Parting thin parts

Spruewell · Feb 25, 2018

Making some parts in 1” 2025 T-351 Aluminum. They are only .035 thick with an .065 thickness around the outside and tend to want to dish while parting. Tried grinding .065 thick thin-bits to reach, but had trouble with them breaking. Ran an indexable .125 parting tool, but it was eating up too much material.

LKeithR · Feb 25, 2018

Spruewell said:
...Ran an indexable .125 parting tool, but it was eating up too much material...

Underbid the job did ya? Next time allow for a wee bit more material and you should be fine.

As an aside, when using insert type parting tools on thin material try the inserts with a slightly angled cutting edge. They'll
break out on the "part" side before cutting all the way through...

Stihl290 · Feb 25, 2018

Slitting blade on live tooling?

Stefan Gotteswinter on Instagram: “Had to machine .2mm thick washers out of Igus Iglidur J bearingplastic. Parting on the lathe did not work at all, no matter what I did to…”

Spruewell · Feb 25, 2018

Customer bought the material and had it shipped to my door, so that is not really much of a concern. Just may end up a couple parts short of filling the whole order. Originally expected to yield about 1500 parts from the material, but after running into these issues with the parting tool, it will be real close to hitting the 1000 part order.
Hadn’t thought of the slitting tool idea. I may try setting that up in my live tool holder and giving it a go. Hopefully it won’t add too much to cycle time.

Triaged · Feb 25, 2018

1mm wide parting insert with sharp edge. Iscar DGN 1002J. Haven't tried it on Aluminium but it works great on thin wall stainless

ISCAR Cutting Tools - Metal Working Tools - DGN/DGNM-J/JS/JT : 678 - DGN 12J

litlerob1 · Feb 25, 2018

Spruewell said:
Making some parts in 1” 2025 T-351 Aluminum. They are only .035 thick with an .065 thickness around the outside and tend to want to dish while parting. Tried grinding .065 thick thin-bits to reach, but had trouble with them breaking. Ran an indexable .125 parting tool, but it was eating up too much material.

I would give the thinbits another try, no reason why they would be "breaking" in 2025, I would grind them down to as thin as humanly possible, I have hand ground them down to about .015" thickness with relief behind the cutting edge. Sharp, Sharp, Sharp is the ticket IF you need to part them off. Drop the indexable tooling now-ish, it isn't sharp enough. I would figure out how to make the HSS thinbits work.

Saw would be okay, I have used smaller Endmills to part off stuff (.0312") turning C and running Endmill on X.

OTOH, if you have wire EDM---there you go.

R

Limy Sami · Feb 26, 2018

Something not mentioned so far is heat, parting off is quite a heavy cut, and IME - especially with plastics! with thin washers etc ''I think'' the heat naturally goes to the thinner part, causing distortion, .......I know on one Acetal job, @300ft / min it was a disaster,.......@ 100ft / min - perfect.

I'd also look to getting coolant in exactly the right spot, and make sure the tool is sharp sharp, has enough clearance so it doesn't rub, and of course a feed rate where it's actually cutting and bringing the heat off in the chip as opposed to rubbing.

robert123 · Feb 26, 2018

How deep is the part off?

Red James · Feb 26, 2018

If the indexable parting tool works, quit fighting, buy one stick of material, and finish the job.

Search

Largest Manufacturing Technology Community on the Web

Search

Parting thin parts

Spruewell

Hot Rolled

LKeithR

Stainless

Stihl290

Aluminum

Spruewell

Hot Rolled

Triaged

Aluminum

litlerob1

Diamond

Limy Sami

Diamond

robert123

Stainless

Red James

Stainless

Similar threads