Case lapping tool

[Mike in Mass]

Good evening all! I'll be replacing the roller bearings and the case outer races in my '54 Pan soon, and want to size the case races myself. Has anyone used the Eastern MC Parts lapping tool, any good/bad things to say for it?
Sure appreciate any info you can spare the time to provide.
Mike in Mass

[Saintly]

It's the one to get!

I've had mine for 5 years. I've done 3 evos, two shovels, a pan, an ironhead, and three ironhead gearboxes(main case race) with it.

I'm happy.

[Cotten]

Just my humble opinion folks,
but lapps are novelty items, like ridge reamers and flex-hones.

A common Sunnen hone will do the job faster, more accurately, and leave a far better finish.
Why spend heavy for a cranky tool when any competent automotive machine shop can do it in minutes, for a fraction of the price of the tooling?

You guys don't really think they lapped them at the factory, do you?

And Mike!
Are you arbitrarily replacing the races, or are you certain they worn beyond a re-fit?

...Cotten

[steinauge]

By "flex hone" I assume you mean the 3 legged spring loaded cylinder killers not the common ball hone? I have seen the picture of the Sunnen with the case on it before and wondered what you were using on the other side to maintain alignment?

[Cotten]

Steinauge!

By the term "flex-hone", I meant a berry-bush ball hone, although J.C.Whitney glaze-breakers are just as worthless.

I take that back.
Ball-hones are usefull for prepping a fossil cylinder for inspection, to ease abuse upon a boregauge.
And of course, any cylinder doomed for recycling at swap meet is greatly enhanced!

But otherwise, to quote Hastings Rings over the phone many years ago: They are great for stirring paint.
Instead of a positive cut as a fixed stone produces, they tear a mill profile.
I used one religiously, of course, for "re-ring" jobs when I worked auto shops. The ring wear at the top of a cylinder is made quite apparent by a positive stone, as it does not touch the bottom of the valleys. But a berry-bush gives the appearance of a flat surface, and a cross-hatch that fools the layman.

On to the Sunnen,
If both races are to be fitted to the same roller size, then the stones and shoes of a double-stone mandrel centers itself off the races.
But when the races must be fitted separately, as most of the time,
then the trick to line honing is to use a 'wiper' in place of one of the two stones on a double-stone mandrel.
Here you can see where I bonded nylon to a spent stone holder (on the left), and ground it to match a dressed stone.

WIPERSTN.jpg

I made a selection of thicknesses quite easily, and can swap them to accomodate the stone's wear.
And swapping their positions upon the mandrel allows for proper over-stroking, from both directions, and even wear.

(The narrowed stone above allows for stock removal in a very specific tight spot, without bell-mouthing or relieving the rest of a bearing surface. This is particularly useful for Chiefs. A lapp tends to "screw" upon high spots.)

On to tranny mains, I made a press-in insert to match the roller bearing housing, with a spent main race within it.
Thus I could pilot off the opposite side of the case.

It cuts an afternoon's labor into a forty minute chore, including clean up.

....Cotten

[Mike in Mass]

Saintly,
Thanks alot for the first-hand info!
Cotten,
It's obvious your experience level is way beyond mine. My goal is to keep this bike in the family ( my dad bought it in '63, got too frail to drive it about 8 years ago, and I finally wrestled it away from him 2 years ago) and amass spare parts and tools so me and my two sons and hopefully one day grandsons to run it as long as they make gasoline the poor thing can run on. Dad wasn't much on maintenance except for pretty regular oil changes. When I got the bike it would start easily but ran rough (rich) and once it stopped wouldn't start again for at least 1/2 an hour. I did some research and suspected int manifold leak plus compression was only 70 - 75#. Pulled top end and found crack in rear head from spk plug hole to exh valve seat. Cylinders were .070 over and somewhat scored plus some broken fins. Had hoped to get away w/o cracking lower end but once top end was off I measured crank side-to-side play and was close to .040. Plus when I saw the layer of crud in the gear case I couldn't stand the thought of putting a nice fresh top end on a lower end with so much crud in it. Split the cases and found the sprocket shaft was burnt on the roller surface near the flywheel with some what looks to me to be pretty bad pitting there too. The race was pretty blue inside as well. I have a nice bore gage coming in a few days and I'm hoping the races can be reused by lapping them to the next oversize rollers. The pinion side may not need any attention, the shaft looks good and the rollers and race look pretty good by eye, we'll get the measuring instruments out later this week.
As for having a shop do the work I like doing as much of my own work as I can, tho not a born motor-head like some of you, the voodoo of internal combustion has always fascinated me ( and often eluded me)!
I've found a set of STD heads with the correct intake and exhaust fittings for a real good price to use until I can get my originals reworked. I've got some aftermarket cyl's and Wiseco pistons to use 'til I can get the originals resleeved and repaired. Hoping to get this bike ('54 Pan with 86K miles on her) out this summer but may be somewhat optimistic as the tranny sounds awful loud in second and third. It'll be coming apart, too.
Do you still make the PEEK manifold seals?
Hope you all don't mind if I throw a question out here once in awhile and I'll try to find a minute to throw a pic or two of Betsy out here when I can.
Once again, thanks for all who took time to share info, and watch out for them ritalin-takin', cell-phone texting, CD changing, baggy pants sideways-hat-wearin' knuckleheads (not HD kind) careening around out there with their learner's permit in their hand this season!
Mike in Mass

