removing mill scale from 1-1/4" stainless sch 40 pipe

belt sander?

Dan

Plating houses typically offer electropolishing of stainless. It improves surface finish, but most importantly, leaves the objects shiny.

Harold

Grant- since you are in the Puget Sound area, you are in luck. You take em up to Railmakers Inc. on Cedar Street in Everett. They will electropolish them. No muss, no fuss, no handwork. Railmakers Northwest Inc.

2944 Cedar Street Everett. 425-259-9236

Grant Erw> I have a friend, longtime local club member, whose business makes lots of

I called 'em. They say electropolishing stainless pipe doesn't remove mill scale - it just gives you shiny scale.

I was kind of thinking about a 6x48" Scotchbrite maroon belt on a belt sander, and running the pipe on two wheeled pipe supports, one on each end, so the pipe presents exactly 90 degrees to the belt. With a gloved hand, resist the turning of the pipe and also feed the pipe longitudinally. The ends you'd do by moving both supports to one side of the sander.

I found a nifty tool:

but it's spendy beyond a reasonable limit.

GWE

Ries wrote:

I doubt you really have scale, just the pitted finish left after the scale has been removed.

Dynabrade makes, or used to make, something similar, but it's not going to be any less expensive.

I used to be in the marine hardware business, so have a good idea of what you're up against. I wouldn't even consider polishing the tube myself. Either find a shop with a centerless belt grinder that will do it for you, or buy the material polished from the mill. There are (or at least used to be) plenty of small tube mills that would polish material to order, even in very small quantities. For the most common tubing (1" x .083") I'd buy a couple thousand feet at a time, but I can recall ordering as little as 100 feet of stuff we weren't likely to need again.

Here's a centerless belt grinder...

This appears to be the reincarnation of the place I used to buy from... Ned Simmons

I am a bit confused- I have literally tons of stainless polished every year, and I have never heard of the electropolish finish not being good enough. It is true that the finish will be a shinier version of whatever you give them- so if you give them a factory mill finish, it will be a shiny version of that, and if you hot texture the pipe first, it will be a shiny version of that.

What is the problem with shiny mill scale? It isnt coming off, it wont rust, and it looks a lot better than the unshiny kind.

If you want mechanical polishing, there is a place in the south end that has the machines- I did a bunch of work on the Baseball Stadium and I had the pipe I used on that mechanically polished. Cant remember the name of the place- but I think both Alaskan Copper and Seattle Boilerworks recommended them.

If you really want to do it yourself, you can get scotchbrite sanding belts for any belt sander, and go at it. Klingspor will make em to order to fit any size- I sometimes run em on my old Makita 1 1/8" x 21" belt sander.

Personally, I would order prepolished tube or pipe if thats what you want- it wont cost much more, and it will save an enormous amount of work. Alaskan should carry it.

Railmakers actually makes boat railings out of shiny stainless steel- thats their main business. They buy several sizes of tube, not pipe, prepolished and wrapped in plastic, by the bundle.

Ok. Quick and dirty to make (not so quick but definitely dirty to use).

For one batch of hand rails I made I ended up with rougher pipe than I wanted. So I made a wheel that goes on my angle grinder that allows me to run a 1" x 42" sanding belt inside out on the pipe. It takes skill and concentration to run it properly without breaking the belt, or wearing the edges but if you can pay attention to what you're doing it works well (example is that I could make a belt to a complete 21' section of pipe with no problem in fact if not much had to be taken off then it would last several before it quit cutting, my helpers on the other hand had trouble making a belt last for 5' of pipe).

The wheel is simply a piece of 1 1/2" stock that is drilled and tapped for the 5/8" spindle of the grinder. I pushed a piece of hose over it to provide friction to drive the belt. I then tacked two 1 and

1/4" washers onto each side to prevent the belt from coming off (I'd previously turned a couple of shoulders on the stock to accommodate the washers). Worked well for that job and a couple of other minor jobs One important thing is the crown the piece of hose to help hold the belt in center. What eats the belt up is holding the drive wheel at a angle which causes it to rub the washers till they rip a tear into the belt. Also pulling to hard would cause a belt break. But when used properly it worked wonders taking off the globby paint they'd put on the pipe.

Grant Erwin wrote: My

A long, long time ago I worked at a factory that made large industrial washing machines for animal cages, hospital gurneys and the like. The machines were all stainless. The polishing was done with 10" - 12" buffing wheels charged with coarse abrasive. The power for the buffing wheels was provided by a flexable shaft driven by an electric motor (maybe 5 HP?) mounted in casters on the floor.

Kevin Gallimore