Cheap valve seat cutters-tips/experiences?

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I grabbed a cheap set of valve seat cutters but the quality is a little less than expected and the pilot isn't tapered which leads to it being a tiny bit loose. Does anyone have any experiences with these or have tips on how to atleast get the pilot centered and where it won't wiggle? It's a 5.5mm pilot but it's not tapered out to 5.8mm or whatever to ensure a tight fit.

Any help or suggestions would be much appreciated.
 
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Here's a picture of the components in the valve seat cutter kit.
 

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vpd66

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I've never used or seen those style cutters. They look like import copies of Neway style cutters. They don't look like there made to very tight tolerances. I own Neway cutters and I also have the electric driven Souix stone style cutters. I prefer the Souix stone style cutters. The valve guide pilots are the key to getting a concentric valve seat. Cutting valve seats is a real delicate process. Its very easy to remove to much material and and up with a very sunk valve seat witch kills flow. A lot of times i use the stone cutters and just turn them by hand. This just cleans up the existing seat that was already cut. Then different angled cutters are used to change the width of the seat and to raise or lower the seat to valve contact area. There are some good books (and i'm sure videos) that show how to cut valve seats and the techinic used. I suggest not using the tools you pictured if the pilots don't fit tight in the guides.

https://www.youtube.com/watch?v=mWi1I2EEz6M

This guy explains things really good.
 
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Thanks Vpd66. I have a little experience cutting/grinding valve seats but it was with professional cutters and grinders on a professional set-up. I didn't own them and don't have access to a good set-up. I thought I could turn these gently by hand to get some decent results but when I got the kit I was pretty nervous about trying it. Maybe I can be easy with them and aim to have the valve lapping to secure the 45 instead of cutting it in close. Cut and blue the valve just right so that I can lap the crap out of it to get the valve seated at the proper height and that will ensure that atleast the 45 is nice and conical.

I can't validate finding a machine shop and paying almost as much for a valve job as what it cost to buy the engine, or even more. Since I have knicked the valve seat already and probably will again they kinda need to be cut anyway. A lap job to take out the knick will screw up the valve depth. And then most importantly the 3 angle valve job should not only provide more flow at the seat but should also prevent unwanted fuel sheer into the cylinder. The efficiency that will be gained from a multi angle valve seat at low valve lift is going to be key to getting the most out of my engine.

I can't think of another way of getting a multi angle seat without spending a silly amount of money. I think I have to try this and try to make it work. I don't know anyone that just has professional valve cutting or grinding set-ups anymore that I can borrow or who would cut them in. I want to wet-flow the heads and make adjustments if needed. So I guess I'm stuck with trying these out. I know it's not ideal but I can't find a quality used set that I need and am unwilling to pay $250 for a set that I doubt I will get enough use out of to qualify the cost and don't want to spend $80+ dollars for a shop to cut them in and then possibly have to cut them one or 2 more times to get the proper flow and sheer.

I guess I just need tips for using these and getting decent results.
 

mckutzy

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Cutting valves is a precision job... so itll be payed a precision rate..... Ya its a bit... but thats where its at... and the job gets done right, as you spec it....
 

vpd66

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I don't know your location but any automotive machine shop could cut the seats for you and I doubt they would charge that much for 2 seats. Also look around your area for any go kart racing engine builders. These guys will have the correct tools and know how to do a precision job. Once again I doubt they would charge you much to cut 2 seats.

Has far has buying the tools go, I say its a buy once cry once situation. Or you can look at it has an investment. Buy it now and pay the price. Then when you feel you no long have a use for it sell it and recoup your money. These type of speciality tools hold there value if taken care of and there is always someone in the same situation you were in and will buy it. I've bought a lot of these types of tools used and saved a lot of money. The deals are out there but you really have to hunt them down tom find them. The best deal to date for me has been a Van Norman boring bar I bought for $125.00. It was listed on Craigslist for $500 and I watched it for 3 weeks before I decided to go look at it. The guy was desperate to sell it and told me to make an offer. I said $125 and he said "its yours".
 
