Grinding aluminium

**nobananas** · Sunday 21st October 2012, 17:52

I'm going to have a go at making the inlet manifold flow a bit better on the 850 R that I'm currently rebuilding (basically I'm just faffing about cleaning up the intersection between the manifold and the head to avoid doing any REAL work !). Last time I did anything like this was years ago using rotary grinding stones but there must be a quicker, easier way to remove aluminium. Anyone recommend anything, are the cheap diamond rotary rasps on ebay any good, would rotary wood rasps be up to it ?

**Dangerous Dave** · Sunday 21st October 2012, 18:01

I'm currently using a carbide burr to port my cylinder head. Got it from this guy off ebay

http://www.ebay.co.uk/itm/Long-Tungs...item5ae5765ac0

That one is a round nosed cylinder burr, the one I have is a round nose tree shape, but its one ebay at £100 and think it should be £10.

Have done two heads with it now, both volvo ones.

HTH

**nobananas** · Sunday 21st October 2012, 18:06

Thanks bomb, that's exactly the sort of thing I'm looking for.

**Dangerous Dave** · Sunday 21st October 2012, 18:09

There are some other 150mm long burrs on ebay, but they're more expensive and haven't had any problems with this one.

**M-R-P** · Sunday 21st October 2012, 18:27

Sounds like the sort of thing I got for Pedro a while back. What shape and quantity are you after? The ones I get are about 8 quid a pop and work very well on high-grade steel so ally won't be a problem.

**nobananas** · Sunday 21st October 2012, 18:34

Originally Posted by M-R-P

Sounds like the sort of thing I got for Pedro a while back. What shape and quantity are you after? The ones I get are about 8 quid a pop and work very well on high-grade steel so ally won't be a problem.

Just looking for fairly quick material removal, can clean up the surface afterwards with a dremel with drum sander attachment (which I have tried already, works nicely but is painfully slow !)

**M-R-P** · Sunday 21st October 2012, 18:40

The ones I can get are Buck and Hickman. They are very good at material removal (leading brand of high speed burr grinding bits) you'll probably only need a tree shaped and bull nosed bit. I'll check prices tomorrow if you like? Can get them to you by the middle of the week...

**Dangerous Dave** · Sunday 21st October 2012, 18:50

Nice one Martin

**oblark** · Sunday 21st October 2012, 18:56

Originally Posted by M-R-P

Sounds like the sort of thing I got for Pedro a while back. What shape and quantity are you after? The ones I get are about 8 quid a pop and work very well on high-grade steel so ally won't be a problem.

Just because they work well on steel doesn`t mean they will work on ally.

Ally is a softer than steel and is removed easier so it will clogg up steel cutters. Thats why you use a stone cutting disc to cut ally not a steel which will clogg up and explod !!!!!

**M-R-P** · Sunday 21st October 2012, 19:58

Explode?
I've used these on wood ally and steel. The cutter profile causes it to throw the swarf clear of the work surface and I've never had one clog, or become explosive.
Rotation speed is important with softer metals, no more than about 9000 rpm for ally.

**oblark** · Sunday 21st October 2012, 20:14

Originally Posted by M-R-P

Explode?
I've used these on wood ally and steel. The cutter profile causes it to throw the swarf clear of the work surface and I've never had one clog, or become explosive.
Rotation speed is important with softer metals, no more than about 9000 rpm for ally.

On "steel" cutting discs it should say "use on ferrous metals" and on "stone" discs it should say "use on non ferrous metals"

The reason for this because "steel" discs are made out of a different material than "stone" discs.

**M-R-P** · Sunday 21st October 2012, 20:17

Aaah, but we're talking burr grinding bits (big, industrial dremel bits).

You'll have trouble getting a 115 mm inox disk into an inlet manifold.

**nobananas** · Sunday 21st October 2012, 20:35

The ones I can get are Buck and Hickman. They are very good at material removal (leading brand of high speed burr grinding bits) you'll probably only need a tree shaped and bull nosed bit. I'll check prices tomorrow if you like? Can get them to you by the middle of the week...

That would be great. If you can price us up one of each posted to Cambridgeshire that would be a great help. Was going to pm you but my pm buttons gone, what's that all about !

**Dangerous Dave** · Sunday 21st October 2012, 23:04

Hi NB, you say theres a problem with your PM button? I'll have a look into it. How do you usually access PMs?

**nobananas** · Sunday 21st October 2012, 23:12

Originally Posted by bomb192uk

Hi NB, you say theres a problem with your PM button? I'll have a look into it. How do you usually access PMs?

Sorry bomb, been a bit of a numpty. I haven't pm'd anyone since the new site layout, I'm sure it used to have a 'pm this member' button on the left but found it now, you click on the members name ! (d'oh !)

**Dangerous Dave** · Sunday 21st October 2012, 23:14

LOL dude, no worries

**wegal** · Monday 22nd October 2012, 13:15

Quick safety tip... Aluminium dust is toxic as all hell, wear a dust mask and keep yourself safe.

**M-R-P** · Monday 22nd October 2012, 13:21

Originally Posted by wegal

Quick safety tip... Aluminium dust is toxic as all hell, wear a dust mask and keep yourself safe.

Just to add to the above, make sure it's a minimum of FFP2 specification mask.

**nobananas** · Monday 22nd October 2012, 13:30

That's probably why I've got a sore throat this morning !

**Harvey** · Monday 22nd October 2012, 21:10

Yes alu grinding is very bad for your health ,I have walked out of a number of workshops where a clown is grinding away but must say its always been the old boys that do it.
Also a bit of WD spray on the Burr cutter will slow down it clogging up.