Everything that has to happen to John’s two-car garage before two Mimaki 3DUJ-553
full-colour 3D printers can live in it — in the order the work should be done, with the
numbers checked against Mimaki’s own Site Requirements Guide rather than from memory.
Plain language on purpose. If a step says “licensed” or “permit”, that part is
not a DIY job — the rest mostly is.
Decision: garage. John confirmed on 30 October 2026 that
the build stays in the garage with two machines. The two warehouse units are not
being taken; those pages stay published for reference only. This is the final layout.
The short version
The printers need an office, not a garage. Everything below exists to turn one into
the other: steady temperature, steady humidity, clean air, clean power, a sealed floor, and a
place to wash the parts afterwards.
Two of them fit, and the room is no longer a guess. John’s builder floor
plan gives the garage as 20 × 20 ft —
400 sq ft, with a 10 ft nominal ceiling on that
sheet. Each printer needs 9.4 ft × 8.8 ft once Mimaki’s
service clearances are added, so two machines claim 165 sq ft —
about 41 % of the floor. The room is big enough.
But they can no longer go side by side on one wall. That layout needs
18.8 ft of an uninterrupted 20 ft wall, which leaves only
1.2 ft of slack — and on the real plan every 20 ft wall is
interrupted by more than that. The wall shared with the kitchen carries the
water heater at one end and the door in from the house at the
other; the front wall is the garage door itself. So the two machines split up into an
L, which the room’s spare depth easily affords. The plan below is drawn that
way.
The checklist
1
Insulate the garage door and the bare outer wall
A garage door is a big uninsulated panel; it will fight the heat pump all day. Use an
Owens Corning garage door insulation kit plus foam weatherstripping
around the perimeter so the door seals when it closes.
Settled 3 November. John confirms the garage exterior wall is
to receive blown-in insulation, and that the garage door insulation kit
above is going in. Blown-in is the right method here for a reason worth putting on paper: every
wall in the garage photo is already finished and painted, and blown-in fills the existing stud
cavity through small drilled holes, so it does not mean opening up and re-drywalling a
finished wall — which rigid foam or batts would have. That is the same question the note
below raises, now answered from the other direction.
The floor plan narrows this job. Of the four walls, the one
shared with the kitchen is an interior wall — the pantry, the refrigerator
space and the water heater are all on it, with heated house on the far side — and the wall
toward the foyer is interior too. That leaves the garage door and
the side wall with the outside door as the surfaces actually facing weather. Insulate
those; do not pay to insulate a wall with a warm kitchen behind it.
Still to confirm on site: this is a three-storey plan and the sheet John sent is
the 1st floor only, so it does not show what sits directly above the garage. If that is
living space, the ceiling is a floor assembly and wants insulating as much as any wall. Ask before
sizing the heat pump.
Check first: in the photo of the garage, every wall is
already finished and painted. Insulation behind finished drywall cannot be seen — confirm
which walls actually have it before buying materials.
2
Heating and cooling — a ductless mini-split
One MRCOOL DIY 24,000 BTU ductless mini-split heat pump. It both heats and
cools, which matters because the target is a narrow band all year.
target 68–77°F (20–25°C)
Mimaki lists two temperature ranges. The machine will operate from
59–95°F, but colour and dimensional accuracy are only guaranteed between
68–77°F. Size the system for the narrow one.
3
Humidity — a dehumidifier and a cheap meter
A Midea Cube 50-pint dehumidifier, plus a hygrometer so you can
actually see the number rather than guess.
Mimaki spec: 35–65 % RH, non-condensing
Aiming at the middle of that band (around 45–55 %) gives you room to drift
on a humid day without going out of spec.
4
Air — decided: filter and recirculate
This was an open choice in the first version of this page. It has been settled:
one BOFA 3D PrintPRO 3 filter unit per printer, capturing at the machine and
returning clean air to the room. No hole in the wall for the printers.