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Cutting valves is a precision job... so itll be payed a precision rate..... Ya its a bit... but thats where its at... and the job gets done right, as you spec it....

I realize that, I just can't justify the cost and don't want to spend that much. Especially if I want to get them tweeked after running the head on a wet flow once or even a few times. That's why I was hoping to be able to do them myself, so I can tweek them as I wanted.

I don't know your location but any automotive machine shop could cut the seats for you and I doubt they would charge that much for 2 seats. Also look around your area for any go kart racing engine builders. These guys will have the correct tools and know how to do a precision job. Once again I doubt they would charge you much to cut 2 seats.

Has far has buying the tools go, I say its a buy once cry once situation. Or you can look at it has an investment. Buy it now and pay the price. Then when you feel you no long have a use for it sell it and recoup your money. These type of speciality tools hold there value if taken care of and there is always someone in the same situation you were in and will buy it. I've bought a lot of these types of tools used and saved a lot of money. The deals are out there but you really have to hunt them down tom find them. The best deal to date for me has been a Van Norman boring bar I bought for $125.00. It was listed on Craigslist for $500 and I watched it for 3 weeks before I decided to go look at it. The guy was desperate to sell it and told me to make an offer. I said $125 and he said "its yours".

I agree. I have seen one old (1950-1960's) valve grinding kit kinda near me for $250 but it doesn't look to have any small stones, especially since it's so old I doubt it has a 27/25mm set of stones. I will check with the local engine specialist shop to see what he would charge and if he has the right tooling to do it. The problem is that I know that I am picky and will want to try to tweek them little by little. I will try to get ahold of a gokart shop near me too. I have searched before but didn't have any luck.
 

vpd66

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The stones are the cheap part. I think the last time I bought some (about 3 years ago) they were $8.00 to $15.00 range. Make sure all the pieces are there. It should come with a stone dresser and you can use that to make larger diameter stones smaller diameter. I had to do the recently for an Honda engine I was working on. The smallest diameter the stones come in is 1 1/8". Pilots run about $40.00-$65.00 I had to buy a 5.5 mm pilot. I'm picky about cutting my seats to that is why I bought my own tooling to do it. I bought my Sioux valve grinder with seat cutter form a guy that restored tractors and he was retiring and selling off his tools. He bought it brand new in 1983 and took good care of it. It was very clean and everything was there and working. I paid $900 for it. I've done many valves and seats with it and I only had to buy 1 pilot (5.5 mm) and 2 stones. Someday when I decide I have no use for it I don't think I'll have a problem getting my money back out of it.
 

SuperBlazer

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If you're looking to clean up an existing seat that doesn't seal then I would use a lapping tool with lapping paste. I used this method on my VW bugs 1600cc heads that didn't seal and worked for me. If you're going with a bigger valve then cutting is the way to go. Cheap sucksion cup lapping tool that works.
 
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The stones are the cheap part. I think the last time I bought some (about 3 years ago) they were $8.00 to $15.00 range. Make sure all the pieces are there. It should come with a stone dresser and you can use that to make larger diameter stones smaller diameter. I had to do the recently for an Honda engine I was working on. The smallest diameter the stones come in is 1 1/8". Pilots run about $40.00-$65.00 I had to buy a 5.5 mm pilot. I'm picky about cutting my seats to that is why I bought my own tooling to do it. I bought my Sioux valve grinder with seat cutter form a guy that restored tractors and he was retiring and selling off his tools. He bought it brand new in 1983 and took good care of it. It was very clean and everything was there and working. I paid $900 for it. I've done many valves and seats with it and I only had to buy 1 pilot (5.5 mm) and 2 stones. Someday when I decide I have no use for it I don't think I'll have a problem getting my money back out of it.


