5E3 build log! Criticism and suggestions welcome!!

[Champ_49]

Hey everyone.

Just thought I'd start my 5E3 build log.  This would be a good thing to document for myself as well as allow others to see my build. 
I just got the parts in today from Hoffman.  Everything except for the trannys and some board components are from Hoffman.  Let's see how this build goes.

Today I got the chassis, and transformers.  Arrived and nicely packed!

I've gotten quite a bit done today. 

First the preliminary power tube socket (1.5K) resistors to pins 5&6.

Next, I just did the heater wiring.  Took me about 4 hours straight just to do this. 
I am assuming that the green on green doesn't have to be colour coded? 

Anyways, here are the pics.

Forgot to mention I am doing this according to the triode electronics layout since the transformers are based on the lower voltage windings that they have on their site.

Thanks for looking! And let me know if there is anything that looks wrong!!

[Willabe]

1st, Welcome Jay!

Looks good!

I don't see a CT for the heaters?


            Brad     

[Champ_49]

Thanks for the welcome! 
Yup, you're right. I did the CT for the heaters last.  I had to do the artificial heater tap for this since the PT didn't have the CT for the heaters.

[Willabe]

I had to do the artificial heater tap for this since the PT didn't have the CT for the heaters.

Ok, you should be good then, just checking.


          Brad   

[Champ_49]

I was looking up some different layouts for the 5E3 and found that some of these have a speaker out jack 12A with ground switch vs an 11A jack without ground switch.  I think I read somewhere that the 12A jacks are used for speaker jacks for a safety measure in case no load is connected while the amp is on?  Can someone clarify what the difference is using it one way vs another?  Does it really make a difference?  In one layout I see that one speaker jack is used as an 8 ohm tap while the other is hooked up to a 4 ohm tap.  I plan to do it this way.  I am a bit confused. 

Here are a couple of layouts I found. 
Layout 1 uses an 11A jack without a ground switch
http://site.triodestore.com/5E3_Layout_Diagram.bmp

Layout 2 uses a 12A jack with a ground switch.
http://site.triodestore.com/5E3DeluxeLayout40-18017120V.pdf

Not sure which one I should be using.  Or if it doesn't matter I'll stick with the layout 1 since I only have two speaker out jacks that are 11A.

Can someone please clarify?
Thanks

[Champ_49]

Thanks Brad for checking!

It's great to have another set of eyes.  As it is one of the reasons I am here.

This is day 2 of the build.  I haven't done much but thought I'd post a few pics of the wiring so far.

First is the artificial CT for the heaters I was talking about.  Not sure you can see the 100 ohm 2W resistors.  Kind of hiding there.

Next is the 5Y3GT rectifier tube socket wiring (Did I get the name right??)

Last is the overall progress so far. 

[sluckey]

In one layout I see that one speaker jack is used as an 8 ohm tap while the other is hooked up to a 4 ohm tap.  I plan to do it this way.

Then use the 11A jacks.

[Champ_49]

Yup. That's what I'm going to do. 

I just wanted to know why they would wire it one way vs the other way for speaker outs. Anybody know why they would use one way vs. another??  I am just curious.  Or was I right about the safety of when using the 12A.

[sluckey]

On the 12A jack you would connect the switch terminal to the ground terminal. This has no effect when a plug is inserted. But it will short the jack tip to ground when nothing is plugged in. A short circuit is better than an open circuit in tube amps. Your amp can be damaged if you play a guitar through the amp with an open speaker load.

Doing it your chosen way gives you two choices of speaker impedance, but you cannot use a shorting jack in this case. And you can only use one jack at a time.

[Champ_49]

Thanks Sluckey

So the saying goes. You can't have everything.

[sluckey]

Actually, in this case you can. But you will need an impedance selector switch such as Hoffman sells.

[Champ_49]

Yup.  That's what I was thinking of doing.  But I am planning on making a combo amp. so I probably won't be swapping speakers too often.  I'll just stick with the two impedance speaker outs.

