Line boring ( Ariel Square Four was Parkerizing) | GTAMotorcycle.com

Line boring ( Ariel Square Four was Parkerizing)

nornet

Active member
Some of you may remember my posts regarding the suitability of Parkerizing a camshaft for this motorcycle. This work has been done in conjunction with grinding the cam

It has taken me about a year and a half to source the remaining parts.

Much of the machining is under way. (new valves, guides, bearings etc)

One service I have been unable to locate is someone who is experienced in line boring.
I have new plain bearings, babbit lined, that need to be machined to size. This must be done when they are in both crank cases.

Does anyone know of a shop around the GTA that can do this? Most shops use conventional boring equipment.
 
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I would start by talking with Gord Bush Performance or Bondi Engines. If they don't do it, they should know who does.
 
Gord can't do the work, basic boring yes but not line boring. (He is doing my valve guides now).
Haven't talked to Bondi (sent an email). From their website I don't get a comfortable feeling regarding vintage bikes.
 
Gord can't do the work, basic boring yes but not line boring. (He is doing my valve guides now).
Haven't talked to Bondi (sent an email). From their website I don't get a comfortable feeling regarding vintage bikes.

I get it, that's a cool bike. Make sure you post lots of pics to give us something to drool over.
 
Ariel.jpg



I bought this bike in about 1965. Second owner I believe. It came with crash bars front and rear, leather saddle bags and a sidecar. The previous owners kids pretty much destroyed the sidecar to the extent I didn't even pick it up.
It probably came from Percy McBrides on Queen St.

This pic is from about the 70s.
 
didnt they come up with a fitment of needle roller bearings ? or is that just for big ends? I read that someplace, maybe the Dragonfly Spares page
 
didnt they come up with a fitment of needle roller bearings ? or is that just for big ends? I read that someplace, maybe the Dragonfly Spares page
The rods have standard shell type bearings. The bearings on one side of the cranks are ball bearings. The other side is a bronze Babbitt lined bearing. They (Dragonfly) only sells one size of the bronze bearing. It is about 100 thou undersize so it can accommodate regrinds. Save on stocking parts I guess.

I think possibly some of the singles and twins had roller bearings.

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Some of you may remember my posts regarding the suitability of Parkerizing a camshaft for this motorcycle. This work has been done in conjunction with grinding the cam

It has taken me about a year and a half to source the remaining parts.

Much of the machining is under way. (new valves, guides, bearings etc)

One service I have been unable to locate is someone who is experienced in line boring.
I have new plain bearings, babbit lined, that need to be machined to size. This must be done when they are in both crank cases.

Does anyone know of a shop around the GTA that can do this? Most shops use conventional boring equipment.

do you have to do more than one set of bearings at at the same time?
is this why the line boring request?

I know some people in that business, but with, and for large equipment
so you're looking for someone with a line bore jig to work inside the casings?

back in the day I recall those babbit bearings were sized with a reamer
but would be hard to do 2 of them at the same time, on the same plane
 
whats the total length of cut you need? Small engines dont need line boring machines because you can usually get away with standard boring bars which will reach from one side of the head to the other. For instance I can bore up to 9" deep down to a min of 1" diameter with our current modular system at work. Smaller than 1" I can get down about 6" or more if we buy the modular extensions for our boring system

That being said, most, if not all engine machine shops are using extremely primitive machinery at best. The technology in any modern machining facility today has boring systems that can reach fairly deep.
 
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At the last place I worked we had really long boring extensions. A friend and I both rebuilt our project car engines at that shop on weekends, we line bored the block to fit a new crank and caps with standard boring equipment on a CNC horizontal machining center.

IMG_1453.JPGIMG_1230.JPGIMG_1450.JPG
 
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That being said, most, if not all engine machine shops are using extremely primitive machinery at best. The technology in any modern machining facility today has boring systems that can reach fairly deep.

Line boring is not done at auto shops anymore. Went out with hand poured bearings.

I am old enough that I have hand poured bearings. Iirc it was for a Fordson tractor. I sized them with a knife.


Is a Bridgeport "extremely primitive machinery"?
How about a precision Toz lathe?

