difference between sinker edm and non sinker one?

[kamuto]

hello, I'm looking to buy my first wire edm and cant understand what is difference between sinker one and non sinker, I understand one part is being cut under the water while another is just under flow of water, but what does that change?

sorry, maybe I have called it wrong, I mean wire edm but there are 2 types, one where part is fully submerged under water and another where water is just flowing over, it. I'm not sure how they are actually called

 

[Donkey Hotey]

What do you plan to do with it?

 

[kamuto]

planing to cut about 10/15mm thick steel parts with it, parts themselves not really big ones. at least now that's the plan, could not find any proper explanation on the internet, just that if you cut on angle sinker is probably better, and btw, what could be theoretical cutting speed on that thickness material?

 

[Donkey Hotey]

The type of EDM you're talking about is a wire EDM.

Sinker EDMs use solid electrodes they feed into the material to bore holes or create shapes.

Completely different machines, even though they both use electrical discharge to remove the material.

 

[kamuto]

sorry, maybe I have called it wrong, I mean wire edm but there are 2 types, one where part is fully submerged under water and another where water is just flowing over, it. I'm not sure how they are actually called

 

[precisionmetal]

By all means: try to get a "submerged" machine.

 

[kamuto]

By all means: try to get a "submerged" machine.

but like what is actual difference? it's faster, more precise or what?

 

[SteveEx30]

For thin parts like that a non-submerged machine would be fine.

Definitely faster and hold tighter tolerances with a submersible machine, it will keep the part at a more constant temp and flush better.

But they also come with more issues if you are buying an older machine. Sealplates, door leaks etc.

 

[kamuto]

I found one robofill 380 series machine with 2000 hours total and I'm thinking would it do the job.. btw, what is the speed of those machines, I know edm is slow in general, but like how slow, 0.5mm minute in 10mm thickness? or thickness does not really matter for speed here?

 

[BajaFire]

I found one robofill 380 series machine with 2000 hours total and I'm thinking would it do the job.. btw, what is the speed of those machines, I know edm is slow in general, but like how slow, 0.5mm minute in 10mm thickness? or thickness does not really matter for speed here?

With wire EDM, thickness is almost everything regarding speed. I usually guess (very rough numbers here) about .100"/minute in roughly 1/2" thick steel. YMMV

 

[precisionmetal]

I know edm is slow in general, but like how slow, 0.5mm minute in 10mm thickness? or thickness does not really matter for speed here?

The "sweet spot" for maximum material cutting (typically called out in area -- e.g. 10 square inches/hour, etc.) is typically when the material is 1"-2" thick. Thicker than that, the sq-in/hr goes down. Thinner than that, I've found that the sq-in/hr also drops. On relatively thin materials, I've typically had the best luck flusing from the top side and using suction on the bottom nozzle.

Of course wire size can have a huge effect on cutting speed as well, and wire size will typically just be dictated by the smallest "inside feature" (inside radius).

PM

 

[machinistrrt]

the sinker has a loop for the fishing line <G>

 

[kamuto]

The "sweet spot" for maximum material cutting (typically called out in area -- e.g. 10 square inches/hour, etc.) is typically when the material is 1"-2" thick. Thicker than that, the sq-in/hr goes down. Thinner than that, I've found that the sq-in/hr also drops. On relatively thin materials, I've typically had the best luck flusing from the top side and using suction on the bottom nozzle.

Of course wire size can have a huge effect on cutting speed as well, and wire size will typically just be dictated by the smallest "inside feature" (inside radius).

PM

ok, now I understand at least something, as I understand wire edm requires powefull air compressor too?

 

[kamuto]

the sinker has a loop for the fishing line <G>

that do you mean, I'm newbie in that...

 

[precisionmetal]

ok, now I understand at least something, as I understand wire edm requires powefull air compressor too?

No. Or I should say: "no, for the Agie 170HSS that I had for many years". I ran that machine with nothing but a ¾hp dental compressor.

PM

 

[machinistrrt]

that do you mean, I'm newbie in that...

No, just a play on words

 

[michael.guzzi]

I found one robofill 380 series machine with 2000 hours total and I'm thinking would it do the job.. btw, what is the speed of those machines, I know edm is slow in general, but like how slow, 0.5mm minute in 10mm thickness? or thickness does not really matter for speed here?

My machines can do about 4mm/min in 10mm steel, perfect flushing, submerged cutting. Will be similar for all steel alloys under the same conditions, but can go much slower if you can't put the flushing cups right against the part or if the machine isn't submerged. Can absolutely go down to that 0.5mm/min.

If you are a complete novice to wire EDM, make sure whatever machine you get comes with support and if possible a warranty that it is in good working order, these can be expensive machines to repair regardless of brand.

Also, low cutting hours isn't a guarantee that the machine is in 100% working order. An AGIE Progress V4 I used to run had only about 8000 hrs despite being nearly 20 years old, that's because it spent the rest of the time out of comission for the most absurd failures I've ever seen. It was ridiculous, and last I heard, it's out of comission again, failed HDD this time...

 

[Don Davis 87]

ok, now I understand at least something, as I understand wire edm requires powefull air compressor too?

No they actually use very little air volume, things like brakes and wire cutters are about all the air is used for.