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chevynut
09-11-2015, 03:52 PM
I decided to start doing a little work on my chassis construction and thought I should finish up my gas tank and get it mounted onto the frame and get it plumbed in.

I have gone over the tank with fine scotchbrite pads on my die grinder to remove the mill finish and the scratches from sanding the welds, etc. I still have to pressure-test the tank before polishing in case I have to weld some more.

Can anyone offer any advice or methods for polishing a stainless tank? I have a buffer on a stand but I don't think it will work as the tank is too cumbersome and heavy to polish that way, and the shaft isn't even long enough. What are the alternatives? I have the stainless buffing compound. Do I need to sand the tank with fine paper first? It's pretty smooth with the scotchbrite treatment. Would a 7" angle grinder with a buffing pad work or is that too slow? I hate to think I have to use the die grinder.

I plan to add a drain bung and a vent bung, both stainless steel. I didn't think I wanted a tank drain but have decided it's a good idea, even if just to get any water or bad gas out of the tank. I decided a vent would be a good idea too after reading about all the problems filling these cars up with gas and noting the 57 tanks have a vent for a good reason ;). I plan to weld in a 1/4" NPT bung for the drain, and a 3/8" NPT bung for the vent. I think those should be large enough. I will weld another 3/8" bung into the filler neck somewhere neat the top.

Rick_L
09-11-2015, 04:13 PM
This may be one of those things that you may want to farm out. It will be a lot of work. For alternatives to the stationary buffer, look at the velocity on the outside diameter of the stationary buffing wheel vs. the velocity on the pad you'd use on the grinder. Also you'd probably do well to buy or figure out how to mount buffing wheels of the style you'd use on the stationary buffer to use on the grinder. I think you will need to start off with something "rougher" than a wool pad, and then progress to that. Places that sell buffing supplies may have something that fits this description.

All that said, the best way to do it would be to have a buffer like the plating shop uses on bumpers. I'd also guess that two people working the tank against a big stationary buffer is much more efficient than a portable grinder with a buffing wheel.

Never done this, just speculating from what I know about other buffing stuff. Please post what you do, as I have the same dilemma (perhaps including leaving mine as is).

As for the vent, they all need a vent. The 55-56 vent in the cap neck should be adequate for the electric pump. The 57 bypass tube/"vent" is for filling the tank.

chevynut
09-11-2015, 04:26 PM
As for the vent, they all need a vent. The 55-56 vent in the cap neck should be adequate for the electric pump. The 57 bypass tube/"vent" is for filling the tank.

Yes Rick I know they need a vent and was going to use a vented cap, but I was trying to address the filling issue. I've read about lots of guys spilling gas all over their 55s and 56s when filling them up. Do you think the 3/8" NPT is big enough, or should I go to 1/2"? I think I have both size SS bungs. I'll probably just use some rubber fuel hose.

There's a local guy who does stainless polishing and I may ask him what he'd charge to polish the tank or get some advice from him on how to do it. I may go ahead and try the 90 degree grinder I have and see what it does. The bigger problem is the weight and bulkiness of the tank...it's a lot for one person to handle. Maybe I can help him do it. ;)

bobbybelair
09-11-2015, 04:41 PM
It's not the venting that causes the splashback. The angle of the filler neck is shallow so if you get to the automatic shutoff when filling, it's gonna splash. You have to slow down and try to figure out where you are when filling. I bundle up a wad of the paper most gas stations have and stuff it under the filler neck so it absorbs any of it, but I've gotten pretty good at figuring out the fill.

MP&C
09-11-2015, 04:43 PM
Instead of trying to manhandle the tank onto a pedestal buffer, get a wool pad for your hand held paint buffer and go to town.... with the tank sitting on a table.

chevynut
09-11-2015, 04:53 PM
Here's what the tank looks like after the scotchbrite treatment. It works really well for removing scratches, but leaves a lot of swirls. I'm going to hit it with some 1200 grit paper I have and see what happens.

Bobby, it was my understanding that the problem with the 55-56 fillers is that as gas goes into the tank, the air it displaces has to come out and it comes up the filler neck to the atmosphere. As it comes up it pushes gas up with it.

