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Gallery, Projects and General => The Design Shop => Topic started by: John Rudd on February 25, 2013, 03:35:37 PM

Title: Valve seat cutter
Post by: John Rudd on February 25, 2013, 03:35:37 PM
I need to make a valve seat cutter but have come across a slight problem.......... :doh:

My original intent was to make the cutter from Silver Steel, profiled and hardened to suit...

I started making a mock up from some EN1a 1" diameter bar but found it was a tad too small...The SS needs to be ideally in the region of 1-1/4" but I cant source any.......

Back to drawing board.... :dremel:

EN1a is in plentiful supply but I'm not sure it can be hardened to perform as a cutter..

So, what else can I use along with the EN1a bar to make a cutter?  was thinking along the lines of some sort of carbide insert...but not sure how to go about this....?

Just to add the diameter of the valves are around the 7/8" mark...if this helps? and its for a small Villiers engine I'm renovating...
Title: Re: Valve seat cutter
Post by: philf on February 25, 2013, 04:09:27 PM
John,

Silver Steel is equivalent to O1 tool steel or gauge plate. O1 is readily obtainable in most sizes.

EN1A can be case hardened but isn't suitable for a cutting tool.

Cheers.

Phil.
Title: Re: Valve seat cutter
Post by: Bluechip on February 25, 2013, 05:05:19 PM

The SS needs to be ideally in the region of 1-1/4" but I cant source any.......


13" lengths are here. Download the supplies catalogue link.
 
Page 9.
 
http://www.livesteammodels.co.uk/suppliescat.html (http://www.livesteammodels.co.uk/suppliescat.html)
 
Better to sit down first though ....£30 +vat ish .... not what you might call 'freeware'  :(
 
Dave BC
Title: Re: Valve seat cutter
Post by: sbwhart on February 25, 2013, 05:11:49 PM
If you're cutting the seat in something soft like ally or brass you will get away with case hardening.

Stew
Title: Re: Valve seat cutter
Post by: awemawson on February 25, 2013, 05:32:43 PM
Make a suitable EN1A cutter, but cut a pocket in it for an indexable insert
Title: Re: Valve seat cutter
Post by: vtsteam on February 25, 2013, 08:51:41 PM
I think a fairly thick old automobile leaf spring under my shed might wake up in the morning to find a bit of its length missing in such a circumstance.  :dremel:
Title: Re: Valve seat cutter
Post by: John Rudd on February 26, 2013, 06:53:02 AM
Make a suitable EN1A cutter, but cut a pocket in it for an indexable insert

This is the alternative I'm considering after seeing a countersinking cutter on a Chinese tool website..... :dremel:

Thanks for the ideas guys... :thumbup:
Title: Re: Valve seat cutter
Post by: philf on February 26, 2013, 08:26:08 AM
Make a suitable EN1A cutter, but cut a pocket in it for an indexable insert

This is the alternative I'm considering after seeing a countersinking cutter on a Chinese tool website..... :dremel:

Thanks for the ideas guys... :thumbup:

John,

You may probably already have considered this but there's one more thing to bear in mind - If you are going to use the tool either hand driven or via a power tool rather than in a milling or drilling machine you need to set a stop (possibly on the shaft which goes through the valve guide) so that it not only limits the depth of cut but, particularly when using a single insert cutter, to prevent you ending up with a spiral valve seat with a step where the cutter stops.

Cheers.

Phil.
Title: Re: Valve seat cutter
Post by: Jo on February 26, 2013, 09:17:07 AM
Case hardened MS worked very well on my Cast Iron  R&B gas engine head.  :thumbup:
 
Jo
Title: Re: Valve seat cutter
Post by: John Rudd on February 26, 2013, 10:46:53 AM
Case hardened MS worked very well on my Cast Iron  R&B gas engine head.  :thumbup:
 
Jo

Jo do you have any fabrication details  on your cutter please?

Saves 're-inventing the wheel' .....a couple of photos wouldl be great too if you have any ..

cheers

John
Title: Re: Valve seat cutter
Post by: NeoTech on March 02, 2013, 11:37:51 AM
(http://www.miratool.ch/admin/upload/186_pro.jpg)
(http://www.miratool.ch/admin/upload/155_pro.jpg)
Title: Re: Valve seat cutter
Post by: rotorhead on March 02, 2013, 06:42:16 PM
Hi John,

A very good supply can be found here.----- http://www.lawson-his.co.uk/stubs-r080a-silver-steel-imperial-1-1-4-x-p44342

That's just for 1-1/4" @ £18

Chris
Title: Re: Valve seat cutter
Post by: OKTomT on March 03, 2013, 01:50:25 PM
John this is what I use its made by Neway. Its hand operated and very well.
(http://i1323.photobucket.com/albums/u592/Toms1909engine/IMG_1012_zps2df31c09.jpg)
Title: Re: Valve seat cutter
Post by: John Rudd on March 03, 2013, 03:12:35 PM
John this is what I use its made by Neway. Its hand operated and very well.

Yeah ,I've seen the Neway offerings but they are very expensive.............Not quite within my budget..  :coffee:
Title: Re: Valve seat cutter
Post by: vtsteam on March 03, 2013, 03:42:41 PM
Don't know how big your valves are but maybe this would be helpful to at least look at.

http://www.homemodelenginemachinist.com/f31/4-cylinder-ohv-engine-new-cylinder-head-work-progress-5529/index4.html#post62611