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Forum topic by phk posted 02-18-2019 09:05 PM 1157 views 0 times favorited 17 replies Add to Favorites Watch
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19 posts in 3898 days

02-18-2019 09:05 PM

Topic tags/keywords: electrical table saw

I am having a new home built and get to plan my shop from scratch. The shop is a second two-car garage space dedicated to a shop but with the idea that it could be converted to a garage (not in my lifetime, however). Construction has not yet begun, but will soon. I have the layout of my equipment pretty much decided as well as a plan to power my equipment with mostly wall and ceiling receptacles with drop cords where it makes sense. I’m undecided about my table saw, though. It is, of course, in the center of the shop. I really would rather not have a cord drop from the ceiling even though it could be at the right side of the saw where it’s unlikely to be a problem. My other option is to bring it up through the concrete floor. A floor receptacle flush with the floor doesn’t seem to make sense. Even if placed tight to the table saw it seems like it would be vulnerable, especially if water were ever an issue. I could also stub a conduit up through the floor and install a “monument” type receptacle over the conduit, again, tight to the table saw. The only problem I see with this is if any one wanted to convert the space back to a garage (although I guess it would be a simple matter to remove the receptacle and conductors and patch the floor). The other issue might be flexibility of the table saw location although I can’t imagine I would ever move the saw. How have others here addressed this issue?

-- PHK - Tahoma, CA

17 replies so far

View bmerrill's profile


127 posts in 1565 days

#1 posted 02-18-2019 09:59 PM

Install several floor boxes. Use something like the Hubbell 5511 Floor Box, install it flush.

-- Woodworking, the transformation of nature to culture.

View BFamous's profile


344 posts in 1613 days

#2 posted 02-18-2019 11:27 PM

Honestly, I probably wouldn’t do the floor boxes installed in the concrete – but I also wouldn’t just do concrete floors. Starting from scratch and with “unlimited” liberty, I’d probably put a floating floor of sorts. It could be as simple as a 2×4 grid with 3/4 ply on top, or something fancier (which I am certain there are options out there. But do it in like 2×2 squares so they can be lifted / replaced easy.

Putting a floor over the floor would give you the option to install floor boxes in the wood floor without any concerns of removing them later. Plus, if you rearrange the shop in the future it’s easy to move the floor boxes too.

You could even go real fancy and put a down draft vent somewhere in the layout to hook to a central bad so you could sweep all of your dust easily.

The added bonus is that a raised floor should be better on your feet than standing on cold concrete all day…

-- Brian Famous :: Charlotte, NC ::

View pottz's profile


26548 posts in 2476 days

#3 posted 02-18-2019 11:46 PM

yeah id avoid floor boxes too,between the possobility of water,dirt could be a a big fan of keeping everything on wheels,you might think you have the layout exactly the way you want but ive rearranged my setup many times over the years.i have ceiling drops in several places,110 & 220v and its not really an issue,plus its easy to add or move them as needed.

-- working with my hands is a joy,it gives me a sense of fulfillment,somthing so many seek and so few find.-SAM MALOOF.

View JohnJenkins's profile


14 posts in 2159 days

#4 posted 02-19-2019 12:01 AM

I just did this about a year ago – a large shop space with headers installed where garage doors could be added in the future.

I installed both 110 & 220 flush to the concrete floor (I later converted them to tombstones). I also installed 6” dust collection duct under the slab right next to the electrical. I was close, but I wish I had placed it about a foot over in one direction. The truth is you don’t know how you’ll set up shop until you move in. If you’re nervous or undecided where to place it, put it in two places knowing you’ll end up covering one set with flooring.

If you’re going to have an out-feed table, you have a good amount of leeway where to place the elec/DC.

I ended up clustering my big equipment in the center of the room and they are all powered and DCed through the slab. It’s a very clean look – nothing hanging down from the ceiling. Speaking of which consider vaulting the ceiling. Everything feels more expansive with that space overhead.

I installed an inexpensive manufactured floor over the concrete and really like it. If you did this, the extra outlet/dust collection would be covered and forgotten pretty soon.

