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Posted

My old tubes finally gave up. Where can i get some 4" HDPE tubes on the cheap?

 

I already know about skylighter and they are over priced.

 

 

Thanks

Posted
Don't know what you consider cheap, but Pyro Direct has 4 inch HDPE for $7.50, racks and case prices available.
Posted
I wouldn't get fiberglass, but if you want to, 4" morters for 6.38 here.
Posted

I've always really liked Kastner. http://www.kastnerhdpemortars.com/

 

Shipping on these things can get expensive. For one or two any place will do, but if you ever look into getting a decent supply, geographics will play a role.

Posted
I'll vouch for PyroDirect and USfireworks.biz, they're both good to do business with; I do know both of the owners from different pyro clubs, so I am a little biased. Personally, I probably would go for fiberglass if I needed mortars right now because of the price. Most of my guns are HDPE, but the few glass ones I have are still in great shape.
  • 4 weeks later...
Posted
If you want fiberglass both Lynch and Waynes world have great prices.
  • 2 weeks later...
Posted
try a reputable building supply yard (not home depot). it is used in the construction trade.
  • 3 weeks later...
Posted

What are the advantages / disadvantages of HDPE vs Fiberglass?

 

It would seem like: (please correct if I am wrong or add if I forgot)

 

HDPE advantages:

more durable will not crack or chip if dropped on the end

 

HDPE disadvantages

heavier, more fatigee in setting up, moving or transporting.

 

 

Fiberglass advantages:

Currently cheaper than HDPE

Stronger (I do believe the burst pressure is higher in fiberglass than HDPE, but I might be wrong)

Light weight easy to move and carry

 

Fiberglass disavantages:

can chip or crack

can wear and give you nasty splinters

 

 

Posted (edited)

Some people will say fiberglass mortartubes cracks easier (than HDPE), but that really depends on the wall thickness and how the endplugs are applied by the manufacturer. I know stories of endplugs in fiberglas tubes made of gypsum, when buyers wants the best price, chinese factories makes the mortartubes in the cheapest way.

I disagree that hdpe is better, a good fiberglass mortartube will last very long.

Edited by FREAKYDUTCHMEN
Posted (edited)

Some people will say fiberglass mortartubes cracks easier (than HDPE), but that really depends on the wall thickness and how the endplugs are applied by the manufacturer. I know stories of endplugs in fiberglas tubes made of gypsum, when buyers wants the best price, chinese factories makes the mortartubes in the cheapest way.

I disagree that hdpe is better, a good fiberglass mortartube will last very long.

 

I agree with FREAKYDUTCHMEN. From what I've experienced, the fiberglass (if well made) are much stronger. They are lighter and if handled (reasonably) properly will not crack or chip. For splinters, you could wrap the mortar with foil tape or something, but I've never had a problem.

When shooting commercial shows, for mines we ONLY use fiberglass. The HDPE mortars were splitting and having the plugs blown out as they weren't strong enough.

Edited by Bonny
Posted
I'm sure it matters on the quality, but in my experience fiberglass is a little less resilient to repeated firing. In club shoot situations where the same guns are being reloaded over and over, fiberglass seems to fail a little faster. The walls seem to be thinner, so maybe they just heat up faster.
Posted

fiberglass seems to fail a little faster. The walls seem to be thinner, so maybe they just heat up faster.

 

Yea probably because they prefer cheaper tubes above good ones.

Posted
if your really worried about having the best mortars get some THICK walled HDPE and make your mortars for a couple of my guns I have thick as HDPE and I don't see them expiring
Posted
Fiberglass is a "tough" material, in the engineering sense - it's not brittle and cracks don't propagate. But it's inelastic, so every time you shoot it does some increment of damage to the composite, and eventually it will fail and shred. HDPE is both tough and elastic, so the repeated stretching from internal pressure doesn't degrade it much. However, this will work the end plugs loose over time, and a significant overload may pop them out. Metal compression fittings (hose clamps) around the plugged end help prevent that.
Posted

Fiberglass is a "tough" material, in the engineering sense - it's not brittle and cracks don't propagate. But it's inelastic, so every time you shoot it does some increment of damage to the composite, and eventually it will fail and shred. HDPE is both tough and elastic, so the repeated stretching from internal pressure doesn't degrade it much. However, this will work the end plugs loose over time, and a significant overload may pop them out. Metal compression fittings (hose clamps) around the plugged end help prevent that.

 

 

HDPE mortars are also prone to warping over time...becoming a bit oval. I've fired 6" shells where we had to push them in HARD due to warped guns.

Posted
I've heard that primarily happens when they're kept on their sides instead of standing up, especially when in direct sunlight. The commercial guns I've used in shows are kept in a covered building, and generally stored standing up in racks. I've never seen a single one warped.
Posted

I've heard that primarily happens when they're kept on their sides instead of standing up, especially when in direct sunlight. The commercial guns I've used in shows are kept in a covered building, and generally stored standing up in racks. I've never seen a single one warped.

 

Makes sense. They are commercial guns, but they are mostly stored on their sides. The buildings are covered though.

Storage methods also depend on the size of the operation, when storing large numbers of racks, space WILL become an issue, and standing up is not an efficient method of storage. I've only ever encountered warped guns on one show...but it does happen.

Posted

We store our guns in semi trailers on their sides, occasionally the gun will warp but that is due to "sloughing" due to firing the gun in a show. There have been shows that the ambient air temp is close to 100° F and then the show is fired bringing the temp of the HDPE up to a point where the material starts to reach its relaxed state which in some cases is oval, others it bananas though one can hardly see that in the short lengths we use.

 

In the trailer, even in the heat of summer, the guns just dont get hot enough to warp without the addition of the heat from fire.

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