SFA

For our first pallet of garnet, Barton Abrasives provided both HPA & HPX garnet. Supposedly the HPX creates a higher quality cut. I took that to mean "smoother" and maybe "more consistent." After having gone through our first pallet of HPA (or, regular old garnet, I suppose), we're now onto using HPX. Well.... I gotta say, I'm not impressed at all. In fact, I'm running into problems.

With both garnets, I've had the following problem: raising the large hopper pressure in order to maintain constant garnet flow. My normal operating pressure is 50psi on the large hopper. Doing this also causes little piles of garnet to spill onto the slab as it's cutting. However, the location from which the garnet is spilling out differs based on which garnet I'm using.

With HPA, the garnet is spilling out of a nylon hose that points down (to the floor) & is near the actual water jet nozzle. I've found that if I lower the pressure on the large hopper anywhere below 50psi, I have garnet flow issues & the machine stops frequently due to no garnet flow. However, AT 50 psi is when all this spilling of garnet happens. So I don't really have a "happy" medium, I just have a functioning situation that wastes some garnet. I've discussed this with Park Industries & they claim that I should be able to find a happy medium. Well, I've started at 30psi before & just gradually gone up with the pressure whilst running a job in order to find a point where it'll quit getting garnet flow alarms (so I can start a job & just leave it until it finishes). Well, that happens at 50 psi.

With HPX, I've been getting even MORE garnet flow alarms. At first, I thought it might be because the hopper was pretty low. So I filled it with HPX to eliminate that possibility. But I reduced the pressure on the large hopper because it was full all the way & Park Industries said that raising the pressure is probably only necessary as the hopper gets really really low. Well, I did the same thing, & gradually raised the pressure. Now I'm at 45psi, but I'm still getting garnet spilling out like crazy. I did a garnet flow test & noticed that what was coming through the hose (that plugs into the water jet nozzle) was only 3/4 of the amount that it should be. I noticed that garnet was raining down from the weep hole on the bottom of the mini-hopper. So I did another flow test, in order to figure out where the stop was coming from. I plugged the weep hole with my finger while I checked out the hose. No garnet in the hose, yet garnet is building up at the weep hole. I pulled the hose out & garnet flowed freely through the 'gator bite' that the hose was plugged into. Looked at the hose, nothing plugged in the end of the hose. WHY ISN'T IT GOING THROUGH THE HOSE??? I mean obviously, SOME is coming through, or I wouldn't be filling up my measuring cup 3/4 of the normal amount. I did notice that some of the HPX garnet is sticking to the inside of my measuring cup (plastic that came with the machine). HPA didn't do that. Side note: I'm not getting any garnet coming out of that hose that is near the water jet nozzle & pointing down while using HPX.

I spoke with Park Industries at length about this & they're stumped too. The best guess I've got is that this "HPX high performance abrasive" is no good.

Anyone else have issues like this or any experience using HPX or any other "high performance" abrasive?

We use HPA exclusively through the Fusion.
We find that it produces less wear on consumable parts -- mixing chamber etc.
You use more but it is less expensive, so it is about a push.

The pressure on the external hopper is just to get the garnet to the little hopper in the machine.
One is set at 35 lbs the other machine is set at 50 lbs.
Check your flow setting on the little hopper in the machine, ours is set at about 5.5.

Could it be an issue with that valve?

Dave.Scott wrote: ↑

Thu Sep 14, 2017 2:34 pm

The pressure on the external hopper is just to get the garnet to the little hopper in the machine.
One is set at 35 lbs the other machine is set at 50 lbs.
Check your flow setting on the little hopper in the machine, ours is set at about 5.5.

Could it be an issue with that valve?
[

Our flow setting is at 7 on the mini-hopper. At 50psi & 7 for the flow setting, the mini-hopper is at about the 2 line regarding how full it is. Are both of your Fusions set at 5.5? Do you experience any overflowing or little piles of garnet on your slabs as it's jet cutting?

Not while it is cutting, sometimes the tube from the hopper gets clogged with wet garnet and then we will get a garnet leak.

Dave.Scott wrote: ↑

Fri Sep 15, 2017 8:09 am

Not while it is cutting, sometimes the tube from the hopper gets clogged with wet garnet and then we will get a garnet leak.
[

I've attached a picture of the piles the machine was leaving while using HPA. These piles are spilling out of the hose that's pointing down toward the slab near the water jet nozzle while it's cutting.

