Thread 2950757

my work threw out a "labconco 30 inch fumehood". they were rennovating and it was going in the dumpster and i figured i could use it for soldering, or putting my 3d printer in, or sandblasting.

well that was about a year and a half ago and it's just been sitting in my garage.
the problem is i don't have a benchtop to mount it to. it's 30"x30"x48". which conveniently fits perfectly through normal doors.
however if i put a normal sized table under it, it'll no longer fit through doors, which are like 80" tall.
I want to keep the footprint able to fit through a door.

So, my plan is to make some sort of short table with wheels on it that I can jack up when it's where I want it to stay.
I've got 3 ideas for how to do this and I'm hoping you guys could sanity check me on these.

>>2950757 (OP)
My basic plan is to weld up a 4 legged table out of square HSS. probably 16 gauge, 1.5"x1.5".
a lot of jack options seem to be around 20" or so. I'd figure I'd make it at the highest with a worktop at ~34"

my current best idea is to steal this guy's design. This is welding table with a hydraulic long-ram jack. This would be too tall, the jacks are like 24" minimum.
But I can use this same concept with an RV scissor jack to adjust the height (20" of range) and then pin the telescoping legs to stay there.
I think this is a pretty good idea. I don't know exactly how I'd mount the jack to it.
https://www.harborfreight.com/2-1-2-half-ton-trailer-stabilizer-jack-96406.html
for mounting the jack, I don't know if bar stock is sufficiently rigid. Maybe i'd need to drill holes in some square tubing and bolt the top and bottom of the jack to it.
I also don't know how much of a pain in the ass it'll be to do the telescoping legs. it seems simple enough but maybe there's a lot of slop, plus the weld beads inside the tube.
and i'd want to put like a plywood sheet on the top of it as a work surface. I don't really know how I'd attach this without bolting through into the tubing which I think will look like shit.

>>2950758
I have two other ideas which I don't think are as good.
One was to just make a square table and bolt trailer jacks to the side. i think this would look awful and you'd bang into the hand-spinners. plus you'd have to walk around over and over to adjust them all. annoying, but less work to build since you just bolt it to the side of the legs. there's also about 10" of height gain.

my first idea was to put scaffold leveling feet in the legs of the HSS. Then I'd mount casters to the bottom of these.
it would be really annoying to hand tighten each scaffold jack, and i think there would also be pretty bad rigidity because it's just sitting on top of the feet rather than pinned through the side.
however you do get 18 full inches of elevation.

I can't think of a better option than the scissor jack telescoping legs design. I looked at buying real telescoping tubing but it's nauseating how expensive it is. I don't actually need that much adjustment so I figure i'll just drill through the tubing like 5-6 times per leg.

>>2950757 (OP)
>>2950758
>>2950759
pic related is more or less what i'm planning, if this makes sense.

>>2950761
this should help elucidate further

Get a heavy duty motorized standing desk frame, the kind with 4 legs.
They have a spindle in each leg driven by geared motors.
Seen them for 250 bucks on ebay rated for 400lbs.

>>2950762
>>2950761
I would be concerned with racking with that setup. One side tilting so the whole thing binds and gets stuck.

>>2950757 (OP)
At the risk of asking a stupid question; why not just figure out what your optimum height is beforehand and then just build to that height? Do you need to collapse it for storage or something?

Unless you're moving it through doors often (in which case, wtf why?) just affix it with something that can be removed. For metal tables that's simple. For wood it's just a case of using threaded metal inserts.

>>2950768
I thought about it but they're all of a fixed minimum width which is like 10" more than I want. Plus I'd be worried about the forward and backward stability.

>>2950773
The whole fumehood itself is like 120 pounds. so it's not THAT heavy. I'd figure that the jack would be able to overcome any problems and unstick itself without completely fucking the legs up. but i'm not supremely confident, which is why i'm asking.

>>2950777
>>2950791
yeah i'd prefer to be able to push the thing into my shed for storage when i'm not using it because it is an inconveniently large thing.
i could just make the whole worktop lower but i'd have to be seated the whole time to work at it or be hunched over, which sucks.
removing the fumehood is not a trivial task. it's not that it's really heavy, as much as it's unwieldy. you need at least two people to move it around.

i mean it's really close. bathroom counters are like 30", and the whole hood is 48" tall. so i'd have exactly 2" of freedom on the top. but i have to ramp it up into my shed to get over the door threshold and i don't feel like it's that much margin.

if i had to take the whole top off to put it away, it would never ever move, which means that this big ass thing would live in my garage taking up space forever. which is kind of the reason why i want to build a table for it anyway, so it's on longer taking up space in my garage all the time.

