Jammed capstan sleeve - UK Vintage Radio Repair and Restoration Discussion Forum

TALKINGWITHPYE · 3rd Jun 2020, 10:34 am

Hello from Dave, I was reading some of the posts on here yesterday and was put in mind to listen to some of my reel to reel tapes on my Akai 4000GS tape deck. I discovered that the capstan sleeve was stuck on the capstan so I could not set the speed to 3.75. I saw that WD40 is not the best for lubricating, so can anyone give me advice as to how to release said capstan sleeve please?

Radio Wrangler · 3rd Jun 2020, 12:10 pm

Is it the screw-on cap that's stuck, or is it just the sleeve alone?

David

One recipe for penetrating lubricant is 50% automatic transmission fluid and 50% cellulose thinners (acetone, mostly)
Because of the thinners, keep it off of plastics and paintwork.

Duck oil is quite good, too.

David.

garry71 · 3rd Jun 2020, 2:08 pm

I take it you've tried spinning it clockwise, then giving it a quick twist anti-clockwise?

I got mine off while the machine was out of the chassis, so I could grip the rear of the flywheel and it came off quite easily then.

TALKINGWITHPYE · 3rd Jun 2020, 2:35 pm

Thanks for your replies, the screw head comes off easily but the sleeve won't budge. Ok on the oil suggestions, there is a bloke accross the street from me works on cars so he might have the automatic transmission fluid.

TonyDuell · 3rd Jun 2020, 2:40 pm

Sometimes careful heating (hot air gun, hair dryer) or cooling (freezer spray) will get it free.

DMcMahon · 3rd Jun 2020, 2:43 pm

Holding/stopping the flywheel from turning maybe the key.

saxmaniac · 3rd Jun 2020, 4:56 pm

Why the witches brew for making lubricating oil? There's 3 in one type light oils readily available.WD40 is not much good for anything other than dispersing water and temporary protection against surface rust

emeritus · 3rd Jun 2020, 5:03 pm

Plus-gas or, if you can't find some, petrol lighter fluid are extremely penetrating. Never had to do a capstan sleeve, but for badly rusted bolts and shafts, see-sawing the two parts to and fro will normally eventually pump fluid into the gap.

ben · 3rd Jun 2020, 5:09 pm

I'd be inclined to try the heating trick. Use the tip of a soldering iron.

Radio Wrangler · 3rd Jun 2020, 5:36 pm

3-in-1 is OK, but not a particularly strong penetrator it's a domestically benign light lubricant. Plus gas is good, but I haven't seen any on sale for years. Used to use a formulation from Morris's of Shrewsbury in the garage.

The witches brew? well it's quite effective stuff.

Do not use car engine type oils as general lubricants. I know, we all used to, but it now has a package of quite unpleasant additives to deal with combustion products and lead-based bearings.

So Automatic transmission oil (which is also used as hydraulic fluid in power steering), is generally available and free from the nasties. It seems to only have an anti-foaming agent. The thinners is also generally available, thins the ATF and gets it into awkward places quite successfully. It also evaporates cleanly and leaves good lubricant behind. Just mind out for plastics and paint.

David

vidjoman · 3rd Jun 2020, 7:03 pm

I have a feeling that this added sleeve is keyed and will not turn on the smaller shaft. It should lift straight up. Perhaps try a small screwdriver to lift it if there’s enough room between the sleeve and the deck.

DMcMahon · 3rd Jun 2020, 8:35 pm

Have not seen a keyed one before on the Akai 4000 range or similar Akai.

I assume the 4000GS in Post # 1 is a typo, i.e. most likely should read 4000DS.

Radio Wrangler · 3rd Jun 2020, 10:05 pm

4000GS is a facelifted version with their Glass and Xtal head. Track switch moved out of head box as well.

Tha Akai sleeves are not keyed an any way, but what most people don't notice is that the bottom end of the capstan had a conical flare as it steps up to a larger diameter. The sleeve has a slight conical rebate on its opening, so when it sits on the capstan cone-on-cone gives accurate centring The underside of the nut is flat and faces onto the flat face of the outer end of the sleeve. It takes decent precision to not have terrible flutter with a sleeve adaptor, and it's the 7.5IPS speed that bears the brunt.

David

garry71 · 3rd Jun 2020, 10:58 pm

Quote:

Originally Posted by vidjoman

I have a feeling that this added sleeve is keyed and will not turn on the smaller shaft. It should lift straight up. Perhaps try a small screwdriver to lift it if there’s enough room between the sleeve and the deck.

Quote:

Originally Posted by DMcMahon

Have not seen a keyed one before on the Akai 4000 range or similar Akai.

