SpeakerTalk Forum Index SpeakerTalk
This forum has been set up to facilitate discussion of 1970s KEF speakers and drive units. The owner of the Forum has no connection with KEF Audio.
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

105.1 tweeter mounting hardware

 
Post new topic   Reply to topic    SpeakerTalk Forum Index -> KEF Speakers from the 1970s
View previous topic :: View next topic  
Author Message
writethis
Introductory Contributor


Joined: 04 Sep 2014
Posts: 7
Location: Nashville USA

PostPosted: Thu Apr 27, 2017 5:56 pm    Post subject: 105.1 tweeter mounting hardware Reply with quote

Hi, after several years involved in a torrid love affair with 103.2, I have talked a beautiful pair of 105s into coming home with me. Previous owner had replaced the original tweeters with something else. I've managed to source a pair, and even have the original mounting bolts. But several of the T-nuts from inside the tweeter cabinets have gone missing. I can't find either metric or imperial versions that fit the original bolts. Any chance someone can shed light? I could get all new bolts and T nuts, and paint the bolt heads black, but would much rather keep everything as original as possible. Thanks in advance.
Back to top
View user's profile Send private message
speakerguru
VIP Contributor 750+


Joined: 18 Nov 2005
Posts: 951
Location: Green Hut, Tovil

PostPosted: Fri Apr 28, 2017 8:01 am    Post subject: Reply with quote

KEF Electronics had gone completely metric by the time the 105|1 was produced. Most common screw size was M5, with M4 for smaller items like tweeters.

Otoh, weren't the mk1 heads made of MDF? In which case the units would have been held in by some sort if woodscrew.
Back to top
View user's profile Send private message
audiolabtower
VIP Contributor 500+


Joined: 06 Jan 2009
Posts: 544

PostPosted: Fri Apr 28, 2017 11:24 am    Post subject: Reply with quote

From memory the edges were rougher than MDF which is usually quite smooth and solid? Maybe they were still flooring grade chipboard so used the grip nuts? Or an early rougher type of MDF? The B300 baffle however has layers so looks like BBC style plywood.
Back to top
View user's profile Send private message
speakerguru
VIP Contributor 750+


Joined: 18 Nov 2005
Posts: 951
Location: Green Hut, Tovil

PostPosted: Fri Apr 28, 2017 12:10 pm    Post subject: Reply with quote

Early MDF most probably but could be that chipboard with the finer particles on the outside faces. In any event at time of writing, you can buy M4 T nuts here:
http://www.ebay.co.uk/itm/M4-M5-M6-M8-M10-Captive-T-Nuts-Pronged-Tee-Nuts-Blind-Nuts-Steel-Zinc-Plated-/222084492419?var=&hash=item33b5446c83:m:mwCG0rBkG8KFLCnq4Y3c49A
Back to top
View user's profile Send private message
writethis
Introductory Contributor


Joined: 04 Sep 2014
Posts: 7
Location: Nashville USA

PostPosted: Fri Apr 28, 2017 12:17 pm    Post subject: Reply with quote

EDIT: the heads are made of particle board, not MDF.

Thanks so much gents. I confess I don't know the difference between flooring-grade chipboard and MDF. The heads are indeed made from some sort of wood composite. The fasteners in question are called T nuts here in the colonies, grip nuts sounds like probably the same thing -- they're pressed into the wood from behind, and have little blades or teeth that penetrate the wood to keep the nuts from turning.

I ordered a little bag of what were supposed to be M4 T nuts from a seller on Amazon, and they're too big for the bolts. The bag itself is unmarked, so it's possible a mistake was made. One of the heads still has the original fasteners in place, so I know they (and the original bolts) are correct.

Even knowing that I'm on the right track with metric is a help. I'll update here when the puzzle is solved...


Last edited by writethis on Fri Apr 28, 2017 1:59 pm; edited 1 time in total
Back to top
View user's profile Send private message
writethis
Introductory Contributor


Joined: 04 Sep 2014
Posts: 7
Location: Nashville USA

PostPosted: Fri Apr 28, 2017 12:19 pm    Post subject: Reply with quote

speakerguru wrote:
Early MDF most probably but could be that chipboard with the finer particles on the outside faces. In any event at time of writing, you can buy M4 T nuts here:
http://www.ebay.co.uk/itm/M4-M5-M6-M8-M10-Captive-T-Nuts-Pronged-Tee-Nuts-Blind-Nuts-Steel-Zinc-Plated-/222084492419?var=&hash=item33b5446c83:m:mwCG0rBkG8KFLCnq4Y3c49A


Thanks speakerguru, this is helpful. Exactly the part in question.
Back to top
View user's profile Send private message
writethis
Introductory Contributor


Joined: 04 Sep 2014
Posts: 7
Location: Nashville USA

PostPosted: Wed May 03, 2017 2:41 pm    Post subject: Reply with quote

Update: so the hardware in question is indeed metric, but the size is M3.5. I ended up replacing the bolts on one head with the closest Imperial equivalent.

Speakers are back together and settling in/waking up. First impressions compared to my reference point of 103.2: these definitely take transparency to a new and higher level. They also exhibit a degree of scale and dynamic range which exceeds the smaller 103.2. Overall balance is tilted up just a bit - they're not overly bright, but low end and low mids could be more pronounced. I think they may benefit from being moved closer to the back wall, but this will require a) adding casters and b) rearranging furniture (including LPs).

Two other factors that may improve low end once addressed are replacing the hardened 38-year-old bitumen in the lower boxes, and measuring all the original caps to see how far they've drifted from spec. But for now I just want to just enjoy them and let them breathe for a while.

All in all, the 105s are a wonderful addition to my little collection of KEF reference speakers.

Thanks again for the help.
Back to top
View user's profile Send private message
speakerguru
VIP Contributor 750+


Joined: 18 Nov 2005
Posts: 951
Location: Green Hut, Tovil

PostPosted: Thu May 04, 2017 2:38 pm    Post subject: Reply with quote

M3.5 screws are very common indeed. All UK mains electrical wall sockets and fittings use M3.5. No need to bodge with the nearest imperial thread Shocked
Back to top
View user's profile Send private message
writethis
Introductory Contributor


Joined: 04 Sep 2014
Posts: 7
Location: Nashville USA

PostPosted: Fri May 05, 2017 3:50 pm    Post subject: Reply with quote

Ah, thanks speakerguru. The issue was finding t nuts in the M3.5 size. Jus to be clear, I did use screws and t nuts of the same size, so it's not as if I tried to force dissimilar threads to get along harmoniously.

The speakers are sounding glorious.
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    SpeakerTalk Forum Index -> KEF Speakers from the 1970s All times are GMT + 1 Hour
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group