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Brother HS-300 on the way

Talk about a labor of love...jeeze
If I could do it over, I would have skipped on the brother and got a slightly newer aggie/gf with auto threading, chiller etc. I had my eyes on one that came in from 3M, talked to the guy that ran it, he was holding microns. It was crated up and ready for me - I had just bought the brother, and asked them to halt the shipment and swap with the robofil 1020 instead.. it had already shipped so I let it ride. Whoops :)
If I could do it over, I would have skipped on the brother and got a slightly newer aggie/gf with auto threading, chiller etc. I had my eyes on one that came in from 3M, talked to the guy that ran it, he was holding microns. It was crated up and ready for me - I had just bought the brother, and asked them to halt the shipment and swap with the robofil 1020 instead.. it had already shipped so I let it ride. Whoops :)
That's the way it works sometimes....maybe you can get some money out of it now with all the work.
That's the way it works sometimes....maybe you can get some money out of it now with all the work.
It's a great starter wire, and once the chiller is sorted out I think I can get some decent production out of it. I do want to improve the center/edge finding capabilities - I have not checked or adjusted anything in regards to the controller boards/pots yet, so maybe some improvement can be made.

I have the chiller temp wired up for now, and proper wires/terminals coming tomorrow. I am not confident the little pump in there will like being very far away from my tank, but I will give it a shot.. perhaps two of them pumping will be able to pull it off.

I've got a third option lined up, same model but wheeled version as I mentioned before, it has the same pump in it as my wire edm circulator pump so I think it would be a better candidate. Looks like new as well, problem is freight from CA is $$. We'll see!
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I tried to wire up the 2nd unit and the terminal strip dissolved in my hand from being soaked in caustic oils or something idk... so that's a parts unit for now!

Now for the good news - It's NOT pretty, but the first chiller did eventually pump the water 10ft both ways, I ended up having to connect the in/out lines I dropped in my clean tank and bleed the system that way, otherwise it was just overflowing my tank and not sucking anything back (air). Once the air was out, I disconnected the ends of the hoses that I had joined, while they were under water.. and that did the trick, no air in the lines and the pump would work.

(Also found two tarantulas under my water tank, from me opening up around the doors to run hoses, they got in, apparently is migration season).

Anywho, I set the unit to 20c and.... I GOT COLD WATER!
(It will let me go down to 5c but that's a bit nuts)

I'm letting it circulate now to resin out the tap water I added.. nice and cold on the sides of the tank!

I'm anxious to see how much of a difference this makes and if it can keep up! The factory offered (briefly) a RKS400, this is the RKS750 - so hopefully it'll be ok with my heavy usage.. Somewhere I posted a comparison chart.

I'll take the win for now - going to sit for a bit, I am wiped out and soaked!

The setup is basically all sitting on 5 gallon pals so I need to do a better job tomorrow and make a nema 3r enclosure.

Just ordered a foot valve, that should make priming easier next time.. also I was going to circulate cleaner though the chiller before I used it, but forgot - hopefully my water don't start stinking.


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I almost took a photo before I threw them out, my wife thinks it was a wolf spider, so I may be wrong 🙃

Heading back to work shortly..
Cut the wire and did a sanity check, says I'm out.00118 on both axis from where I was when I shut it off last night.. I'm doing my test square and will see what it says. First time with the chiller on, tank is staying cold so far. I dropped my wire speed to 3, will take a look at the spool and see how its coming out when it stops (or breaks)

Much less leaking when cold btw (well in some places still leaks to the gutter bad, from the split, but if not for that would be pretty good)

Just cut my test square, I am going to have to increase my offset for the 1st burn, I had nothing left to clean up... so I'm going to have to walk it out until it cleans up so I can check my position properly.. yet my pin don't fit. Interesting. I feel like I almost have to start over with my values now that the water is cold.. good problem I guess.. I will need to do some more testing before I commit the part. I suspect I will need to lower my power levels, the water is cold now and it's cutting better, thus over cutting?

My test square math did not add up so I'm cutting another one with a larger offset, power did end up remaining the same in the end. Water is staying ice cold!.. for some reason it seems I'm cutting tenths more in one axis than another and it's throwing off my math, roughed at 850 this time and cleaning up at 750 pass atm, 700 to follow if needed. .498 pin fits. I keep skimming but it's not hitting all 4 sides equally.

