Mystery 3/8 BSF
Geoff Mathews | 07/12/2020 17:55:55 |
![]() 33 forum posts 6 photos | I have two Flexispeed lathes, a Norfolk and a Meteor II. On the under side of both centrally in the base casting there is a hole tapped to 3/8 BSF. What is the purpose of this - it can not be tightened from above because the feed screw is in the way. Is it for some sort of location device? - Thanks Geoff. |
Geoff Mathews | 07/12/2020 17:57:33 |
![]() 33 forum posts 6 photos | I meant to say "base casting of top slide". |
Neil A | 07/12/2020 21:17:25 |
160 forum posts | I have just been out to look at the top slide of my Flexispeed Meteor 2 lathe, on my model this hole is tapped 1/4 x 20 UNC. I don't know what the intended purpose of the hole is, but the metal is only about 5/32 thick so only a few threads of engagement, not really enough for most purposes. Perhaps it could be used in conjunction with an angle plate to give a light vertical slide, my top slide has 4 tapped holes under the tool post. Tomorrow I'll check and see if they line up with the holes in the machine vice and angle plate that they supplied, it's only a guess mind you. There is no reference to it in the assembly or operating instructions. It could just be part of the manufacturing process. My lathe came as a kit of parts from the Norfolk Lathe and Tool Company Limited at Royston House, North Walsham in the early 1970's. The thread system on my lathe is all UNC. As the lathe has been made by a number of different companies during it's lifetime, you may find other thread systems have been used, you have to check carefully. The usual giveaway is the diameter of the threads for the gib strips, (6-32 UNC and 4-40 UNC) and the setscrew for the tailstock offset, (1/4 x20 UNC). Neil |
Geoff Mathews | 08/12/2020 15:55:07 |
![]() 33 forum posts 6 photos | I also am unable to find any reference to it in either assembly or operating instructions. I find it difficult to hold the top slide in place by means of only the solitary cap screw. I have found some benefit in using a short screw beneath the top slide to prevent the top slide from rotating around the car screw. I feel as if I am missing something here. |
Neil A | 08/12/2020 21:23:05 |
160 forum posts | I checked the 4 holes in the top slide, they are tapped 2BA on a 15/16" PCD centred on the 1/4 x 20 UNC hole for the tool post. The angle bracket is quite small, 1.75" on the long leg and 1" on the short leg and 1" long. The long leg has a central 1/4" diameter hole and 4 holes 3/16 diameter on a 1" square pattern centred on the 1/4" hole. The short leg has 3 holes 3/16" diameter in a line spaced 7/16" each side of the centre one. The bracket shows signs of being used, but I cannot remember how I used it. The vice has 2 holes 3/16" diameter on 15/16" centres, which would fit on the top slide, but not the angle bracket !! I have no idea what the original intention was with these parts, I always juggled the setup to suit what I needed at the time. I also found the original single 1/4 x 20 UNC capscrew holding the top slide assembly in place a bit of a problem to keep tight. On my machine, for a particular job, I fabricated a longer cross slide from some cold rolled steel plate and I tapped all the holes in it 2BA, This means that I am only using a 2BA capscrew to hold the top slide in place and I have not had the same problem. There could be a variety of reasons for this, but I think it may be that the 2BA capscrew has a 1/2" long spacer giving it a longer stretch length and so holds the tension better than the short 1/4" capscrew. I could be wrong though. Neil |
jason shaw | 27/12/2020 21:03:15 |
13 forum posts | guys i know nothing of metalwork but i was given an old flexispeed, i know that my spindle thread is 1/2" 16 bsf, i thought about mounting the spare chuck on a base so i went out and bought a 1/2" x 16 bsf die but it doesn't fit the chusk, is there some formula to match an internal thread to an external bsf fitting?
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Howard Lewis | 28/12/2020 16:39:19 |
7227 forum posts 21 photos | Jason Shaw Maybe the die needs to be tightened a little to cut a deeper thread. Can you carefully screw the die onto the Mandrel,(so that it does not cut ) and then tighten it so that it just grips the mandrel? That should give you a setting so that a "finishing" cut on the base, would allow the chuck to be mounted. Howard |
Geoff Mathews | 31/03/2021 21:43:56 |
![]() 33 forum posts 6 photos | I am dissatisfied with the top slide on my Meteor. I am contemplating fitting a late Perris/Cowell saddle and slides. Has anyone else been down this route? Edited By Geoff Mathews on 31/03/2021 21:46:07 |
James Alford | 31/03/2021 22:01:30 |
501 forum posts 88 photos | I am intrigued by what aspect of the top slide that you find unsatisfactory. James. |
Michael Gilligan | 31/03/2021 22:18:49 |
![]() 23121 forum posts 1360 photos | Posted by Geoff Mathews on 07/12/2020 17:55:55:
[…] there is a hole tapped to 3/8 BSF. What is the purpose of this - […] . My guess [and that’s all it is] is that it was used for location/hold-down purposes during manufacture, and is irrelevant to the user. ....Try working out how you would machine the top-slide details without it. MichaelG.
