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Hi Guys

 

I've been HO scale for more years than I care to admit, and now I'm having a go at O.

 

So this is my first topic - as much to see how to drive the forum as anything else.

 

Toe in the water time - I bought an Atlas SDP-35 and a Weaver GP-38.

 

I'm not sure how to drive the photo gallery, but here goes . . .

 

 

 

Anyway, I've tarted up the Weaver with hoses, bell, cut levers and windshield wipers.  All good.

 

The loco ran poorly at low speed, so I put an idler on the chain to stop it from lashing.  Beautiful!

 

 

 

Except for a loud, moaning sound coming from the Pittman motor.  The only way to stop it was to turn off the BEMF in the Loksound decoder.

 

Not an ideal situation.

 

So, my question is, are all Pittman motors like this - or did I just get a dud?

 

If they are all poor quality, what should I change it with?

 

I've uploaded the photos but I can't insert them into the spaces in the text.

 

Not bad for a first attempt. 

 

Cheers

 

 

OL 01

OL 02

 

 

 

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Original Post

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Those Pittman Cans are super motors in my opinion.    Similar models of Pittmans used to be in many computer printers.   They would last for ever and even then you can salvage the motor when the printer wears out.

 

It might be something about the signal from that decoder, or even maybe it is set in "switching" mode and sending a modified DC signal that is pulsating.   

 

You get annoying humming when you run straight DC locos on DCC power.    So maybe the decoder is not passing on straight DC to the motor.

Max, which model of Loksound decoder are you using?

 

Also I have not found the need to add an idler on stock Weaver drives, but every Weaver Pittman drive I have seen had cracked sprockets causing very rough running and high load on the motor each time the crack comes around.

 

I use most of the tips and tricks here for smooth running:

https://bobsobol.smugmug.com/T...018664&k=jxLWMHq 

 

HTH    

 

Pete

 

 

Last edited by Pete M

Hi Pete

 

I'm using a Loksound Select.  A commonly used decoder by members of the Loksound group, for O scale locos.  I've also used V 4's, but not this time.  I record my own sounds and make sound projects, so I'm very experienced with them.

 

I'll be very disappointed if it has cracked sprockets, as it's new; straight out of the box.  I'll tear it down and have a look anyway.

 

Thanks for the link.  I'll have a look.

 

Is there anywhere I can get help with my earlier question about the photos?

 

Cheers

 

 

Originally Posted by Simon Winter:

There is a guy who goes by bob2 on the forum that knows quite a bit about Pitmans. Some are better suited than others. Hopefully he will turn up.

 

Simon

Hi Simon

 

That guy could be the one in Pete's link.  I had a look at it.  Lots of good info there Pete.  If/when I sort the BEMF issue, I'll be having a closer look.

 

Cheers

To answer your question about photos, try this.  Within your posting box, type a little info and then add an attachment here, being sure to check the box so that all pictures are added within text before completing that upload.

IMG_8233

Then, type a little more info and choose to add another attachment, doing all the same things you did for the first attachment.

 

IMG_8244

After each attachment upload, you have to remember to check the box about inserting photo or video into the text of you message, and then click the "Finished" box which puts the picture into the message and takes you back to the Post Message or Post Reply screen.  Then, hit your keyboard "Enter" key and add more text as you choose.  Finally, remember to scroll down to the bottom of the Message or Reply box and press "Submit," and your info should look like above.

 

I used some pictures of our 30th anniversary vowel renewal in Hawaii last October to demonstrate.

 

Chuck

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Hi Max,
 
Not the same Bob. Both are very knowledgeable. Bob Sobol more on the Diesel modelling side from what I've learned online. I have also learned a lot about Pittman motors from 2 other experts: Jay Criswell and Rod Miller. 
 
For example I learned that earlier Pittmans used Alnico (conventional) magnets. Later models used modern Neodymium magnets. I can speak from my own experience that the older ones are current hogs, the newer ones much more efficient. As I recall, the Alnicos have a "1" as the third digit in the model number e.g. 8514 as found in many Weaver drives. The rare earth magnet ones have a "2" as the third digit.
 
