To prevent grow tent from bowing in due to negative pressure

[SgtKiLLx]

If I can't find a design on the net (ought to be pretty easy to find on the various 3-D forums my nephew belongs to)
I'll just have my 14-year-old nephew do it with his setup when he has free evening to do it. Knowing him he can do a quick design in 20 minutes that will he can make and adjust if needed. It does not need to be anything but a basic design for me.
He has one of those Anet knock-off kits off of eBay that I assembled for a couple of years ago and he can design simple stuff like that pretty quickly.
Heck, just make a model, scan it, then make it, is what he'll likely do. That would even be quicker than a down-and-dirty quick design.
I bought his last spool so he owes me.

Cool. All ya gotta know is diameter of your poles.

 

[Elvin]

Cool. All ya gotta know is diameter of your poles.

He's got one of those homemade 3-D scanners ( it's one of those Kinect/X-box DIYs) so he'll just mock-up one then scan it, clean it up, then make it.
That usually is the quickest but since it is simple he could probably just make it on the laptop likely just as quick (as making the mock-up) but won't be as fun.
It will give him something to play with either way.

 

[SgtKiLLx]

He's got one of those homemade 3-D scanners so he'll just mock-up one then scan it, clean it up, then make it.
That usually is the quickest but since it is simple he could probably just make it on the laptop likely just as quick (as making the mock-up) but won't be as fun.
It will give him something to play with either way.

Sure. Wish you all the best.

 

[Elvin]

This is what his DIY scanner is

Not as good as an expensive one (he uses a homemade turntable with his) but better than those eBay cheapies.

 

[SgtKiLLx]

This is what his DIY scanner is

Not as good as an expensive one (he uses a homemade turntable with his) but better than those eBay cheapies.

Yeah I've seen that. Not a cheap setup. Using Skanect.

 

[Elvin]

That looks very nice.
If my nephew is done with the latest modification of his printer, I'll send it to him.
Kids his age love to modify these kits, which is why he wasn't given a plug and play, so half the time the thing is printing yet another doohicky some other kid has made (and posted the file of) and he wants to add to his printer or scanner or something that really does not need a new version of whatever he thinks he needs.
Anyway, school has started so I'm sure he is looking for something to do instead of his homework.
Thank you for your neat brace once again. He really will love to make it just because it actually will be useful to me.

 

[TorturedSoul]

Is negative pressure needed for carbon filters or something?

Technically, no. However, grow tents seem to range from okay to waste of money, in terms of quality. And I doubt any of them are completely airtight (not counting the vents and cord ports, obviously). Although I've never plugged those and spent the night inside one to see whether I suffocated .

What is the purpose of negative pressure?

Peace of mind and/or safety where odor control is required. If a grow tent is "leaky," running a slight negative pressure ensures that any pinholes/etc. will allow fresh air to enter, not odor to leave (via an untreated air path). Slight, because that's all that should be needed. If it looks like a two-liter soda bottle after you drink all the pop, pour in a cup or two of hot water, reseal, and chuck it into the freezer for a couple of hours, well, that's a bit much.

 

[Elvin]

Technically, no. However, grow tents seem to range from okay to waste of money, in terms of quality. And I doubt any of them are completely airtight (not counting the vents and cord ports, obviously). Although I've never plugged those and spent the night inside one to see whether I suffocated .



Peace of mind and/or safety where odor control is required. If a grow tent is "leaky," running a slight negative pressure ensures that any pinholes/etc. will allow fresh air to enter, not odor to leave (via an untreated air path). Slight, because that's all that should be needed. If it looks like a two-liter soda bottle after you drink all the pop, pour in a cup or two of hot water, reseal, and chuck it into the freezer for a couple of hours, well, that's a bit much.

I "tried" to use a carbon filter years ago but it just restricted the airflow to the point where my crappy old fans had no chance of cooling the tent.
It did make a nice little table though.
I realized that living on an acre means my neighbors are not going to smell anything so I don't worry about that filter.
That bracket will be used (maybe) for a clone tent that is just going to be scabbed together with conduit, old poles, plastic, and a corner of a room (two of the sides). It won't matter if there are huge light leaks, little alone pinholes.

 

[TorturedSoul]

They're definitely a restriction; at least the ones that are worth using are. And there are a lot of cheap axial (same type of design as the old-fashioned box type window fans) fans being advertised/sold as grow space exhaust fans when (a) they're pieces of sh!t and (b) those things aren't designed to work against any kind of restriction. Centrifugal fans are the proper type for this application. They're intended to move air when there's a restriction, filter, long duct run, etc. That's why they're used in central HVAC systems.