[Champ_49]

Ok.  Have been too busy to post pics but this is Day 3 of the build.
So I'll have to lump two posts on one day.

Basically the inputs jack wiring and OT wiring.

First is the input jack and potentiometer wiring harness.  Still not connected to the board. But here is it.

Second is a shot of it inside the chassis.  The grounding wires (green) are super thick so it was a squeeze to try and get all those wires into some of the grounded lugs of the input jacks as I like to actually crimp or make mechanical connections to everything.


Third is the wiring of the OT wires (blue and red) to the power sockets. Tried to make all the leads tight up against the lugs with no exposed leads. 

[Champ_49]

Day 4 log.

The last part took me awhile to build, especially the input jack and potentiometer wiring.  Basically because of all the wires that needed to be stuffed inside some of the lugs,.. very tight.

Now the fun part.  The component board.  I got a lot done today, as I pretty much wired the whole component board.  I was expecting to take about 2 days (half day 1 and half day 2, or the whole board if I was up to it) for the component board build, but I just kept chugging away.  In total I'd say this took me about 4 hours total.  I took things are slow as possible, doubling checking and rechecking every connection.  Also, making sure I was soldering the points properly.

For soldering I heated my iron up pretty high.  hold it up against the junction of the component and wires.. place the tip of the solder against the joint (and not the iron), as soon as it melts and flows through the joint I take it off. The solder melting will tell me it's hard enough to make a properly chemically bonded connection.  No melting of the solder on the joint means the joints are not heated up enough so I can hold it longer before overheating any component.

I realized that for builds you really have to know when to stop.  At least for me.  It's easy to just keep going and realize the time. 
This time I set a goal, so I'll say to myself "if I get half the component board done I'll be good, the whole component board if I'm lucky". 

Once the component board was 90% done I said, ok that's it.  Time to stop.  This way you won't be chugging away even more and then there are more chances of making mistakes etc.  You need to rest.  So off to bed..


First pic is the 90% complete component board (back side wiring).  I tried to keep these wires as direct as possible.  Also I didn't want the wires to go along the eyelets blocking them.  So for these I had to make a bit of a loop. 

Second pic.  Top side of the board. 

So far so good.   It looks silly but I cut the wire lengths pretty long.  Just in case because it's better to have a longer length of wire than one that is too short. 

[Champ_49]

Day 5!

I started working on this a bit earlier today in the morning before I start work. This is part 1 of day 5.

First thing was I tried to fit the board into the chassis and line up the holes I drilled to mount the board.  It was a tight fit but I managed.  I decided I wanted to use #10 screw and nut just, instead of #8.  I saw in a few other builds they seemed to be using a larger thicker screw.  And plus anyways, Hoffman supplied me with a thicker screw pair so I drilled the holes a bit bigger to fit these.  Through the boards and the chassis.  Lined up well.

So last thing is I double checked the back of the board to make sure these back board wires were going to the right place.  I did Hoffman's suggestion, this is common sense but it's good he pointed it out.  After checking, highlight what you just checked.  This common sense tip helped out great.
Of course when actually soldering the components and wires I double checked all connections but it's always good to triple check.  I hope I didn't miss anything!!
As this could still happen!

I started wiring the first wire coming off the 820 ohm/25uF pair.  I ordered these cloth wires from Hoffman.  As the other ones I've seen all have a pvc coating on it and I preferred to use wire where you can actually push back the cloth.

Reality set in quick after this first wire.  These are 22 awg so thin to begin with and solid core so it can only take a limited amount of bending back and forth before it fatigues and breaks. 

Anyways, luckily this happened on the very first wires.  If this happened on any other wire after I soldered some previous wires to the sockets already it would've been very difficult to fix this.  Plus I remember for the first wire I had crimped it with a plier so it could have damaged a part of the wire by crimping too hard. 