I assume the 4000GS in Post # 1 is a typo, i.e. most likely should read 4000DS.

The manual for the x150D says it has a keyed capstan shaft, but no mention of a screw head for it, so the 4000GS might just be the slip on type.

DMcMahon · 3rd Jun 2020, 11:11 pm

Interesting, I have not seen the keyed/notched type before on Akai.

garry71 · 4th Jun 2020, 12:25 am

Quote:

Originally Posted by DMcMahon

Interesting, I have not seen the keyed/notched type before on Akai.

I thought all Akais had a notched capstan until I got my 4000D

red16v · 4th Jun 2020, 9:01 am

Various ways of fitting the resized capstan to the original. This website has some useful info.

http://www.oaktreevintage.com/Akai_R...eplacement.htm

red16v · 4th Jun 2020, 9:05 am

Quote:

Originally Posted by DMcMahon

Interesting, I have not seen the keyed/notched type before on Akai.

David, looking back this is a kit I bought for the X201D I recently passed on to you. But, it did not fit and the hifi shop I bought it from was most embarrassed! Note that the pinchwheel is a smaller diameter than the OEM one - that is probably the one I found and gave you, the capstan is long gone - it was nearly 50 years ago!

https://www.ebay.co.uk/itm/Genuine-A...-/113961240009

Andrew2 · 4th Jun 2020, 9:14 am

I'd be very wary of using any levering method, you can so easily put a slight bend in the capstan and you'll never get rid of the wow/flutter.
I came across bent capstan quite often when people had got a tape jammed in their cassette decks and the tape had wound itself tightly around the capstan. Instead of bringing the machine in for proper attention, they would attempt to force the tape out and the poor capstan bore the brunt!

DMcMahon · 4th Jun 2020, 9:18 am

Quote:

Originally Posted by Radio Wrangler

4000GS is a facelifted version with their Glass and Xtal head. Track switch moved out of head box as well.

Tha Akai sleeves are not keyed an any way, but what most people don't notice is that the bottom end of the capstan had a conical flare as it steps up to a larger diameter. The sleeve has a slight conical rebate on its opening, so when it sits on the capstan cone-on-cone gives accurate centring The underside of the nut is flat and faces onto the flat face of the outer end of the sleeve. It takes decent precision to not have terrible flutter with a sleeve adaptor, and it's the 7.5IPS speed that bears the brunt.

David

Still have not heard of a 4000GS, what you are describing sounds like the GX-4000D

3rd Jun 2020, 10:34 am	#1
TALKINGWITHPYE Pentode Join Date: Oct 2018 Location: Carrickfergus, County Antrim, Northern Ireland, UK. Posts: 126	Jammed capstan sleeve Hello from Dave, I was reading some of the posts on here yesterday and was put in mind to listen to some of my reel to reel tapes on my Akai 4000GS tape deck. I discovered that the capstan sleeve was stuck on the capstan so I could not set the speed to 3.75. I saw that WD40 is not the best for lubricating, so can anyone give me advice as to how to release said capstan sleeve please?

3rd Jun 2020, 12:10 pm	#2
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,858	Re: Jammed capstan sleeve Is it the screw-on cap that's stuck, or is it just the sleeve alone? David One recipe for penetrating lubricant is 50% automatic transmission fluid and 50% cellulose thinners (acetone, mostly) Because of the thinners, keep it off of plastics and paintwork. Duck oil is quite good, too. David. __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

3rd Jun 2020, 2:08 pm	#3
garry71 Tetrode Join Date: Apr 2020 Location: Birmingham, West Midlands, UK. Posts: 88	Re: Jammed capstan sleeve I take it you've tried spinning it clockwise, then giving it a quick twist anti-clockwise? I got mine off while the machine was out of the chassis, so I could grip the rear of the flywheel and it came off quite easily then.

3rd Jun 2020, 2:35 pm	#4
TALKINGWITHPYE Pentode Join Date: Oct 2018 Location: Carrickfergus, County Antrim, Northern Ireland, UK. Posts: 126	Re: Jammed capstan sleeve Thanks for your replies, the screw head comes off easily but the sleeve won't budge. Ok on the oil suggestions, there is a bloke accross the street from me works on cars so he might have the automatic transmission fluid.

3rd Jun 2020, 2:40 pm	#5
TonyDuell Dekatron Join Date: Jun 2015 Location: Biggin Hill, London, UK. Posts: 5,208	Re: Jammed capstan sleeve Sometimes careful heating (hot air gun, hair dryer) or cooling (freezer spray) will get it free.