The full reasoning, and what the ducted alternative would have cost you in heating
and cooling, is in Airflow & duct design below.
The ducted system priced on /garage-vent-kit is the option that was
considered and set aside for this garage. That page is still accurate about parts and
airflow if you ever duct a room — it is simply not the design being built here.
5
Electrical — licensed electrician
Per printer: a dedicated 20 A circuit. The mini-split needs its own
240 V run. Each printer should sit behind its own UPS —
a battery box that keeps a print alive through a flicker and shuts the machine down safely in a
real outage.
What draws power
Watts (max)
Plug
Printer main unit
1,300 W
NEMA 5-15P
Printer driver PC
300 W
NEMA 5-15P
Touch-panel monitor
30 W
NEMA 5-15P
Total per printer
~1,630 W
Size the UPS off that 1,630 W number, not off a 1500 VA box. A
1500 VA UPS only delivers roughly 900–1,000 W, which is well under one
printer’s draw. Mimaki’s guide recommends APC SURTA3000XL (2.1 kW)
or APC SMT3000C (2.7 kW) — both 3000 VA class.
Tell the electrician this part explicitly: those two UPS models take an L5-30P
input, which is a 30 A 120 V receptacle, not the 20 A one. Either
run 30 A where the UPS goes, or choose a UPS of equivalent wattage with a standard
5-15/5-20 plug.
On John’s standby-generator question: the UPS covers dips and a safe shutdown,
which is what protects a part mid-print. A standby generator is optional — Mimaki notes that
for extended outages both a UPS and a generator can be used, but nothing requires one.
6
Seal the floor — before the machines arrive
Epoxy or a concrete floor coating, for dust control. Bare concrete sheds fine
dust continuously, and these printers want a typical office environment.
Work the water heater corner into the coating plan rather than around it later
— the builder plan puts the heater inside the garage, on the kitchen wall, and whatever
clearance and service access it needs is floor you do not get to use.
The slab is not flat, and that is on purpose — noted 3 November.
The garage floor falls about 2% for water drainage, and John plans to
shim the machines to bring them level on it. Two consequences worth having in
writing. First, the coating goes on keeping that fall — nobody should self-level
this floor flat and quietly take the drainage away. Second, the shim stack is part of the
install rather than an afterthought: 2% across a 9.4 ft printer bay is about
2 in of fall end to end, and a 1,323 lb machine wants continuous
bearing under each foot, not a packet of washers. Worth confirming the actual fall with a level
at the two bay positions before install day, because 2% is the design figure, not a
measurement.
This has to happen before delivery. Once two 1,323 lb
machines are in place they are not coming off the floor again for a coating. The slab in the photo
is bare and has an open control joint — fill it as part of the prep.
7
Plumbing — the cleaning station and where the water goes
No separate utility sink. The three-tank cleaning station has its own built-in
sink, so the station is the only wet fixture in the room. It sits at the plumbing that is already
there, and nothing else in the layout needs a basin.
The support material on these printers dissolves in water, so parts come out of the printer and
go into an ultrasonic bath. It has to take Mimaki’s largest model, about
20 × 20 × 12 in. John’s candidate is the
UPCorp three-tank custom automated ultrasonic cleaner.
The dissolved support material must not go down the sewer. Collect it in drums,
or filter it, per Irvine / Orange County rules — confirm with the city which one they want.
This is not a formality: the removal process commonly runs with additives such as potassium
hydroxide solution, and that is not residential-drain waste.
Swapping to a tankless water heater is compatible with the station. Size it for the
station’s hot-water feed. Plumber plus permit.
8
Safety gear
Goggles
Chemical-resistant gloves
Ventilation at the operator position — whichever air option you chose in step 4
9
Permits
A City of Irvine residential permit is needed — John has confirmed this.
While you are talking to them, check the home-business rules as well: running a
printing business out of a residential garage is a separate question from the construction work.
