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Block line boring for camshaft


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I'm contemplating getting my cam line bored for bushes, to take up some slack in the bearing journals, and improve the oil pressure.

I have contacted Ivor Searle who can do the job, been done by them before, my question is, is there a dimension know from the centre of the crank to the centre of the camshaft hole?  If the entry point of the cam hole is worn a bit how does the machinist set up the line, just interested to know how its achieved/done.  Could it done from the rear end which is obviously not had any wear, and hope they can get it parallel and come out at the right spot at the front?

Any machinists on here?

John

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Can't answer exactly the question you're asking as I'm not a machinist, but I've visited Ivor Searle's premises for a classic magazine, to photograph a Spitfire engine being machined, including line boring and fitting cam bearings. I was impressed by what I saw.

Such work is meat and drink at Ivor Searle. They have been machining classic engines for literally decades. I would simply tell them what I want, and trust them to do it correctly.

By the way, they will want your new camshaft before fitting the bearings. They always trial fit the cam before signing off the job.

Nigel

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I would first ask the shop, before telling them how to. If you understand the logic and agree with it, gave it done. I also would ask how the final machining diameter is calculated; they will need the shells and camshaft for that.

Waldi

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...and w/r/t oil pressure, a tight fit in the bearing bores won't ensure good pressure ( though a loose fit can surely give poor pressure ). The grooves on the cam journals dam up the flow, and generous ones will give low pressure where fine ones give high pressure. If possible, ensure yours match TRIUMPH's, whether straight or spiral type.

 

Tom

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I've just had my TR5 block line bored for camshaft bearings. That and all other machining should be compete this week for me to collect.

I supplied my new cam to the m/c shop and they supplied and fitted the shells. The work is being done at Stanwood Engineering in Bawtry, South Yorkshire. No connection, but I have been very pleased by the workmanlike manner in which they have kept me informed of progress as the work has gone on.

I don't pretend to be an expert. However, I wouldn't have thought the specific dimension from centre line of crank to centre line of cam would be that important, as long as the cam bearings are within the original bores and crank and cam are parallel to each other. If it was different to the original any deviation, which would be very small, should be taken up by the timing chain tensioner.

Dave McD

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I believe Jason, the engine builder at TRGB uses Ivor. My Engine was rebuilt by Jason and hence rebored etc by Ivor and it seems pretty nice. It also means that Ivor has a lot of TR engines coming through so I am sure he knows his business.

Cheers

tim

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42 minutes ago, Tim D. said:

I believe Jason, the engine builder at TRGB uses Ivor. My Engine was rebuilt by Jason and hence rebored etc by Ivor and it seems pretty nice. It also means that Ivor has a lot of TR engines coming through so I am sure he knows his business.

Cheers

tim

Jason is no longer at TRGB but they still use Ivor Searle for machining and balancing.

By the way, Ivor Searle is not a one man machine shop, it's the largest independent engine re-manufacturer in the UK. The have a large factory complex, with modern engines on one side of the road and separate, fully equipped factory unit the other side which specialises in classic engines. It's a very impressive operation and I've no hesitation in recommending them. I will be taking my Scimitar's cylinder heads to Ivor Searle for overhaul next month.

Nigel

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Did that by myself and as you drill all the bearings in one setup it is not that critical.

The drilling shaft is centered in the first and last hole and that the block and machine are brought into proper position.

As the first bearing always is worn to one side it is not that critical because in the middle is an unused area where the recess for the oil feed was. If that is gone I would inspect the second bearing and you may have to fiddle a little bit to take the outside/upper area of the bearing as a master because the bearing is worn towards the crankshaft. But I did not do that because my middle of the first bearing was untouched and could be used as a gauge.

162428840_camandbearing01.jpg.1ab45e46cc467b05af999b15e4c3f133.jpg

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

424714147_LagerNockenwelle.jpg.ae581d645190f66790e3a3c048df7da6.jpg

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3 hours ago, TriumphV8 said:

Did that by myself and as you drill all the bearings in one setup it is not that critical.

The drilling shaft is centered in the first and last hole and that the block and machine are brought into proper position.

As the first bearing always is worn to one side it is not that critical because in the middle is an unused area where the recess for the oil feed was. If that is gone I would inspect the second bearing and you may have to fiddle a little bit to take the outside/upper area of the bearing as a master because the bearing is worn towards the crankshaft. But I did not do that because my middle of the first bearing was untouched and could be used as a gauge.

