making drill chuck adapter - is brass a dumb idea?

[disco_monkey79]

Hi, and happy new year

As per another thread, I recently bought a multico K1 morticer, which normally uses different-sized adapters to hold the auger shank via a grub screw. It only came with one such adapter, and I was unable to find any more online.

I found an adapter to fit the 5/8 motor shaft with 1/2 x 20 unf thread, so I have fitted a drill chuck- so far, so good. However, it is diecast steel, so I am concerned it may crack with prolonged use, especially with the torque of boring tougher hardwoods.

I'd therefore like to make a more robust version. Would a hefty cylinder of brass be suitable? It'd be easier for me to drill to size and tap - but I don't want to bother if it's going to trash itself as well.

If brass is a sensible idea, any ideas on where to source a blank, and what such a thing would be called? I'd need a cylinder about 50mm long, with an OD of circa 1" - 1.5". If these come with a bore hole already, that would be handy as I could just bore it out to the required size.

If brass is a dumb idea, then the same question applies to steel _ I have looked at pipe, but couldn't find anything close to the dimensions I'd want.

Many thanks

 

[Phill05]

I could let you have either Brass (easy to cut and will not break up) or Steel (harder to cut) or Stainless steel (extra hard to cut) and could bore a guide hole for you, PM your sizes and e-mail if any good to you.

 

[niall Y]

I thought , in your title you were referring to the collars that fit round the square chisels. I had a few of these turned for me to suit my collection of chisels. However I realise you were referring to the part holding the auger shaft. I don't see why a Jacobs chuck isn't suitable - after all, it is fitted as standard in Sedgwick mortisers.

A colleague of mine used to have a massive floor-standing mortiser, and the method of holding the auger shaft was as you have described - with a grub-screw, but the same connection was used for all sizes of auger. This gave rise to a certain amount of whip at the top of the auger shaft, though it did not affect the performance of the machine.
This slight missalignment would have annoyed me, but I believe it is standard for certain makes of mortiser

Edit. just realised, you were referring to the suitability of your drill-chuck, adapter. Don't see why it shouldn't perform well enough, cast steel isn't cast iron. And it has obviously been made to perform a function

 

[disco_monkey79]

I thought , in your title you were referring to the collars that fit round the square chisels. I had a few of these turned for me to suit my collection of chisels. However I realise you were referring to the part holding the auger shaft. I don't see why a Jacobs chuck isn't suitable - after all, it is fitted as standard in Sedgwick mortisers.

A colleague of mine used to have a massive floor-standing mortiser, and the method of holding the auger shaft was as you have described - with a grub-screw, but the same connection was used for all sizes of auger. This gave rise to a certain amount of whip at the top of the auger shaft, though it did not affect the performance of the machine.
This slight missalignment would have annoyed me, but I believe it is standard for certain makes of mortiser

Edit. just realised, you were referring to the suitability of your drill-chuck, adapter. Don't see why it shouldn't perform well enough, cast steel isn't cast iron. And it has obviously been made to perform a function

Hi

Yes I am probably being a worrier over nothing, but everything I make is always massively overengineered! And it looks quite flimsy compared to the whacking great lump of steel that was the original part!

Ta

 

[disco_monkey79]

I could let you have either Brass (easy to cut and will not break up) or Steel (harder to cut) or Stainless steel (extra hard to cut) and could bore a guide hole for you, PM your sizes and e-mail if any good to you.

Hi, that's great, thank you. I will get some proper dimensions and come back to you for brass.

Thanks again

 

[ChaiLatte]

I think this is what you want:

https://www.ebay.co.uk/itm/372700496392
You could use the photos as a guide to determine proportions of the one you make.

 

[disco_monkey79]

I could let you have either Brass (easy to cut and will not break up) or Steel (harder to cut) or Stainless steel (extra hard to cut) and could bore a guide hole for you, PM your sizes and e-mail if any good to you.

Hi

I was chatting to a friend about this, who then gave me a piece, so I am sorted (until I screw it up!), but I really appreciate the thought. Thanks again.