Valve seat cutters
Discussion
I need to know what cutters are used. The seats I have cut are 45 degrees but I want to order a cutter that opens up the throat as it is now too small. I have been offered a 30 or a 70 degree but dont know which to order. These are advertised on ebay from India with a diameter. Is this the larger or smaller?
This is a very specialised job and is usually done by experienced machinists in a dedicated mill where everything can be aligned carefully. Even there it takes skill to cut the seat accurately. If you don't even know what the valve seat angle is, this suggests you aren't experienced in this area. In that case I'd advise you to get the seats cut by a specialist. This is not a DIY job.
Consequence of getting it wrong could be a new head.
I too would advise getting it professionally done.
If you put your location you might get some recommendations.
In the Leicester area I would suggest Neyta Motor Engineers. Been there for years & I've used them several times for various engine work - incl head skims, valvework & the odd sheared bolt (the last being an inlet manifold bolt on a RRC V8 head) - & not had a problem.
I too would advise getting it professionally done.
If you put your location you might get some recommendations.
In the Leicester area I would suggest Neyta Motor Engineers. Been there for years & I've used them several times for various engine work - incl head skims, valvework & the odd sheared bolt (the last being an inlet manifold bolt on a RRC V8 head) - & not had a problem.
Edited by paintman on Sunday 25th November 12:28
It is for a 1929 Austin and it is not the first time I have done valve seats as I even made new inserts from cast iron bar. Previously I made a spotfacing cutter to bore for the seats. I have a 45 degree cutter but need to open the throat of the new inserts to match the valve better. Is the cutter usually a 70 degree one for opening the throat?
Humph7ey said:
I spent most of my working life as a machinist and toolmaker but while I can still cut a thread on a lathe it is sometimes difficult to understand angles. Something to do with age.
Just reading this thread I would like to apologise for all the patronising bds on here . Most these people couldn’t change a CV boot . Good on you for having a go. my dads old mate used to work on a mill he could make pretty much anything from metal . He’s rebuilt loads of engines quiet a few old BSA ‘s of late . Gassing Station | Home Mechanics | Top of Page | What's New | My Stuff