I'd assumed that you lived on a larger piece of property, lol, like many acres. Years ago, I rented a broken down 150+ year old farmhouse. Bad water, very questionable electrics, old undersized forced air furnace. Plus, there was no natural gas service in the area, so I had to keep paying someone to deliver propane. Which, I suppose, worked out to be somewhat cheaper than putting braziers in each room. wadding up piles of cash in each, and setting the piles on fire in order to heat the house - but it didn't really seem cheaper at the time. There was a much older furnace in the basement, too, that wasn't a forced-air type. Spider, octopus, something like that. Had a separate duct for each room. I was told it was a coal-burner, but never did more than glance at it. Landlady's daughter asked me to never, ever use the thing. I never met the landlady (95-year old woman living far out of state), and only saw her daughter the one time when she met us at the house to give us the keys. My kind of rental . Property was 49.75 acres. Tiny little yard, big woodsy hill, and across the road was the other 45 acres. That had long ago reverted to woods, but there was a year-round creek and a little hidden pond. With that, the house could have been a leaky tent and I'd have still wanted to live there.

But the old lady decided she didn't like living there shortly after we signed the lease. So when it was up (year), we moved. I should have had my arse kicked for that. Really should have looked at her and said, "Well, I guess I'll see you around, then (or not)." That came later, anyway and now I'm living on a tiny little crappy 1/4-acre city lot. Immediate neighbors are pretty tolerant - I've been known to open the back door and shoot the occasional rabbit or squirrel . Even fired the twelve gauge "once or twice" and wasn't reported. But I'm not going to try growing cannabis in the back yard, and won't do so inside without a carbon filter. That's a... well... I'd have to worry a lot more about pissing the neighbors off, for one thing, heh.

Er... ramble ramble.

Hey, OP, I forgot to add this question to my other post: Are those bars suitable for attaching things like circulation fans to? Maybe a SCROG grid that would end up supporting a full-tent plant?

 

[SgtKiLLx]

They're definitely a restriction; at least the ones that are worth using are. And there are a lot of cheap axial (same type of design as the old-fashioned box type window fans) fans being advertised/sold as grow space exhaust fans when (a) they're pieces of sh!t and (b) those things aren't designed to work against any kind of restriction. Centrifugal fans are the proper type for this application. They're intended to move air when there's a restriction, filter, long duct run, etc. That's why they're used in central HVAC systems.

I'd assumed that you lived on a larger piece of property, lol, like many acres. Years ago, I rented a broken down 150+ year old farmhouse. Bad water, very questionable electrics, old undersized forced air furnace. Plus, there was no natural gas service in the area, so I had to keep paying someone to deliver propane. Which, I suppose, worked out to be somewhat cheaper than putting braziers in each room. wadding up piles of cash in each, and setting the piles on fire in order to heat the house - but it didn't really seem cheaper at the time. There was a much older furnace in the basement, too, that wasn't a forced-air type. Spider, octopus, something like that. Had a separate duct for each room. I was told it was a coal-burner, but never did more than glance at it. Landlady's daughter asked me to never, ever use the thing. I never met the landlady (95-year old woman living far out of state), and only saw her daughter the one time when she met us at the house to give us the keys. My kind of rental . Property was 49.75 acres. Tiny little yard, big woodsy hill, and across the road was the other 45 acres. That had long ago reverted to woods, but there was a year-round creek and a little hidden pond. With that, the house could have been a leaky tent and I'd have still wanted to live there.

But the old lady decided she didn't like living there shortly after we signed the lease. So when it was up (year), we moved. I should have had my arse kicked for that. Really should have looked at her and said, "Well, I guess I'll see you around, then (or not)." That came later, anyway and now I'm living on a tiny little crappy 1/4-acre city lot. Immediate neighbors are pretty tolerant - I've been known to open the back door and shoot the occasional rabbit or squirrel . Even fired the twelve gauge "once or twice" and wasn't reported. But I'm not going to try growing cannabis in the back yard, and won't do so inside without a carbon filter. That's a... well... I'd have to worry a lot more about pissing the neighbors off, for one thing, heh.

Er... ramble ramble.

Hey, OP, I forgot to add this question to my other post: Are those bars suitable for attaching things like circulation fans to? Maybe a SCROG grid that would end up supporting a full-tent plant?

The braces are tough yes. PVC snapped into them ., They can hold some weight yes.

 

[SgtKiLLx]

For those of you who are following this thread, and own a 3d printer/have access to one, The PVC snaps , in sizes ,16, 19, and 22mm pole, are available on Thingiverse ,

 

[SgtKiLLx]

Updated and evolved once again. 16 & 22 mm available. 18mm upon request. For 3/4" pvc

 

[Emilya Green]

Very nice! We should have thought of that in the beginning!

 

[SgtKiLLx]

Very nice! We should have thought of that in the beginning!

Yeahhh I know. Wish someone woulda said something along time ago

 

[SgtKiLLx]

Very nice! We should have thought of that in the beginning!

Check it out. I asked him to send me some pictures. Photos to come soon

 

[SgtKiLLx]

@Emilya ,

 

[Emilya Green]

@Emilya ,

Very nice! They are beautiful. If I still used grow tents I would have 4 of these in each one!

 

[SgtKiLLx]

Very nice! They are beautiful. If I still used grow tents I would have 4 of these in each one!

Yeah I know. Just thought I'd show ya considering it was your idea originally, and how it's evolved since.

 

[SgtKiLLx]

@Emilya , I think ive finished with the design. I even decided to put it on Etsy. tell me what you think

 

[Emilya Green]

looks perfect! Market those things... surely there are people who want this, but just don't realize yet why they want it.