Robert, hope you're right about the grinder. My grinder is a higher speed one than a paint buffer...it's a Makita 7" angle grinder. I think I have a buffing pad for it. I'll give it a try and see if it works.

http://www.trifivechevys.com/attachment.php?attachmentid=4918&stc=1

chevynut
09-11-2015, 04:56 PM
Weird...thread stats say 1 view and 5 replies. Where does this stuff come from anyhow?

bobbybelair
09-11-2015, 05:08 PM
Not me, I see 6 replies, 12 views.

chevynut
09-11-2015, 05:16 PM
Now it's 7 replies, 12 views. I even refreshed the page before a couple of times and it still only said 1 view. Counters must be on daylight savings time. ;)

rustay56
09-11-2015, 05:22 PM
Lazlo, I'm with Rick on this one, farm that job out. Polishing is just like painting (but less forgiving).Sand,sand then sand some more.start polishing only to find a scratch wash everything down and start sanding again,and at the end of the day your covered in black residue and you can look forward to doing it all again tomorrow.let the professionals do it,and keep going on your other projects. Also the cost of buying all the products (and time,cause you could be doing a paid job ie chassis work) for you to do the job should be deducted from the professional guy's price and that's to true cost,then it doesn't seem so expensive.And remember ,it only hurts if you pay cash,if you use credit card it doesn't hurt at all :)

Regards Andrew.

Rick_L
09-11-2015, 05:47 PM
Rustay56 makes a good point. For you to do it successfully and somewhat efficiently you'll have to spend a bunch on materials, and you'll still have to work your ass off.

If you insist on doing it yourself, do it just like a paint job - use sandpaper in fine then finer grits, use every step in the grit sizes available - and use sandpaper as long as possible up to 3000 and higher grit. Think about what it takes to do stainless trim, most of that stuff that's in good shape still requires a lot of work and those pieces are tiny compared to your tank. The big difference between paint and polishing metal is that the metal can stand far more wheel speed but needs that to make progress at all.

chevynut
09-11-2015, 10:20 PM
I understand what you guys are saying, but I think I have the materials to do the job so I'll give it a shot. I'll go ahead and call Rodney and see if he wants to take on the job, but last time I talked to him he said he was booked over a year out on stainless trim work. So that's a consideration if I want to get anything done. If I can do it myself I might as well....I like the challenge, but if it gets to be too much I'll try to farm it out. I'm at the point that I want to make progress regardless of the cost.

chevynut
09-28-2015, 06:00 PM
Well I think I screwed up a bit. Earlier I took my "fine" scotchbrite pads and went over my entire tank. I shouldn't have done that. It worked to remove sanding scratches at the welds, but I shouldn't have done the whole tank. I bought some "fine" pads at Goodguys and they leave a lot nicer finish. So now I have to go over the whole thing again to remove the scratches from the first pads, which apparently were "medium".

I also picked up a wool pad for my 7" angle grinder for $8 and I have a bunch of stainless and aluminum buffing compounds from Caswell. I can't seem to get the compound to do much with the grinder. I wonder why.

Once I get all the scratches taken care of I plan to take the tank to Rodney at Stainless Trim Works locally and get some advice from him. Surely he's done this before. ;)

Rick_L
09-28-2015, 06:28 PM
Take money when you take the tank. Problem solved.

Custer55
09-28-2015, 07:59 PM
On my 55 you really have to fill it slowly and have a good idea how full the tank is or it will spill gas out on the side of the car. I pull the nozzle back so I can see down the filler neck to see the gas when I'm close to full. It's a real pain.
On the stainless polishing I remember spending countless hours polishing the trim on my 55. It looks great when it's done, but it takes lots of time and effort.
Brian

chevynut
09-29-2015, 08:10 AM
Take money when you take the tank. Problem solved.

No Rick, it's not that simple. ;)

I talked to Rodney at Stainless Trim Works last night and he says he's so busy he can't take on any work. He says he's booked out a year. He also says he doesn't really do work like this and focuses on trim restoration. I don't know of anyone else who does this stuff locally and I'm NOT shipping it.

I've searched the web and checked as far away as Denver to see if anyone can do this for me and found one possibility that I plan to call today. By the time I search for someone to do it, call them for an estimate and to discuss what I want, take it down and pick it back up, I'll have at least 8 hours invested.

Have you checked into the cost down there? How much would you pay to have this done?

