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  • IDEA #3: fix the crack with regular brass braze rod then use the silver solder to get the new hub into the handle -- the difference is about 400 deg F

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    • Originally posted by nickel-city-fab View Post
      EDIT: on second thought you *might* get away with grinding out the crack a bit and using the same grade of paste in the whole job, all in one go. Remember its gonna flow in the direction you aim the heat.
      I ordered the medium silver solder last week thinking that would be a good compromise, its on its way. I was thinking dish out the inside of the crack a bit and let the whole thing flow in. I believe they welded it with nickel rod because its hard as hell, they did the other handle as well and it will not machine off. I was concerned that if the crack is left 'untacked' before the silver it might open up/expand so I thought maybe just a tack weld on the outside to keep it stable.

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      • Originally posted by vectorwarbirds View Post

        I ordered the medium silver solder last week thinking that would be a good compromise, its on its way. I was thinking dish out the inside of the crack a bit and let the whole thing flow in. I believe they welded it with nickel rod because its hard as hell, they did the other handle as well and it will not machine off. I was concerned that if the crack is left 'untacked' before the silver it might open up/expand so I thought maybe just a tack weld on the outside to keep it stable.
        Yep you're probably right. Not all nickel rod is machinable. The only cure I know of is to anneal the entire thing. Usually not worth doing. Nickel 99 rod is the machinable kind but it still needs careful post-heat/ insulation.

        Not sure if it'll expand enough to matter, but tacking it on the edge couldn't hurt. Worst thing that can happen is another crack where the tack restrains it.

        Believe it or not, I'm using Roach killer for flux nowadays (Harris bug killer from Ace Hardware) because it's 99% pure boric acid powder. It's 8 bucks a pound, can't beat that. Exact same chemical used in the commercial fluxes.

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        • BTW here's a good Clickspring video showing the use of the silver solder paste starting about 5 minutes in: https://www.youtube.com/watch?v=R9m4...beOli&index=20

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          • First if anyone has any ideas why I cannot post a regular 'new topic' post (the button doesn't work but all others do) please let me know, otherwise I have to keep going back here.

            Second please advise on how you would handle this bronze bushing replacement. The shaft is offset to the housing as you can see from the old bushing. I only have a three jaw chuck on the SB. All the housing does is hold this bushing so I wonder if it would be better to center up the bushing and move the mounting holes or try and turn the bushing offset either in the mill or lathe with spacers. The old bushing is quite cobbled up as it looks like they used a hand grinder to get it to fit. So three things have to happen with an offset bushing in my mind, the housing has to bolt down, the five screws have to line up and the shaft has to go on. Don't know if I can pull that off accurately. Ideas please? Click image for larger version

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            • ….So, make another offset bushing or slot the screw holes in the housing?
              I don't think I understand what your question is.

              -D
              DZER

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              • Originally posted by Doozer View Post
                ….So, make another offset bushing or slot the screw holes in the housing?
                I don't think I understand what your question is.

                -D
                Doozer have you been drinking again or too much North Carolina BBQ? That's my question, which would seem more fitting under the circumstances. Is making a new bushing and trying to keep three fitting items in check better than slotting and in addition is that kind of one-off off set bushing normal in machine tools? I haven't seen this before but what do I know I have been drinking...

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                • You could try putting the old bush in your chuck and measure the eccencitricity of the bore. Then shim one of the jaws to get the same runout on the od. Machine the od first. If there is a risk of the jaws distorting the bush,then chuck up a longer solid bar with about 1/4" more projecting from the chuck than the finished length and machine the id blind
                  Last edited by old mart; 09-24-2020, 03:04 PM.

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                  • I'm having a hard time believing that Monarch would intentionally do an offset like that unless it was somehow needed for operation. Either way would work though -- slot out the holes in the cover, or use shim spacers like Old Mart says. The only problem with slotting out the holes is that it tends to look and feel very hack-ish unless you can make some custom fasteners to cover the gaps.

