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Discussion Starter #1
Yep it happened...I caught an edge on some green wood and snapped the end off the banjo tool rest.......ruined my turning session but that's all.
Now I have to decide to repair the banjo or upgrade.
I'm going to take it to my local metal fabricator and see if he can repair it.
Do you guys have a source of banjos that might be compatible with my old delta rockwell?
What do I need to know to make them compatible?

Please help...I'm bummin':sad:
 

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The banjo is the piece that holds the tool rest and attaches to the lathe bed. Did you breat this, or the actual tool rest?
 

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anything on Ebay?

http://www.ebay.com/sch/i.html?_nkw=lathe+banjo
I've had good luck brazing cast iron. I broke the entire idler pulley and support off my metal cut off saw and brazed it back on, after positioning and securing it, ground it down and painted it. Can't tell anything ever happened. A good metal shop will fix it, no problems, look/ask for the "old" guy who knows how. :laughing: bill
 

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1) I'm REALLY glad that the damage was limited to just the banjo

2) can you post photos of the broken part(s) ... I have an old Dunlap lathe which I was trying to figure out what I should do with ... maybe the banjo would fit your lathe ways?
 

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Discussion Starter #6
http://www.ebay.com/sch/i.html?_nkw=lathe+banjo
I've had good luck brazing cast iron. I broke the entire idler pulley and support off my metal cut off saw and brazed it back on, after positioning and securing it, ground it down and painted it. Can't tell anything ever happened. A good metal shop will fix it, no problems, look/ask for the "old" guy who knows how. :laughing: bill
Thanks,
That answers my first question....Metal shop.....I'm looking for someone as old as I am

2nd..
Is it worth it to repair or should I consider updating the banjo to a more versatile rest and attachments.

Thanks
Tom
 

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repair or update..

I'd repair it. It will take an hour or so of shop time if it's a simple break which can be V grooved and brazed. It may also be able to be reinforced with a sleeve if it's the vertical part. The wings are a different story and are under a lot of force from the securing bolt.
A weld/braze may nor hold up...pictures would help or a description of the exact "condition" for further online surgical advice.... :laughing:

If there is an upgrade that offers more features maybe that's the way to go. I donno? I've seen some with dual posts for longer work..spindles. etc. You can always fix AND get a new one. :blink: bill
 

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Discussion Starter #9
I'd repair it. It will take an hour or so of shop time if it's a simple break which can be V grooved and brazed. It may also be able to be reinforced with a sleeve if it's the vertical part. The wings are a different story and are under a lot of force from the securing bolt.
A weld/braze may nor hold up...pictures would help or a description of the exact "condition" for further online surgical advice.... :laughing:
Dear Dr Bill
Here's my problem..........

I started with this




....and ended up with this



Repair or upgrade?????
 

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Discussion Starter #11
Ah ... I forgot ... when I did the fix w/ oak, it was on a tube-rail lathe with a two-part banjo and the bottom part broke and was easily replaced w/ oak. No help to you at all.
That's okay...I appreciate the interest.

....besides...I was trying to picture that....oak?:blink:
 

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I you can add any additional material up close to the post to reinforce the intersection, then brazing may work. Keep in mind the intersection is the weakest part of the rest.

What I would do: I would saw off the post and braze it to a new steel plate with the slot cut into it with a metal cutting bandsaw from the post end. Or use two separate bars welded together to form the proper slot width. Or make the whole thing out of steel and bore a round to accept the tool rest. Don't get me started here.... I never throw away a broken tool unless I've come to hate it for some reason. :furious: bill

This one looks close: http://www.ebay.com/itm/SEARS-Craftsman-tool-rest-mounting-BRACKET-BANJO-f-wood-working-Lathe-/250907702523?pt=LH_DefaultDomain_0&hash=item3a6b43b4fb

 

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Is this a cast iron piece?

If so this article might help if you have the tools. Otherwise, as has been said, just get a new one.

Welding Cast Iron
There are many different cast irons, many of which are totally unweldable as they will crack when you heat them. Fortunately by far the most common and the most frequently used for car components (bell housings etc) is called Nodular or SG Iron.

Nodular Cast Iron is modified by adding an innoculant just before casting (Magnesium or Cerium) which changes the shape of the graphite flakes from pointed (stress raiser) to spheroidal (hence SG or Spheroidal Graphite). This grade welds relatively easily but there is a knack to it:

  • Keep it cool not cold (around 50°C is a good indicator).
  • Avoid long runs, 25mm max.
  • Balance the welds across the joint - start at one end and then weld a bit at the opposite end.
  • Use specialist Nickel Iron electrodes that run on low current.
  • After every weld peen the bead (tap it lightly with the round part of a ball pein hammer). When preparing the joint grind out the surface to be welded so you get a full penetration weld.
  • If it’s a crack repair, grind out the crack, drill the ends to stop it propagating, and allow to cool to room temperature after every weld.
Preheat or Not?

To preheat effectively you need to heat the casting to 500°C (I wouldn’t fancy trying to weld it when its that hot). Also the preheat has to be applied consistently, no hot spots or cold spots. Castings are usually variable section thickness so the thick bits need to be the same temperature as the thin bits. Really the only way to effectively preheat is to use an oven / furnace which makes it very difficult. Therefore the cool method is the most widely used.

The weld metal filler specifically designed for cast iron is either pure nickel or nickel-iron. It is possible to use mild steel but it will pick up carbon from the cast iron and become very hard and brittle which makes it crack sensitive and very difficult to grind back to shape. Nickel blocks the migration of carbon therefore it doesn’t become brittle, even the nickel-iron alloy, so it can be machined and it retains its elasticity.

The electrode coatings used are designed to promote operation at low currents and consist mainly of graphite which is an excellent electrical conductor. Why is this type of coating only used on cast iron rods? For exactly the same reason as mentioned in the earlier paragraph. Graphite would add carbon to, and em-brittle, virtually any steel but not nickel rich alloys.
 

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Discussion Starter #15
After a few calls in my area, I am headed down to see "Butch the Banjo Guy".:thumbsup:
He has a specialty welding & fabrication shop in the next town over.
When I called him he said " oh sure...bring in on in. You're not the first to bring one of these in for repair''
.......awesome!!!!
This might be fun.... or expensive......or both.
I'll keep you posted
 

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take some pictures!

Show how he does it if he'll let you. Tell him his shop will be famous on the web. :laughing: Good Luck.
 

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Show how he does it if he'll let you. Tell him his shop will be famous on the web. :laughing: Good Luck.
Good idea....I'll bring my camera and get right in his way and say " look this way, and smile for the forum, BUTCH!!!!:laughing:
 

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Tig

I see that its cast iron, so see if your fabricator has a TIG welder. If so, good, as TIG welding of cast iron is the way to go its fast and reliable.
All you do is knock the flux off some cast iron arc welding rods and use them as filler for the TIG. As for gas the standard argon gas used for stainless will do fine. You can get awya with little of no pre-heat of the banjo

I have done this on my own cast toolrest a couple of times and for others around my neck of the woods, never had problem with any of the joints
 

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where's my table saw?
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Now that's what I was talking about!

You might want to consider a slightly larger washer under the locking bolt, but HD is right! I actually think you could make it with 2 solid bars and the bored round,with a cross bolt at the far end with a spacer, rather than slotting a wide bar. At least that's the way I would do it, because I'd want a clean slot on the inside, and I don't have a vertical mill. (it's on the list however) :yes: bill


 
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