I asked Rodney for advice on doing it myself and he said it wasn't easy and was very time consuming. He also said it was hard to get a uniform finish on flat surfaces by hand. He said not to try using a buffing wheel on a buffer for that reason, and that it's almost impossible for one guy to do it.

Rick_L
09-29-2015, 10:44 AM
I don't have a local source. If I was looking for one, I'd approach a local shop that does chrome and other polishing, primarily for motorcycle stuff. And they might not want a fuel tank because of the size.

chevynut
09-29-2015, 09:15 PM
I talked to a guy at Mile High Polishing in Denver today and send him some pics of my tank. He didn't act too excited to do it, so I guess we'll see if he quotes it.

In the meantime I've been re-considering polishing it. I've gone over a lot of it with the fine Scotchbrite pads on my die grinder, and it's removing the scratches from the medium Scotchbrite. Wow was it ever a mistake to do that whole tank with the medium stuff. :(

Anyhow, I'm considering doing more of a very fine "brushed" or "semi-gloss" finish rather than a full mirror polish. The tank has a few welds on the bottom where I welded internal baffles to it, and there's some slight warpage. A mirror finish will just amplify those defects. My son suggested I get a scotchbrite flap wheel and go over it to make the brushed finish.

Rodney also warned me about trying to polish my stainless plumbing lines, saying it's really dangerous to do on a buffer. He suggested just sanding them by hand with 600 grit and calling it good. I may try some 600 grit on the tank too, after I smooth it all with the fine scotchbrite and see how it looks.

Any thoughts?

Custer55
09-30-2015, 10:08 AM
I sure it would look nice with a brushed finish as well. You could try it on a scrap piece or the top of the tank that won't show first to see how you like the finish.
I did the aluminum face plate of my council with a brushed finish and it looks good to me.

http://www.trifivechevys.com/attachment.php?attachmentid=5037&stc=1http://www.trifivechevys.com/attachment.php?attachmentid=5038&stc=1

chevynut
09-30-2015, 12:32 PM
Still nothing from Mile High Polishing. I really don't think he wants to do it.

I've worked on this thing for about 6 hours now and I think I have a process down that I want to use. Will post some pics as I get further along.

chevynut
10-01-2015, 12:02 PM
Still nothing from Mile High Polishing. This is why I typically do this stuff myself. I get sick of all the runaround you get from these guys, and the risk of paying too much for shoddy work in the end.

Some time after I started my Nomad build I needed to have some rear tubs made. I spent quite a bit of time building a wooden buck to the shape I wanted. I just wanted someone to form the tubs, and I'd trim them to fit my car. I talked to a guy at a rod shop a couple hours from me and he said he'd do it. A year later nothing had been done so I told him to just trash the buck and I was going to do it myself. I finished them and I think I did as good or better job than I would have gotten from him. Since then NOBODY has done anything on my car but me, that is until I paid a guy to paint the frame.

I've spent about 3 more hours this morning working on it and all the scratches and defects have been removed and everything is ready for final polishing. I figure I have about 11 hours in it so far, part of which was removing the scratches from the medium scotchbrite. I did use it again this morning on some sanding marks I found, but it was work out some and gave a finer finish. I estimate 20 hours by the time I'm finished.

chevynut
10-03-2015, 08:29 AM
I never did hear back from Mile High Polishing so I just kept working on my tank. I got the hole drilled for the tank drain bung and I'm trying to figure out how I want to do the vent. Here's the progress on polishing so far. Like Rodney said, this is not as easy as it seems. It's really hard to get a uniform shine. I polished the top first so I could get a process that worked. Nobody will ever see that part once the body is on. I also polished the fuel pump unit cover just cuz. ;)


http://www.trifivechevys.com/attachment.php?attachmentid=5051&stc=1

http://www.trifivechevys.com/attachment.php?attachmentid=5052&stc=1

I think I'm pushing 16-18 hours on this already and only have the top fully polished. The rest of it is smooth down to the final polishing which is going to take a few more hours. :eek:

WagonCrazy
10-03-2015, 07:54 PM
You're fully committed now. Keep going...:(

chevynut
10-05-2015, 05:46 PM
Now that I'm 80% of the way there I finally got an estimate from Mile High Polishing after I asked if they got my pics. I doubt I would have heard anything if I hadn't sent another text message after sending my pics as he requested.