The HPX spilling out of the weep hole doesn't look like this, as it's far messier.

There is a diaphragm in the head, if there is a hope in it that could be the source of the garnet leak

Dave.Scott wrote: ↑

Fri Sep 15, 2017 9:32 am

There is a diaphragm in the head, if there is a hope in it that could be the source of the garnet leak
[

I'm having trouble figuring out what you mean by a diaphragm in the head. I even asked one of Park Industries installers in hopes that they'd just tell me what it was, but they weren't sure what I was referring to.

Bladder.

I was having this same issue with garnet coming out of the overflow tube and piling up on my slabs. Have you taken the time to pull your mini hopper apart as described in the fusion manual? On your weekly maintenance task 1.6 you are checking to ensure that your garnet flow is at roughly 100 cc per 30 seconds. It says if its under adjust your dial and check again. But if you keep having a consistent problem then try the advanced maintenance procedure and pull it apart clean out all the parts of the minihopper and check for any abnormalities. Another issue that park has mentioned when i was having a consistent garnet flow issue like you're describing was that the hose from the mini hopper to your mixing chamber over time will wear as you have a highly abrasive garnet running through it all all times and these little scratches that the garnet creates can catch a little of your garnet up in the tube. all it takes is one tiny flow problem for a second for it to plug you up and trip the alarm. The only other thing i can think of is that something minute got into your large hopper and has slowly been working its way through the system creating issues as it goes. i had this issue for about a month earlier this year and nothing was working so i just had to work around the alarms and constantly watch the machine as it ran waterjets until one day i pulled the tube off the mini hopper and a hair from the paint brush that park attached to my large hopper was wadded up in the top end of the tube. garnet was still able to flow past it but it cut my flow in half which triggered the alarms. as soon as the hair was removed and i stopped using the paint brush to push my garnet down into my large hopper the problems stopped. hope any of this may have been helpful. I'm always looking for input and knowledge from others out there running the fusion like i am.

Park ended up sending out a tech to see what was going on & help with a bunch of other unrelated issues as well. What the tech said the likely culprit of the little piles of garnet are caused by ended up being a possible combination of issues.

Due to the small size of our shop & the location in which the Fusion fit, the main hopper is at the right corner of the machine by the intensifier cabinet. This is surrounded by a wall on 2 sides. So the installers for the Fusion built a square tube structure that goes overhead from the hopper & back down into the junction where all the hoses go to the Fusion. That way people can walk freely between the hopper & the intensifier cabinet & not trip over hoses. Well, THIS causes a steep drop for the garnet. We'll get back to this.

An additional issue that I think might come with all Fusions is the fact that when your hopper gets a bit low on garnet, it takes more air pressure to have the same consistency as when it's full. OR, if that's not the case, then when it is full, higher pressure causes a lot of garnet to be pushed through until the level in the hopper goes down to a "better" level in which the pressure used can perform more consistently. I do realize this is likely not the case for those who might have less travel involved with their hopper-to-Fusion layout.

So, couple these two together, and what happens (depending on the level of garnet in the hopper) is this:

Full hopper: a lot of garnet is falling down that steep drop I mentioned more often. Causing inconsistent "pushes" of air to travel through the line, which causes sudden overflows to the mini-hopper.

Med hopper: a decent amount of garnet is falling down that steep drop, but not so frequent that it's annoying. Maybe 2 piles of garnet per job cut, about the size of a half-dollar.

Low hopper: the amount of garnet falling down that steep drop isn't enough to overflow the mini-hopper, but it still stays full, almost thanks to that steep drop.

Conclusion: The tech offered to re-route the garnet hose so it ran on the floor, instead of overhead. Reducing the travel greatly, thus likely allowing me to reduce the pressure. But, this would then cause a tripping hazard, as these hoses (there's way more than just the garnet hose traveling overhead on this square tube structure) aren't exactly like walking across an extension cord. I don't even know if they make one of those hose ramps big enough to cover these hoses. So, I chose to live with the issue instead of create a tripping hazard.

As for the nylon hose that goes from the mini-hopper to the nozzle wearing out, we only ran about 10 bags of the HPX through the machine & we just recently hit 250 hours. So I doubt it's that there was some huge amount of wear in the hose, but I changed it out anyway.