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07-14-2018, 06:51 PM | #1 |
Scooby Newbie
Member#: 196882
Join Date: Dec 2008
Chapter/Region:
MWSOC
Location: Holset baller on a budget.
Vehicle:08 WRX |
Lifter bucket grinder?
I need to remove some material from one piece lifter buckets to set lash. My lash changed about .001 after lapping and Im on the tight side now.
I want to use a mill and cutter, end mill, grinding bit, whatever, to take off some material. I can see some guys use dremil bits on a drill press but Im hoping to find something a bit more reliable in tems of straight/square. Im thinking a thicker shank (Dremil is 1/8) and maybe a fine stone? Ideas for a bit to get this done and leave a decent finish?
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07-14-2018, 07:22 PM | #2 |
NASIOC Supporter
Member#: 30669
Join Date: Dec 2002
Chapter/Region:
Tri-State
Location: USA, North NJ, 07456
Vehicle:1998 Legacy 2.5GT Silver Sleeper BK, 5MT |
Surface grinder with a magnetic base/table, very small cuts. Maybe run a green wheel (normally used for carbide).
Everything else is.....well.....ghetto.... Granted, other methods can work, you REALLY want a smooth flat finish. Otherwise, you can wipe out a cam lobe, then, you start all over.......for many valves...... I am not a machinist, I'm a decent "metal hacker". I have a few years working on my own and in shops. I know when to "MacGuyver" and when to do it right. |
07-14-2018, 09:51 PM | #3 | |
Scooby Specialist
Member#: 141952
Join Date: Feb 2007
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MWSOC
Location: milwaukee'ish
Vehicle:2023 M340i |
Quote:
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07-15-2018, 12:24 AM | #4 |
Scooby Newbie
Member#: 196882
Join Date: Dec 2008
Chapter/Region:
MWSOC
Location: Holset baller on a budget.
Vehicle:08 WRX |
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07-15-2018, 01:29 AM | #5 | |
Scooby Specialist
Member#: 419354
Join Date: Apr 2015
Chapter/Region:
MAIC
Location: Newark, Delaware
Vehicle:2007 STI Crystal gray metallic |
Quote:
You can always just order the correct size... they're only $15-$20. |
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07-15-2018, 08:34 AM | #6 |
Scooby Newbie
Member#: 196882
Join Date: Dec 2008
Chapter/Region:
MWSOC
Location: Holset baller on a budget.
Vehicle:08 WRX |
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07-15-2018, 04:50 PM | #7 |
Scooby Specialist
Member#: 283429
Join Date: May 2011
Chapter/Region:
South East
Location: Down yonder.
Vehicle:2016 Fuji Sunfire 03 Silver |
I have seen folks grind the valve stem tip, but never the bucket - that is some hard material there...
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07-15-2018, 07:56 PM | #8 | |||
NASIOC Supporter
Member#: 30669
Join Date: Dec 2002
Chapter/Region:
Tri-State
Location: USA, North NJ, 07456
Vehicle:1998 Legacy 2.5GT Silver Sleeper BK, 5MT |
Quote:
Quote:
Suitable stone (green for carbide is best), keeping surface flat, etc. limited room to work. If you hack at it, likely less than flat surface which will change gaps with little wear. Also, grinding heats the material, thus harder to measure, reset, then grind more. Quote:
Checking gaps on a bench is one thing, checking when the head is torqued to a block may be another. Doing something on a weekend when no new parts are around is one thing, doing something that lasts for 50K+ miles is another. Not saying you can't hand grind within a bucket to get a gap, just really hard to do right. |
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08-08-2018, 09:46 PM | #9 |
Scooby Newbie
Member#: 489895
Join Date: Aug 2018
Chapter/Region:
Tri-State
Location: North New Jersey
Vehicle:2005 STi PSM |
I thought about this myself and I think the best way is order a new bucket.
The second best way is to keep lapping it. And the quickest way to take off a bunch of material is on a lathe with a really rigid setup and a carbide tip. Indicate it straight withing a few tenths and take a pass a few tenths shy of where you need to be. I would only use this method if you're taking material off the inside of the bucket. That being said, i don't know if there's any geometry inside of the bucket on the boss tip. you could run an indicator on the boss to find out if its concave, convex or flat. |
08-10-2018, 05:59 PM | #10 | |
Scooby Guru
Member#: 428511
Join Date: Aug 2015
Location: philadelphia
Vehicle:2016 STI |
Quote:
I'm guessing you've never done anything like that on a lathe. |
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04-30-2020, 03:52 PM | #11 |
Scooby Newbie
Member#: 443465
Join Date: Mar 2016
Location: Southern Indiana
Vehicle:2004 WRX Silver |
FWIW...I did exactly what the OP was looking to do last night using a dremel and a flat-faced mounted grinding point and easily held my tolerances to less than 0.001".
I have a mounting adapter that allows me to remove the threaded nose piece on the head of my dremel and screw this mounting adapter on in it's place. The mounting adapter allows me to mount the dremel to the tool post on my metal lathe (an old South Bend Heavy 10). So, I wrapped my buckets in tape to protect the OD, then used a 3 jaw chuck with a stop piece behind to hold the bucket in the lathe's chuck and (more importantly) keep any pressure against the nub while grinding from being able to push the bucket away from the grinder and into the chuck. After carefully checking my valve clearance, I removed the buckets one at a time, chucked them up, brought the flat face of the mounted grinding stone up to the "nub face", turned on the lathe to spin the bucket at about 200 RPM and turned on the dremel to turn the grinder at about 10,000 RPM...then used the compound wheel to advance the grinder into the nub. The centers of the nub (as spun by the lathe) and grinding point were offset so I wouldn't have a spot where the surface speed of the grinding point was zero against the nub. By careful work I was able to grind 5 buckets to exactly the desired feeler gauge once reinstalled in the head.(less than +.000/-.001 from nominal). The least I removed from any bucket was .002. The most was .009. I spent about an hour and a half in total on the project, including about 20 minutes setting up the lathe. It took 3 to 5 cuts, checks, and recuts per bucket to bring them to nominal. A good depth mic was important here to check and recheck to see how much material has been removed. The nub surfaces are smoother and shinier on the ones I worked then the ones that checked in spec before I started. I took the time to do a very thorough cleaning of each bucket before reinstalling it in the cylinder head...that grinding dust would NOT be good for an engine. I figured it was worth a shot to resize my old buckets. Worst case I'd ruin one (cut too much or mar the OD) and be buying a replacement...but so far I'm 5 for 5 on mine. One head down, one to go. Phil Last edited by HoosierBuddy; 04-30-2020 at 04:15 PM. |
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