I have been frying decoders in O scale since 1994 but I only have 1 Loksound. I have been working with Digitrax and then NCE with DSX sound added, then recently Tsunamis and now TCSWOWsound. So much to learn! 
 
The gears Weaver used were made a long time ago and were a press fit on their shafts. They crack as the plastic shrinks. This happens anyway, even if the loco was never out of the box. I have 7 Weaver drive sets (some in other brands of engine) and all top sprockets were cracked when I got them, and several bottom sprockets too.    
 
Re the humming, I am trying to say that the cracked gears may be causing it. if the Loksound works by adjusting PWM to attain constant speed, then the cracked gears are loading up the drive several times per wheel revolution. Then if the Loksound drops the PWM frequency way down into audible range to try and generate enough torque to overcome the gears, that's when you get the hum.
 
If the top sprockets are cracked it's happening several times per wheel revolution as the gear reduction happens at the axles on a stock Weaver drive. 
 
I have an early NCE D408 which has user adjustable PWM frequency. You can take it up to about 16kHz and not hear any motor hum. But the loco wouldn't pull the skin off a rice pudding! Turn the PWM down to a few kHz and it will pull the side off the building. But it hums so loud it's unbearable.
 
Is your DC setup smooth power or pulsed?
 
I may be way off base here as I don't know how the Loksound works, but just in case it helps, I really would check for cracked gears first. You can do that easily just by taking off the shell and manually turning the driveshaft from the motor. You'll feel a hard "notch" every 1 turn of the drive shaft, and see the chain climbing out of the sprocket each time as the teeth each side of the crack are too large a pitch.
 
HTH
 
Pete 
 
 
Originally Posted by MaxSouthOz:

Hi Pete

 

I'm using a Loksound Select.  A commonly used decoder by members of the Loksound group, for O scale locos.  I've also used V 4's, but not this time.  I record my own sounds and make sound projects, so I'm very experienced with them.

 

I'll be very disappointed if it has cracked sprockets, as it's new; straight out of the box.  I'll tear it down and have a look anyway.

 

Thanks for the link.  I'll have a look.

 

Is there anywhere I can get help with my earlier question about the photos?

 

Cheers

 

 

 

Last edited by Pete M

Max,

I am not running decoders I just running a remote control that basically is a decoder made by GML.

Crack gears will make hesitation at any speed, but more noticeable at low speeds.

As peter M say, rotate it manually and also disconnect the drive shaft from the motor and test the motor empty.

 

Andre. 

 

Pleased to help Max. I have a few scars from trying to get these drives to run really smooth over the years, better if the collective knowledge here can save you some of the pain... 
 
Good that your DC is smooth. My guess is it was just delivering more Amps to get you over the load spikes but you wouldn't know that audibly, you'd need an Ammeter to tell.
 
Good luck with your explorations!
 
Pete
 
 Originally Posted by MaxSouthOz:

Thanks, Andre.

 

At least I will know what to look for, now.

 

I'm off to do some surgery. 

 

Cheers

 

The locomotive may be new to you but Weaver quit making that horizontal drive about 15 years ago so not really new.  My guess is that PD Hobbies http://pdhobbyshop.com is now the owner of that drive mechanism as they have been selling and supporting it ever since.

 

The idler idea has been around for a long time for the reasons you cite and it would be nice if Pat @ PD would make one available, but not so far.

Last edited by rdunniii

"I'll be very disappointed if it has cracked sprockets, as it's new; straight out of the box."

 

  I'd be surprised if it doesn't have cracked gears. Unless someone has changed them it's almost a certainty. Get replacements and learn to install them is the normal solution. These drives are very easy to troubleshoot and repair.......DaveB 

Originally Posted by rdunniii:

The locomotive may be new to you but Weaver quit making that horizontal drive about 15 years ago so not really new.  My guess is that PD Hobbies http://pdhobbyshop.com is now the owner of that drive mechanism as they have been selling and supporting it ever since.

 

The idler idea has been around for a long time for the reasons you cite and it would be nice if Pat @ PD would make one available, but not so far.

Thanks, I've ordered a new drive and a motor with ball bearings.