Trying to bend this first wire back and forth to get it in shape caused it to break off at the weakest link (at the junction).  I had to unscrew the board, desolder the existing solder with a desoldering braid,  take the little piece of crimped wire lead inside the eyelet out and replace it with a new wire.  This mistake could be time consuming.  Luckily I hadn't made other wires connections off the board as this would have been a pain.  Now I have to be extra careful with the rest of the wires to be soldered to the sockets and switches.


Things happen but it's best to try it avoid it in the first place.   I think this is the emoticon I'd use for most of my builds.


I did the rest of the wiring to the power tube sockets. 


So progress so far..

First pic:  some of the wiring on the first tube socket.  The cloth is very useful to avoid exposed leads, but sometimes it can get in the way when trying to bend the lead into the lugs or connection point. At least for me this can turn out to be a real mess.
For this I use an alligator clip to hold it back while I bend and solder it into the lugs.  Before this I push out the excess cloth and snip off the excess.  Then I push it back and use the alligator clip.  Next I pull the cloth back over the exposed lead. Will post a pic of this later on at night today.

Second pic:  The wiring of the power tubes.  (It looks a bit messy but it will do)

Last pic, the progress so far.

[Willabe]

Looking real good.

I don't know if your doing this but put an old or cheap tube in the socket as you solder them to make sure the socket pins are lined up correctly. 

          Brad     

[Champ_49]

Thanks Brad!
 

[Champ_49]

Thanks everyone for checking out the build!

Btw, I wanted to say any criticism, suggestions or constructive feedback is welcome!
I know I'm not really that great with lead dress and neatness so if you see anything let me know!!!


 

[Willabe]

Go back and read reply #15, I added something.


             Brad   

[Champ_49]

Thanks again Brad!

Putting a tube in while soldering was something I never knew!  Thanks for the advice!  I will definitely try that for the next 12ax7 tube socket tonight.
The whole time I would just solder it without the tube.

[Champ_49]

Finally got the build finished.

But I'm sad to say that there was quite a bit of hum. I used triode electronics layout. I have attached the link below!!
I read some info on the forums here about this but I was still confused.

I did some "mods" by using something I found on another forum by Bruce from Mission amps.

- Basically moved the red/yellow CT and soldered directly to the negative lead of the first filter cap.  which is then run to a lug that is bolted down near the PT.
- Connected the 820 ohm/25uf directly to one of the ground lugs of the inputs.
- Moved and soldered the artificial 100 ohm CT directly to the positive end of the 250 ohm cathode biasing resistor/25uf pair.
- connected first filter cap ground to the second,
- disconnected the ground between the third filter cap to the second
- connected the ground of the third filter cap to the ground lug of one of the volume pots , this connects to the second preamp grounds mentioned above.

Does this seem right? Or did I miss something here.

I still get quite a bit (significant) of hum with the guitar plugged in.
Not plugged in there is white noise when turned up and a very faint low freq hum.

Now with the guitar not plugged in the hum has reduced significantly, just a lot of white noise with the volume turned up.  But there is still a faint hum,.
Now when I plug the guitar in the hum comes back with a vengeance.  And increases with the volume going up.
Is this normal?

I have heard that these 5E3 amps are dead quiet.  But have heard a lot of people having issues with the hum from other forums.

[eleventeen]

"- Moved and soldered the artificial 100 ohm CT directly to the positive end of the 250 ohm cathode biasing resistor/25uf pair."


???


I wouldn't do that. It should go either to ground, chassis ground, power supply ground, or, if you have a scheme where you are raising the filaments with a DC offset, to a steady-state source of DC.


"- Connected the 820 ohm/25uf directly to one of the ground lugs of the inputs.
- Moved and soldered the artificial 100 ohm CT directly to the positive end of the 250 ohm cathode biasing resistor/25uf pair.
- connected first filter cap ground to the second,
- disconnected the ground between the third filter cap to the second
- connected the ground of the third filter cap to the ground lug of one of the volume pots , this connects to the second preamp grounds mentioned above."


I wouldn't do *any* of those things. I sure would not do any of those things if I had a hum problem and was looking to kill it.