I told him I had it all down to a very fine Scotchbrite finish and it just needed final finishing, and he could see that in the pics. He replied "from the looks of it were going to need to surface all the grinding off, then polish". I don't know what "surface all the grinding off" means, but this joker is sounding just like Jose at Ogden Chrome. There is no "grinding" to be taken off. It was already so smooth that sanding with 600 grit takes it to the next level, and 1200 takes it to almost a mirror finish after that. In fact if you keep sanding with 600 dry, it really shines.

He said it would run $350-500. You know where it would end up. Would you pay that?

Rick_L
10-05-2015, 06:16 PM
Well there's reflections in your photos, and to me that means you've made nice progress. And it also means that if you send it out, you will pay for the work you've already done. So keep going and quit when you're satisfied.

What I'd like to see on the forum is a single post reviewing what you did in terms of methods, materials, and hours - that would be very helpful to me and others. Not that you haven't reported it, but a summary would be great.

I have a Rock Valley tank that I need to decide what to do with, if anything.

chevynut
10-24-2015, 04:04 PM
Well I sure learned a lot polishing this tank.....it's a lot of work :p. Here's some things I learned....

* Mill finish stainless is actually pretty smooth from the mill.
* If you build one yourself, see if you can get polished stainless to start with.
* If you want a pre-made polished tank, see if the manufacturer offers one polished for a reasonable price adder.
* If you can get this done for $300-500 PAY for it. ;)
* Polishing is much more about sanding than it is buffing.

If you still want to do it yourself, don't make the same mistake I did. I was given some advice to start with 220 paper, go to 320, then 600 and keep sanding until it's smooth. 600 is nowhere near fine enough to get a smooth mirror finish. In fact, 3000 isn't fine enough for a mirror finish. When I started polishing I hit the welded areas with what I thought was fine scotchbrite disc on my die grinder, but it was medium. That would have been fine if I only hit the sanding marks from smoothing the welds. But I went over the entire tank with it which was a big mistake. Then I used a fine scotchbrite disc and hit it again . This was a few hours work alone. I thought I was getting somewhere so I attacked the whole tank with 320 on a DA dry. Then I went to 600 on a DA wet. That got it where I could see myself in the tank, bit I could still see scratches from the scotchbrite and probably the 320. So I kept sanding....and sanding...and sanding. I tried buffing too soon and it did virtually nothing. So I had to go back to sanding. After the 600 grit I went to 1200 on a DA. Then I hand sanded with 2000 wet. Then I tried 2500 wet. I finally ordered some 3000 for my DA and used that. It got the tank to a fairly good shine, but it was blotchy. So I kept sanding some more until I finally hit it with a small buffing wheel on my die grinder and green compound. It left some "brushed" marks in the right light so I hit that with another buffing wheel with white compound. That was better, but it still had very fine scratches....so I finished it off with Meguiars's Diamond Cut paint polishing compound and a polisher which helped quite a bit I don't recommend this trial-and-error process though. Here's what I'd recommend at this point:

* Assess what you have to start with by using 600 grit and no coarser on a DA sander. The paper dulls fairly quickly so you need quite a bit.
* If you have defects that you want to smooth out, go to a coarser grit only on the defects and get back to 600. A fine scotchbrite pad on a die grinder works well to remove this coarser stuff.
* Once you finish everything with 600, go to 1200 grit and keep going until polished. If there are scratches, go back and smooth them with slightly coarser grit and go back up.
* Finish off sanding with 3000 grit. This might be good enough for you, but if you want a mirror finish you have to go further.
* Buff with green buffing compound using some sort of buffer.
* If it's not a mirror finish, use some paint polishing compound like Meguiar's Diamond Cut to blend all the very fine scratches.

Sue, you can start with coarse paper and go up from there, but it adds a TON more work to do it that way. I would only go there if you really need to. You can stop at around 2000 grit and sand by hand to get a very fine brushed look that hides a lot of defects if you want to. I thought about doing that but decide to keep working. I think I ended up atover 40 hours in this tank, at least twice what I thought it would take.

