ABS vs HIPS

[Brickybrickbrickson]

Ive seen that HIPS armour is much less expensive than ABS. I've only ever worked with ABS but not a whole lot.

1. Is this because HIPS is a worse material?
   
2. What are the pros and cons for both ABS and HIPS?
   
3. Is it worth investing in HIPS armour at all?
   

[Stroker]

It's not as sturdy and will not take a beating like abs will. I've seen this question I know 3 times today. Does this have anything to do with a biker scout helmet?

[Strider]

As Tim said, I wouldn't take my chances with hips armor for trooping. Who's using it for a biker scout helmet?

[Stroker]

I'm sure it's about CB's new five piece hips helmet. I've seen one it's nearly completely transparent. Yes it's that thin. Its more a decor piece than a trooping helmet. There other helmets out there ready to wear for a little extra money.

[Dart]

HIPS is:

- High Impact PolyStyrene

- more brittle than ABS

- has a lower melting point so it forms quicker and sharper than ABS

- is more prone to cracking or chipping than ABS

- a material used for the original ANH TK helmets

 

ABS is:

- Acrylonitrile Butadiene Styrene

- much more flexible than HIPS when shaped (and in general)

- has a higher melting point and a bit trickier to form and shape

- used in car bumpers, so it's durable

- more expensive than HIPS

[Pandatrooper]

Go for ABS all the way if possible. I can understand why some makers will use HIPS, it costs less and is more stretchy and forgiving. But it's not nearly as durable as ABS. Your shower stall in the bathroom? ABS. Your landline phone? ABS. Most electronics like computer monitor casings, etc.? ABS.

[bugdozer]

My armour is HIPS. What others have said is correct - it has no real flex to it and is somewhat brittle. However, there are positives to it.

It is naturally shinier than ABS from what I've seen, and despite occasionally scraping against walls, furniture and other abrasives while trooping, it seems not to scratch up as easily. I can't be sure, but I think it is slightly less dense and so will weigh less for equivalent thickness.

My helmet wasn't in any way translucent - I painted it because of needing to use filler, but it would have served fine in its natural state.

If you want to know what HIPS is like - it's what they make the salad trays in fridges out of, as far as I can tell.

[tk1234]

I assembled an ABS helmet kit; I didn't care for the medium at all. I then purchased a HIPS helmet kit. The parts are molded in halves, not as a bucket. I like this assembly method much better, but more than that, I like working with the HIPS. The thickness of the helmet pieces is perfect. HIPS cuts easy and fills and sands nicely. From my helmet experiences, I have no qualms about using HIPS for the body armor pieces. In fact, I'm going to search out the guy that sold me the HIPS helmet kit and order his armor kit next. I hear that his armor is just as accurate as his helmets. But he works in HIPS which does tend to scare off some people.

[Chef]

My armour is HIPS and it's been going for years with no ill effects... But then it is 3mm. I'm a complete dork in mine as I am sure any of the UKG chaps will confirm!

 

HIPS has more 'impact' resistance than ABS (the clue is in the name), but is far more prone to cracking under torsional load (flexing and twisting).

HIPS is also less likely to 'yellow' over time, unless you have the acrylic caps ABS, which is UV resistant.

 

Now Scout armour doesn't tend to come under much torsional stress, certainly a lot less than compared to TK armour, so doesn't tend to suffer the cracking that you get with a TK made out of the same material.

 

The only area that is likely to suffer is the belt, and then only if you keep flexing it to put it on and off (which shouldn't be necessary).

 

It isn't all that much cheaper than ABS, so people shouldn't really use that as a justification (3mm HIPS costs practically the same as 2mm ABS).

 

Helmets made in HIPS shouldn't be a problem... They don't suffer any stresses as a such, so you shouldn't be worried by this. Material thickness is always a factor with HIPS, so the thicker the better. I wouldn't trust anything less than 2mm in HIPS, 2.5mm or 3mm for preference, and that is purely because of the mechanical properties of it.

The thicker it is, the more resistance to torsional stress, therefore the less likely to crack.

If you can see through it... I would avoid it on principle, as that can't be good.

 

The reason a lot of people don't use it is because it is hygroscopic and absorbs water. So unless you have a drying facility, when it is formed the water boils in the plastic and 'pops' holes in the surface and ruins the sheet. HIPS doesn't do this.

Obviously, this isn't an issue for 'formed' stuff, because you are unlikely to try and heat it up this much again...

 

TK Lids were originally made out of HDPE, which is another beast again....

 

In short, thick HIPS is no better or worse than ABS. It's just 'different'. Certainly where Scouts are concerned. I would never use it for a TK which has to inherently have more 'flex' in the suit.