is probably not enough to insulate it completely for the HF signal. Your solution of spacing out the plate works for now but if/when dirt or moisture gets behind the plate then it may start to arc out on you randomly again.

A really well insulating layer would prevent this and PTFE is one of the most resistant ones out there to arcing and mostly inert to reacting with other materials and it does not absorb any moisture.

Bye, Arno.
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Arno wrote:From the charred look on the edges of the holes it looks indeed like it was arcing on the studs/bolts to the back plate.

I suspect if you get a plain sheet of 3/32 or 1/8" thick PTFE and cut that to size to fit as a secondary/sandwich layer between the red one and the steel backing plate it will probably be fixed for good.

The exposed metal ends of the bolts/studs close to the ground plate and a short air-gap is probably not enough to insulate it completely for the HF signal. Your solution of spacing out the plate works for now but if/when dirt or moisture gets behind the plate then it may start to arc out on you randomly again.

A really well insulating layer would prevent this and PTFE is one of the most resistant ones out there to arcing and mostly inert to reacting with other materials and it does not absorb any moisture.

Bye, Arno.
The mounting screws for the aluminum blocks are all nylon like the two you can see on the plate. All good points on debris collecting and adding additional resistance material. I will put that on the to do list.

Thanks,
Jeff
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Ah! Didn't notice the bolts were nylon too. My bad!

Having said that.. Under high voltage (like the HF operates at) many insulators do start to deteriorate and actually can start surface layer conducting at some point helped along by contamination and material degradation. I suspect you're also seeing an aging problem of the insulating material itself.

Some reading material.. http://www.industrial-electronics.com/epemt_1f.html

The base insulating mounting block does seem fairly simple in shape, so it may be feasible to at some time to completely replace it (and the mounting screws with a new block of material. Dig up a machinist-friend to replicate the original shape if you want :mrgreen:

Keep up the good work! I like to see older machines brought back with a little TLC and perhaps some small improvements/upgrades with the technology and meterials we now have available.

Bye, Arno.
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I suspect that you are right and I've figured out what the red insulator is. The description below reads that it will convert to fecal matter in the humid coastal regions. I have a piece of teflon on the way.

"GPO-3 offers superior arc and track resistance. NEMA grade GPO-2 (red color) and GPO-3 (red color) Glass-Mat Reinforced Polyester - These grades are composed of random mat (non-woven) fiberglass reinforcement held together by a polyester resin binder. (Polyesters are versatile resins which handle much like epoxies. Of course, the basic resins are chemically different. It's their physical application forms which make them similar. Despite lower costs, the important disadvantages of polyesters, as compared with epoxies, is lower adhesion to most substrates, higher polymerization shrinkage, a greater tendency to crack during cure or in thermal shock and greater change of electrical properties in a humid environment). GPO-3 offers both arc and track resistance. (GPO-2 certifies to Mil-I-24768/5 GPO2 and GPO-3 certifies to Mil-I-24768/6 GPO3). "
Miller 350P w/Python
Miller Syncrowave 250DX - Beaterwave project
Hypertherm Powermax65
Hobby class lathe and milling machine
MFleet
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    Sat Dec 10, 2016 5:26 am
  • Location:
    Houston, Tx.

The machine has been working VERY well with the temporary fix in place. I finally machined the new insulator and spec'd it a little thicker. The ptfe has tested good so far and this should be the end all of the HF problems. Thanks for the suggestion, Arno!
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IMG_20171013_015340851[1].jpg (59.42 KiB) Viewed 3363 times
Miller 350P w/Python
Miller Syncrowave 250DX - Beaterwave project
Hypertherm Powermax65
Hobby class lathe and milling machine
User avatar
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    Mon Nov 04, 2013 7:51 am
  • Location:
    The Netherlands

Good to hear!

PTFE machines nice.. It tends to suck up a little to end mills and drills so thin stuff can be a little tricky to keep clamped down, but it's usually quite nice to work on. Cuts well.

It just looks like Santa Claus is in town when you're done and your machine is covered in what looks like a layer of fluffy snow :lol:

Bye, Arno.
Iceax
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    Fri Nov 29, 2019 10:43 am

Hi Nice repair of your tig cooler in the syncrowave
Where did you get your motor and pump I am crossing the help code as well !
Thanks
Charlie
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