Yeah, that's great. I'm glad you have been able to put them to use. I was just hoping to be able to grab a mediocre set that would give good results if you took your time. They said they were a knock-off of nuway so I thought they were a tapered dead pilot system but they are a live pilot system and the pilot is a little loose. I know some guys will use a heavy high speed oil to take up the slack but I just don't care for the live pilot systems, especially if they are a cheap kit. You can get chatter, out of round seats, screw up your guides and with the cutters you can take a ton of material away in a hurry and end up with a sunken valve. Maybe I will give it a try after a few shots and just see what happens lol

If you're looking to clean up an existing seat that doesn't seal then I would use a lapping tool with lapping paste. I used this method on my VW bugs 1600cc heads that didn't seal and worked for me. If you're going with a bigger valve then cutting is the way to go. Cheap sucksion cup lapping tool that works.


Thanks but I am trying to improve the Venturi Effect at the valve seat to improve flow at low and mid valve lift as well as reduce unwanted fuel seperation due to sheer at the valve/valve seat area. Before I decided to alter the ports and things on the engine I just wanted to take the governor out, tidy up any manufacturing or assembly flaws, etc and I lapped the valves in then. I blued the valves to see how the seats were set and widths and theyy were both in need of lapping. The exhaust only had about .0010 seat contact width and tge intake needed to be set back about .020 to center it so I took the time to lap them in then. Now I want to do atleast a 3 angle valve job to improve the valce/seat characteristics. It's probably the second most important aspect of air/fuel delivery and where you can make the most improvements.
 

Brianator

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I'm a little confused as how you are going to accomplish this multi-angled valve job for a couple reasons :

- no matter how you are going to remove the "knick" in the seat you'll have to remove the same amount of material so how is cutting or lapping different in that respect?

- "lapping the crap out of it" to get the angles matched is something I don't see working. When I lapped my cars cylinder head before taking it to the automotive machine shop for cleaning and resurfacing i asked the guy how my lap job was, he said it could use a little bit more. When i said i had been afraid to go too far with it he just laughed and said "you could be at it all day and not take too much off but good luck trying!" Lol.

By the time you add up tooling, possible replacement of valve seats, valves ect. and add a little something in for you time I'd imagine you'll surpass the costs of paying for a professional job.

I appreciate what you're trying to accomplish here as I'm the kind of guy that does (almost) everything myself so please don't take what I've said as disrespect, when it comes to that kind of precision that requires expensive equipment I prefer to let the pros that have it do their thing!
 

vpd66

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If you're looking to clean up an existing seat that doesn't seal then I would use a lapping tool with lapping paste. I used this method on my VW bugs 1600cc heads that didn't seal and worked for me. If you're going with a bigger valve then cutting is the way to go. Cheap sucksion cup lapping tool that works.

He is working with the flow of the ports and valves and wants to cut multi angle valve seats. Lapping valve is a good way to get valves to seal. I lap all mine after I cut the seats.
 

itsid

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Sorry, just thinking out loud...

TIF, didn't you have a lathe?

couldn't you grind and cut the valve poppet into a matching thread and
use the original stem as a pilot?
that should be fairly limited in play, no?
a short shaft welded on and a flexible shaft coupling to compensate for offsets in the powertool... might work, no?

'sid

PS again nevermind me, might be something I'm missing in cutting valve seats..
never done such thing myself (only ever had it done once and didn't even looked over his shoulder back then)
 
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I'm a little confused as how you are going to accomplish this multi-angled valve job for a couple reasons :

- no matter how you are going to remove the "knick" in the seat you'll have to remove the same amount of material so how is cutting or lapping different in that respect?

- "lapping the crap out of it" to get the angles matched is something I don't see working. When I lapped my cars cylinder head before taking it to the automotive machine shop for cleaning and resurfacing i asked the guy how my lap job was, he said it could use a little bit more. When i said i had been afraid to go too far with it he just laughed and said "you could be at it all day and not take too much off but good luck trying!" Lol.


By the time you add up tooling, possible replacement of valve seats, valves ect. and add a little something in for you time I'd imagine you'll surpass the costs of paying for a professional job.