On the subject of outlets, it is impossible to have too many – both 110 and 220. Even if you don’t think you need a bunch of 220 now, you will as soon as the sheet rock goes on. Then it’s too late to do it cleanly. Most folks will recommend a 100 amp panel. With new construction, a 200 amp panel probably would only cost about $100 extra. So you’ve got a bunch of extra space – never a bad thing.

Don’t forget an industrial sink and toilet. They’re as essential as dust collection (especially for us older guys).

Best of luck!

-- Slow but.............well just slow.

View evilboweivel's profile


3 posts in 1224 days

#5 posted 02-19-2019 01:59 AM

Feed the saw under the floor with pipe at l;east 6” above the floor
I would definitely have a sub panel installed just for the shop. Everything wired from it except the lights and one dedicated 4 outlet receptacle for battery charging. Then shut the main breaker when you are not out there using the shop.
Didn’t think I would ever have grandkids when i wired my basement shop 20 years ago, now have 14 grandkids.
Now really need to bite the bullet and install a subpanel in the shop and refeed all of it as they are getting old enough to want to be down there.

View BlueRidgeDog's profile


922 posts in 1271 days

#6 posted 02-19-2019 02:31 AM

I am not that fancy. I have an outlet on the wall and the saw just plugs into it with a longer cord. My scrap bucket sits on the right of the saw and it is a dead space that then leads to clamp storage so I never walk over there (can’t). I worry about the dust in the shop and the fire risk, so I avoid outlets that will collect it…have even installed the self closing ones where needed.

View ibewjon's profile


3020 posts in 4285 days

#7 posted 02-19-2019 03:43 AM

First step, use conduit for wiring, 3/4 ” can serve up to 50 amps. Above 50 amps, go to 1”. Being an electrician first, I have a double receptacle every other students, with a two gang on every student in between for 240 volt. Use all deep boxes, you will be sorry if you don’t. Use GFI receptacles to feed each 120 volt run. Required if inspections, and also to stay safe. Put lighting on 2 separate circuits, so you will not be in the dark if something trips. As for floor boxes, I have one for my TS, which won’t move because shop is too small. I ran 4” PVC with long sweep bends under floor for dust, all above floor duct is steel for grounding. My floor box has a combination receptacle, 120 and 240.v. if you want to be able to remove receptacles later, use a tombstone box, just put a female adapter on conduit flush with floor, and a nipple of any height can be installed later. If I had a larger shop, I would have installed Walker duct down center of concrete floor, which has a threaded hub every 24” and receptacles screw into this. Got kind of long, but it is nice to start from nothing and do it the way you want. With conduit, you can install plenty of boxes and add wire where needed, leaving spares empty till needed. Enjoy the process.

View therealSteveN's profile


10186 posts in 2066 days

#8 posted 02-19-2019 04:54 AM

I did much the same as you are now doing with building from ground up. My electrical plan was different from others I have seen, but I like it. For me TS use is most frequently done for stock prep, so I was also including the jointer, and planer in that “zone” I constructed a 4 sided tower with 2’ wide sides floor to ceiling. I had already run 5, 20 amp lines from my box up into the ceiling, and coming down through the center of my tower. One each for the 3 tools I’ve mentioned, and one for a Dust collector with gates to each tool, and a fourth for 110 tool usage. I’ve got it set, and have trialed all the tools around it with pretty good success. I frequently see others place these tools in close proximity, but have never seen a tower to serve them. I had at one time entertained using the electrical drops you spoke of, but I have already paid for all of the tower, sans sheathing, and just one of those drops, if done to code coast almost twice the price of placing 5 lines, with no trip hazard as all the lines are behind the tools, and I’ll just be operating out front.

My initial thought was to drywall it like the rest of the shop walls, but after using it I think I’m going to cover at least part of it with 1/4” pegboard, and use several of the many available hook/shelf assemblies to hang the associated sleds, and safety devices, probably a few jigs, and push pads for the jointer. The stuff you are always looking for, and it’s just over there.