 

It's still a cheap loco and it will run well I'm sure, with the new drive.

 

Pat was very helpful by email.

 

Cheers

Well, looks like the loco is covered.

 

P&D is kind of local for me, but one of those shops that I can never seem to catch open. (Wild Bills too).

   In ten years, they've been closed every time I got there, and once I took a day off for it, and they had a slot or RC event going, and I couldn't get in to shop.

  I gave up trying to "catch" them. Good luck.

 

 The photos appear at the posts end, but can be cut and pasted into the text in the right spot.

 As you click on the photo, white parameter boxes will show, now cut and paste it to a new spot.

 If you don't check the "appear full sized in test", then they will only show as attachments at the bottom.

  Click the attachment options at the post bottom if you change your mind, or if you wanted a smaller version of the photo to appear(there are size choices there).

  Embed video with the "film strip" at the top.(You tube adds some code on occasion. Anything in front of "http" should be erased from the url or you will see the OGRF page in the preview instead, and it wont work.   

  

PeteM said everything I would have said.  Pay attention to the motor number - the rare earth magnets are a significant improvement for two bucks more - and Pittman still sells the Alnico motors! 

 

Weaver cheaped out in two places - first, with motors, and then with non-aged plastic.  Using an Alnico motor with solid bearings in an application where radial force is applied is a no-no.  Charlie pIttman Jr. told me that personally.

 

Aging the plastic before machining is why NWSL and CLW gears rarely split.

Hi Pete

 

I haven't disassembled the tower, but visually inspecting the sprockets with a super bright LED torch, shows no cracking in the sprockets.

 

Turning the drive by hand, it looks as though the teeth might have some rough edges, as the chain links look like they are catching on them.

 

When I had this problem with the P2K HO locos, often it was necessary to take the gears off the axles and force the cracks open using an O ring pick, before you could see them.

 

I really don't want to strip the drive until the kit arrives, so I might see more during the rebuild.

 

I hope that you can cope until then. 

 

Cheers

I'll keep taking my meds and hope to pull through...

 

On a more serious note, I did wonder f I saw a roll-pin through the top sprocket in your first picture. Maybe it's an "improved" version if so?

 

Also, I have found 3 other things that seem to apply to all my sets, based on Bob Sobol's excellent work.

 

  1. The centre lines of the top and bottom shafts are not parallel. The top shaft's boss seems to have been angled down a little in the tower design. This causes the chain to always be pulling at an angle to the teeth, no matter how well you align top and bottom sprockets. Definitely a cause of constant hum/noise. 
  2. The sprocket boss is too narrow on one side. This means the chain sticks out beyond it and rubs on the washers supplied. Definitely a cause of constant hum/noise. Bob S made some top-hat washers to create clearance - see his pics on Smugmug. I don't have his skills and equipment, so I use sleeves cut from brass tubing between the sprocket boss and washer.  
  3. Some replacement sprockets are cast not machined, and have the mould halves mis-aligned so the teeth are too wide for the chain. I don't think you have this issue though.

Apart from that, it's a great drive system!    

 

Cheers,

 

Pete

Last edited by Pete M

Hi Pete

 

Thanks for all of that.  I expect the kit to arrive this week  P&D are not great communicators, so I'm watching and waiting.  I'm used to that in South Oz.

 

I'll sit down with all your advice points and hopefully make a good fist of it.  Having an engineering background, I agree with your assessment that it is potentially a good drive.

 

In the meantime, I'm plugging away building my new layout, so I'll have somewhere to run it. 

 

 

PE 20

Cheers  (I hope the photo works)

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Just an update, so you know I'm still alive. 

 

I ordered the drive kit from P&D on August 19th, but so far it hasn't arrived.  Pat is working on it from his end, as well as me from mine - but after all this time, I think it's lost.

 

Pat has offered to send me a replacement.  I think that's the way it will end up going.

 

Good service.

 

Cheers

Hi JPV

 

The scenario is a waterfront with an ocean going tug boat moored to the dock.  I'm thinking of doing a thread on it as I build it, but I've wanted to watch others to see if that would be appropriate on this forum; before I attempt it.