The overall concept is: You have a power supply ground and a signal ground. Within themselves, they need and want to be robust, high current connections. But they should connect together only at one spot.

[Champ_49]

Thanks for the reply.

The funny thing is after I did these I couldbe sworn that the hum issue was resolved with nothing plugged in.

This is the exact quote from Mission.
maybe I misunderstood it? Another guy did this and he said his hum problem was solved.
If you don't have a brass plate behind the pots and jacks.... use raw zinc plated lock washers under all of them.

"Pull the grounding lug of the two volume pots right down and solder them to the pot's shell.
The first two filter caps (or all three) negative leads can be connected. 
Main thing is to bring the red/yellow center tap from your high voltage secondary right to the eyelet of the negative lead on the first filter cap... you can then run a ground wire from there to the chassis.. like a PT mounting bolt with a star washer lug.
The preamp stages should be ground well away from that point... ground the 12AY7's 820 ohm resistor and it's bypass cap, of the 1st preamp tube to any of the grounded lugs of the input jacks.
Ground the 12AX7, second preamp stage's 1500 ohm resistor and it's bypass cap with the grounded 56K resistor, close to the tone pot ground or at the negative lead of the third filter cap.... and don't forget to ground the 220K power tube grid load resistors to the negative lead of the third and final filter cap's negative lead too.
If you have a 6.3vac filament transformer with a center tap... bring that wire...(usually green with yellow stripe) ...
over to the positive end of the power tube's cathode biasing resistor or right at the first 6V6 tube socket lug 8.

If you don't have a center tap, use two 100ohm to 150ohm 1/2w resistors across the two 6.3vac leads, to make a virtual center tap, and connect the junction of those two resistors at the cathodes of the power tubes.
Should be pretty quiet"

[Willabe]

If you don't have a center tap, use two 100ohm to 150ohm 1/2w resistors across the two 6.3vac leads, to make a virtual center tap, and connect the junction of those two resistors at the cathodes of the power tubes.
Should be pretty quiet"

That works and is an old trick. I've never read anything bad about lifting the heaters like that.

But you still have to have the grounding correct.


              Brad     

[Champ_49]

Thanks for the input Brad.

Can I in fact connect the floating end of the 100 ohm resistors directly to pin 8 of the power tubes?  From my understanding I was assuming I can connect those two to the positive end of the 250 ohm/ 25uf  pair. Is this essentially the same thing?  I am taking all this in a literal sense as I am still quite new to this.   Please bear with me.!

[Willabe]

Can I in fact connect the floating end of the 100 ohm resistors directly to pin 8 of the power tubes?  From my understanding I was assuming I can connect those two to the positive end of the 250 ohm/ 25uf  pair. Is this essentially the same thing?

Yes and yes.


                Brad     

[Champ_49]

Thanks again for your help Brad.

I moved that back to the PT bolt again thinking that wasn't the right way based on what eleventeen said.
I will move it back to the 250 ohm to see how that will affect the hum.

So i have tried my best to incorporate a grounding scheme based on the power and signal idea.  Where the signal ground and power ground are separated.

This took me some time to do and I am not sure if I am on the right track but here are some pics.

1st pic:
This is what i did according to what I read from a quote from Bruce.  I moved the red and yellow CT wire and soldered it directly to the negative of the first power filter cap.  This is jumped to the 25uf/250ohm pair, which is then soldered to the lug at the PT.


2nd pic:
shows the next two filter caps.  the layout had the 2nd power filter and the 3rd signal filter jumped, so I cut the jumped wire from the 2nd and 3rd filter cap and instead jumped the 1st and 2nd power filter caps.  This makes sense because these are the two power filter caps?  So essentially I separated the signal cap from the 2nd power filter cap.  Did i do this correctly??
Also,  I soldered the two ground wires coming off of the ground lug of the pots and soldered it directly to the negative ground of the 3rd cap (signal filter cap).. Is this ok??

3rd pic:
This is a shot of the 2 X 100 ohm resistors soldered to the 6.3V line and the other end bolted to the PT lug along with the ground wire from the wire from the first cap  and the ground wire from the speaker out.

