Adapter for table saw arbor?

[DennisCA]

I read something in an old post here about making a sort of slip-over adapter for a smaller arbor so you'd be able to mount 30mm blades without using inserts. I got a 20mm arbor and while fiddling with the inserts isn't that bad I wonder if the idea is practical if I wanted to get a longer arbor though? I might as well turn it into a 30mm one then too.

What I am thinking is a round 30mm piece with internal threads that simply screws onto the current arbor, this is then the new bigger arbor. Sounds pretty simple to me. But I am not sure if that would work or not, maybe I am overlooking something? Maybe there's a risk of the whole arbor coming loose (perhaps it's no bigger than the risk of the nut coming loose during regular operation) or something else I've overlooked?

Is there perhaps someone who does this kind of job routinely or would I have to start looking for local machinists?

 

[wizard]

Why would you want a longer arbour?

 

[DennisCA]

Because of something that causes lots of derails on this forum and that I wanted to avoid talking about for that reason.

Let's just think of Norm for a hint.

 

[wizard]

So you do not want any help then

 

[DennisCA]

I just wanted to avoid the dado debate... There, happy? Dado, dado, dado, I said it three times and now we're done for!

 

[wizard]

well turnip you then

 

[DennisCA]

I answered all your questions despite your unpleasant tone and all you got in response is an insult. Well pineapple you, you foul language alert.

 

[wizard]

:lol:

 

[Myfordman]

It is a job for a machinist really as it is vital the adaptor is perfectly concentric with the original shaft.
The last thing you need is a wobble with a full stack mounted.
A good solid saw with plenty of power helps too.
Also helpful if there is no brake or only a gentle one on the spindle.

Nought wrong with a dado head sensibly used despite what most here will tell you.

MM

 

[wizard]

How can he be helped if he unwilling to say what he is trying to do, there is no way i am going to give advice on something that may be dangerous. Then there is the cost, is the motor of the right HP, is the shaft a motor shaft, if so it may be a problem. Is he planning on doing it himself? Hi might just as well have asked how long is a piece of string. I am willing to help where i can if the person wants help but not when i get a reply like that.

 

[DennisCA]

There's practically only one reason one would want a longer arbor and I suspect you know that, I preferred to just leave it unsaid because I've seen the drama that has erupted in the past on this board in those discussions. But I acquiesced and told you, in a joking manner to indicate there was no hard feelings despite this stubbornness, and then you told me what I assume was "f*** you".





As for relevant information to anyone who cares, the motor is ~3.3HP and 3-phase, the arbor is not directly connected to the motor shaft but uses a drive belt, the saw is an industrial machine from 1976 and given the time it takes to spin down I don't think it has a break.

If this where feasible I'd have a machinist do it, be nice if there was someone who had done it before and knew what it was for or about, then I wouldn't have to go hunting some local machinist (don't know anyone suitable locally), I wouldn't have issues handling such a thing online with a UK or german machinist or some other country. Of course it'd depend on what it would cost, too expensive and I might as well just keep saving for a router and build a table.

The idea I had though was if one would make it internally threaded so it'd screw onto the arbor the same way you screw on the nut, from what I saw in the older threads (and it was hard to visualize what people where talking about there) they had some different setup to achieve a diameter increase. I think my idea sounded simpler and the increase from 20 to 30mm in diameter ought to leave the arbor flange with a useful rim still, but it'd new need flanges to support the blades.

 

[RogerP]

It can be done but will need someone with a lathe and expertise. He/she might well need the shaft assemble to ensure it's concentric when fitted. It would cost quite a bit. As you inferred it's probably better to get a cheap router and make a simple table.

I've never seen such an item for sale.

 

[MickCheese]

I have no experience or expertise but just a thought, would it be possible to remake the whole assembly with a larger shaft? After all it's not part of the motor. Or is that just a stupid idea and likely to be very expensive?

I cannot help thinking that a sleeve over the existing shaft could be asking for trouble.

Mick

 

[wizard]

Motor is big enough no problem there, all you need to do now is cut the existing thread to the full extent of the shaft, it should be a left hand thread, the extinction will have to be drilled and taped in a lathe again using a left hand thread. simples

 

[seaco]

I could possibly do this for you but I'd need some measurements and the thread size you have... I think to be on the safe side it would be an idea to add a grub screw that went through into your original arbor for added security...

 

[DennisCA]

I was hoping to avoid that to make any modification reversible. Could one use loctite or something instead, then it ought to be very firmly there. Perhaps red loctite which would require heating the part to get it off again.

That is also why I was thinking the internal threaded part would only be as long as the threaded part of the arbor, the rest would be smooth. I also don't want to be taking the arbor off the machine, that veers into too much work/effort to be worth it.

 

[wizard]

You seem to know what you want so just take it to a local engineer and get a quote simples, or have you nothing better to do and you just need someone to talk to.

 

[monkeybiter]

Maybe the OP is wondering if anyone has done a similar mod, to benefit from theyre experience.

Or maybe just someone pleasant to talk to.

 

[wizard]

Maybe he should go and buy a lathe then he can do it just as he wants it :wink:

 

[DennisCA]

Is there something in the water in cornwall.