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Tenshodo V Black Beetle

Posted: Fri Apr 18, 2008 5:45 pm
by bluey1989
Hello all

I have just purchased a 31mm WB Tenshodo on ebay, excepting a good running motor bogie to go under a black dog firefly loco.
However, I dont think I have seen anything run so bad (even the old hornby locos could give it a run for its money). I was that shocked I contacted a friend and he said he had one but never run it, thats was just as bad. Its it ok at a scale speed of 100mph and you need your ear defenders on its that loud.

How does the black beetle motor bogie compete with this (I want a slow running quiet motor bogie, is this too much to ask for???)
How different in size is it compared to a tenshodo? My firefly loco is for a tenshodo.

Cheers,

Andy

Posted: Fri Apr 18, 2008 7:02 pm
by Steve Bennett
I think you just found out why it was on Ebay Andy.
From your description it sounds like the gears on the axles are split and not meshing properly, which would explain the noise and poor running. Would also explain why it needs to be run at speed, though it wont for long before the plastic gears on the axles disintegrate completely. New gears will probaby transform it. In good condition, a Tenshodo is normally very quiet, though they do growl a bit when used with a feedback power supply.

noisy tenshodo

Posted: Fri Apr 18, 2008 7:31 pm
by b1gy1n
Andy,i had one that went the same,and i replaced the gears with ones from Branchlines,it might be worth giving them a bell to see if they can help.

regards Marc

Re: Tenshodo V Black Beetle

Posted: Fri Apr 18, 2008 7:40 pm
by Gerry Bullock
monstermunch1982 wrote:
How does the black beetle motor bogie compete with this (I want a slow running quiet motor bogie, is this too much to ask for???)
How different in size is it compared to a tenshodo? My firefly loco is for a tenshodo.

Cheers,

Andy


I'm unable to comment on the Tenshodo as I no longer use them preferring the BEC that so many decry :!: :roll:
However I do have one Black Beetle that sits underneath Scott's "Skip" Lister. I've just run it over a distance of 780mm, time taken 40 seconds, it will run slower BUT not consistently so that's the benchmark as far as I'm concerned.
My BEC Tractor Loco can only achieve 20 seconds for same distance, any slower and it stops.
My Crapper Critter powered by a GE44 bogie takes 35 seconds for same distance, might just go slower but not too consistent.
My VB Bachmann Percy takes 27 seconds for the same distance (not run-in).
I can beat the Benchmark BUT at a price :lol: :lol: the Mashima powered Effie (Scratchbuilt kit :wink: ) will take as long as 55 seconds for the trip.
If you search archives you'll find all of these Locos appear in one or more threads.
I should add that the Black Beetle had to be returned to Oz as it stripped one set of gears after only about 30 seconds running however I understand that that is a tad unusual.

Posted: Fri Apr 18, 2008 7:52 pm
by Gerry Bullock
I should have added that a Bachmann Trolley (new bare unit) also achieved a time of 35 seconds running much slower than some Videos I've seen recently from tuther side of Pond. :shock:

Posted: Fri Apr 18, 2008 9:02 pm
by Bob Taylor
Andy,

Try adding some weight. Mine was purchased brand new and ran poorly until I added weight. Worth a go.


Bob.

Posted: Sat Apr 19, 2008 2:44 pm
by docnjoj
This sounds like a contest!? Gerry, what are U using for a power supply? Is it feedback?
Doc

Posted: Sat Apr 19, 2008 3:24 pm
by Gerry Bullock
docnjoj wrote:This sounds like a contest!? Gerry, what are U using for a power supply? Is it feedback?
Doc

No Doc, it's an ancient Gaugemaster handheld controller with a broken wire in max speed circuit (which as you'll have gathered is irrelevant on my layouts). Fed from a home made transformer, no idea what's within - made by Club's electriconics whizz-kid.
If you've noted previous posts track Gnever cleaned just rubbed with a graphite pencil.

Posted: Sat Apr 19, 2008 3:37 pm
by Steve Bennett
Gerry Bullock wrote:No Doc, it's an ancient Gaugemaster handheld controller with a broken wire in max speed circuit (which as you'll have gathered is irrelevant on my layouts).


If it is an old Gaugemaster handheld unit, then I think you will find that it is a feedback controller Gerry. I dont think that Gaugemaster introduced a non-feedback handheld until fairly recently, I could be wrong though :wink: .

