How to cut brass discs with woodworking tools

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Phil Russell

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Very interesting thread. As I see it, there are two options: start from round bar and cut discs or start from flat plate and cut through the plate. Each has its pros and cons which I am sure you can appreciate.
If using round bar then I think that trying to cut all the way through with a mini lathe is not really on... 25mm is a long way. By all means use the lathe to scribe / cut a shallow recess around the bar to act as a guide, but then use a hacksaw to make the cut. If using plate, I advise the use of a pillar drill fitted with a good quality hole cutter. Obviously you will need to be able to clamp / secure the plate to the drill; I use a drill mounted vice. I have cut 20 and 25mm diameter discs in 6mm aluminium and 4mm mild steel using this method with no real problem.
Alternatively, ask a local machine shop if they could make them for you. I have no idea of the cost though.
A thought: do the discs need to be perfectly round? Or will you be finishing the outer diameter to fit? I ask because years ago I made a knife handle and used 6mm aluminium in part of it. I roughly cut a bit of 6mm plate and then finished it to fit by hand using grinder and filing.
Just thoughts.
Cheers, Phil
 

Snettymakes

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Some really great food for thought in these replies. Please don't be offended if I don't reply to them all though.

It sounds like you need to experiment with what you have (a variable speed wood lathe and find something to part them off with) rather than ask for the perfect solution on a forum, because you're doing something which is unusual.

Yes you're right, but honestly that's kinda what I was asking for in retrospect. A combination of hard information (tool X performs job Y, tool A is bad for job B etc) and anecdotes (I've tried x and it worked well/not) that I can apply to the context that I have (which would take pages upon pages to share) in order to come up with a tailored solution to my unique problem.
 

Fitzroy

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Some really great food for thought in these replies. Please don't be offended if I don't reply to them all though.



Yes you're right, but honestly that's kinda what I was asking for in retrospect. A combination of hard information (tool X performs job Y, tool A is bad for job B etc) and anecdotes (I've tried x and it worked well/not) that I can apply to the context that I have (which would take pages upon pages to share) in order to come up with a tailored solution to my unique problem.
Thinking out loud with a bunch of other people who have related experience, but unlikely to have ever made/completed precisely what I am working on, with the toolset I have available. Or that's how I use this place a lot of the time.

Another thought, from my huge experience (watching youtube and forgedinfire), it seems where a metal component is used to transition between other materials it is oversized and then ground/sanded flush. I'm currently making an item with two different woods and once piece is oversized so I can sand it back flush. I know I could not make two pieces sufficiently accurate that they would fit without this need.
 

Snettymakes

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A thought: do the discs need to be perfectly round? Or will you be finishing the outer diameter to fit?

Yes. 🤣

Actually it depends, either would work.

It all depends on boring the mortices in the handle and cane, if I can get those absolutely spot on (positioned and plumb), then I can use the pin to locate the transition absolutely perfectly in the middle of the cane. In that scenario a perfectly round disc that doesn't need any further finishing is preferable.

Alternatively then sloppy mortices and transition hole allow the pin to sit at a funny angle to accommodate imperfect mortices, gap fill with epoxy and then shape the outer transition and cane/handle together.

I have a feeling that wood is an insufficiently precise enough material to allow me to get this to fit together perfectly and I will end up going with sloppy fitting and shaping the glued up cane. I have turned a proof of concept of this approach. I need to refine the process somewhat as this proof of concept doesn't solve the "clamp the handle" problem, but I have a solution in mind for that. The transition for this proof of concept was very roughly shaped, which made turning it a bit of a nightmare, although doable. With that in mind, I'm aiming for "round but slightly oversized" so that the amount of material I need to remove is minimal.
 

sawdustandwax

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just a thought but you could use an angle grinder stand with a 1mm cut-off disc to cut the brass. May take some fettling to make a hold-down etc. A mini chop saw if you like. If you use pre-drilled bar stock as already mentioned, then you drill a hole in one part of the stick, turn a tenon on the other and voila, with some sanding.
 

Nelly111s

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Try looking at this and the two or three other related posts. James makes a mallet with a transition piece and cuts it and shapes in on a "wood" lathe. It may give some food for thought

Hashtagwoodworking
 

Sideways

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I was cutting up a steel tank for scrap today using an angle grinder and 5" x 1mm slitting disc. In passing, i snipped off a 25mm threaded brass pipe fitting. It cut through like butter, just 2 or 3 seconds. 25mm solid brass would have taken only a moment longer (but it is a nice grinder).
 

Tuna808

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Wondering how you’re fixing the bronze as a transition.
25mm washer have a thickness of about 3.4 mms.
Is it that critical that the thickness should be 5.
If you have a three jaw chuck on your wood lathe you could use a bolt or stud to clamp the together and soft solder them by sweating or silver solder with a low melting rod.
presumably the transition will probably have the be either thread or doweled in.
you could also try using a bolt ,hold it on the thread end on the chuck and make the hexagon into a circle….the thick can also be removed if you make or adapt your tool holder and use a tungsten carbide tipped tool.
These operations can be performed on a good quality drill is you get a bit creative with the clamping the drill to bench , tool holder etc
My first port of call would be to use brass which readily available and cheaper than bronze,and as already mentioned brass turns better and less messy.
secondly if the thickness is not critical to the structure and aesthetic you should use two sweated washer…. you can even epoxy them at a push..surely the focal point is not the transition piece….if it is accentuate the joint by adding a veneer or something similar.
good luck
 
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