-- Think safe, be safe

View ArtMann's profile


1483 posts in 2308 days

#9 posted 02-19-2019 08:02 PM

My shop has morphed from one thing to another so many times that I have learned to place outlets in a way that will allow for change. I have what most people would consider an excessive number of 120VAC and 240VAC outlets distributed all along three walls. My shop is only 6 months old and I am glad I did it that way due to unforeseen changes to the original equipment plan. The cord for the table saw stretches from the wall to the middle of the room but is not in an area with a lot of traffic.

View MNgary's profile


318 posts in 3909 days

#10 posted 02-19-2019 10:34 PM

I would have my 110V lines on 20 amp breakers and only have a few outlets on each breaker. I also would have a light switch for each work section so wouldn’t have the entire workshop drawing electricity for lighting if I am only doing design work at my workbench or veneering at my glue station.

-- I dream of a world where a duck can cross the road and no one asks why.

View phk's profile


19 posts in 3898 days

#11 posted 02-19-2019 11:47 PM

Thank you all for the valuable input. You have all given me a lot to think about. One question, though: Many of you have stressed the importance of having more outlets than I’ll think I need and I am planning on doing that. The only 240v piece of equipment I have now is the table saw; everything else is 110v. The only things I’ve considered (or have room for) is a scroll saw and a lathe. The lathe could require 240v so I should plan for that. I can’t imagine what other equipment I would buy that would require 240v or even where I would put the outlets. Am I missing something?

-- PHK - Tahoma, CA

View therealSteveN's profile


10186 posts in 2066 days

#12 posted 02-20-2019 01:02 AM

I can’t tell you what to spend, because at the end of the day 220 lines cost more, but I have 4 outlet boxes for 110 every 8 foot around the perimeter of my “working area” I have (11) 220 lines from a 50 Amp for my welder to a spare 30, for ???? future maybe, and the rest are all 20Amp for tools I have or have considered. I am able to move many of them around as work flow dictates, and having more than I need is a lot better in my estimation than having all that drywall finished, and figuring out I want 2 more, one here, and one way over there.

Point is they will never be as low cost to put in, nor easier to do, than right now.

Stuff you may not have now, but could find yourself needing down the road that can often be said to be 220.

Compressor with a big tank
Table Saw
Bigger bandsaw
Wide Sander
Dust Collectors over 2 Hp

I was asked to show pics of the tower I spoke of earlier. Been sick with a cold, felt better after dinner, but after walking back to the barn realized I had NOT turned on the electric. So pics are weird due to flash only illumination. One of these days I’ll get this all done. I promised another LJ to do a shop pic thing from grading to finished.

View of the bottom of the tower from front of the shop area. 12’ walls I couldn’t get the entire thing in one shot.

Top of the tower, shows junction box where all the collected lines got distributed.

Wall showing spacing of electrical outlets (110) around perimeter of the shop area. Other 220’s are here and there.

-- Think safe, be safe

View Smirak's profile


123 posts in 2010 days

#13 posted 02-20-2019 05:03 PM

raised floor with electrical and vac inside the raised floor. That’s what my plan is when I build…

View WayneC's profile


14359 posts in 5589 days

#14 posted 02-20-2019 05:12 PM

I wired in lighting in my garage shop with 110 and 220 outlets in the ceiling. I have a number of cord reels from the overhead. I have three 220 wall outlets as well. One is 40 amp for a welder. Each of the 220 outlets is on it’s own breaker. Be sure to have spare breaker space in your breaker box so you can expand in the future if you discover a new hobby (such as welding in my case)

-- We must guard our enthusiasm as we would our life - James Krenov

View WayneC's profile


14359 posts in 5589 days

#15 posted 02-20-2019 05:15 PM

My 220 woodworking tools are Lathe, Table saw and Dust Collection. I’ve lusted after 220 bandsaws for years. I also have two 220 welders and a plasma cutter.

-- We must guard our enthusiasm as we would our life - James Krenov

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