# Stainless steel sheet Metal working questions???



## fge

I just accepted a job after a down period. It is not my perfect choice in work but I cannot be choosy at this time and if done correctly this job will be profitable for us.

I am building 10 workstations with 3 sides and a desk top. The units will be 3' X 6' X 4' tall and I am purchasing 4' X 12' Stainless Steel 14 gauge sheets. The specs indicate 14 g Stainless to be laminated over 3/4" cabinet plywood. So the interior of the workstations will have a wilsonart laminate and the exterior will all be Stainless steel.

At the ends of each part the stainless steel will bend around the plywood as such: "U". So using angle iron I will build my own "brake" to make nice even bends.

My one issue will be cutting the Steel. Since they are 4X12 there will be an issue with cross cutting.

The way I want to cross cut is using our newly acquired Vertical Panel Router. If I am able to find a router bit that cuts metal, similar to bits for a Rotozip, I can cross cut with high accuracy.

I have considered maybe simply mounting my jigsaw to the Verticle Panel Router sled and use a fine metal cutting blade and let the sled make the cut very straight.

Then I have also considered mounting my circular saw to the Panel Router sled and using an abrasive blade. But that would mean some fairly moderate modifications to the Panel Router sled. I am thinking the jigsaw will mount very easy just using a few self tapper screws.

I don't have the funds available to buy any Shearing machinery and the initial draw will not be enough to outsource any shearing services so I hope to do all of my own cutting.


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## wiswood2

I was a sheet metal worker for 40 years and you better take a look at the 14 ga.ss be four you buy it and see what you are getting your self in to . there is no way you are going to bend it with a home made break out of angle iron .14 guage is a little under 1/8 in thick.I wish you luck.
Chuck


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## Charlie5791

The problem you're going to have with cutting it is that you need a thin blade and you have to cut fast. Any dilly dallying and you'll blue the stainless and you won't be able to just polish it out. I've cut it with an angle grinder and a thin abrasive wheel. You could *probably* find a thin wheel that'd fit a circular saw. A fine blade on a jig saw will probably work, but it will look like crap and you'll have a lot of cleaning up to do.

Keys are thin and fast.

You could also run this to a sheet metal shop and have them shear it and it would probably cost you less than buying an angle grinder and wheels 

AND you'd have a nice clean cut. Heck, get them to brake it for ya. Cheap and fast and you concentrate on what YOU do best and have the equipment for.

Adhering the stainless to plywood…. clean that stainless REAL well. Get any oil off of it and then rinse it and dry it and then wipe it all down with DNA or Isopropyl. Liquid nails makes a polyurethane adhesive version and that works great bonding stainless to wood. You could use Sika Flex or 3M 5200. You want a true poly adhesive. These are not gorilla glue. Oh and abrade the stainless with 60 or 80 grit.


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## fge

Thanks Chuck. Approx what thickness is 20 gauge? I am going to ask if 20 g can be used as 14 g seems over kill. This will be for the border patrol.


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## fge

I use a commercial grade contact cement spray that comes in a large propane style tank. I am not at the shop right now and I cannot remember the name but I can say it is some of the strongest glue for laminate and other types of glueing together. The glue is sprayed to both mating parts and air dry a short period of time and the two surfaces make immediate contact. Very easy stuff to work with and sprays on nicely with the gun we own.

I was hoping this glue would work out since we have about 50 lbs of the glue, plenty for this job.


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## Charlie5791

14 gauge stainless is .0781
20 gauge is .0375

For reference, I have an 18 gauge stainless steel sink and that's considered a heavy gauge for a stainless sink.


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## Loren

Stainless is harder to bend and cut than regular steel.

How wide do you need to bend on a brake?

You can get these thin cut-off wheels and mount them
on an angle grinder. I do it all the time. They are thin 
and flexible so they don't cut straight all on their own, 
but being so thin they cut fast and cut cooler. Assuming
you need just one clean edge I suggest making a 
straight edge jig out of angle iron or steep bar to run 
the wheel against. You put the bar on top of the metal
and use it as a guide to cut and grind the edge at the 
same time. If you carve up the guide bar too much you
can flip it or grind and file it straight.

I guess you could do the same sort of thing with a
circular saw but as mentioned, heat can be an
issue. You might call Dino at Eurekazone and
ask him about cutting stainless with his track saw
system. He probably knows what works.


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## fge

Thanks Charlie. I doubt they will approve 20 g. I do think 14 g is likely thicker than needed since 3/4" plywood will be the substrate.

I wonder what dictates they need 14 g. I wonder since it is Border Patrol maybe they feel that this workstation might somehow offer some protection from would be violent people.


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## fge

Loren, who is Dino at Eurekazone?


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## WoodKutter

Jerry, Stainless is very difficult to work without the right tooling. Also you didn't say what series of SS you will be using. You would be much better off finding a local sheet metal shop. They would be able to shear the sheets to size, bend the brakes you need and if there are any holes, they can punch them also. The savings in time, tooling and scrap ( not to mention hair ) will most likely be to your advantage. Contact a couple of shops, supply your needs and get a quote. If they do the work, they may even have the material you need on hand.

