Mainline Build Questions

[adydula]

Ok...

All of th board wiring is complete...will install the boards tomorrow morning....then wait for the resistors to arrive and then we should be ready for the
resistance check and first power on!!!

Getting excited, fingers crossed, and no "smoke"!!..lol

Alex

[adydula]

Just a sanity check...

The 6C45Pi tube socket wiring:

On A1 there are no wires attached to pins 1,3,9
On C3 there are no wires attached to pins 3,6,9

This is correct I assume because 1,3,6,9 are in commom connections for the cathode so your picking the one on each tube that allows for the most direct route etc?

Just checking!

Alex

[AllanMarcus]

Looking really nice! My kit arrives Thursday. I will likely get the top plate powder coated, so a delay for building it for me.

I've never used Tung Oil Finish, but I have used Poly Wipe. Have you used both? How many coats of Tung Oil will you use?

[adydula]

Hi Allan,

I have 4 coats on now, just did the 4th coat an hour ago..it takes 24hrs to dry to use Very Fine steel wool to sand down for the next coat..I was thinking of 4-5 coats.

I will take a good look at it tomorrow in the daylight. It looks very nice right now so this may be it.

I use Formby's Tung Oil, High Gloss, a small pint can, more than enough to do several wood bases.

Its really very, very easy to do compared to other staining I have done....simple 220 at first, then 320 then the first coat...wait 24hrs, steel wool, second coat...repeat until your happy.

Going to mount the boards tomorrow and then wait for the resistors 49.9 ohms and resitance check then power on!

I have taken my time...started last Monday and have worked on it for 4-6 hours a day.


Measured all the parts for values, resistors and caps, measure, cut, strip install!! over and over and over! Ha!! I never thought I would stop wiring.

So far the kit goes together well and if you read the steps a few times its pretty straight forward..but you can get confused if you rush.

Hoping this thing plays the first time!

Good luck on your build.

Alex

[ToneDeaf]

  Good luck Alex.  I want the wood to be a little darker. Went to Lowe's and looked around, and found spray poly with stain in it. I bought the Pecan shade in satin, they had gloss also. Sanded 220, and 320, and sprayed. Didn't darken it much. But it says on the can not to expect muck color on the first coat, and to let the first coat dry for 24 hrs. to seal the wood. Then the next coats should darken a little more. We will see.
  Oh, I got my power cord kit and my two resistors today. You should have yours in no time.

[Paul Birkeland]

Yes, there are a zillion cathode pin connections for the 6C45PI. 

[AllanMarcus]

Wait, did you just use tung oil? No stain?

[adydula]

Allen,

Yes, only Formbys Tung Oil, high gloss....no stain in the product.

It does darken the wood, but not anwhere like a minwax dark stain or other staing products.

I was looking for a more natural lighter finish and an easy method...this one works well...

Several thin coats, dries fast, each day I completed the woring etc I would re-sand and apply anther coat.

The more u apply the more gloss it gets.

Alex

[AllanMarcus]

interesting. thanks.

[adydula]

Ok!

We are done except for the resistors that hopefully will be here on Tuesday....gives me a chance to walk away and come back and re-check everything.

Even with the 49.9 ohm resistors not on the c4S boards the resistance checks look ok.

Its a great looking layout when you see it all together!

4 coats of the Formbys Tung Oil looks really nice to me, just the right amount of gloss and very smooth to the touch...This was a lot easier than using the dark stain minwax on the Crack IMO.

Stay tuned, music on Tuesday!

Alex


Note: I did remove the springs and ball bearing on the coarse and fine volume pots...way too much force for me, with one side removed on each the adjustments become very smooth IMO.

[adydula]

MUSIC!!!

Smile!

Got the resistors today popped them in, voltages checked out ok.

Driving the Mainline with a Schitt Bimby MB dac...sounds great, all switches seem to work ok.

Its a great feeling when things wokr first time!!

Be back with a detailed "review"....

Alex

:>)

[adydula]

Paul, Doc...

On the front of my Mainline Power Xfmr there are some noticeable Lines or more of droolings of waht looks like the sticky stuff that coats the transformer
laminations...its in the front side and quite visable.

Is there anything I can carefully apply to take this sticky stuff off??

I tried some alcohol on a q-tip but it doesnt touch it...

Maybe some acetone?? Carefully used?

Alex

[Paul Birkeland]

You don't want to take the sticky stuff off, it's integral to proper operation of the transformer.

You can very lightly sand the high spots down a bit, but I'd recommend putting more  varnish over the lamination stack when you're done.

[adydula]

Ok Understand....will do this and re-coat with some varnish...

Thanks
Alex

[adydula]

Paul,

I see in a tube manual for the 6C45pi the plate voltage is spec's as 150 volts.

145 v is pretty close to this, but was wondering why the 5 v delta?

Alex