pogue1000 Posted December 10, 2010 Posted December 10, 2010 Made my first 6" shell for club shoot tomorrow but I dont have a mortar on hand to test the size.What is the ID of a 6" mortar, is it 6"? I plan on cutting some templates out of wood or cardboard. Thanks
Algenco Posted December 10, 2010 Posted December 10, 2010 2" DR11 ID-1.926 Wall- 0.2163" DR13 ID-2.961 Wall-0.2594" DR17 ID-3.949 Wall-0.2655" DR21 ID-4.843 Wall-0.2566" DR21 ID-5.970 Wall-o.3158" DR17 ID-7.570 Wall-0.507
pogue1000 Posted December 10, 2010 Author Posted December 10, 2010 2" DR11 ID-1.926 Wall- 0.2163" DR13 ID-2.961 Wall-0.2594" DR17 ID-3.949 Wall-0.2655" DR21 ID-4.843 Wall-0.2566" DR21 ID-5.970 Wall-o.3158" DR17 ID-7.570 Wall-0.507 Thanks! Its gonna be a cold one,, but last Heartland shoot of the year!
Algenco Posted December 10, 2010 Posted December 10, 2010 make certain your lift and leader is waterproof, may be a little wet also. I'm still debating whether to attend
pogue1000 Posted December 10, 2010 Author Posted December 10, 2010 I think it will turn out to be a good time. Mike has put a lot of hard work into it.You obviously have a little further drive, hope to see you there! make certain your lift and leader is waterproof, may be a little wet also. I'm still debating whether to attend
Seymour Posted December 11, 2010 Posted December 11, 2010 View PostAlgenco, on 10 December 2010 - 11:41 AM, said:2" DR11 ID-1.926 Wall- 0.2163" DR13 ID-2.961 Wall-0.2594" DR17 ID-3.949 Wall-0.2655" DR21 ID-4.843 Wall-0.2566" DR21 ID-5.970 Wall-o.3158" DR17 ID-7.570 Wall-0.507 I'm somewhat confused. Is this the spects for the mortars used at the heartland shoot? If they are what you guys consider "standard" sizes for mortars, then I'm working on a very different set of measurements. For me the size on the name of the shell, is the size of the ID of the mortar. Thus a 6" mortar is 6" ID, literally. The shell, while called 6" will be slightly less than 6" to fit in a 6" mortar. If I bought an 8" mortar, in all honesty, I'd feel ripped off if it ended up being 7.507" ID.
Algenco Posted December 11, 2010 Posted December 11, 2010 (edited) I'm somewhat confused. Is this the spects for the mortars used at the heartland shoot? If they are what you guys consider "standard" sizes for mortars, then I'm working on a very different set of measurements. For me the size on the name of the shell, is the size of the ID of the mortar. Thus a 6" mortar is 6" ID, literally. The shell, while called 6" will be slightly less than 6" to fit in a 6" mortar. If I bought an 8" mortar, in all honesty, I'd feel ripped off if it ended up being 7.507" ID. those are the standard demensions of HDPE pipe used as mortars 6" DR26 is 6.04" ID Edited December 11, 2010 by Algenco
Seymour Posted December 11, 2010 Posted December 11, 2010 those are the standard demensions of HDPE pipe used as mortars I challenge you to present a commercially made shell that is the exact diameter as advertised As I said, the shells are smaller than the size they are presented as, so that they fit in to the mortar, which as I understand is intended to be exactly the size the shell is sold as (though I know inexact mortars are used frequently). I would be quite worried if a 4" shell was quite literally 4"OD. I know that the commercial mortars I've used have been much more accurately sized than what seems to be the standard for you. What happens when you get an 8" shell that has an OD of 7.85", a very comfortable fit in a mortar with an 8" ID, but nothing would make it fit in a 7.507" mortar? I am aware that Chinese shells have a tenancy to be undersized, but I did not know that it was so extreme, or so reliable as to make using 7.507"ID mortars a valid option for firing "eight inch" shells.
Algenco Posted December 11, 2010 Posted December 11, 2010 As I said, the shells are smaller than the size they are presented as, so that they fit in to the mortar, which as I understand is intended to be exactly the size the shell is sold as (though I know inexact mortars are used frequently). I would be quite worried if a 4" shell was quite literally 4"OD. I know that the commercial mortars I've used have been much more accurately sized than what seems to be the standard for you. What happens when you get an 8" shell that has an OD of 7.85", a very comfortable fit in a mortar with an 8" ID, but nothing would make it fit in a 7.507" mortar? I am aware that Chinese shells have a tenancy to be undersized, but I did not know that it was so extreme, or so reliable as to make using 7.507"ID mortars a valid option for firing "eight inch" shells. That's wht a lot of people use fiberglass It doesn't create a problem for me., I don't build anything that I don't have a mortar tube to check it with. That list was posted by someone awhile back, I saved it since I was on the hunt for HDPE pipe.If I were after 6' I would go with the DR26 @6.05"
Algenco Posted December 11, 2010 Posted December 11, 2010 8" DR32.5 8.05" ID10" DR32.5 10.0512" DR32.5 11.95
Arthur Posted December 11, 2010 Posted December 11, 2010 A mortar should be close to, or exactly it's nominal size, a commercial shell should be slightly smaller than nominal to allow clearance in the tube for proper function. Commercial firework mortars are made to size of bore to suit fireworks, Commercial pipe or duct made from PE or HDPE may not be the best sizes for fireworks largely because it's designed to an OD. SOME pro fireworkers will use different size mortars for effect. I remember some commercial 6" shells put up to three different heights by design simply with the use of mortars of different lengths. Choice of mortar is part of the art of displaying fireworks.
Mumbles Posted December 11, 2010 Posted December 11, 2010 If you build canister shells, it's almost inevitable that you'll eventually run into a situation where you make a shell that doesn't fit into a particular mortar, or needs a little extra "suggestion" that it should get in the mortar. Fiberglass is usually fairly uniform, but does taper a bit toward the bottom from the way they're made. Mighty-mite HDPE mortars are the same way. As you've already seen, there are quite a few different standards to HDPE. If you go to an unfamiliar club, sometimes you run the chance of getting slightly undersized vs. slightly oversized mortars, or a mix. 4.95 vs 5.05 can make a difference in some cases. If they're offered, I've found steel and long HDPE guns to just about always be slightly oversized. This is primarily a problem with multibreak shells, though 5" and 6" can cut it pretty close on their own. If you put that much work into a shell, sometimes it's better to bring your own gun with you, or at least test fit before dark. For what it's worth, I've never seen a mortar undersized by as much as a half an inch. Even that 5" DR21 looks a bit off.
Recommended Posts