10
Before install day — tape it out
Put painter’s tape on the floor: two 9.4 × 8.8 ft
rectangles for the printers, plus the cleaning station position. Walk it. It is the cheapest
possible way to find out that something does not fit.
The swing of the door in from the house is settled as of 1 November
— John confirmed both hinged doors open outward, so neither one eats floor
inside the garage, and the drawing now shows them that way. Two things are still worth taping
specifically, because they are the ones the drawing cannot settle: the clearance the water
heater needs and the real clear span of the kitchen wall between the heater and
the house door. That span scales off the plan at roughly
11 ft, which leaves a 9.4 ft bay about 1.5 ft of
room — comfortable if it is right and fatal if it is a foot narrower. It is a tape-measure
question, not a drawing question.
The exterior door is now in its proper place — settled 3 November.
John asked on 2 November for it to be moved to its proper location and
swing, and the builder sheet settles it: the door belongs in the right-hand wall at the
rear end, immediately past the water-heater nook. The drawing had it about a foot too
high, overlapping the water heater — that overlap was the error. It now sits
2.5 ft from the rear-right corner, 3 ft wide, still swinging
outward as settled on 1 November, so it takes no floor inside the garage.
Worth a tape measure on site all the same: the water-heater nook is drawn as a bump-out on the
builder sheet and as an inset here, and that difference is exactly the kind of thing that moves
a door jamb by a few inches.
Where everything goes — floor plan
Drawn from John’s builder floor plan. The two machines are in an
L, not side by side, because the kitchen wall has the water heater on one end and
the door in from the house on the other. Each keeps its full service clearance; the wet work —
the three-tank post-print station, which carries its own integrated sink and is the only wet
fixture here — stays by the plumbing stub and well away from the machines.
What is measured now, and what is still scaled off a drawing.
Two numbers are printed on John’s plan and can be relied on: the garage is
20 × 20 ft, and the 1st-floor sheet is noted
10 ft ceiling height. Everything else taken from that plan — the
water heater in the kitchen-wall corner, the door in from the house
through the drop zone, the outside door on the side wall, and the
~11 ft clear span between heater and house door — is
scaled off the drawing, not dimensioned on it. Tape those before ordering.
The garage door, the two electrical panels about 2–4 ft
back from the door opening, the plumbing stub beside them, the
bare concrete slab with its open control joint and the finished
drywall still come from John’s photo, unchanged.
One caution on the ceiling: 10 ft is the sheet’s figure for that
floor, and the garage bay is not called out separately — the drop zone and the bath
are, both at 9 ft. A garage commonly loses height to a door header or to the floor
structure above. It clears the 61 in machine and the 61 in crate either way, so nothing
here depends on it; confirm it anyway before anything gets hung from the ceiling.
Settled, 26 Oct: the door to the house is not where this plan had it — and that
changes the layout. The previous version of this page placed that door on the right-hand
wall, called the position provisional, and said John’s sketch should settle it. The sketch
settles it: the door is on the kitchen wall, entering through the drop zone, and the
water heater is on that same wall at the opposite end. So the old
1.2 ft squeeze against a provisional door is void — and it is replaced by
something firmer, because an 18.8 ft side-by-side run needs a 20 ft wall with nothing on
it, and that wall now has two fixed obstructions. Hence the L. The good news is that the
room affords it comfortably: two machines with full clearance take
165 of 400 sq ft.
And one thing the plan contradicts, flagged rather than quietly fixed. The
mini-split head was drawn on the left-hand wall with its line-set run straight out through it. The
builder plan shows that wall as an interior one — foyer and a bedroom on the far side
— so a line-set cannot simply pass through it to the condenser. The head is redrawn on the
right-hand wall, which the plan does show meeting outside air. This is the one place where the plan
and the earlier photo reading disagree, so treat the head’s position as the open question and
settle it with the installer: what matters is which wall actually gets you outside to the condenser.
Airflow & duct design
In plain terms: nothing is blown outside. The air in this room gets cleaned and
kept, rather than thrown away and replaced.