I appreciate what you're trying to accomplish here as I'm the kind of guy that does (almost) everything myself so please don't take what I've said as disrespect, when it comes to that kind of precision that requires expensive equipment I prefer to let the pros that have it do their thing!




The lapping processThe valve will only seat on one of the angles (usually the 45 degree) and then you have angles above and below the 45. When you lap a valve you are just lightly grinding down the 45 degree seat area. You can't lap different angles into the seat. However, if you don't get the above and below angles absolutely perfect it will still seat properly as long as you have a conical and well mated 45. So I could cut the 60, then 45 and then 30 and if the 45 wasn't perfect then I could "lap the crap out of it" with the valve to ensure it was conical and well mated on the mating surface of the valve/seat sealing surface. If I just lapped the knick out of the 45 angle then the seat would be too deep in the pocket. You have to keep the seat in the middle portion of the 45. So I would cut the angles, blue it to check the seal area and then leave it a little high so that I could "lap the crap out of it" to make up any out-of-roundness to be sure the valve seats in conical and at the right seat width and depth.



I'm not sure what isn't clear about the difference between lapping and cutting multi angles on a valve seat. You can't lap in extra seat angles, you have to cut or grind them into the valve seat. The stock valve seats only have a 45 degree angle. It goes from 90 degrees up, 45 degree for the seat and then 180 degrees. I want to cut in a 60 degree below the 45 and a 30 degree above the 45.


The reason I want to do it myself is because every engine wants a different valve job. You run the head on a dry flowbench to check dry numbers and then wet flow to check fuel seperation, velocities, etc. You can keep adjusting minor alterations and make huge improvements in flow numbers as well as fuel suspension characteristics. I wonder how much it would be to drive 45 minutes atleast several times and have someone try to cut them exactly how you are thinking in your head. It just makes better sense to do it yourself.


I'm not spending $900, or even $250, on a kit to cut the valve seats on a silly $99 stock yardkart engine. Not sure what you don't get about that either. Just like I won't spend an equal amount of money driving to wherever just to bother an engine shop to try to get the valve seats to what I want. However, I would rather do it myself and would pay extra for it because I will still have the tools for future projects, I would be able to dial them in to my liking, gain experience and have the satisfaction of knowing that I did it myself. A $99 yard kart engine is a perfect platform for trying to accomplish things yourself.

Sorry, just thinking out loud...

TIF, didn't you have a lathe?

couldn't you grind and cut the valve poppet into a matching thread and
use the original stem as a pilot?
that should be fairly limited in play, no?
a short shaft welded on and a flexible shaft coupling to compensate for offsets in the powertool... might work, no?

'sid

PS again nevermind me, might be something I'm missing in cutting valve seats..
never done such thing myself (only ever had it done once and didn't even looked over his shoulder back then)


No, I don't have a lathe. I could make my own pilot and whole set-up for the most part if I did. The stock valves are more tight than the pilot I got with the kit though. Good thinking and thanks for your comment but I don't have a lathe.
 

Brianator

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I'm very aware of what lapping involves and the goal, on my first attempt I was taught I did it too little.

You need to back cut the valve after defining your 45° angle to accomplish a multi-angle valve job, just wondering how you're planning to do that.
 
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It's not absolutely critical to the sealing of the valve so I can cut it, grind it, sand it, polish it with a rotary tool in a jig,

The multi-angles I'm cutting in are mainly in the seat. Then back-cut the valves 30 degrees or there-abouts.
 

SuperBlazer

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That tool set should come close to what you're looking to do or use the the stones. Practice on a spare or junk piece for your first time cutting (with new tool)and get the feel of how much material your tool removes at different speeds and pressure. Take pictures of your process and results and please share!
 
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That tool set should come close to what you're looking to do or use the the stones. Practice on a spare or junk piece for your first time cutting (with new tool)and get the feel of how much material your tool removes at different speeds and pressure. Take pictures of your process and results and please share!


Thanks for that. I don't have anything that will work for testing on. I guess I will just have to get my courage up try it with extra caution. Will do :thumbsup:
 
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