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[Bernhard]

Hi.......did you see the new ball berings from Graham
 
Ball bearing version of our TVR1A. Four (4) shielded ball bearings replace the brass sleeve bearings on the crankshaft/base assembly resulting in much lower friction as well as fewer parts to wear over time

photo from another forum...

[essex2visuvesi]

Looks like it would be fairly easy to retrofit into the non BB version.

[kno3]

Not really, because the bottom part that holds the ball bearing is cast together with the base plate. I guess you either have to make new bottom bearing holders or purchase the new base plate as well.

[essex2visuvesi]

Ah right.... not just a case of pushing out the old bushing and replacing with the BB then?

[kno3]

Unfortunately no. You can see what the new (cast?) aluminium base looks like here:
http://www.rcgroups.com/forums/showthread.php?t=1336233

[essex2visuvesi]

interesting.....

by the looks of things it should be easy to retrofit with a new baseplate, bearings and holders..... Wonder if they will do a kit?

[Reg Hinnant]

I posted a few more pictures of the BB build on http://www.rcgroups.com/forums/showthread.php?t=1336233#post16574935

[Reg Hinnant]

Finished BB version (with several modifications) ready to start run in.

[kiwimodeller]

It will be interesting to hear from Reg as to how it goes. Has anybody done a comparison between the standard bushed engine and the ball bearing one? There does not seem to be anything on the Graham website yet to tell us why the change was made but it looks as if both types will still be available. Cheers, Ian.

[derekwarner]

Ian...one of the issues to be considered here is the method  of build of the bottom end crankshaft 

Easy to install a small ZZ stainless ball bearings at each end of the crank.....but how are they installed at the inboard intermediate journals?   ....fabricated crank construction?

JMC nominates small ZZ stainless ball bearings for the crank for engines up to 3CC .....then nominates bronze bushes for the next engine sizing of 5CC

Nick from Monahan nominated small ZZ stainless ball bearings for the crank for his engines .....

We have a few elements to consider  in how they achieve

alignment, cleanliness, rotational timing, lubrication...lack of or TOO much...then a few fundamentals like cost efficiencies in manufacture....   .....I certainly do not have the answers to these questions....Derek

[Circlip]

Another poorly added "Mod", generated to catch the unwary into shelling out more than they understand they need.

 There ain't NO support to the centre of the crankshaft ie. between the cranks where most of the "Force" is applied.

 They have fully supported the eccentric (BIG DEAL) from thrust loads with a bearing on either side cos ALL the bits slide on the shaft ends.

 Sad when you see manufacturers with sound engineering principles hit the wall (Like Nick M) when glister merchants fool the populace with what some think to be Essentials that only add to price and not efficiency.

  "A fool and his money" spring to mind, methinks there is a foul smell eminating from Denmark.

  Regards  Ian.

[Reg Hinnant]

Hey Circlip, I have a few relatives that will agree with you about "A fool and his money" buying "toy" engines that are not essential in any way much less being serious about them. 
Tell me what one of Nicks engines (same style) would have cost?

[gondolier88]

Another poorly added "Mod", generated to catch the unwary into shelling out more than they understand they need.

 There ain't NO support to the centre of the crankshaft ie. between the cranks where most of the "Force" is applied.

 They have fully supported the eccentric (BIG DEAL) from thrust loads with a bearing on either side cos ALL the bits slide on the shaft ends.

 Sad when you see manufacturers with sound engineering principles hit the wall (Like Nick M) when glister merchants fool the populace with what some think to be Essentials that only add to price and not efficiency.

  "A fool and his money" spring to mind, methinks there is a foul smell eminating from Denmark.

  Regards  Ian.

Hi Ian,

In an ideal world the 'shaft would be supported between the central webs, however close inspection of the second pic posted by Bernhard shows that the shaft is machined from solid and that the two webs are joined by a section with support to the ends of each web. This is still a very strong shaft, and with the low output of these engines taken into consideration I can't see problems arrising- only time will tell I suppose.

One thing I really can't understand is WHY  doesn't anyone with a TVR1 paint the aluminium bits?

Greg

[Reg Hinnant]

Hey Greg, Kmot did but you can hardly tell since he painted all of the alum parts "Hammertone Silver"
http://www.rcgroups.com/forums/showthread.php?t=1333359&page=4

I would have loved to find someone to anodize all of the alum parts but could not find anyone who would take small quantities.
I did the steam chests & cyl covers with chemical blacking.

[HS93 (RIP)]

Hi Ian,

One thing I really can't understand is WHY  doesn't anyone with a TVR1 paint the aluminium bits?

Greg

I was thinking of doing one but replace all the  aluminium bits with brass, still a very cheap engine and a way for people to get in to steam with a Mack steam boiler.

Peter

[kno3]

Finished BB version (with several modifications) ready to start run in.

I'm glad you chose to shape the cylinder support plate, it gives the engine a much sleeker (and real-life-like) look.  And the black painted bits look nice as well.
You should try painting the base too, perhaps another colour.

[Reg Hinnant]

Quick up date,
I have run the engine on air and it runs great.
I did try to pay close attention to the valve timing and I believe it paid off due to how well it ran from the beginning. After a few hours it would even run at the notch next to the center position.
As for the ball bearing version, I have only had bindings from the eccentric strap rubbing against the BB housing. I found that you need to move both the eccentric cams (53076) to the outside of their position on the shaft. Then I have added a thin washer behind the slide assembly T slot (A2014) on each side. This is to keep the Eccentric strap (53075) away from the center ball bearings housings on both sides and to get the eccentric strap to run true on the eccentric.
I do not believe the standard bearing models have this clearance issue.
All in all, I am very happy with this engine for the price.