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titanspark76
06-11-2016, 03:43 PM
Going to build my 1st mortar rack. I ordered 20 tubes and will build (4) 5 tube racks. From searching around looks like there are plenty of ways to go, but was hoping to get feedback on my plan. I have access to some CAD software and modeled it up and made a cut list with material. Any suggestions?

titanspark76
06-11-2016, 04:14 PM
Right after I posted I decided I didn't like the spacing (is there a way to edit the original post?). Anyway ignore the 1st attachment

djsmurf
06-11-2016, 08:37 PM
Spacers are nice, however just seem to add weight to consumer racks. Supports are nice, do you plan to remove them for storage and transport? They will be nice racks any way you do them.

titanspark76
06-11-2016, 08:48 PM
Spacers are nice, however just seem to add weight to consumer racks. Supports are nice, do you plan to remove them for storage and transport? They will be nice racks any way you do them.

Thanks for the feedback. I think I'll take your advice and ditch the spacers. Probably will go with a 6 tube version as well and save a couple of the tubes for next year (then buy more and make a bigger rack) . Will be removing the supports for storage and may change it to 16" wide instead of 12" to be safe. BTW I don't have any tubes yet and the ones I ordered won't be here until just a few days before the 4th so I need to build the racks beforehand. Is 2.4" an accurate OD on these tubes or do they run on the high or low side?

displayfireworks1
06-11-2016, 09:05 PM
I converted your pdf. to a picture. Because we be some visual mofo's on pyrotalk forums. LOL
.
http://pyrotalk.com/wp-photos/wp-content/gallery/united-states-pennsylvania/rack-page-001-fb02cc7489476e797c35436d411fda58d8dcfc7c.jpg

PapaBearPyro
06-11-2016, 09:45 PM
Thanks for the feedback. I think I'll take your advice and ditch the spacers. Probably will go with a 6 tube version as well and save a couple of the tubes for next year (then buy more and make a bigger rack) . Will be removing the supports for storage and may change it to 16" wide instead of 12" to be safe. BTW I don't have any tubes yet and the ones I ordered won't be here until just a few days before the 4th so I need to build the racks beforehand. Is 2.4" an accurate OD on these tubes or do they run on the high or low side?
2.4 is perfect- 24 inch for a 10 tube base or 12 inches for a 5 tube base etc.- Plus just a smidge of wiggle room so no worries on 2.4. PBP
BTW-awesome plans-your racks will be sweet.

Npntransistor
06-12-2016, 10:50 AM
Suggestion, add a couple pieces of wood across the bottom of the stability supports so you can chuck on a couple bricks or rocks for good measure. But that's just me :D

Rick_In_Tampa
06-12-2016, 11:58 AM
Right after I posted I decided I didn't like the spacing (is there a way to edit the original post?). Anyway ignore the 1st attachment

Rack looks sweet! I'm with Npntransistor. The only suggestion I would make would be to add a strip of wood across the front and back at the base to connect the side supports. That would give you vastly improved stability front to back (preventing the thing from tipping over if a gust of wind comes along), and it would also give you 2 horizontal pieces of wood that you can use to stake the thing down into the ground for added security.

PGHBoom
06-12-2016, 07:49 PM
I place two 2-bolt conduit clamps on each side and pound a 1/2" rebar through them. They work quite well in the grass. But your design is good for hard flat surfaces with the opinions from others incorporated.
1080

Rick_In_Tampa
06-14-2016, 12:42 AM
I place two 2-bolt conduit clamps on each side and pound a 1/2" rebar through them. They work quite well in the grass. But your design is good for hard flat surfaces with the opinions from others incorporated.
1080

That is an excellent idea!! Good call.

titanspark76
06-14-2016, 08:31 AM
Like I mentioned before I decided to ditch the spacers and go with 6. I built them before I got the last couple replies about improving the stability. They seem pretty stable as is, but I won't chance a safety issue so will add an additional board with holes to include a spike like in the picture below or I will do the rebar method that was mentioned. Thanks to all that replied. While on the small side compared to most here every year I'm going a little bigger. This year I have around 100 canister shells, 15 500 gram cakes, a few fountains and 200 grams (with the obligatory parachutes for the kids). Also bought a cheap chinese firing system to experiment with. Next year would like to have around 100 tubes and a better firing system.


1084

chriskrc
06-14-2016, 04:56 PM
I place two 2-bolt conduit clamps on each side and pound a 1/2" rebar through them. They work quite well in the grass. But your design is good for hard flat surfaces with the opinions from others incorporated.
1080

Never thought of that, looking forward to seeing the finish product. Great job.

PGHBoom
06-22-2016, 09:32 PM
1103I made this rebar holder yesterday. 4" X 2'-0" long PVC pipe with one end cap, one adapter with screw plug, a standard handle and two pipe clamps. I can hold 30 1/2" dia rebar pieces X 2'-0" long. Any more and you will feel like you are in a worlds strongest man contest.

pyroboom
06-22-2016, 10:37 PM
I have a some comments on your design.

1) On the side bottom rail it appears it's 5" tall. I would only make it 3" tall. This way the shell sits above your bottom rail. Your bottom support is a 2x3 and is 1.5" tall. Your plug is 1.5" tall for a total of 3"

2) Your rack is lifted off the ground by 1.5" correct? I like it when racks sit on the ground. I know you have a 2x3 under your rack and the bottom rail adds vertical strength, but let gravity do it's thing and put the weight at the bottom.

3) You are adding 2 end supports with a lot of extra cuts, why not have just one base plate on the bottom about 17.5" long and about 12" wide? You are making extra cuts and wasting wood by having the angles. Yeah, it's looks pretty cool, but I don't think you need it.

Like this:




1104

titanspark76
06-22-2016, 11:03 PM
1) I thought the bottom rail OSB was supposed to give some protection in case of a shell failure and you wanted it to extend pass the shell.
2) I had actually built the racks prior to getting some advice to improve the stability. I changed the design on paper, but not actually modified yet. Leaning towards leaving as is as it seems very stable. I have a lot of scrap 2x2's laying around and will probably drive them down on each side to be extra safe.
3) lol. I was actually planning on doing exactly as you showed initially, but decided that it didn't look cool.
Here's the actual rack
1105