advice please - remove over weld on inside of tube

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I'm a hobbiest that you would probably consider a beginning metalworker.I'm building a heavy duty outfeed roller stand.  It is basically a single column quadpod (as opposed to tripod) with the column consisting of two DOM tubes, one which telescopes inside the other (for height adjustment). The inner tube supports a roller.  The walls of both tubes are 3/16". The ID of the outer tube is  1.375".Before fabrication I test fit the DOM tubes and they telescoped really nice with almost no play, but once I welded the quadpod legs to the outer tube the fit was a no go.  I thought it was weld distortion, so I turned down the inner tube about 1/100th.  Still no go.  I found the REAL problem was that I over penetrated on one or two of the quadpod leg welds.   I have a shallow bumps of metal on the inside of the tube that I would like to remove.  The worst is about the size and shape of a flake of oatmeal and they exist about a foot from the end of the tube.How the heck could I get this out?Do I need a adjustable reamer set?  If so, how do I reach that deep?(BTW, I welded the legs on to the outer tube without the inner tube inserted, so I guess there was nothing to prevent the shrinkage of the outer tube.  But how was I supposed to do it?  If I welded with the inner tube inserted I may have ended up bonding them forever.)
Reply:Originally Posted by kajongaBefore fabrication I test fit the DOM tubes and they telescoped really nice with almost no play, but once I welded the quadpod legs to the outer tube the fit was a no go.  I thought it was weld distortion, so I turned down the inner tube about 1/100th.  Do I need a adjustable reamer set?  If so, how do I reach that deep?
Reply:" If I welded with the inner tube inserted I may have ended up bonding them forever"You would have....... you over penetrated on your DOM tube and you would have welded them together. Concentric tubes and welding is tricky, heat is NOT your friend, use minimal welding, don't run long beads, many short ones are better than a nice long warping your tube bead.Your fix is get a 1.375 ( 1 3/8 ) drill bit with a 1/2 shank but a drill bit extension on it ( look at your local tool store electricians use these quite a bit to get into stuff ).Chuck up your bit in the extension use your drill and go to town. I would use my old Milwauke with the handle as big bits hurt if they get stuck ( and they always seem to ) with hand drills.Another way to get it is if you have a die grinder put an extension shaft ( or flex ) and run a wheel inside it to get your burr. If you have a lathe you could chuck up your pipe put the bit in the tailstop, but you would have to work morse taper extensions and tailpost usually only have about 4-5 inches of stroke.Option 1 or 3 is how I would do it because I have the tools, how precision I wanted it would be my determiining factor.Last edited by fredschrom; 12-29-2011 at 11:01 PM.Reason: spelling fix
Reply:DSW has it right.  I'd use a 1" sanding drum on an extension.  The I.D. at the weld can be a little oversize.  You have plenty of engagement.  http://www.husqvarna.com/au/construc...-1-1-4-f-bits/Dynasty 300DXSmith He/Ar gas mixerMM350PHobart Handler 120Smith LW7, MW5, AW1A
Reply:Can you get a 1-3/8" hole saw to slide into the pipe? If so put it on a long extension and run it through. You may need to "sacrafice" the hole saw by removing the rake on the outside teeth if it's too tight. Once you get started the saw body will act as a pilot as you clean up the inside.Another option would be to push/pull/press a 1-3/8" die though the pipe. Your die could be as simple as a few inches of shafting with one end cut at a slight angle, this angle becomes your cutting face. Provide the flash isn't too much it will slice right through it.
Reply:forhire beat me through the holesaw trickso +1 on the hole saw
Reply:Maybe its time to redo the design where the affected area will not be used or in the way or redo the part. The problem isn't just where the two welds passed through but having the four welds altogether causing the tube to shrink. This going by what you said about how tight the fit was before the welding was done. This happened to me on something I built for my bro when I welded a nut to a piece of tube that way a bolt could be used as stop. The weld shrank the tube where the other tube would not pass through and luckily my bro had a brake hone that he used to fix it.
Reply:" Can you get a 1-3/8" hole saw to slide into the pipe"Boy if that binds up its going to be a man eater.Another way is to use a cylinder hone if you can find one that small.
Reply:You might also try a small cylinder hone.  Since we're not talking precision, you should be able to lap the lumps, as it were.  I've used a sawzall to file and sand inside shapes before.  I've used Forhire's idea with great success too.  The other thing you might try is to turn a wood dowel to fit into the bore turn the end down to fit a drill, cut a slot in it and wrap sandpaper around it.  Make sure the tube is secure.  Really secure. Keep us posted.Contrary to popular opinion, I do NOT have a pet turkey that craps molten steel.  It's a goose.
Reply:Originally Posted by fredschromAnother way is to use a cylinder hone if you can find one that small.
Reply:kajonga,Forgot to ask. How did you get melt through on 3/16" thick material and what process were you using?
Reply:big hammer? sometimes the best answer "might" be the simplest lol
Reply:Originally Posted by MilitiaMetalsbig hammer? sometimes the best answer "might" be the simplest lol
Reply:Originally Posted by Jay OAtleast list a couple of techniques that are going to help along with your suggestion, maybe their is something we're missing?
Reply:Find a piece of solid shaft the same as the I.D." and drive it through with a BFH, or press
Reply:if you have access to a lathe, try to find an adjustable reamertackleexperts.comwww.necessityjigs.comhttps://www.facebook.com/groups/mach...dingequipment/
Reply:" Here's a better bet: Take an 18" piece of, say, 3/8" round steel. Slit it on a bandsaw for a couple of inches. Insert a strip of sand paper, maybe 36 grit, into the slot with about a foot of it dangling. Insert the non-slotted end of the rod into the drill. Slowly spin the drill to wind the sandpaper into a nice roll. Jam 'er in the hole, and LET IT RIP! Does that make sense? I've used them many times but can't find a picture."Makes perfect sense and its a good idea. If you have a 1 inch sanding drum run that up on a extension rod and have at it, that would work also.A lot of ways to fix this, iits all about what tool or equipment you have.
Reply:I've welded short extensions on these before. Terribly slow but they do work. Not one of my everyday go to tools but when nothing else is available they get it done. I save the worn down bigger ones just for those odd sizes like this situation the OP has. http://www.lehighvalleyabrasives.com...els/CategoriesGreat for rough shaping or reshaping gun stocks BTW. Especially dry hard walnut. One of these in a die grinder and feather away. Let your eyes be the guide, proceed very slowly. You can't put dust back on."The things that will destroy America are prosperity at any price, peace at any price, safety first instead of duty first, the love of soft living and the get rich quick theory of life." -Theodore Roosevelt
Reply:Originally Posted by kajongaHow the heck could I get this out?
Reply:Now that we've spent hundreds on buying fancy bits and reamers.........How about just cutting out the section, lopping off the legs, bevel and weld the two pieces back together, with the inner pipe inside. This time taking it easy on the welding. Reattach the legs, again, taking it easy on the welds. Pictures of the unit would help. Or if you don't think you can weld the to pieces together without making a seam, put a sleeve over the joint and weld that. I really think that a drill or hole saw on an extension, using a good size drill, is just going to get twisted apart. Just my two bits. But yeah, pictures are worth a thousand words.200amp Air Liquide MIG, Hypertherm Plasma, Harris torches, Optrel helmet, Makita angle grinders, Pre-China Delta chop saw and belt sander, Miller leathers, shop made jigs etc, North- welders backpack.