Oh boy. I might just have to get in dialed in under a thou and run it.

Finally got it to repeat with in .0002 - no idea how other than moving it around for a few hours I guess finally got it up to 'temp' starting out at 850 rough and 650 skim.

Cutting pocket #3, will do #2 after I know we are good, its a tighter tolerance... so far so good. Was not able to go any faster, but was able to slow down my wire a little. (so far)
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I was with in .001 on the rough pass at 850, must be cutting wider colder? should have had .002 to clean up.. set my skim to 750 instead of 650 but its barely cutting anything.. going twice as fast though as I normally could (skim). Should have some results here soon. Everything is nice and cold and leaks are all going in the gutter. No wire breaks, jams or any errors, so far!

I'm off .00001 on a X+ feature. Finish is butter smooth, only one minor line, though other side was +.001 so I think I need to shift X .0005 and go to 650 instead of 750 offset... I'll try 700 to be safe.

I was not seeing much action at 25000 speed, went to 50000 then ultimately 75000 for skim, it was cleaning up between ~.0005-.001 of material.

Adjusted and about to try pocket #2, which has a critical Y, so cross your fingers for me.

PS kinda weird pulling out an ice cold slug.

I wonder if new fans would make this thing quieter, I have to use hearing protection the fans are so loud on the cabinet.
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All done!

All with in ~.0005-/+ on size and position, towards the end I was just skimming tenths and realized its 0230 and I just need to be done. (.001+/- is fine)
The last pocket took about 5 hrs.

No wire breaks, skim was 3-4x faster.
Cool water is awesome.
I think the lower contact coolant line is blocked, but not sure how to fix that with out taking the lower head off, maybe if I find the port I and jab a wire in it, idk - its not bothering anything now, but that's where the wire was breaking with hot water.
I need to adjust my wire offsets, 850 rough did not leave much for clean up, 750 skim did not take off much, even walked it out to 650 and it still did not do much.. I think it needs a bigger 'bite' to work right but not sure if that is accurate. I will try 900 and 650 on the next part.
I can use a lot less wire. 3 on rough, 2 on skim. was up to 4/5 on rough and 3 on skim.

I think I've finally found consistency on this machine.

Will see how tomorrow goes, got one more part ready for wire.

I did end up ordering the newer chiller I mentioned earlier, my jerry rigged one could blow any day and I need something reliable...that's my story and I'm sticking to it!

It looks mint, and has a bigger pump, on wheels and latest revision of that model.
I should have no problem wiring this directly to the option contactor in the water pump power box.
Question is if I dog house this outside or leave it inside and deal with the extra heat. It does have the remote on/off function (as do the ones I have now) so anything is possible.



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Glad you found some Consistency finally. I'd say it's well earned !

Hopefully a smoother road ahead!
Thanks, hopefully today goes as expected!

I just thought of something, I'm going to put an indicator on the table when I shut it off tonight and see if it is still at zero in the am. I suspect the table is moving slightly over night for some reason.

I'm also wondering if I e-stop before shutting down if that will lock brakes...
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After this part is done I'll need to pull the lower head and clear the passage for the lower brush coolant, not sure where it is, can't find it.. but it's plugged and I'm snapping a couple wires at that spot again.

Also I found the procedure for adjusting x/y backlash and edge x/y finding


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Edge find adjust


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I ordered a decade resistance box off amazon and will go through all the procedures to check and adjust for the tightest accuracy on x/y axis and edge finding possible on this old girl.. for now my method of cutting a 1/2" square inside of the pocket with in an easy to measure X/Y distances (.500, .750, etc) lets me dial in it a thou and I'm golden, occasionally its only off tenths and I leave it alone. Luckily the 1/2 square is just big enough for the end of my micrometer to slip down into and I can reach a nice flat X/Y edge depending on the pocket I'm at.

Also in case anyone was interested, I put a dial indicator on the rail and shut the machine off.. just closing the door moved it half a thou :/ I tapped it back to zero.. will see if it's still there in the am, but that tells me alot.
I need to do the same with it powered up and see if it holds position, you'd think it would throw an alarm in that case.
Thanks for documenting your journey with the Brother! I’m sometimes tempted to get one as a second, “bandsaw” machine, but I think you’re definitely giving me reasons to reconsider.