Here's some progress pics and what my tank looks like finished. It's not perfect, but it's pretty dang good. If I look closely I can still see some faded scratches from the 320 and probably the medium scotchbrite pads.

http://www.trifivechevys.com/attachment.php?attachmentid=5141&stc=1

http://www.trifivechevys.com/attachment.php?attachmentid=5142&stc=1

http://www.trifivechevys.com/attachment.php?attachmentid=5143&stc=1

http://www.trifivechevys.com/attachment.php?attachmentid=5144&stc=1

http://www.trifivechevys.com/attachment.php?attachmentid=5145&stc=1

Rick_L
10-24-2015, 06:06 PM
Sounds like your best tip is not to sand with a grit that's too coarse so that you're effectively going backwards. Makes sense to me.

chevynut
10-24-2015, 07:16 PM
Yes Rick, I think starting with the finest grit paper you can is the best way to go to save time. I got to thinking near the end of this that maybe a diamond grinding pad would work great on this stuff. I had a granite countertop installed and the installers had a pad that they put onto a 4" grinder to smooth the granite at seams. Wish I'd thought of it sooner. :)

The first set below even includes 6000 grit.


http://www.ebay.com/itm/Wet-Dry-Diamond-Polishing-Pads-4-Inch-Set-Kit-For-Granite-Concrete-Marble-Polish-/311428555269?_trksid=p2141725.m3641.l6368

http://www.homedepot.com/p/Archer-USA-4-in-3000-Grit-Wet-Diamond-Polishing-Pad-for-Stone-WPP04-B-3000/204584893?cm_mmc=Shopping|THD|G|0|G-BASE-PLA-D25T-PowerTools|&gclid=CMaw2cDG3MgCFUyAaQodgL8Eog&gclsrc=aw.ds

http://www.toolskitchen.com/4-dry-polishing-pads-set-of-8-pcs.html?gclid=CK_LmN_G3MgCFQmoaQodrjwL5g

Bow tie downunder
12-16-2015, 02:03 PM
Hi Would you be interested in selling that tank and making a new one out ot mirror finish stainless.Iwould be interested in purchasing the tank
Mick

chevynut
12-16-2015, 08:22 PM
Mick, I'm not interested in selling the tank after all that work! ;)

Bow tie downunder
12-17-2015, 12:33 AM
Mick, I'm not interested in selling the tank after all that work! ;)
I can understand why ,I hadn't seen the finished product .It looks great ,beautiful job

Bow tie downunder
12-17-2015, 02:15 PM
Would you be interested I in making a fuel tank for me

chevynut
12-17-2015, 02:19 PM
Mick, sorry I'm not interested in getting into the gas tank business. Surely you could find someone down there to make one for you. I would have to charge you $5000 for as much work as I have in mine. LOL! :) :)

What exactly are you looking for? Do you need a custom tank or would one from Rick's or Tanks, Inc, work?

I just had a customer ask me to blast and prime his frame and bend all the fuel and brake lines. I really don't get into that kind of stuff, since I want to put out frames not finished, rolling chassis. I told him that I could have it blasted for him and shoot a coat of primer if he paid me to do it. I think I'm going to try the Clausen "All-U-Need" on it, which I wish I'd done on my frame.

Bow tie downunder
12-17-2015, 03:36 PM
I'm after a stainless tank with pump and fittings ,no polishing .Canadian hot rods make one for 57 chev for $ 1450 but they won't ship out of Canada

chevynut
12-17-2015, 05:31 PM
Rick's tank is around $1200 and Tanks, Inc has some stainless ones for $575 with pump and sender.

Bow tie downunder
12-17-2015, 09:43 PM
Thanks I

Florida 57
01-26-2018, 09:35 PM
A couple of products to consider when polishing with out the benefit of a stand polisher.Busch Polish sells pads that attach to a Rotary buffer and the use of Emery compound. For light to heavy scratches such as what may be found in stainless trim, Camel Grinding Wheels sell a pad for your hand held grinder.The key to this pad is light pressure until you are familiar with how your stainless reacts, otherwise you leave gouges that will have to be sanded out.The gouges show up with the finer grit sanding process.The pad is not a finishing pad but removes heavy scratching.Depending on outcome, 320-400-600, the polishing wheel.(Sissel or cutting then medium or finishing wheel with compound)
https://www.buschshineproducts.com/buffing-techniques.html

Apparently I will need to learn how to downsize pics.The sample work with the pad was just a blur in the pics.

Florida 57
01-26-2018, 09:41 PM
Pics. of test spot with CGW soft pad.