Routering Cast Iron

[JonnyW]

Please forgive me if this subject has been hammered to death.

I own a Scheppach Preciso 4 table saw with the cast iron table top. It's a lovely saw, which I wanted partly for the stacking dado blade capability.

It does everything I need it to do and more, however a major bug bear of mine is the track that Scheppach has designed for the mitre gauge.

It’s a horrible inverted T track which you slide your gauge into (and there it stays until you slide it completely out). I can’t remember the dimensions, but the top of the slot is approx. 6 or 8 mm opening to your standard 19mm (if I remember right).

I absolutely hate it; it means you can’t buy third party mitre gauges like the Incra, which use a standard 19mm mitre bar. Or any other jig that comes with your standard mitre bar.

I’ve used aluminium flat bar for homemade jigs over the years, and they work fine.

My question is - has anyone used a router to remove the top of the t-slot to open it up into a standard 19mm slot?

I have seen a video of a guy using a standard router bit on cast iron, and it seems to cut it easily enough. Or is this fake news? or a complete nut job?

Just wondering if anyone has tried this?

Thanks

Jonny

 

[pcb1962]

You might get away with it, if your cast iron is soft and consistent. The problem is that cast iron often contains hard spots, either a result of uneven cooling, or due to inclusions. If you hit a hard spot at best it might only destroy your router bit. I would take the top to a machine shop to do the job properly on a milling machine.

 

[Phil Pascoe]

How about the 1/2" shank end mill the Pete Maddex uses in his router? I haven't the link but iirc it was only about £12 on evilbay.

 

[TFrench]

Sounds like my kity's aluminium table. I just used the original bar and drilled and tapped it to take the UJK mitre fence system. Minimum of fuss!
I'd never risk using a router on cast, there's a reason milling machines were invented!

 

[custard]

Just wondering if anyone has tried this?

They don't make safety glasses thick enough for me to ever try this!

 

[Droogs]

Think you would want more than just glasses, I'd probably want to wear an EOD balistics suit as well. like this one:
http://www.protechsales.com/product/olympia-bomb-suit/

 

[dynax]

Think you would want more than just glasses, I'd probably want to wear an EOD balistics suit as well. like this one:
http://www.protechsales.com/product/olympia-bomb-suit/

Damn, i was looking at similar earlier, but thought was taking the Pxxx so i didn't bother posting :shock:

 

[chiokli]

You could fit an appropriately sized 1/2" or 12mm end mill into a router, but the biggest hurdle would be the lack of rigidity in the setup. I don't think there would ever be a way worth your time to set up guide rails to move the router along solidly, a feed system consistent enough for a constant chip load on the flutes, and a router with a slow enough speed setting (maybe 2000rpm?) to get a clean cut on cast iron. I think taking the top to a machine shop with a big Bridgeport would be the best situation.

 

[JonnyW]

Thank you for the replies - including the PPE shopping list .

I had to ask the quetion as I know nowt about it. If it was doable and easy, then worth a try.

I must admit he did make it look pretty easy on his video - but hey, it could a fake video!!

https://www.youtube.com/watch?v=xxQO6hILZLY

I think I'll stick to my aluminium guide rails that I screw onto jigs. At a minium it'll save me buying all that PPE.

Cheers again.

Jonny

 

[pcb1962]

There's an outfit called Ocean Kinetics very local to you who have the machinery to do the job properly for you, might be worth having a word with them.

 

[wallace]

I have cut ali and brass on the saw bench and the router table with good results. That video you linked to is legit and if done properly it can be done.

 

[chiokli]

Though, having seen Cosmas Bauer do it, and I believe that he actually did, it might work?

https://youtu.be/Urz57RVC15A

He does preface it with the type of cast iron his table is made from.

 

[JonnyW]

Thanks all for the replies and video.

I did consider speaking to Ocean Kinetics.

Jonny

 

[JonnyW]

Though, having seen Cosmas Bauer do it, and I believe that he actually did, it might work?

https://youtu.be/Urz57RVC15A

He does preface it with the type of cast iron his table is made from.

That's a really interesting video.

 

[galleywood]

In the video relatively little material is removed as it is a dovetail shaped slot.
From what you said you would have to enlarge your slot from 6 or 8mm to 19mm - far too much (even progressively) to do safely or accurately in terms of straightness and width.
A job for a milling machine I think.

 

[wallace]

Wadkin were making high speed routers to cut cast iron engine blocks 70 years ago

 

[JonnyW]

My track slot is an inverted T. It's a 10.5mm openning at the top with a 21mm openning at the bottom. The material I would be removing is very little and is probably less than what Cosmas Bauer removed.

Jonny

 

[JonnyW]

As you can see, not a great quantity of material has to be removed, so I think the router bit and router could handle it.

 

[galleywood]

Do let us all know how you get on.

 

[JonnyW]

I will do. I’ll post some photos.

It may not be able to router depending on the cast, so I’ll try a few mm test area in a location that won’t bother me if it can’t be done.