Posted: Sat Apr 19, 2008 3:51 pm
by docnjoj
Gnever cleaned, just rubbed! Sounds like James Bond! I am planning to get an MRC Tech 4, as this seems the only American made one at a reasonable price w/feedback! Tried to get a Kent, but they Gnever wrote back!
Doc

Posted: Mon Apr 21, 2008 12:31 am
by Prof Klyzlr
Dear Andy,

Sorry for the late reply, but Tenshodo PDTs/SPUDs have 14:1 ratio gearing, and are very light.

The "stock" black beetle is the same ratio, but is better engineered IMHO.

However, for NG work, the best move IMHO is the 27:1 ratio Black Beetle. Better gear reduction, relatively quiet, and pulls well with a decent weight body on top.

http://home.waterfront.net.au/~sem/bbeetle.htm for mor info...

Posted: Mon Apr 21, 2008 1:07 am
by trainbuilder
Prof Klyzlr wrote:Dear Andy,

Sorry for the late reply, but Tenshodo PDTs/SPUDs have 14:1 ratio gearing, and are very light.

The "stock" black beetle is the same ratio, but is better engineered IMHO.

However, for NG work, the best move IMHO is the 27:1 ratio Black Beetle. Better gear reduction, relatively quiet, and pulls well with a decent weight body on top.

http://home.waterfront.net.au/~sem/bbeetle.htm for mor info...


Hi Guys,

reading all the issue related to the Tenshodo Spud, the Black Beetle and various other self contained power units it seems to me that perhaps we should start a new topic series on Custom Building Chassis and Powering Models.

The running characteristics of any good model are based on 3 simple factors:

- Proper consistent power collection from the rails;
- motor efficiency and:
- Gearing, gearing and more gearing.

Unless these factors are present it is unreasonable to expect slow running operation.

to illustrate this point all my models are geared to 240:1 as a MIMIMUM to ensure protoptype top speed at maximum voltage. Sometimes the gearing is brought to even higher ratios in models such as the Listers or Simplex to achive a prototype operational speed.

The use of Faulhaber and similar gearhead motors are a prerequisite for good operation. Contrary to common belief these can be bought at bargain prices for as low as $US10.

If there is enough interest I am happy to chair the Chassis Custom Building topic.

have fun and above all stay cool
Trainbuilder

Posted: Mon Apr 21, 2008 1:15 am
by Prof Klyzlr
Dear Trainbuilder,

Points well taken,
(and often forgotten by those who expect DCC to cure all their locos electro-mechanically based ills! :roll: ).

However, if I may ask a question,
what is your opinion of the NWSL "school of mech design" thinking,
which essentially says

"...excessive high ratios/lots of gears = lots of rotating stuff to wear out,
and lots of individual parts that cumulatively add operating noise to the mech,

whereas a well-chosen high torque/low rev can motor,
+ a modest gear ratio (1:20 - 1:40 or so),
should give good low speed switching control,
minimal operating/mech noise,
and low "drivetrain component count", thus less parts to wear out..."?

I'm basing my previous comments RE SPUDs VS BBs on "hands-on" testing betwen the units involved,
inc head-to-head "under show condition" testing of the 14:1 and 27:1 BB's...

and these units are by no means equipped with the 240:1 style ratios you are mentioning...

I'm intriguied! ;-)

Posted: Mon Apr 21, 2008 1:31 am
by trainbuilder
Prof Klyzlr wrote:Dear Trainbuilder,

Points well taken,
(and often forgotten by those who expect DCC to cure all their locos electro-mechanically based ills! :roll: ).

However, if I may ask a question,
what is your opinion of the NWSL "school of mech design" thinking,
which essentially says

"...excessive high ratios/lots of gears = lots of rotating stuff to wear out,
and lots of individual parts that cumulatively add operating noise to the mech,

whereas a well-chosen high torque/low rev can motor,
+ a modest gear ratio (1:20 - 1:40 or so),
should give good low speed switching control,
minimal operating/mech noise,
and low "drivetrain component count", thus less parts to wear out..."?

I'm basing my previous comments RE SPUDs VS BBs on "hands-on" testing betwen the units involved,
inc head-to-head "under show condition" testing of the 14:1 and 27:1 BB's...

and these units are by no means equipped with the 240:1 style ratios you are mentioning...