How the air actually moves
The BOFA unit does the cleaning, at the machine. One
BOFA 3D PrintPRO 3 sits next to each printer and connects to the printer’s
own rear outlets. Fumes are caught where they are made, before they reach the room. The air
passes through a HEPA filter (the particles) and then a carbon
filter (the smell and the vapours), and comes back out into the room clean.
The mini-split does the conditioning. Its indoor head hangs on an insulated wall
and keeps the whole room in the 68–77 °F band while moving the air around. The only
hole it needs is the small line-set penetration to the condenser outside — a pipe bundle a
couple of inches across, not a vent.
The dehumidifier rides along. It sits in the same room air and pulls it back to
35–65 % RH. It needs no duct either.
So the only things that cross the wall are a refrigerant line and a drain. Everything
else is a closed loop: machine → filter → room → machine.
Why not duct it outside, which is what the printer’s own guide assumes
The Mimaki rep sized the ducted version properly: the printer has three rear exhaust ports, and
venting them wants about 360 CFM per machine pushed through the wall. That design
works, and it is cheaper in parts. It loses on the thing that matters in a garage:
Every cubic foot you blow out has to come back in. Two machines venting
360 CFM each is roughly 720 CFM of air leaving the room — and the
same 720 CFM of outside air being pulled in through whatever gap it can find, at whatever
temperature and humidity the day happens to be. In a room whose entire purpose is holding
68–77 °F and 35–65 % RH, that is the mini-split and the dehumidifier
fighting the open wall all day, every day. You would be paying to condition the outdoors.
Recirculating costs more in equipment and nothing in makeup air. It also removes the whole
back-draft question — if there is ever a gas water heater or dryer sharing this garage, a big
exhaust fan can pull combustion gases back down its flue, and a closed loop simply cannot.
What it costs you instead: filters
This is the trade. A recirculating unit only keeps working while its filters have life in them, and
they are a consumable.
Pre-filter — the cheap one that catches the coarse dust. Check monthly,
expect to change it a few times a year.
HEPA + carbon — the main cartridges. Typically around
12–24 months on moderate use, sooner if the machines run hard.
Watch for the warning before the smell. The unit reports filter condition; the
honest signal that carbon is spent is that you start noticing the print smell again. Do not wait for
that — by then it has been leaking into the room for a while.
Budget the cartridges as a running cost from day one, the same way you would budget ink.
Confirm the exact intervals and part numbers with the BOFA supplier for the PrintPRO 3 against two
3DUJ-553s — duty cycle drives it more than the calendar does.
Electrical design
The panel is on the wall to your left as you stand inside facing the garage door, about
2–4 ft back from the opening — that is where the photo puts it, and the runs below are
measured from there. All of this is a licensed electrician’s work and needs a City of
Irvine permit.
The circuits
Circuit
Rating
Feeds
Printer bay 1
20 A / 120 V
Printer, driver PC, monitor (single-phase, per Mimaki)
Printer bay 2
20 A / 120 V
Printer, driver PC, monitor
Mini-split condenser
240 V, dedicated
Size to the unit’s nameplate — a 24,000 BTU DIY unit is typically 30 A
Room loads
existing
Dehumidifier, lighting, general outlets
Each printer gets its own circuit. Two machines sharing one is the single
easiest way to lose a long print to a tripped breaker.
The UPS, and the number to be careful about
A UPS sits between the wall and the machine. It rides out dips and flickers, and in a real outage it
holds the printer up long enough to shut down cleanly instead of dying mid-model.
A 1500 VA unit is not big enough, and this is worth getting right before you buy two of
them. A 1500 VA UPS delivers roughly 900–1,000 W. One
printer alone is rated 1,300 W, and with its PC and monitor the bay is about
1,630 W. Put that load on a 1500 VA box and it overloads and drops the
machine — at exactly the moment it was bought to help.