[steinauge]

Cotten,thank you for the info on using the Sunnen hone to size case races.I find it odd that H.D is so insistent on using ball hones for everything from rocker arm bushings and valve guides (after reaming) to honing cylinders (after paralell honing). Any ideas?

[Cotten]

Cotten,thank you for the info on using the Sunnen hone to size case races.I find it odd that H.D is so insistent on using ball hones for everything from rocker arm bushings and valve guides (after reaming) to honing cylinders (after paralell honing). Any ideas?

Steinauge!

The answer is an easy one.
H-D has been 'downsizing' the need to pay skilled service technicians for a generation.
And that included elimination of machinery from the boutique floorplan.

Any idiot can whack off with a cheap ball hone, and it fits in a drawer.
The last time I checked out new Sunnen pedestal machines, they started around $6000, with an enormous "footprint".

Throughout the late 1980's and early 1990's, the MOCO encouraged dealerships to ship as many obsolete models overseas as possible. "Parts-changers" couldn't work on them like an evo, where precision fits were engineered out of them.
At one point the MOCO proudly announced that over half of all Shovels still in service were overseas.
That had to make stockholders smile.

Lapps, ball-hones, and even adjustable reamers all have their time and place.
They are for field repair tools, intended to get a piece of machinery back in service quickly and cheaply, by un-trained hands.
What is ironic is that the simplest tool of all, the machinist's scraper, can often fit a bushing better than even a Sunnen, but finding a modern machinist who knows how to scrape is like finding a Knuckle in a barn.

LEVIT3.jpg

....Cotten
PS: Cheap India scrapers levitate best.

[steinauge]

Cotten thank you for the info. Actually I am quite familiar with machinists scrapers,used one of mine sunday to touch up a #1 cam bushing on a 45.I never thought of using one to size the bushing from scratch since that is an align reaming operation.??I first heard the ball hone business from HD in 1975.I assumed the ball hone the rocker arm bushing business was to try and allow for a lot of dull reamers.However Their explanation for ball honing the cylinder after paralell honing made perfect sense.

[Cotten]

Steinauge!

Scrapers should have had a revival when pre-sized bushings became all you could get from the usual distributors.
Often it is only the pucker from dowelling that must be scraped away (whereas a reamer or hone tends to 'walk' to the opposite side. My piloted reamers are all under journal-size, and occasionally knick only one side of a pre-sized bore: Might as well just scrape it.)

Where triangular scrapers really come in to their own is with flatties' gear-train bind problems, such as after a case weld repair.
Inking and scraping to bias so many bushings can be tedious, but tossing any other tools at them results in a sloppy cam chest.
Flat scrapers are critical for everything else......!

....Cotten

[indianut]

So what do you do on the Pinion side of a 55 up Pan?

[Cotten]

Mike in Mass!

Sorry for the late reply, but yes, I still recondition manifolds with PEEK, as do many folks around the world.
For those of you with pristine or new manifolds, cast seals are available from http://www.enfieldracing.com/8.html at a considerable savings.

And Indianut!
If you mean the cam cover pinion shaft bushing, I approached it the same way:
After line-reaming undersize, piloted from the right case main race, honing was usually my first option, if alignment proved precise.
But in many cases, inking for trial fits shows high spots of the bushing bore that requires relief with the scraper, often to one side. Gentle cross-hatching can remove a couple of tenths of a thou in select spots quickly. This must be repeated many times, however.
A final finish with an Adalox tube brush takes seconds, and works better than ink for the last few fits.
It takes a great deal of time, patience, and observation through many trials of the assembly, but the result is worth it.

Everybody should realize, of course, that the absolute best way to set up any gearcase is to bore the installed bushings to blueprint on a mill.

....Cotten

[indianut]

What I am wondering is how you pilot off of the Timken race to hone the Pinion race in the right case with the Sunnen? Thanks!

[NightShift]

Dear Indianut,
You might really not want to know!

HONGUIDE.jpg

R'spectfully,

[indianut]

Thanks for the pic! That just proves what I tell people all the time. "We aren't building the Space Shuttle" I will make an adapter similar to what you have shown me. Again, thanks!