 

Oz is what we call Australia,  so I'm in South Australia - right down at the bottom. 

 

Cheers

Hi Max,

 

Sorry to hear about the lost drive. Pat is a great guy and will look after you I'm sure. I have had nothing but great experiences with P&D over 20+ years.

 

I recently found another upgrade to the drive towers that gets rid of the down-slope of the top shaft and adds double ball-bearings to it. It also provides an adjustable-height tower to achieve perfect chain tension with any sprocket combination.

 

I don't think it's allowed to post their URL here, so PM me if interested. The parts just arrived so I'll post some pics once I get into the job.

 

Pete

Thanks, Guys.

 

I've kept progressive photos as I've gone, so it should be easy enough.  SWMBO is off to the Dragon in Law's this arvo (Sunday), so I'll have a go at it when we get back from taking the dog to the beach.

 

Thanks, Pete.  Yep.  I think I've bookmarked that product as well.  Pat's been very helpful.  I didn't want to ask him to send another one until we've exhausted all other possibilities; but it's looking like it might have to happen.

 

The layout will keep me busy in the meantime. 

 

Cheers

Well, Pat and I have been working at this for a while now without finding the lost parcel.

 

Pat has sent me another kit FOC, which arrived today.  I've agreed to return the first one if it ever shows up. 

 

Great service, Pat.     

 

In the meantime, we're still looking.

 

I'm away with the band on a road trip until next week, so I won't get a crack at it until then.

 

I've been plugging away on the layout in the meantime . . .

 

https://ogrforum.ogaugerr.com/t...73#44510795592058273

 

I love playing Bluegrass, but I can't wait to get back to modelling. 

 

TTFN

OK.  Here we go - after a hiatus.    Pat was very good about the lost kit and sent me another one straight away.  Would you believe it?  A couple of weeks later, the first one turned up.  I've sent the spare one back, before anyone asks. 

 

Anyway, I've checked the Weaver tower and the sprockets have no cracks.  What happens, is that the chain hangs up on the teeth end then jumps as it releases - in both the Weaver and the P&D!

 

Here they are, side by side . . .

 

 

016

I had made up a brass idler, which stops the chain wrapping itself around the top sprocket.  That stops the lashing action which was causing jumpy movements in the loco at Notch one.  The P&D one has the wrapping around syndrome as well, so I could change the idler over - or keep the Weaver one.

 

That's what I've decided to do.  I'll have spare sprockets is I ever need them.  The seller gave me a bunch of spare chain, so I'll be OK with all the spares I've got. 

 

Pat  sent me an upgraded motor as well.  The motor in the Weaver was struggling with the Loksound decoder (more like the other way around), so I'll see if the new motor improves things.

 

I've laid 5 metres of track on my new layout, so I'll have somewhere to test it out.

 

Thanks for your interest.

 

Wish me luck.

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Well, I gotta tell ya.  I'm starting to understand why Weaver went out of business.

 

I've replaced the bits as above and the loco runs very well at slow speed, but above notches 1 and 2, the drive train rattles very loudly.

 

The sound of the frequency of the rattle is the same as the tail shaft rotation - but the rattle is coming from the rear drive truck.  I 'end for ended' the square brass shaft, and checked it with a straight edge, but that hasn't helped.

 

The rattle is coming from the rear truck (the one with the chain).  It's nearly loud enough to drown out the sound decoder.

 

Experience tells me that I might need to disassemble the gear boxes between the wheels as there is a lot of play there.  Adding shims might help to tighten it all.

 

A very disappointing product.

P&D replacement to the rescue.  In the box are some spare axle/gearboxes.  Simple process to pop the old one out and pop a new one in.

 

It's reduced the rattling significantly.  Now if I run the sound decoder, I can't hear it.

 

The new motor Pat supplied has improved the decoder performance, but I'm going to have to upgrade to the Loksound L version to get rid of the groaning sound completely.

 

I might set Pat's chain drive up with an idler to replace the old one to see if I can eliminate the rattling completely.

 

Sheesh!  This O gauge lark is a challenge! 

 

Cheers

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