3rd Jun 2020, 2:43 pm	#6
DMcMahon Dekatron Join Date: Apr 2019 Location: Worthing, West Sussex, UK. Posts: 6,600	Re: Jammed capstan sleeve Holding/stopping the flywheel from turning maybe the key.

3rd Jun 2020, 4:56 pm	#7
saxmaniac Heptode Join Date: Oct 2007 Location: Birmingham, West Midlands, UK. Posts: 618	Re: Jammed capstan sleeve Why the witches brew for making lubricating oil? There's 3 in one type light oils readily available.WD40 is not much good for anything other than dispersing water and temporary protection against surface rust

3rd Jun 2020, 5:03 pm	#8
emeritus Dekatron Join Date: Jan 2012 Location: Brentwood, Essex, UK. Posts: 5,337	Re: Jammed capstan sleeve Plus-gas or, if you can't find some, petrol lighter fluid are extremely penetrating. Never had to do a capstan sleeve, but for badly rusted bolts and shafts, see-sawing the two parts to and fro will normally eventually pump fluid into the gap.

3rd Jun 2020, 5:09 pm	#9
ben Dekatron Join Date: Aug 2006 Location: Madrid, Spain / Wirral, UK Posts: 7,498	Re: Jammed capstan sleeve I'd be inclined to try the heating trick. Use the tip of a soldering iron. __________________ Regards, Ben.

3rd Jun 2020, 5:36 pm	#10
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,858	Re: Jammed capstan sleeve 3-in-1 is OK, but not a particularly strong penetrator it's a domestically benign light lubricant. Plus gas is good, but I haven't seen any on sale for years. Used to use a formulation from Morris's of Shrewsbury in the garage. The witches brew? well it's quite effective stuff. Do not use car engine type oils as general lubricants. I know, we all used to, but it now has a package of quite unpleasant additives to deal with combustion products and lead-based bearings. So Automatic transmission oil (which is also used as hydraulic fluid in power steering), is generally available and free from the nasties. It seems to only have an anti-foaming agent. The thinners is also generally available, thins the ATF and gets it into awkward places quite successfully. It also evaporates cleanly and leaves good lubricant behind. Just mind out for plastics and paint. David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

3rd Jun 2020, 7:03 pm	#11
vidjoman Dekatron Join Date: Jun 2013 Location: East Sussex, UK. Posts: 3,323	Re: Jammed capstan sleeve I have a feeling that this added sleeve is keyed and will not turn on the smaller shaft. It should lift straight up. Perhaps try a small screwdriver to lift it if there’s enough room between the sleeve and the deck.

3rd Jun 2020, 8:35 pm	#12
DMcMahon Dekatron Join Date: Apr 2019 Location: Worthing, West Sussex, UK. Posts: 6,600	Re: Jammed capstan sleeve Have not seen a keyed one before on the Akai 4000 range or similar Akai. I assume the 4000GS in Post # 1 is a typo, i.e. most likely should read 4000DS.

3rd Jun 2020, 10:05 pm	#13
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,858	Re: Jammed capstan sleeve 4000GS is a facelifted version with their Glass and Xtal head. Track switch moved out of head box as well. Tha Akai sleeves are not keyed an any way, but what most people don't notice is that the bottom end of the capstan had a conical flare as it steps up to a larger diameter. The sleeve has a slight conical rebate on its opening, so when it sits on the capstan cone-on-cone gives accurate centring The underside of the nut is flat and faces onto the flat face of the outer end of the sleeve. It takes decent precision to not have terrible flutter with a sleeve adaptor, and it's the 7.5IPS speed that bears the brunt. David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

3rd Jun 2020, 11:11 pm	#15
DMcMahon Dekatron Join Date: Apr 2019 Location: Worthing, West Sussex, UK. Posts: 6,600	Re: Jammed capstan sleeve Interesting, I have not seen the keyed/notched type before on Akai.

4th Jun 2020, 9:01 am	#17
red16v Heptode Join Date: Jul 2006 Location: Winchester, Hampshire, UK. Posts: 638	Re: Jammed capstan sleeve Various ways of fitting the resized capstan to the original. This website has some useful info. http://www.oaktreevintage.com/Akai_R...eplacement.htm

4th Jun 2020, 9:14 am	#19
Andrew2 Nonode Join Date: Mar 2010 Location: Dukinfield, Cheshire, UK. Posts: 2,036	Re: Jammed capstan sleeve I'd be very wary of using any levering method, you can so easily put a slight bend in the capstan and you'll never get rid of the wow/flutter. I came across bent capstan quite often when people had got a tape jammed in their cassette decks and the tape had wound itself tightly around the capstan. Instead of bringing the machine in for proper attention, they would attempt to force the tape out and the poor capstan bore the brunt! __________________ Andy G1HBE.