Cutting seats with Neway cutters - 1st experience

[Nut124]

I ordered Neway cutters for my Fiat twincam project. 45/30 and 75/15. A 60 cutter is coming today.

I cut the seats and the top cuts plus some 75 in the throat. Waiting for the 60 cutter to reduce seat width. I had to cut quite a bit going to valves that are 1-1.5mm bigger than stock and the OEM seat cuts are small to start with.

I am impressed with these tools. I find that they cut true and concentric. 7 of 8 seats were perfect. EX4 had a little bit concentricity error and I had to touch it up with the 45 cutter. Could have been a spec of debris in the guide.

I did this at the kitchen table. Used no fluid. Used a vacuum cleaner to remove cutting residue every few minutes. I had purchased a magnifying head set from Amazon for $20, which was handy at 2.5x to see the detail and take measurements.

I almost screwed up on the first valve cutting too much with the 75. Lucked out just barely. The 75 cuts a lot faster because the angle multiplies cutter pressure - gotta watch out.

Took me perhaps 5-6 hrs over two days, going slow and checking often.










The seats need the 60 cut to narrow seat width.

[stealth]

I'm curious to see what others say.. I used them on a Ford 8BA Flathead with good luck.

I actually ran the cutter backwards after cutting to burnish the finish and remove slight chatter marks... Not sure if that was correct, but seemed to work … all with a light touch.

Like you said, I used a magnifying glass and light to inspect, along with a final lapping with compound.

and really, the ol" flatty never had it so good....

[rp930]

I used them for years on German imports, worked great. One place I worked for had an electric drive for it which was really nice.

[BCjohnny]

Need to be careful running carbide cutters in reverse, some are easy to chip, but the Neway ones with their angled serations are probably more resistant than most

Don't on the whole rate them, they'll get the job done in a fashion, more of a diy tool, but they're ok for topping and tailing seats if you mostly use stones and get into the aluminium on non-ferrous heads

OP ..... didn't it maybe occur to you to practice on the other 'scrap' head you have first ?

[Nut124]

Don't on the whole rate them, they'll get the job done in a fashion, more of a diy tool, but they're ok for topping and tailing seats if you mostly use stones and get into the aluminium on non-ferrous heads

OP ..... didn't it maybe occur to you to practice on the other 'scrap' head you have first ?

I agree they are for DIY jobs. Too slow for commercial jobs perhaps unless it's a touch up job. I had to cut a lot.

I did practice on another head a bit but the throat in it was already cut a lot and I failed to get a feeling for the speed of the 75 cutter. The other head I had had no guides but would have had untouched seats.

[dannobee]

They are slow, but they do a pretty decent job otherwise. As a DIY'er, at least you're forced to sneak up on it and not ruin the seat like when using stones.

For me, I sometimes use them when flow testing and can flip the head over and try different widths or angles pretty quickly.

[BillK]

I use them almost every day. That is all I have had for the 30 years I have been in business other than the Serdi type cutters for my TCM 25 seat and guide machine. I use the Neways for just about every stock valve job that I do. I do have the stands and the electric drive setup. I find them very fast. You absolutely have to keep sharp cutters. They are a little pricy but when they get dull they dont work worth a crap.

I did a pair of Subaru heads today that came in with a bunch of bent valves. All of the guides were good. It probably took me less than 10 minutes to touch up all (16) of the seats. I can typically do a pair of V-8 heads in about the same amount of time. I prefer them to the 3 angle setup because I think the 3 angle deal ends up sinking the seat more than really needed.

I only use the TCM if I am cutting for larger valves, replacing seats etc. Also if I am putting guides in a head because they almost never go in perfectly concentric to the seat and the Neway cutters do not do well with that.

I could add more but basically I think they do a great job.

[AC sports]

Now that you've cut the seats, lap a couple of valves and check concentricity again. I always had issues with this. I put it down to the expandable pilot though. Tapered are better.

[4vpc]

Check your seats with some blue to check accuracy.

[Nut124]

Now that you've cut the seats, lap a couple of valves and check concentricity again. I always had issues with this. I put it down to the expandable pilot though. Tapered are better.

The tapered pilots felt very solid.

After cutting, I checked the seats w layout fluid using the method explained by Jim at Neway. I think it is in their manual as well. I assume you all know how it goes but I'll put it in here anyway. The goal is to examine the valve to seat contact while turning the valve as little as possible.

1. Mark valve with marker for 12 o'clock position.
2. With dry layout fluid on seat and valve, apply some fine compound.
3. Put the valve on seat with the mark at 12.
4. With light pressure turn the valve with a stick but only from 11 to 1, not all the way around.
5. Examine seat and valve for contact.
6 . If seat and valve have contact all the way around, then either both are true and concentric, or both are off exactly in the same direction and same amount.
7. Repeat the test in the 6 o'clock position. If the second test is good, then any chance of bent valve or non-concentric seat is eliminated.

Like I said, 7 of 8 valves/seats were prefect. EX4 seat was off and needed a very light cut.