4th pic:
I also wired a bare buss wire from the 25uf and 820ohm pair at the preamp section to the nearest ground lug of one of the input jacks. 

~~~~***** I didn't do a straight buss along the board like some I've seen.  These grounding wires are on the back of the board.


I plugged it in and still have that faint low level hum when unplugged and really loud hum when the guitar is plugged in.  which increases as the volume is turned up.
I am so tired now I think I will have to call it a night..

All in all I tried my best to separate the power grounding from the signal grounding.  So the Signal ground (preamp section) has a common point at the input jack.  The power section is all tied to the PT lug along with the ground for the speaker jack..

BTW is it ok to ground the speaker out at the same point??

Sorry for the long story. 

[Willabe]

Here's an old Ampeg with the heater CT humdinger pot wired to the power tubes cathode.

http://el34world.com/charts/Schematics/files/ampeg/ampeg_625d.pdf



                Brad     

[Champ_49]

Thanks Brad for the link!

Unfortunately I am very bad at reading schematics.  I wish I could read it like a pro but I can't.
I have to learn I guess if I want to continue this amp making hobby 

I did attach the 100 ohm resistors to the 250 ohm positive side. 
I don't know if you can see it in this pic.  Thanks for the advice!

[Champ_49]

I should have called this post 5E3 woes!

I was tightening one of the four bolts of the power transformer where the ground lugs are connected to and the mounting bolt snapped.
I am now considering moving the ground wires to the bolt on the other side.

My question is, is this broken bolt of concern?  I don't think it damaged the transformer itself but I'm now worried it might not be structurally unstable.  Maybe I will have to find a small L bolt to flush it in place.

But is this is potential for rattling noises and such? Already I noticed that with the chassis sitting on top of my speaker cabinet there is some rattle.  I tightened everything and in the process snapped this bolt right off.

Any suggestion??
Are three bolts sufficient to have it stable you think??


Or am I worrying too much?

[Toxophilite]

It has been my experience that rattles can be caused as much by items near the amp as by the amp itself
I personally would wait till the whole thing is assembled before you troubleshoot that and then isolate it on something with a rubber pad or similar.


As to your PT, I'm not a pro but i think if you're PT is held on firmly with 3 other bolts it should be okay. On some of these PTs you can actually replace the bolts(which I did once when replacing an PT on a an amp with a different similar spec one, it required spacers and longer bolts and I was able to swap them out for longer ones.


Just a couple of ideas and opinions.
I would wait for those who are more experienced to chime in though


p.s it has also been my experience that one builds an amplifier...and then one figures out why it doesn't work how it should 

[Champ_49]

Thanks for the reply!

I agree.  I have had that experience before with my other build!

I was looking at the power transformer and it does have bolts that go right through the transformer.
Something like this:

http://www.classictone.net/40-18021-05.JPG

I don't think I can actually unscrew the bolt with a screw driver and replace this?  I have a feeling it won't be removable.

[sluckey]

I don't think I can actually unscrew the bolt with a screw driver and replace this?  I have a feeling it won't be removable.

There should be another nut on the other side of the chassis. You need to remove all nuts from the inside of the chassis so you can lift the PT up enough to get a wrench on the remaining nut. Loosen this nut then the screw can be removed. Then just drop another nut in the PT being careful to use all the bushings, sleeves etc,. Then tighten the nut, drop the PT back into the chassis and reinstall the four nuts on the inside of the chassis. Use a nutdriver to tighten the nuts and don't break them. Better yet, let your wife do it! 

It should only take 5 to 10 minutes to replace that bolt.

[Champ_49]

Thanks Sluckey!

You're right. There is a nut on the other side or there should be from the pics.
this might be a silly question but if I remove the nut and screw of the transformer would this loosen the laminates?  The screws don't hold the laminates in place do they? ?

Sorry. I just wanted to make sure so I don't damage the PT.

[sluckey]

if I remove the nut and screw of the transformer would this loosen the laminates?  The screws don't hold the laminates in place do they? ?

The screws do hold the laminations together, but there is no danger of loosening the lams by removing one screw. You would have to remove all four screws and the end bells and then likely have to pry the lams apart.

PS... If you have trouble finding a screw long enough, just drop by a motor rewinding/repair shop. They should have plenty.

[Champ_49]

Thanks again Sluckey!

That makes sense.  Worst case scenario if it does get damaged then I'll just have to get a new d Haha.  doesn't hurt to try.  Just reading that now and yes they say that the laminates have to be pried open after taking out the bolts Since they are held together by a thin coat of shellac.