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                    • Originally posted by old mart View Post
                      You could try putting the old bush in your chuck and measure the eccencitricity of the bore. Then shim one of the jaws to get the same runout on the od. Machine the od first. If there is a risk of the jaws distorting the bush,then chuck up a longer solid bar with about 1/4" more projecting from the chuck than the finished length and machine the id blind
                      I ordered twice the length of bushing that I need so your advice gives me food for thought. Thanks I think that will work.

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                      • Originally posted by nickel-city-fab View Post
                        I'm having a hard time believing that Monarch would intentionally do an offset like that unless it was somehow needed for operation. Either way would work though -- slot out the holes in the cover, or use shim spacers like Old Mart says. The only problem with slotting out the holes is that it tends to look and feel very hack-ish unless you can make some custom fasteners to cover the gaps.
                        One of the reasons I posted this. I too find it hard to believe they would do that but I can't figure out how it got that way unless this cover somehow got replaced. Even then I would thing they would be pretty standard at the factory. Thanks for your input.

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                        • Ok, I understand what's going on now. That is for the leadscrew reverse it looks like. I'd say another offset bushing to match would be the answer. A 4 jaw is really the device for the job but if you don't got one, you don't got one. A shim on the 3 jaw will work.

                          One way you can get the bushing clocked right is to go ahead and mount the cover, then use a slip fit bushing with some bearing retainer. That will allow you to clock it in place. As Doozer has cautioned though, it sets up fast, so you need to have some thing to push it in and be ready.

                          I'd make a few practice pieces in aluminum or plastic to test your method. Slip fits, installed dry. Then you'll have the assurance for the real deal.
                          21" Royersford Excelsior CamelBack Drillpress Restoration
                          1943 Sidney 16x54 Lathe Restoration

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                          • I am beginning to see.
                            So if the bushing offset is in the horizontal plane only,
                            then I would say slotting the holes in the plate would be a good fix.
                            If the bushing is also offset in the vertical plane, then you would also
                            either need to shim the cover (with shim stock) or mill some off
                            the covers flange.
                            Maybe it is one or both situations, but I do think making a custom offset
                            bushing is kinda hack, and not what was originally made.
                            But yes BBQ and drinking to excess both.

                            -D
                            DZER

                            Comment


                            • Originally posted by The Metal Butcher View Post
                              Ok, I understand what's going on now. That is for the leadscrew reverse it looks like. I'd say another offset bushing to match would be the answer. A 4 jaw is really the device for the job but if you don't got one, you don't got one. A shim on the 3 jaw will work.

                              One way you can get the bushing clocked right is to go ahead and mount the cover, then use a slip fit bushing with some bearing retainer. That will allow you to clock it in place. As Doozer has cautioned though, it sets up fast, so you need to have some thing to push it in and be ready.

                              I'd make a few practice pieces in aluminum or plastic to test your method. Slip fits, installed dry. Then you'll have the assurance for the real deal.
                              I am also beginning to see the light. Here is the old bushing, they cut slots in the rear so they could do exactly what yall are saying, they installed and turned it to fit. But I think not a good job as you can see inside. They also drilled a set screw hole to fix in place as in 1941 they didn't have superglue
                              I suspect this was done long after 41 or the factory. I swear virtually every single part on this ol gal has been f**ked up. Its now turned into an endless chase. If I take one thing off the thing under it is hacked. The entire lead screw housing ear was cracked and had to be brazed up and extra bolts added. Not one thing I have taken off is OK. Pity. I thank you for the thoughts as they
                              bring light to an otherwise dark project. I'll make aluminum trials per TMB to make sure all is well before the final bushing. I hate to do this offset as Doozer and I feel the same, a crappy hack.


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                              • Get yourself a pot of Loctite 620, it is a sleeve and bearing fit product which has a slow cure. Loctite 638 or 601 are good, but I have felt them going off while I was assembling the joint, which can be worrying.

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