>>2950762
>>2950773
I use these in industrial settings, the key is that the legs are not flat but like a rounded H-profile so that the contact is always convex to convex and it never binds. And a normal coarse thread screw spindle to jack it

>>2950757 (OP)
i build picel on a 3x5x2" welding table and it was fantastic
channel iron rides on the pipe legs so everything is trapped but can move vertically

>>2950757 (OP)
>>2950860
here is a strictly mechanical version shamelessly stolen from some forum. the slide tubes look like sections of pto shaft so i bet its farmerbiltTM

>>2950757 (OP)
I have no clue about sandblasting but it seems like overkill for 3D printing or soldering. That’s even before making a heavy, variable height table. Just get a cheap fan and be done.

>>2950908
yeah you're right but it's "free", and it sucks all the air out. it's perfectly one-directional. you could smoke a cigarette in the hood and pipe it out a window and nobody would know.
i might get into doing chemistry or something later i dunno. i've thought about getting into making my own rocket motors and it could be good to have a hood for that.

thinking about the racking more, i could do two jacks on each side like >>2950862
>>2950860
shows. i'd rather just have to do one because it'd be less tedious to change the height.
looking further into it, i see a lot of people doing it out of wood. i don't know much about woodworking and i don't know if that'd be easier or not? i could believe that it'd be easier to make the telescoping legs because you could get a really close fit so there's less wobble. i don't have much woodworking equipment like planers and shit but i do have family who have that setup. i'm more comfortable chopping and welding a table out of tubing.

https://www.youtube.com/watch?v=LKUVgv_iLtM

>>2950908
sandblasting container only exists to capture the sand for reuse.

>>2950757 (OP)
>well that was about a year and a half ago
"I bet you're wondering how I got myself in this situation" sitcom vibes.

Okay first you need to vent it. So you're permanently installing a vent you're going to attach and detach from. Second you're not actually doing anything you need the hood for if you're 3d printing and if you did (you don't) then you're not going to be fucking moving your printer back and forth you're going to be printing otherwise what is the point of buying the printer. Soldering is just as stupid, if you're going to solder so little that a dedicated hood isn't necessary then a fucking dedicated hood isn't necessary.

what you have is a $20,000 fan that doesn't fit, a steel frame and a filter that still needs to be vented.

A few options:
1. sell it and use the money to buy a 3d printer
2. strip it and use it for a steel frame workspace repurposing the fan and filter
3. put it back in the dumpster
4. get a bigger shop you fucking poorfag

the whole thing is overdesigned and idiot proof, created for real lab work by fucking idiots in the real world. for you and anything you've listed it's an albatross. you need to get over it, get rid of it and actually do the 3d printing, sandblasting or soldering instead of faffing about with a jackoff table that you'll push into storage and never look at again.

>>2950979
face it you're more likely to start smoking than to get into chemistry. plus if you did get into that kind of chemistry (face it you're not) you would need a DEDICATED installed station. my brother used to mix all kinds of shit in his room, including fucking with potassium and making flash paper and shit. it's like 3d printing, you're a fucking idiot if you think you need more than normal circulation and again if you were doing it, you wouldn't be moving it between prints.

>>2950852
>push the thing into my shed for storage when i'm not using it
Doesn't a fume hood require an exhaust connection?

>>2951006
They usually have hepa filters too so if he's not doing super toxic chemistry it's probably fine for soldering and 3d printing.

>>2950757 (OP)
Does it even have a built-in blower? I've installed some of these at my prior job and very few include a blower and are nothing more than a cabinet with a sliding glass door. They have to be paired with a blower of a minimum CFM rating and one as large as you are describing would need 400CFM or more to even work with the glass slid up enough to get your arms under it.
For them to be used safely you need a flow-rate gauge at the inlet side and for the hazard level of the materials and fumes there are required minimum flow rates for the door when open to a 4 inch gap.
If it doesn't have a built-in blower your "free" item isn't really useful and you're better off just selling it. A way smaller fume extractor would be more useful and cheaper than a whole fume hood.

>>2950757 (OP)
Maybe you should scrap it for the value of the various metals.

>>2951022
have you ever scrapped anything?
guessing not since an empty tin box would pay about 80 cents gross then subtract all the fucking around hauling it to the yard. there a reason most scrappies dont drive bentleys

>>2951018
just put a dryer tube on it and vent outside.

>>2951018
for which there are much simpler better solutions that don't require a 1-ton lift table to store in the shed.

Id grow mushrooms with that thing or make crisper abominations

>>2951025
fully assembled it weighs over 700 pounds and there is a lot of 316 stainless in the chassis and copper tubing in the air scrubber.

>>2953589
Yes but all I got is the bare hood without any of the air handling equipment or cabinets.

>>2954429
wait wat?

Is it just the metal enclosure and the glass window?