162428840_camandbearing01.jpg.1ab45e46cc467b05af999b15e4c3f133.jpg

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

424714147_LagerNockenwelle.jpg.ae581d645190f66790e3a3c048df7da6.jpg

AAaaaahhh our old friend the hand driven Symmetrical align boring tool, is that yours Andreas or did you just get used to it at where you work ?

Mick Richards

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10 minutes ago, BlueTR3A-5EKT said:

Respect... a home made tool that looks great, I'd use it.

It's surprising but you give a man a tool made in factories by machines and costs and arm and a leg against an owner who understands what he's trying to do and has engineering background and the results will be comparable.

Mick Richards

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20 hours ago, Dave McDonald said:

I've just had my TR5 block line bored for camshaft bearings. That and all other machining should be compete this week for me to collect.

I supplied my new cam to the m/c shop and they supplied and fitted the shells. The work is being done at Stanwood Engineering in Bawtry, South Yorkshire. No connection, but I have been very pleased by the workmanlike manner in which they have kept me informed of progress as the work has gone on.

I don't pretend to be an expert. However, I wouldn't have thought the specific dimension from centre line of crank to centre line of cam would be that important, as long as the cam bearings are within the original bores and crank and cam are parallel to each other. If it was different to the original any deviation, which would be very small, should be taken up by the timing chain tensioner.

Dave McD

Dave

Stanwood as a small engineering company are as good if not better than any you will find I have used them since I was 20 years old, Then they did have to contract balancing to outside party's but that was quick turn around. I took Stuart there many years ago along with a visit to Longstone's tyres that was a fun day, are you going to get the parts balanced ? well worth it imho.      

Edited by ntc
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1 hour ago, ntc said:

Dave

Stanwood as a small engineering company are as good if not better than any you will find I have used them since I was 20 years old, Then they did have to contract balancing to outside party's but that was quick turn around. I took Stuart there many years ago along with a visit to Longstone's tyres that was a fun day, are you going to get the parts balanced ? well worth it imho.      

Neil,

Yes, the crank, damper, flywheel and clutch cover have all been balanced, initially separately then checked as an assembly. Also the pistons and new Maxspeed steel rods have all been balanced. Stanwood had to outsource that but it was done quickly as you say. Stanwood rang me today to let me know it should all be ready to collect after tomorrow.

Slight worry, they told me the balancing bloke reported that he noticed that the brand new damper, bought from "one of the well known parts suppliers," had a visible "bob" on it. He has been able to balance it but had to drill 3 significant  holes close to each other to achieve that. I will check it for "roundness" on the crank with a dial gauge when I get it back. If I'm not happy I'll ask for a replacement. The fact that it was balanced separately from everything else should enable a new one to be similarly balanced without upsetting the balance of the whole assembly. I only bought a replacement because I wasn't happy with the appearance of the rubber on the original 52 year old unit. Why can't the manufacturers get it right - it's only two discs of cast steel with moulded rubber between them.

Dave McD

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19 hours ago, Motorsport Mickey said:

AAaaaahhh our old friend the hand driven Symmetrical align boring tool, is that yours Andreas or did you just get used to it at where you work ?

Mick Richards

Oh, that is an very old milling machine I got from a machine shop.

The head can be turned 90 degrees for line boring in x-axis.

The advantage is that the table has a pretty long travel table in x-axis.

It can also mill a TR6 cylinder head perfectly.

 

2122091276_SkimmingHead01.jpg.c7f2436ddc4f74cc948bca9d84a0540f.jpg

Edited by TriumphV8
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I do balancing on all parts by myself.

The best pulley will not help if the fan is not properly balanced.

In my opinion it is not necessary to balance out the last 10th of a gram

but have all in limits, especially the clutch cover, front extension and fan.

 

This is a pulley prepared to accept the triggerwheel for EFI fuel injection.

It is simply balanced by gravitation.

 

849776555_WuchtenSchwungscheibe03.jpg.4059866fb5275eb16801d2df7d1f760c.jpg

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Andreas is an artist and understands machining better than many of us (me).
Keep posting!

Waldi

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3 hours ago, Waldi said:

Andreas is an artist and understands machining better than many of us (me).
Keep posting!

Waldi

So sweet! Many thanks but this time the balancing unit is from Apfelbeck:

Apfelbeck.png.780a2afa0d8e1acf6043ee61eb07321d.png

Unfortunately in a funny language but anyway worth to read (and understand)

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