Mimaki’s own guide recommends 3000 VA-class units: the
APC SURTA3000XL (2.1 kW) or APC SMT3000C (2.7 kW).
Tell the electrician this part explicitly: both of those take an L5-30P plug, which
needs a 30 A 120 V receptacle at the printer bay, not the 20 A one.
Either run 30 A where each UPS lands, or pick a UPS of equivalent wattage with a standard plug.
A standby generator stays optional. The UPS is what protects the print; a generator only
matters if you want to keep working through a long outage.
The runs
From the panel, surface conduit along the walls to each printer bay — shown as
the dashed lines on the floor plan. Surface-mounted is normal and correct in a garage: the walls are
already finished, and running conduit on the surface avoids opening them up. It also means a circuit can
be added later without demolition.
Does the existing panel have room?
Rough arithmetic, so you know whether this is a small job or a service upgrade:
Load
Approx. watts
Printer bay 1
1,630 W
Printer bay 2
1,630 W
Mini-split, running
~2,500 W
Dehumidifier
~500 W
BOFA units (2)
~400 W
Total, everything at once
~6,700 W ≈ 28 A at 240 V
Against a typical 100 A or 200 A residential service that is comfortable — this reads
as a few new circuits rather than a service upgrade. Treat it as a sanity check, not a design.
The electrician still has to do the real load calculation against what the house already draws, and the
photo shows two panels, so which one has spare breaker spaces is a question to answer on site.
Budget & utilities — John’s questions, answered
The questions John raised on 1 and 2 November. The
first three are written as options rather than a recommendation, because every one of them is a
judgement about how much protection is worth buying. Prices were checked on 1 November 2026 and are approximate —
street prices on all three move, and the installed ones depend on the site. Get a quote before
committing to anything in the right-hand column.
a. Power backup — what happens when the power blinks
The reason this matters is on this page already: a printer draws about
1,630 W all in, so the two machines together are about
3,260 W. A UPS of any size buys minutes, not hours. Its
real job is to carry a flicker without ruining the print and to shut the machine down cleanly in a
genuine outage. Only the generator changes that.
Option
What it is
Approx. USD
Covers
1. APC Smart-UPS SRT 6000VA SRT6KXLT
True online double-conversion. The machine runs off the inverter all the time, so it never
sees a sag, a spike or a transfer gap — the usual recommendation for UV flatbed printers.
$7,300–9,000
both printers from one unit (6,000 W rating vs 3,260 W draw)
2. APC Smart-UPS SMT3000C line-interactive
Budget tier. Conditions the line and switches to battery on a dropout, so there is a brief
transfer. Lighter protection, and the usual choice when the price of option 1 is the problem.
$2,100–2,950 each
one printer each (2,700 W output vs 1,630 W draw) — so two units
3. Generac home standby, 10–14 kW
A different thing entirely: hours of runtime, not seconds. Only worth it if John wants to
keep working through an outage. Still wants a UPS in front of the printers, because a
generator takes seconds to pick up the load.
$6,000–13,500 installed
the whole garage, and usually the house
The quoted range on the generator is genuinely that wide. Published 2026 figures
for a 10–14 kW Generac run from about $5,500 on natural gas at
the low end to $13,500 installed with pad, transfer switch and permit.
The spread is fuel type and site conditions, not vendor margin. Two quotes, minimum.
b. Epoxy floor coating
The garage is 20 × 20 ft = 400 sq ft, so
the totals below are for the whole floor. All three want the slab clean, degreased and acid-etched
or ground first; skipping that is the single most common reason a garage floor coating peels.
Option
What it is
Per sq ft
400 sq ft
1. Rust-Oleum EpoxyShield garage floor kit, DIY
Water-based, roughly 50% solids. A weekend job. Fine for a garage that parks cars;
thinner film, so it is the one most likely to need redoing.
~$0.30–0.50
~$260–400 (2 kits)
2. 100%-solids epoxy e.g. ArmorPoxy, DIY-pro
One coat builds the same film as two coats of the kit above. Harder, far better against
solvent and ink spills, less forgiving to apply — it goes off on a clock.