Gary


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## TopamaxSurvivor

Jerry, Fed specs are always over kill! ;-)) My policy is not to do business with the Feds unless I am sub to a contractor who will pay me in 30 days whether they get paid or not. That policy has served me very well for over 20 years. Don't ask why I established it. I hate remembering stuff like that ;-))


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## rockindavan

I second finding a place to shear and bend the metal for you. Its simple with the right tools but miserable without.


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## fge

Guys I think I am leaning towards letting the shop do the shearing and bending for me. They said they woould and they recommended that I let them do it. Thanks for the advice.


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## waho6o9

I would make the "U" shape 3/4 plywood and take it over to the sheet
metal place and have them fit a sample piece so everyone's 
on the same page.

Excellent advice on going to the sheet metal shop and have them do what
they do best.


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## KayBee

I work around stainless. Have the shop do it. You really can't sort of 'jerry rig' this and have good, consistent results. You might get lucky on some of the cuts or bends, but not all of them on all the pieces.


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## wiswood2

I have delt with the feds and they dont like to pay for at list 60 days. Have a shop do it is your best bet. at least if they screw on up they have to deal with it.good luck
Chuck


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## Finn

I am also a retired sheet metal worker from Wisconsin. I agree, have a sheet metal shop build it for you. My first impulse is to cut the stainless and weld together at the corners. 
The dimensions you mentioned will require this at least one welded corner anyway. The sheets I have worked with were 10 feet long. Cutting stainless is hard to do because it "work hardens" A sheer gets around this problem.


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## crank49

14- 0.0747- 0.0641- 0.0785- 0.0781
15- 0.0673- 0.0571- 0.0710- 0.0703
16- 0.0598- 0.0508- 0.0635- 0.0625
17- 0.0538- 0.0453- 0.0575- 0.0562
18- 0.0478- 0.0403- 0.0516- 0.0500
19- 0.0418- 0.0359- 0.0456- 0.0437
20- 0.0359- 0.0320- 0.0396- 0.0375
21- 0.0329- 0.0285- 0.0366- 0.0344
22- 0.0299- 0.0253- 0.0336- 0.0312
gage- mild steel- aluminum- galvanized- stainless 
Hope that chart reproduced ok.
One other warning, if you make a bending brake out of regular steel, where it scrubs the surface of the stainless will cause rust.


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## upinflames

You also want to take a magnet with you when you purchase the stainless, true stainless will not hold a magnet, therefore it will not rust when hit with the shear or brake.


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## crank49

Dustmagnet, it makes no difference if stainless is magnetic or not. Some of it is magnetic and some of it is not. Some stainless alloys start out non-magnetic and become magnetic when they are worked, as in bent or pressed. It has to do with whether the alloy is martensitic or austenetic.

The cause of rust on stainless steel is due to carbon steel tools scrubbing the passivated protective oxide layer. I work in a fabrication shop where we work with dozens of different alloys of stainless. they all can rust if not protected. we have to cover tools, work tables. dies etc. to prevent contamination.


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## MrRon

Even 14 ga SS may be too thick for the average sheetmetal shop to handle You need to visit the shops in your area to see who can handle it. I would definitely farm that part of the job out.


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## fge

I really do appreciate all of the input everyone. I did close the deal on this job and will be following everyone's advice. I am going to have the metal shop shear and break the Stainless Steel at the proper bends. So I am looking forward to this job and hope it will be a great job for us. I will have to post in about 5 or 6 weeks as to updates. Certainly I will have to take some pictures as this will definitely be a one of kind for us. We are not a metal working shop but will surely enjoy and welcome the challenge.

THanks a ton guys. Jerry


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## waho6o9

Very good Jerry.


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## roman

Never overstep your bounds of expertise to the point where "critical mass" occurs

Albeit Tin Knocking and Cabinet Making are very similar in methodology, yet distinctly different : )) the concept of mitigating the two, together, leads me to believe that those who put pencil to paper, never went to the job site : ))

I would offer a fresh idea in either withdrawing your bid or withdrawing your bid or withdrawing your bid, cuz anyone who gave you this opportunity is a also a tad naive ? imagination is great and profound but the practical applications of ideas is not easy.

Sub that part out ? Make all the drawings of what you want wrapped around a plywood slab, hope the drawing are right cuz steel, no matter what kind, is unforgiving, and give those drawings to a stainless steel shop, and hope those fit your cabinets ?…….,…it gets complicated, trust me <wink>

try and sell them a SS laminate ?


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## Grandpa

Don't forget to inquire about the minimum bend radius of the Stnls Stl. that all has to be factored in when making something like I believe you are describing.


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## fge

I am very confident everything will go together fine. I have a very good idea how I will ensure all goes together fine. I just need to ensure good glue contact is achieved but through some minor practice / test parts I am sure we will be able to determine if our contact glue will be successful.

I will check on the minimum bend radius of the 14g. I will talk to the metal shop about this.

I am also thinking about maybe using a liquid nail type of glue or a glue that has more open time. Contact cement I use has no open time and so when contact is made no adjustments can be made. Contact cement is reversible though which I like.


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