So one lesson learned today At least for me. Never over tightnen!!

[Champ_49]

Thanks for the extra tip! Was actually wondering that too. I think I saw a bunch of long screws at the local hardware store.
These are usually 8 size screws I'm assuming? Forgot what size the nut was to hold it in place insude the chassis.  But I think it was an 8

Back to the workbench for this haha.

[Toxophilite]

Remember at the hardware store if you want to avoid mockery/misdirection you are looking for a 'bolt' , not a 'screw'

[Champ_49]

Remember at the hardware store if you want to avoid mockery/misdirection you are looking for a 'bolt' , not a 'screw'

Hahah. I didn't write that. 
But yes a bolt is the correct word.

[Champ_49]

Ok. Just letting you all know the bolt will not come out.
I got the nut loose and the bolt is just going around and around without actually coming up.
It's stuck there for good.

I don't think I can have this PT with one of the mounting bolts broken.


I might have to just order another one.

Maybe I'll have thus one as a spare for other projects.

[eleventeen]

Undoubtedly, the threads and shank deformed a tad where the bolt sheared and it's (they are) being held in by the laminations. Get either a box-type nail (longer, thinner than 16d framing nail) or a long finish nail or a length of coat hangar wire or welding rod and you should be able to push the broken bolt out from the (formerly) threaded end. It's just a long bolt through a hole.

You can probably get away with only three tranny bolts, unless of course the breakage of that bolt killed your grounding scheme. There should be a way to get a long bolt like that without going insane. Is there a surplus joint around you where you buy an old tranny? You could even use continuously threaded rod, though the steel used in "allthread" is pretty crappy and you'll have the same problem if you overtighten.

[Champ_49]

Thanks. I got it out.

It is just a long bolt. It's not threaded through the hole but it has a thin layer of some shellac around it. So it doesnt actuallt screw in As i thought. I guess to keep it tight around.

I used a long screw against the tip and  a hammer to Push it through and out.

I'll see if the hardware store has the long bolt tommorrow.

[Willabe]

So it doesnt actuallt screw in As i thought.

Yes, doesn't need to. The bolts just hold it together.

It's not threaded through the hole but it has a thin layer of some shellac around it.

I used a long screw against the tip and  a hammer to Push it through and out.

Yep.


                Brad     

[Champ_49]

Thanks so much for all the help! I really appreciate it!

I finally found the bolts and even some shellac. Just to keep it as close as possible to how it was.  Would you recommend pouring some shellac through the bolt and hole?  Because the actual hole is larger than the bolt it must've been put in to keep it sturdy.

[sluckey]

Don't use any shellac. Just use the same nuts and washers that were on the original bolt. Your replacement bolt is the same size as the original, right?

[Champ_49]

Yes. It is the exact same size. Is there a reason why not to??
I mean would this damage anything? ?

[sluckey]

It's more a case of there is no reason to do it. It probably isn't shellac anyhow. More likely varnish. Varnish got on the bolts when the transformer was dipped to coat the lams. Varnish was not purposefully put on the bolts.

I think you're really way overthinking this very simple task.

[eleventeen]

"I think you're really way overthinking this very simple task."


+1

[DCbluez]

Thanks again for your help Brad.

I moved that back to the PT bolt again thinking that wasn't the right way based on what eleventeen said.
I will move it back to the 250 ohm to see how that will affect the hum.

So i have tried my best to incorporate a grounding scheme based on the power and signal idea.  Where the signal ground and power ground are separated.

This took me some time to do and I am not sure if I am on the right track but here are some pics.

1st pic:
This is what i did according to what I read from a quote from Bruce.  I moved the red and yellow CT wire and soldered it directly to the negative of the first power filter cap.  This is jumped to the 25uf/250ohm pair, which is then soldered to the lug at the PT.


2nd pic:
shows the next two filter caps.  the layout had the 2nd power filter and the 3rd signal filter jumped, so I cut the jumped wire from the 2nd and 3rd filter cap and instead jumped the 1st and 2nd power filter caps.  This makes sense because these are the two power filter caps?  So essentially I separated the signal cap from the 2nd power filter cap.  Did i do this correctly??
Also,  I soldered the two ground wires coming off of the ground lug of the pots and soldered it directly to the negative ground of the 3rd cap (signal filter cap).. Is this ok??

3rd pic:
This is a shot of the 2 X 100 ohm resistors soldered to the 6.3V line and the other end bolted to the PT lug along with the ground wire from the wire from the first cap  and the ground wire from the speaker out.

4th pic:
I also wired a bare buss wire from the 25uf and 820ohm pair at the preamp section to the nearest ground lug of one of the input jacks. 