~$1.40–2.50
~$560–1,000
3. Polyaspartic contractor-installed
Most durable and quickest to cure — typically back in service the next day. UV-stable,
does not yellow. This is the one you pay somebody to do.
~$5–12
~$2,000–4,800
For this room specifically: the thing the floor has to survive is not tyres, it is
dropped solvent and ink from the cleaning station. That argues for option 2 or 3 in
the strip of floor around the post-print station even if the rest of the garage gets option 1.
c. The water spigot in the bottom-right corner
What it is for. The spigot marked at the bottom-right of the drawing is the
cold-water feed for the post-print station’s integrated sink. That corner is
the nearest existing hookup to where the station stands, which is why the station sits where it
does rather than anywhere else along the front wall. There is no separate utility
sink on this plan — the three-tank unit has its own, and this spigot feeds it.
Drainage is the matching question and it is not settled on paper: confirm with the plumber whether
the station drains to the existing stub or needs a run.
d. Is there room for a workbench?
Yes — one place, and it is scaled off the drawing. Asked
2 November. The free floor is the right-hand wall, between the mini-split head and
the electrical panels: that strip measures roughly 6 ft long by
2.5 ft deep on the plan, which is a real bench rather than a shelf. Everywhere
else is committed — Printer 1 takes the left wall, Printer 2 the kitchen-wall
clear span, the cleaning station the front corner by the spigot, and the front wall itself is
the 16 ft garage door.
The binding constraint is not space, it is code. The panels need
36 in of clear working space in front of them, full height, kept clear
permanently. A bench built into that zone is a failed inspection rather than a tight
fit, so the bench stops short of the panel end of the wall instead of running the full length.
Now drawn — confirmed 3 November and on the plan as the dashed
rectangle against the right-hand wall. It clears the relocated exterior door (which opens
outward in any case) and stops short of the panel working space rather than running the full
length of the wall.
One thing the plan does not cover: getting them in
Each printer ships in a crate measuring 95 × 71 × 61 in and weighing
1,540 lb, and Mimaki’s guide says a forklift with long forks or fork
extensions is required to get it off the delivery truck. On a residential driveway that is
not a given — sort out the unloading plan and the path from the truck to the garage with the
dealer before a delivery date is set. Keep the crate, pallet and brackets afterwards; they are what
makes the machine movable again later.
The floor plan closes one option: they come in through the garage door, and only
through it. The other way in is from the house through the drop zone, and that route goes
up steps under a 9 ft ceiling — the garage slab sits below the house floor, and
the plan adds that the step count “may vary due to site conditions”. A 1,540 lb
crate measuring 95 × 71 × 61 in is not going that way. Whatever
the unloading plan is, it ends at the driveway and goes straight in the front.
The numbers, from Mimaki’s Site Requirements Guide
Item
Specification
Printer size (W × D × H)
89 × 59 × 61 in · 2,250 × 1,500 × 1,550 mm
Printer weight, operating
1,323 lb · 600 kg
Space with service clearance
112.2 × 105.2 in · 9.4 × 8.8 ft
Operating temperature
59–95°F · 15–35°C
Temperature for guaranteed accuracy
68–77°F · 20–25°C
Humidity
35–65 % RH, non-condensing
Dust
typical office environment
Power, main unit / PC / monitor
1,300 W / 300 W / 30 W max
Supply
single-phase 100–240 V, 50/60 Hz, NEMA 5-15P
UPS recommended by Mimaki
APC SURTA3000XL (2.1 kW) or SMT3000C (2.7 kW), L5-30P
Rear exhaust ports
three × 5.125 in · 120 cfm per port, or 360 cfm combined
Shipping crate
95 × 71 × 61 in · 1,540 lb · forklift required
Where this page and an earlier plan disagree, these are the numbers that win —
they are read straight from the manufacturer’s guide for this model.