[universeplastic]

Make one yourself. If you can’t do it, just customize it.

[Mavigogun]

While there has been some tertiary conversation about the performance of HDPE when milled that I've participated in, the primary thrust of this thread relates to success with long tooling. The suggestion to experiment, as a general recommendation, is sound- it just isn't applicable as a first course of action for ME with these costly tools, Craig. From my perspective, our focus was in different directions, and comments aught to be regarded with that in mind. This isn't- or at least, shouldn't be -a contest of knowladge; I'm keen to hear about folks experience, then interrogate the details of that experience for revising my own understanding.

[metalmayhem]

you've mentioned cost a couple times in this thread . I'd suggest looking at hss , 2 reasons are cost and a new hss tends to have good sharp edges which is benficial for cutting plastics .
Deep pockets aren't uncommon and most if not all metals benefit from the use of carbide under the circumstances . Plastics on the other hand are perfectly fine to use hss on

[joeavaerage]

Hi,

From my perspective, our focus was in different directions, and comments aught to be regarded with that in mind.

I keep asking you..... have you ever tried milling HDPE? If not, I suggest an experiment....I have.... on any number of occasions and my experience is that HDPE is a poor candidate
for parts of good dimensional tolerance and can be damned hard to get a good surface finish because of its propensity to form strings rather than chips. If you had tried it yourself
you may well come to the same conclusion. Seems little point in paying big dollars for a tool unless you have some experience that suggests its going to work acceptably.

Craig

[Mavigogun]

@metalmayhem, HSS might be an option, but have been cautioned against it with the purposed 7" stick out on 3/4" diameter by folks claiming experience with such long tooling into HDPE. I'd be happy to forgo the expense if you are reporting otherwise.

[Mavigogun]

If you had tried it yourself you may well come to the same conclusion.

I understand that your efforts were rewarded with dissatisfaction. Other folks have surmounted the issues you've cautioned against, producing admirable results. I will scrutinize my results and tune operations until able to achieve what others have demonstrated. I'll report back whatever the case.

[metalmayhem]

@metalmayhem, HSS might be an option, but have been cautioned against it with the purposed 7" stick out on 3/4" diameter by folks claiming experience with such long tooling into HDPE. I'd be happy to forgo the expense if you are reporting otherwise.

As I mentioned - when it comes to metal there is a large benefit in using the rigidity of carbide especially when using long reach tools . A 3/4" hss is still a fairly beefy tool and the difference here is you'll be cutting butter vs the butter knife . A lot of general carbides will not have the edge that a decent hss will have . When it comes to corners and such it's important to not hit them too fast but that will be the same case with carbide as well with long series end mills . If you go with carbides be sure to get quality cutters that are going to have a good edge to them