New Posts New Posts RSS Feed - 1970s Design Indulgence
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Welcome to the Graham Slee Audio Products Owners Forum

 

Open to all owners plus those contemplating the purchase of a Graham Slee HiFi System Components audio product and wishing to use this forum's loaner program: join here (Rules on posting can be found here)

This website along with trade marks Graham Slee and HiFi System Components are owned by Cadman Enterprises Ltd


1970s Design Indulgence

 Post Reply Post Reply Page  <1 297298299300301 345>
Author
Graham Slee View Drop Down
Admin Group
Admin Group
Avatar
Retired

Joined: 11 Jan 2008
Location: South Yorkshire
Status: Offline
Points: 16298
Post Options Post Options   Thanks (1) Thanks(1)   Quote Graham Slee Quote  Post ReplyReply Direct Link To This Post Posted: 26 May 2023 at 4:15pm
All's quiet on the 7eventy's front because we're awaiting a special tool. It's for deburring the rear of the step-drilled holes. Things like loudspeaker binding posts and fuse holders require a 13mm diameter hole, and the W Neal Services WP82 (Roper Whitney style) hand punch only goes up to 11mm (7/16"). Otherwise, the WNS WP82 is a fantastic piece of kit that punches beautiful burr free holes in the 1050 grade 1.2mm thick aluminium.

The type of deburring tool leapt back from the canyons of my mind, and I can remember using one many years ago. I'm hoping
will be as good as the one I remember.

Early next week I should be able to show you pictures of the "dry fit" case equipped with the populated panel, IEC inlet and on/off switch.
That none should be able to buy or sell without a smartphone and the knowledge in how to use apps
Back to Top
Graham Slee View Drop Down
Admin Group
Admin Group
Avatar
Retired

Joined: 11 Jan 2008
Location: South Yorkshire
Status: Offline
Points: 16298
Post Options Post Options   Thanks (0) Thanks(0)   Quote Graham Slee Quote  Post ReplyReply Direct Link To This Post Posted: 27 May 2023 at 7:18pm
There's noticeable runout on the drill press chuck which is also responsible for poor quality holes. The Nova Viking drill press was flipping expensive and you'd expect some precision. However, if I remember correctly, the chuck side of the arbor had a gouge in it, probably caused by the bad packaging, and I did try to polish it out, but it could be what's responsible for the runout (more than likely).

Oh what fun and joy... dial gauge and mag stand on the way. Only one winner here and that's Amazon!
That none should be able to buy or sell without a smartphone and the knowledge in how to use apps
Back to Top
Graham Slee View Drop Down
Admin Group
Admin Group
Avatar
Retired

Joined: 11 Jan 2008
Location: South Yorkshire
Status: Offline
Points: 16298
Post Options Post Options   Thanks (1) Thanks(1)   Quote Graham Slee Quote  Post ReplyReply Direct Link To This Post Posted: 28 May 2023 at 2:10pm
Sheet metal meets MDF...

I call it "taking back control" or perhaps self sufficiency.

We can manufacture, and have more control over it than having to depend on others, who'll only let you down.

sheet metal meets MDF


look! no screws

(look, no screws! The rear panel mock up is held in place thanks to a passing two by four)

OK, I'm retired. I don't have a business to promote it. And a lot of people have forsaken it. But I'm seeing this amplifier (and its preamp) through to the finish!

That none should be able to buy or sell without a smartphone and the knowledge in how to use apps
Back to Top
Mikeh View Drop Down
Senior Member
Senior Member
Avatar

Joined: 04 Dec 2018
Location: Yorkshire
Status: Offline
Points: 541
Post Options Post Options   Thanks (0) Thanks(0)   Quote Mikeh Quote  Post ReplyReply Direct Link To This Post Posted: 28 May 2023 at 2:16pm
"But I'm seeing this amplifier (and its preamp) through to the finish!

Good to hear after all this time & effort!
Mike

Technics sl1210g with Victor U-2
Accession MM, Majestic + Proprius, Solo ULDE
Cambridge Audio CXC CD player
Lindemann Limetree Bridge streamer
Harbeth P3ESR XD paired with 2x REL t5x
Back to Top
Graham Slee View Drop Down
Admin Group
Admin Group
Avatar
Retired

Joined: 11 Jan 2008
Location: South Yorkshire
Status: Offline
Points: 16298
Post Options Post Options   Thanks (0) Thanks(0)   Quote Graham Slee Quote  Post ReplyReply Direct Link To This Post Posted: 28 May 2023 at 2:31pm
Notes on the above

IEC mains inlet: both fixing screws are screw and nut, and will each have a solder tag on the inside wired to mains earth and the power supply chassis, such that touchable metal parts (the screw heads) are earthed, meeting with class-1 safety regulations. The wood panel rear will be routed to thin the material such that a protective boot can be attached to the IEC inlet's rear.

Speaker binding posts: these are purposely mounted in from the recessed edge such that a 4mm plug can be inserted horizontally where required for bi-wiring.

The HT fuses (one per channel) are rear panel mounted to save having to take the lid off the amplifier. The fuse holders are not classed as mains safe, but don't have to be because the HT voltage is not mains! And that means it's easier to change a fuse if required.


Edited by Graham Slee - 28 May 2023 at 2:33pm
That none should be able to buy or sell without a smartphone and the knowledge in how to use apps
Back to Top
Sylvain View Drop Down
Senior Member
Senior Member


Joined: 18 Jan 2010
Status: Offline
Points: 481
Post Options Post Options   Thanks (0) Thanks(0)   Quote Sylvain Quote  Post ReplyReply Direct Link To This Post Posted: 28 May 2023 at 2:35pm
It looks very well fitted, the rear aluminium panel with sockets seems very precisely customised to it's enclosure. The effort is commendable .
Back to Top
gwebster View Drop Down
Senior Member
Senior Member


Joined: 04 Oct 2014
Location: Liss, UK
Status: Offline
Points: 175
Post Options Post Options   Thanks (0) Thanks(0)   Quote gwebster Quote  Post ReplyReply Direct Link To This Post Posted: 28 May 2023 at 2:45pm
Originally posted by Graham Slee Graham Slee wrote:

OK, I'm retired. I don't have a business to promote it. And a lot of people have forsaken it. But I'm seeing this amplifier (and its preamp) through to the finish!
Keep on! Keep on! 
Whilst I didn't design hi-fi for my living, my first project on retiring was building a preamp and power amp. These were published designs with kits available (for the electronics). As far as the metalwork was concerned, my cases came from Italy and the supplied panels were then waterjet cut for me by a local firm near where I was then living (Falmouth) to accommodate the rotary controls, IEC power connector and other connectors.

Six years on and I'm doing more and more of the stuff, including circuit design, PCB layout and embedded controller programming.

Currently, any PCBs I design are then produced in China. I do wish I could find sources in the UK that can compete with them on price and delivery. At least my cases still originate in Europe.


Inspire Apollo tt, O/L modded RB250, Ortofon 2M Black, Slee Different Approach inspired Phono, Putzeys Pre, Cusat, Raspberry Pi/Volumio, Bitzie, Self Load Invariant Power, Acoustic Energy AE509s
Back to Top
 Post Reply Post Reply Page  <1 297298299300301 345>
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.01
Copyright ©2001-2018 Web Wiz Ltd.

This page was generated in 0.188 seconds.