Trimming steel reatainers

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cgarb
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Trimming steel reatainers

Post by cgarb » Mon Nov 13, 2017 9:49 pm

I have a set of steel retainers that are close to hitting my rocker arms. Has anyone ever faced the top side off a little to gain clearance. Remove maybe .030" of material. That much wont even totally remove the chamfer on the OD and the long angle on the face down to the top of the 10 deg bore. Maybe could cut a few grams of weight and gain clearance. I saw an extreme example in an older engine building book somewhere that they cut scallops in the od and drilled hole in the top. Nothing like that just a small face cut.

statsystems
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Re: Trimming steel reatainers

Post by statsystems » Mon Nov 13, 2017 10:08 pm

cgarb wrote:
Mon Nov 13, 2017 9:49 pm
I have a set of steel retainers that are close to hitting my rocker arms. Has anyone ever faced the top side off a little to gain clearance. Remove maybe .030" of material. That much wont even totally remove the chamfer on the OD and the long angle on the face down to the top of the 10 deg bore. Maybe could cut a few grams of weight and gain clearance. I saw an extreme example in an older engine building book somewhere that they cut scallops in the od and drilled hole in the top. Nothing like that just a small face cut.

Yup. Many of them. Made up some soft jaws, grabbed them in the lathe and machined them off.

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Re: Trimming steel reatainers

Post by cgarb » Mon Nov 13, 2017 10:15 pm

I got a collet chuck and some 5C step collets. Will do the trick. Thinking about cutting a 10deg taper on the .710 diameter. It wont be any thinner wall thickness than what it is at the shoulder already. Cant hurt anything I wouldn't think, plus still locate the inner spring just fine still.

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Re: Trimming steel reatainers

Post by ProPower engines » Mon Nov 13, 2017 10:29 pm

Depending on the degree of lock you can also just machine a tapered mandrel to grab them in the center with a lock nut to retain them.
Goodson and others sell them if you need a reference to look at :D

in the old days there was not as many options for rockers and retainers that there is now and machining retainers was a very common thing to do.

Happy whittling :lol:
Real Race Cars Don't Have Doors

cgarb
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Re: Trimming steel reatainers

Post by cgarb » Mon Nov 13, 2017 10:54 pm

Have the retainers and lathe...labor is cheap...lol. What else would I rather be doing?

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amcenthusiast
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Re: Trimming steel reatainers

Post by amcenthusiast » Mon Nov 13, 2017 11:45 pm

First off, for anyone who's not taken a metal shop course, I'd highly recommend it if you like any type of metal working; it's a lifetime thing -like learning to ride a bicycle -you never forget (I'm permanently thankful to my teacher -I loved that class)
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Because I needed to make so many custom parts for my less popular engine, I began to search for a small lathe and found some for sale on Craigslist... you can't get lucky if you don't try.

Edit: One might also find local machinists on Craigslist to do such a job as well.

Depending on how much you enjoy your auto hobby, a benchtop lathe can be an excellent tool to add to your existing tool set.

I wound up making my own (with much planning and studying of course!) for only about $250 it quickly paid for itself. (I used a modified rear axle pinion gear assembly for the spindle! -super heavy duty with low cost easy to replace bearings!)

Since then I tend to hunt for 'sweet little jobs' I can do on my lathe. (perfect for cutting custom valve spring retainers)

Anyone can see my DIY lathe on my Google+ profile page:

https://plus.google.com/106358430530058382730

(Richard is my Dad's name, I'm David)
XRV8 Race Parts > for AM's '56-'67 Rambler V8: http://amcramblermarlin.1colony.com/favorite_links.html

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Re: Trimming steel reatainers

Post by KnightEngines » Mon Nov 13, 2017 11:56 pm

For future reference, here's a trick I use to make machining retainers easy:

I have a spare set of old jaws for my 3 jaw chuck for the lathe.
I clamped a chunk of metal around the size of the average retainer in the jaws set back from the front so the front of the jaws was exposed, then I used a boring bar to put a .060" deep step in the jaws.

Now when I gotta machine retainers I don't have to clock them up or anything, just put those jaws in & the retainer locates solidly in the step, then I can zero my slide indicators when I do the 1st one & just smash the rest through cutting to the zero on the slide, measure every 4th retainer to be sure nothing has moved (it never does). Cut the time to machine 16x retainers down to like 25% of what it used to take.

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Re: Trimming steel reatainers

Post by cgarb » Fri Nov 17, 2017 6:09 am

IMG_20171117_060009588.jpg
Trimmed .030" off the top face for rocker clearance added the .060" deep trepan groove, it was a .120" wide radius tool, no sharp corners. Cut the 10 deg taper on the .700 step for the inner spring ID. Went from 33 grams to 26 grams. 7 grams weight savings. With the step collet set up I can do one complete in about 10mins. A little Permablue from my gunsmithing bench and they look like new. Worth it? Who knows, but nobody will have retainers just like mine.
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statsystems
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Re: Trimming steel reatainers

Post by statsystems » Fri Nov 17, 2017 10:42 am

cgarb wrote:
Fri Nov 17, 2017 6:09 am
IMG_20171117_060009588.jpg

Trimmed .030" off the top face for rocker clearance added the .060" deep trepan groove, it was a .120" wide radius tool, no sharp corners. Cut the 10 deg taper on the .700 step for the inner spring ID. Went from 33 grams to 26 grams. 7 grams weight savings. With the step collet set up I can do one complete in about 10mins. A little Permablue from my gunsmithing bench and they look like new. Worth it? Who knows, but nobody will have retainers just like mine.
Very nice.

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Re: Trimming steel reatainers

Post by Geoff2 » Sat Nov 18, 2017 2:32 am

In my opinion, the 0.060" groove [ trench ] has seriously weakened the retainer.

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