I'm intriguied! ;-)


Hi Prof,

you are entirely correct insofar that gear noise can be a problem. However perhaps you have not considered that one of the greatest techniques, particularly for our beloved industrial models, is the combination of:

- precision gearhead motors for the initial stage up to [say] 50:1
- use of friction drives for the subsequent stages using neoprene rings on grooved discs and small diameter posts
- or the use of timing belts for the final stages.

I have just completed a Simplex Bow Frame to absolute scale, with gearing at 380:1 which not only runs at phenominally slow speeds, but is absolutely silent.

The 15X12mm 9v motor has a 48:1 gearhead. This assembly is totally concealed and has allowed a dummy motor under the hood as well.

hope this helps

Have fun & stay cool
trainbuilder

Posted: Mon Apr 21, 2008 8:04 am
by docnjoj
Got to agree that more gear reduction means better running. My beloved Grandtline stuff goes between 80:1 and 160:1 and runs really slow. Grandt uses nylon gears (and I believe so does the Micro-mo powered Porter) although it has a flywheel in the gearhead. They are a bit noisy, but that is part of the Mystique and Charm! Micro-mo gearheads and motors are superb, but expensive and hard to get in the USA.
Doc

Posted: Mon Apr 21, 2008 11:32 am
by Steve Bennett
Prof Klyzlr wrote:whereas a well-chosen high torque/low rev can motor,
+ a modest gear ratio (1:20 - 1:40 or so),
should give good low speed switching control,
minimal operating/mech noise,
and low "drivetrain component count", thus less parts to wear out..."?


Have to agree with the Prof here. Have been down the super high ratios route and dont find the practical controlability an advantage. In fact, I find the lower ratios easier to use on a small layout and feel they give more realistic running, not to mention you dont get the noise of a demented bee from the motors or the whirr of the gears sounding like they are trying to put the loco into orbit.

The best slow speed runner I have is a BEC tram unit with 18:1 gear ratio. The controller can be set nice and low and it will move along the track at such a slow speed, you cant see it moving and with the body removed from the loco, you can count the revolutions of the cheap open frame motor. On a 20 inch long layout that I have, it takes more than 5 minutes to get from one end to the other and that includes climbing onto far from perfectly aligned traverser. Of course there is no practical use in running this slow, but it is good to know it can do it.

Dont forget, the controller you use is just important as the motor and gear ratios, not to mention the track surface. It is getting all the elements to work in harmony that is the difficult bit.

Posted: Mon Apr 21, 2008 8:15 pm
by Glen A
Steve Bennett wrote:Dont forget, the controller you use is just important as the motor and gear ratios, not to mention the track surface. It is getting all the elements to work in harmony that is the difficult bit.


Ok, so what is the best (or a good) feedback controller that you recommend :?:
I got a tenshodo spud unit. I ran it in. And I added weight. And I checked the wheels and track was clean.
After getting it moving at high speed I can slowly drop the speed back to something close to acceptable. BUT I can't just slowly accelerate away from stopped. :cry: So I wrote them off as a waste of money, and bought up some Bachmann Gas mechanicals, which were cheaper and ran better. :P
After just finishing the body for the tenshodo, I am considering buying a better controller to run it, (and the other cheap hornby locos waiting for conversion).

Posted: Mon Apr 21, 2008 8:36 pm
by docnjoj
Yeah, me too. I havent bought a power pack in about 8 years, so the Tech4MRC looks like the best I can get for the money! It has feedback at low voltage and can be gotten for $40 plus shipping in USA.
Doc

Re: Closed loop feedback controllers

Posted: Mon Apr 21, 2008 9:17 pm
by cp409067
***

Posted: Mon Apr 21, 2008 10:58 pm
by trainbuilder
Hi Gnatterboxers

interesting debate.

In response to the question about controllers the answer is quite simple. any controller that will deliver a good electrical wave characteristic will provide speed control to a motor and operate it within the design characteristics of the motor. This is why even very old H&M controllers work fine, or my self designed Darlington pair transistor based controller, which is designed to maximise coreless motors and costs about $20.

The real issue in speed control and the slow speed performance does not rest with the controller [as a broad general statement] but in the performance of the chassis [or the PDT as the case may be]. If the chassis/motor/gearing combination is not up to scratch even the most costly controller or DCC system cannot make the model perform.

To illustrate this point I have just completed a new Simplex Bow Frame, which is geared at around 340:1 and fitted with a coreless motor that is even at this early stage able to consistently pass through one metre of curved test track at 110 seconds using my home-built controller.

The reason why some of the very cheap chassis work well is due to the right combination of motor/chassis/gearing as is the case in the Bachmann On3 diesel.