Edited By Michael Gilligan on 31/03/2021 22:19:40 |
Geoff Mathews | 01/04/2021 11:22:11 |
![]() 33 forum posts 6 photos | James I like Flexispeed lathes as they are pleasingly rigid and accurate for such a small lathe. My lathe is fitted with a tiny motor with integral 19:1 gearbox which does away with the necessity of a countershaft. The maximum output is 400 watts at 500rpm. The lathe and motor assembly really is light and portable. This is very important to me as I live on a canal boat.
My lathe is the screw cutting version with a hand finished bed. I like the gearing arrangement with allows me to go directly from to screw cutting to very fine automatic feed without the inconvenience of changing any gears and vice versa. The coarse pitch of the lead screw at 8 tpi makes life without a half nut easier as it is only a few turns to get back to where I want to be. The combination of these features leads me to the conclusion that I would not want to exchange it for any other comparable small lathe.
I feel the means of attachment of the top slide in the way it is bolted down on one side only lacks sophistication. That is why I am contemplating a late Perris/Cowell type saddle and slides. I am aware that the centre height on my lathe is ¼ inch higher. A larger cross slide would also present some interesting opportunities. I am hoping that others might have had similar thoughts and ideas regarding transplating such a saddle and slides to a Flexispeed lathe. Whilst we are on this subject I would like to learn more of the relationship between Brian Perris and Flexispeed. It seems to me that they were competing for the same market. Yet Brian Perris ended up with the Flexispeed design. I have been in touch with Tony Griffiths and I do not think that there is any more information available from that source. |
Hopper | 01/04/2021 12:51:04 |
![]() 7881 forum posts 397 photos | +1 on something used to hold the casting during the factory machining process. That would be my guess also. |
James Alford | 02/04/2021 09:19:06 |
501 forum posts 88 photos | Geoff: are you are referring to the compound slide which is used to turn tapers? If so, my Flexispeed came with an aftermarket version which is secured by central screw rather than a lug and a screw at the side. It is not the most robust piece of equipment that I have seen, but it does stay securely in place when being used. Or am I completely misunderstanding your question and the problem? James. |
Michael Gilligan | 02/04/2021 09:48:34 |
![]() 23121 forum posts 1360 photos | Posted by Geoff Mathews on 01/04/2021 11:22:11:
[…] Whilst we are on this subject I would like to learn more of the relationship between Brian Perris and Flexispeed. It seems to me that they were competing for the same market. Yet Brian Perris ended up with the Flexispeed design. I have been in touch with Tony Griffiths and I do not think that there is any more information available from that source. . Although you have probably seen this already, Geoff: I think it worth linking here **LINK** http://www.lathes.co.uk/perris/ My understanding [limited as it may be] is that Brian Perris ‘adopted and adapted’ the basic design of the Flexispeed, To quote from that page : “Mr. Perris began by making his own wooden patterns, based on the Flexispeed lathe he was then selling as kits of parts - a friend having bought the company.” MichaelG. . P.S. __ I have a ‘Jason’ lathe, which is a delightful little thing. The early demise of Mr Perris was a great loss to the evolution of small lathes. |
DiodeDick | 12/04/2021 11:29:24 |
61 forum posts 10 photos |
i bought a basic kit from Norfolk, for £72 in 1976. There was quite a time lag between paying the deposit and taking delivery, so I did not risk any further purchases from Norfolk, lest my money disappeared into the receiver's hands. The literature supplied was Flexispeed, over stamped Norfolk. First job after the kit was built was to add a back-gear, using gears from a defunct valve actuator. Then I added a Cowell fine-feed and screw-cutting attachment. This wee lathe screw cut quite a few 26tpi cycle thread motorcycle parts. Eventually I upgraded to an ex-industrial ML7R and sold the Norfolk. I sometimes wish that I had kept it, as a momento. To fit the Threading kit I had to bore out the left-hand leadscrew bearing using a spot facing tool, built to LBSC's words and music. That is it fitted to the long bolt at the bottom of the photo, then make an adaptor screwed 5/16 whit Left Hand to screw into the hollow mandrel. Mark 1 adaptor at the top of the photo - Mark 2 had a longer body, to get the gears to line up... All in all, it was good fun and I got a lot of value from it. |
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