Question about GHT’s retracting topslide drawing

This topic has 8 replies, 4 voices, and was last updated 29 August 2026 at 23:09 by John Purdy.

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29 August 2026 at 16:01 #862716
ega
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@ega
I bought the kit from the late Neil Hemingway but have only recently plucked up the courage to start the build. In his Workshop Manual (1992 edition) GHT said that, apart from the gears and leadscrew which come with the kit, the parts are not difficult to make, but I think I took fright when I saw the Double Elephant size drawing! I know that one or two members have successfully completed the RTS and hope for some help with the drawing of the body as shown in the extract below:

Holes A to E are shown and listed in the table but two holes on the drawing appear not to be listed and I am not clear about hole F. The unlisted holes have coordinates of 1.218/.512″ and .600/1.625″; one of them may be F.

Can anyone who made the RTS throw any light on this? I am reluctant to think that GHT slipped up and appreciate that I may be misunderstanding the drawing.

Incidentally, apart from Neil Hemingway’s business being taken over on his death, it now appears to have passed to Messrs Reeves and I don’t suppose they could help at this remove.
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29 August 2026 at 16:17 #862726
JasonB
Moderator
@jasonb
A lot of the Hemmingway stuff was redrawn in CAD, Reeves may be able to help with a more upto date drawing. You can see the CAD drawing here https://www.hemingwaykits.com/HK1240

Failing that what mates with the two unlisted holes?
29 August 2026 at 17:16 #862727
ega
Participant
@ega
JasonB:

Thank you for your advice and for the link which, however, seems to show only drawing 1 of 6, the GA; I will try Reeves – happily, they are still with us!

I did consider your fallback suggestion and may have to have another go at this route. I also thought about just diving in but am reluctant to start cutting metal without having a clear path to the finished product.
29 August 2026 at 18:04 #862730
John Purdy
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@johnpurdy78347
I made mine about 15 years ago and looking at my drawings they appear to be different. On mine your hole .6/1.625 is listed as “G” and the other is the centre of the large .875 dia hole. see the attached drawing. Hole”F” would appear to be the one on the curved surface as shown on the drawing below at the botom left.

John
29 August 2026 at 19:50 #862743
bernard towers
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@bernardtowers37738
my drawings are the same as Johns and the RTS has been working fine for the same period, I would suggest you use the drawing John has scanned. Dont forget that the drawing keeps getting inverted and rotated this can be awkward as there are quite a few dims in a small space. Well worth the trouble though IMHO
29 August 2026 at 20:29 #862749
ega
Participant
@ega
Gentlemen:

Many thanks indeed for your help. It looks as though I shan’t have to trouble Reeves and can now start cutting metal.

My large drawing is no WE23 from MAP Ltd and appears to be identical as to content to the drawings in GHT’s book. Interesting to see how the CAD dimensioning method differs from the traditional. I was initially puzzled by the double headed arrow of the latter.

Jason pointed me to Reeves’ website where there is a photo of the finished RTS; whoever made it seems to have set the bar rather high! I shall be happy if I can get mine to work.
29 August 2026 at 20:48 #862759
John Purdy
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@johnpurdy78347
Hole “F” by the way is to allow access to the eccentric bush that one of the gears run in to, using a small pin, to rotate it to adjust the backlash in the gear train. After adjustment the bush is locked with the 6BA set screw just above hole”F”. I agree with Bernard, it is well worth making, makes screw cutting so much easier and faster. One thing I have noticed on mine ( which may be my manufacture) is that the over lock on the forward motion of the slide is not sufficient and it tends to move back if bumped. The use of GHT’s slide lock mod to the top slide works to stop it from moving.

John
29 August 2026 at 22:56 #862767
ega
Participant
@ega
John Purdy:

Thanks for the further information and photo. I dowelled and locked my topslide some years ago and hope to avoid the problem you mention.

I look forward to easier screwcutting!
29 August 2026 at 23:09 #862771
John Purdy
Participant
@johnpurdy78347
Another advantage is the much larger feed screw dial, now graduated in thous instead of 2 thous, with its ability to be unlocked and reset easily without fear of the the top slide moving.

John
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