Some of the members indicate that they can get their models to operate OK once they are slowed down from a jack rabit start. This is again due to the combination of poor gearing linked to binds in the mechanism and [usually] a 20 cent motor.

I truly recommend that we start looking at the core issues of the combination of factors that cause poor operation before going out to buy expensive controllers that in themself cannot solve the problems.

As I said I am happy to start a clinic on this in the discussion board if there is enough interest.

have fun & stay cool
trainbuilder [/b]

Posted: Tue Apr 22, 2008 8:30 am
by AndyA
All advice gratefully received. I'm happy with the SPUDs I've got, but it took a long time to get a 'skirt' (like Steve B's chassis and in fact mine's almost identical in size to Steve's "Tiny" chassis) with the right weight to match the SPUD and my bog-standard Gaugemaster controller.

I'd also be interested in a clinic from folks who've built chassis using neoprene ring drives. I'd always discarded the idea 'til I saw some professional ones at Swanley: looks like something I might be able to manage, with a little help.

regards
Andy A

Posted: Tue Apr 22, 2008 6:34 pm
by Gerry Bullock
As one who uses, successfully, 20c motors with excellent results and who has been with Gn15 for 5 of its 6 years I think Gnewbies might like to consider the unwritten ethos of the scale - KISS. Certainly that's what many Gnatterboxers have advocated, if not verbally, in their modelling efforts that have appeared in this forum.
How slow or not a Loco can operate is often irrelevant as I had confirmed last Sunday whilst showing Gneiss Farm. During the afternoon when all my Loco motors were well warm I rechecked how slow they would cover the visible length of the layout. I'll mention BUT one - the Skip Lister, powered by a Black Beetle with 27:1 gearing, 2 minutes 6 seconds (if you recall the distance was 780mm).
Did I have any witnesses, not for long; those watching got fed up and walked away.
Complex systems don't interest me and I'm sure I'm not alone! What better than buying a cheap, off the shelf item and bashing it to one's satisfaction.
If I want something more complex (Brass kits for example) I like many others have to find a builder to construct the gem.
One only has to look at Christopher's 1/25 scale Show Layouts using cheap Hornby power units to realise that extremes are unnecessary to produce superb and entertaining displays.

Posted: Tue Apr 22, 2008 8:17 pm
by Glen A
Gerry Bullock wrote:How slow or not a Loco can operate is often irrelevant as I had confirmed last Sunday whilst showing Gneiss Farm. During the afternoon when all my Loco motors were well warm I rechecked how slow they would cover the visible length of the layout. I'll mention BUT one - the Skip Lister, powered by a Black Beetle with 27:1 gearing, 2 minutes 6 seconds (if you recall the distance was 780mm).
Did I have any witnesses, not for long; those watching got fed up and walked away.

One only has to look at Christopher's 1/25 scale Show Layouts using cheap Hornby power units to realise that extremes are unnecessary to produce superb and entertaining displays.


Gerry,

I totally agree with your comment about Christopher’s locos. Really nice! And I took great inspiration from his locos, and started down the same path, with bashing some cheap Hornby locos too. But for me there is little point spending lots of time building a really nice loco, if it won't run reliably (at an exhibition). Because you can't use it.

And I take your point about running so slow that people get bored and walk away. But I also think many layouts are spoilt because they have slot cars with train bodies running on them.

Posted: Tue Apr 22, 2008 8:40 pm
by Steve Bennett
Glen A wrote:[I totally agree with your comment about Christopher’s locos. Really nice! And I took great inspiration from his locos, and started down the same path, with bashing some cheap Hornby locos too. But for me there is little point spending lots of time building a really nice loco, if it won't run reliably (at an exhibition). Because you can't use it.


Unfortunately with your geographical location Glen, you wont have had the pleasure of being able to watch Christophers layouts run. I'm fortunate and have spent many hours over the last 15 years or so, watching them operate and they are a pleasure to behold. Many who see them dont believe that there are simple Hornby mechanisms hiding underneath, but there are and they perform admirably. So well, that once you get absorbed in the operations, you dont even think about what makes them work :) .

Posted: Tue Apr 22, 2008 9:03 pm
by Glen A
Steve Bennett wrote:Unfortunately with your geographical location Glen, you wont have had the pleasure of being able to watch Christophers layouts run.


Yes I really would like to see it. And Gerry's salt works. Who knows, one day I might make it over...if my wife wins lotto.