Modern is easier to setup and is geared to production but someone that knows what they're doing with your "extremely primitive machinery" can do almost anything a 5 axis rig can do... it just takes a LOT longer.
Modern is real good at making a million pieces, not at all economical doing one piece. Making a million pieces involve a cad designer, then solid works, then prototype, then workout the tooling, then troubleshoot the tooling (cuz the tooling programs have a bad habit of plowing the tool into the work piece at the most inappropriate times), then setup, then trial runs, then finally production. Takes a large staff, comprised of a bunch of highly paid engineers and technicians.
At a manual shop you hand the machinist a drawing and say " Make me one of these". (Here is the "modern" problem. You need a guy that has all the practical knowledge to do the job. There are very few of those guys left and from my experience those guys don't work in production shops)(Most of "those guys" I know work that in production shops work in aerospace and HATE it. The only reason they're doing it is for the money).
If you were Toyota and had to lap a million valves it is worth the million dollars to set up a machine to lap those valves. If you work at an engine shop and you have to lap 8 valves it will still cost a million dollars to set up that machine. See the problem?
Engine shops do not deal in production, almost every job is a one off. Modern CNC won't work.
 
At the last place I worked we had really long boring extensions. A friend and I both rebuilt our project car engines at that shop on weekends, we line bored the block to fit a new crank and caps with standard boring equipment on a CNC horizontal machining center.

View attachment 39255View attachment 39256View attachment 39257

I line bored some Honda CB450 cases to accept over sized roller bearing mains. I did it on a Bridgeport.
In and out in an afternoon.
It's nice having friends with a well equipped tool and die repair shop. Line boring, like most machining processes, is not a hard job if you have the right equipment.
 
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Line boring is not done at auto shops anymore. Went out with hand poured bearings.

I am old enough that I have hand poured bearings. Iirc it was for a Fordson tractor. I sized them with a knife.


Is a Bridgeport "extremely primitive machinery"?
How about a precision Toz lathe?

Modern is easier to setup and is geared to production but someone that knows what they're doing with your "extremely primitive machinery" can do almost anything a 5 axis rig can do... it just takes a LOT longer.
Modern is real good at making a million pieces, not at all economical doing one piece. Making a million pieces involve a cad designer, then solid works, then prototype, then workout the tooling, then troubleshoot the tooling (cuz the tooling programs have a bad habit of plowing the tool into the work piece at the most inappropriate times), then setup, then trial runs, then finally production. Takes a large staff, comprised of a bunch of highly paid engineers and technicians.
At a manual shop you hand the machinist a drawing and say " Make me one of these". (Here is the "modern" problem. You need a guy that has all the practical knowledge to do the job. There are very few of those guys left and from my experience those guys don't work in production shops)(Most of "those guys" I know work that in production shops work in aerospace and HATE it. The only reason they're doing it is for the money).
If you were Toyota and had to lap a million valves it is worth the million dollars to set up a machine to lap those valves. If you work at an engine shop and you have to lap 8 valves it will still cost a million dollars to set up that machine. See the problem?
Engine shops do not deal in production, almost every job is a one off. Modern CNC won't work.

IMO, yes, bridgports and toss lathes are primitive, I never said they cant bore a hole tho.

We have 5 Five axis machines, we are a job shop, and make one offs all day long. I dont need cad to bore a hole on a half million dollar DMG 5 axis, but you do need the tools.

What I was reffering to in terms of primitive was more along the lines of tooling. Every shop Ive worked in for the last 20 years had modular boring systems, they start at five grand for simple setup and you can spend twenty times that to expand your abilities in boring.

If youre gonna lecture me on machining you had better know what youre talking about ;)
 
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Exactly, in most cases a normal generic boring head will reach a small engine depth of cut, just what I was trying to say. You dont need a line boring machine for small engines.

in todays machining world, If you need to bore deeper, you can use modular systems rather than needing a special machine.


I line bored some Honda CB450 cases to accept over sized roller bearing mains. I did it on a Bridgeport.
In and out in an afternoon.
It's nice having friends with a well equipped tool and die repair shop. Line boring, like most machining processes, is not a hard job if you have the right equipment.
 
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I started on a Bridgeport.
 

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