machining question / BIT

[HTRN]

That is a good idea, except grade 5 titanium is hugely expensive except from the place I get it.

Who said anything about titanium? Use perforated 304 stainless. It will be half the weight of solid sheet and vastly cheaper than titanium - a .048 thick sheet of SS with .125 holes, 4'x4' is $570 from McMaster and has a 40% open area.

[Precision]

In this video they are talking about arrow tests but you can see some results on the breaths of a helmet.

LINK

that part starts just after 40 minutes.

very nice on topic video

[Precision]

That is a good idea, except grade 5 titanium is hugely expensive except from the place I get it.

Who said anything about titanium? Use perforated 304 stainless. It will be half the weight of solid sheet and vastly cheaper than titanium - a .048 thick sheet of SS with .125 holes, 4'x4' is $570 from McMaster and has a 40% open area.

will look into that, thanks

[Precision]

That is a good idea, except grade 5 titanium is hugely expensive except from the place I get it.

Who said anything about titanium? Use perforated 304 stainless. It will be half the weight of solid sheet and vastly cheaper than titanium - a .048 thick sheet of SS with .125 holes, 4'x4' is $570 from McMaster and has a 40% open area.

https://www.tigertitanium.com/storek/Plate/6Al-4V

4 plates of 12x48" is $155 each so $620 total. It isn't vastly cheaper, but it is when you consider the time element of making the holes.

[Precision]

The other thing,
The stainless for a 12x12 section at .036" thickness is 1.47# without holes. Is .882# with the 40% hole option. The TI without any holes is .845#

This means there is zero weight advantage to using the perforated stainless.

I may buy some of the perf non-stainless to do testing with and compare to the same steel that is not perforated then I can extrapolate what should happen with the TI. So thanks for making that suggestion.

If I did the 40% holes in the titanium, it would be .507#, which is a significant reduction

[Combat Controller]

What tooling do you have? Would you be able to add Scandium Alloy or Aluminum?

[Precision]

What tooling do you have? Would you be able to add Scandium Alloy or Aluminum?

7071 aluminum is about the same strength (my very amateur research) as grade 2 TI, but it galls much easier and thus would wear out faster. Don't know anything about scandium alloys other than some smith revolvers used them.

As a reference grade 5 TI is +150% stronger than Grade 2 in all fronts and about 60-80% stronger than grade 4 TI. Which is why I am using 0.8mm Grade 5 where others use 1.0mm grade 4. 20% lighter and damn near the same protection. Provides less fatigue and less heat build up so you fight better, stronger and faster.

[Combat Controller]

Hmmm