~~~~***** I didn't do a straight buss along the board like some I've seen.  These grounding wires are on the back of the board.


I plugged it in and still have that faint low level hum when unplugged and really loud hum when the guitar is plugged in.  which increases as the volume is turned up.
I am so tired now I think I will have to call it a night..

All in all I tried my best to separate the power grounding from the signal grounding.  So the Signal ground (preamp section) has a common point at the input jack.  The power section is all tied to the PT lug along with the ground for the speaker jack..

BTW is it ok to ground the speaker out at the same point??

Sorry for the long story.

[DCbluez]

Hey,

It is perfectly OK to ground the speaker ground to the chassis star ground bolt.

If you look at Doug Hoffmans layout and follow this method it works perfectly. I have built 3 Tweed Deluxe amps and all came out perfect. I did add another 1 meg pot to my Tweeds so I can adjust both sides of the V1, hi/lo and mix them with a pair of 220K resistors. In other words the 3 pot Tweed Deluxe volume tone works out kind of strange to me. Sounds good but limited. 2 volume and 2 tone pots works very well for these amps.

Most of the time hum is caused by the heater wires and the V1 tube picking up the 60hz AC hum and amplifying the signal. You could have the wires twisted out of phase from V1 to V2. Unplug it and check with a meter and make sure all of the heater wires are in phase. Pin 9 V1 must also be pin 9 V2 etc. Pin 4-5 must be pin 4-5 both V1 and V2. If one gets out of phase it can induce hum.

Center tap on the heater wire coming from the tranny must be on star ground. Very tightly also and get good contact to the chassis for all grounds. Also the heater wires have to be twisted carefully and very tightly so the hum is cancelled out.  Its all in a careful wiring layout and make sure you have space between all the wires coming from the board to the tubes or anywhere in the wiring scheme. I use a stiff wire so it is bent to stay in place away from other wires etc.

I do not really like the soldering wires to the pots method. I make up a solid wire ground buss and solder grounds to the buss wire and suspend it rigidly and attach the grounds starting at the inputs and work right to left in a flow. Even though I used the 12A Switchcraft jacks which do ground to the chassis at the input this is totally quiet and the ground loop has no effect as far as noise.

I have also built up 5 Marshall 2204 builds successfully which are much more finicky that the Tweed Deluxe builds. These are very hum sensitive.

I also have found after building near 20 amps that Mallory Caps have better tone than the Orange Drops. I have used Mallory, Sprague, Sozo, and about to try out the Mojo Dijons.

Anyway you need to solve the hum problem and I have been there and try out checking the heater wires and their twist and location and distance from other wires and phasing and see if that solves you hum issue. You could also have a bad preamp tube, haha.This happens a lot.

Good luck