By continuing to use this site, you agree to our use of cookies. Find out more

Member postings for DC31k

Here is a list of all the postings DC31k has made in our forums. Click on a thread name to jump to the thread.

Thread: Reilang Oil Can Nozzle Thread
01/05/2022 08:01:02

The smallest BSP thread is 1/16" with an OD of over 7mm, so it might not be in that series.

There is a picture of spare parts for one model of can here:

https://www.ajreeves.com/12461.html

Please confirm it is the part bottom left of the picture.

Have you any known bolts that you can use as a thread gauge to judge the pitch? How have you determined it is coarser than 0.75mm pitch? What is the actual OD of the thread?

Cut the end off the delivery tube at the bottom of the internal threads and thread it a known, suitable internal thread (you are extending it, so just extend it 10mm more). Turn down the nozzle, soft solder on a plain sleeve and apply male threads to match the new internal ones.

Thread: Size of a Boxford metric Lead Screw
27/04/2022 11:07:03
Posted by Hopper on 27/04/2022 10:03:13:

But being metric, could it be a 30 degree Trapezoidal thread instead?

We have had discussions here before about metric leadscrews used on UK-manufacturered machines. Sadly, I cannot find one by searching, nor can I remember whether it was specific to Boxford or concerned another marque.

However, the consensus appeared to be that many of the manufacturers used imperial diameter stock and an ACME thread form for their leadscrews, just with a metric pitch.

It would be great if someone could find the thread just to refresh our memories.

Thread: Weird Collet Thread
27/04/2022 07:10:36

At the risk of over-egging the pudding, note that 10/12 pitch is 12 threads per centimetre; 15/12 is 8 threads per centimetre and 20/12 is 6 threads per centimetre. 1mm pitch is 10 threads per centimetre. Expressed in these terms, which are a close analogue of the way imperial threads are discussed, the pitches seem entirely reasonable and it is something like 1.5mm pitch that looks like an oddity.

Thread: Acme or not?
26/04/2022 19:06:00

If it is Swiss, is there a possiblity it could be metric, trapezoidal form? The dimensions are not so far off 14 x 3.5mm pitch.

How are you measuring the pitch? If you measure over 21 threads, do you get exactly 3 inches?

You would have to tell us what lathe it is in order for us to advise on gears.

Thread: What insert tool
26/04/2022 18:45:34
Posted by Dell on 26/04/2022 18:27:14:

...what about a chamfer tool holder ?

The CCMT insert is an 80/100 degree rhombus. Hence 'chamfering' can have two meanings. There is one on eBay that presents the insert 'straight ahead', which has the code SCMCN. That would give you a 40 degree chamfer. Glanze offer one that presents the insert at 45 degrees to achieve the conventional meaning of chamfer. Its code is SCSCR.

The codes you give are correct in principle. There is a 'C' missing from the right hand one (typo.). However, note that in a 10mm shank, the 'H' in the codes you wrote is the length of the holder (100mm). That is not so common in the smaller shank size, so you might have to change that letter to 'E' or 'F'.

Edit: the link you posted is perfect and also illustrates the shank length as 'E'.

Edited By DC31k on 26/04/2022 18:47:29

Edited By DC31k on 26/04/2022 18:50:30

Thread: Weird Collet Thread
26/04/2022 18:22:11

A curiosity of the W-series collet threads is that W10 is 10/12 mm pitch. W15 is 15/12 mm pitch and W20 is 20/12 mm pitch.

Against that, W12 is also 5/4 mm pitch, W25 is a true 15 tpi, and W31.75 is a true 20tpi.

See catalogue extract in post 2 here:

https://www.homemodelenginemachinist.com/threads/w12-collet-threads.8436/

There is also a Schaublin product catalogue from 1946 on Scribd (stamped with Wickman Machine Tools) that shows their E-series collets, the precursor of ER collets.

Thread: What insert tool
26/04/2022 18:14:05

The important bit from the littlemachineshop page is this: ISO: CCMW060204 HSS

That is the International code for the insert. The other code, the ANSI one, is used mainly in the US, but they are complete equivalents.

The carbide equivalent of the HSS insert is CCMT060204, so any holder that will take this insert code will fit what you have.

ArcEuroTrade's own brand holders and the Sumitomo brand they also offer will fit.

This page is good for the holder codes: https://www.cutwel.co.uk/blog/learn-the-turning-tool-iso-code-system

You will need to look for something that goes SCxChyyz06 where x is the holder style, h is the hand of the holder, yy is the shank height and width and z the length. The other parts of the code are specific to the insert used, which you already have, and thus do not have a choice.

For instance, a standard, right hand turning and facing holder with a 16mm shank would be SCLCR1616H06

Thread: Alternative Ways of Retaining Shafts
26/04/2022 15:31:11

Drill, tap, thick washer with countersunk fastening.

Thread: Weird Collet Thread
26/04/2022 15:27:51

That's the trouble with keeping those nasty decimal points in your head.

Think in terms of fractions and you see that 0.833 is 5/6 (of 1mm).

The W20 thread is more commonly expressed as 1.667, or in fractions, 5/3.

Change gears do not come in decimals. They come in integers. And the ratio of two integers is a fraction.

Thread: Colchester Student rear tool post adapter
26/04/2022 12:37:27

Make one.

A isometric general layout drawing will be in the manual for the machine. If you join the Colchester lathes io group, there is a dimensioned drawing of a Chipmaster one in the files section.

You know the width of the cross-slide, the spacing and thread of the holes to secure the plate to the cross slide (so you know the counterbore needed in the plate). You know the diameter of the T-bolts from the holes in the toolpost. Use those dimensions and scale any missing dimensions from the manual diagram. Put the toolpost on the cross-slide with a tool in it and work out how thick the plate needs to be to bring it to centre height.

You could fabricate it from cold-rolled plate, bolted together using countersunk screws if you did not want to machine or weld one.

Thread: DRO Z-Axis /4th axis "combiner"
25/04/2022 07:13:27
Posted by Neil Lickfold on 24/04/2022 23:08:17:

Is this possible?

In principle, yes. I think you would need to work (store) internally in the finer units, incrementing or decrementing by 1 when the fine scale changes and incrementing or decrementing by 5 or 10 when the coarser scale changes. It is the delt++ and delt-- lines above - they need slight modifications. 50% of them will be unchanged.

Then you would have to write a little bit of extra code that takes the number above and rounds it to the nearest graduation of your desired output, pondering over the situation where the value ends in 5 for the 10um position.

There may be an issue with the code above in that it does not cover the case where delt=0, only doing something when it is greater or less than zero.

Thread: ME handbook Capstan and Turret Lathes
23/04/2022 19:48:30

You could ask a Mike Waldron, who claims in this thread to have the pdfs...

https://www.model-engineer.co.uk/forums/postings.asp?th=149012

It is available on Abebooks:

https://www.abebooks.com//servlet/SearchResults?tn=Capstan+Turret+Lathes

Thread: Supplier of 7/32" Dowel Pins Please?
23/04/2022 10:02:08
Posted by Hopper on 23/04/2022 09:11:45:

Are drill blanks hardened all the way along?

Google is your friend...

https://www.icscuttingtools.com/Ground.htm (parallel)

https://docs.rs-online.com/742e/0900766b81585f5c.pdf (h8 tolerance)

https://www.mcmaster.com/steel-drill-blanks/ (lots of options)

https://www.ceratizit.com/int/en/offerings/hard-material-solutions/industries/tool-manufacturing/rods/drill-blanks.html (with coolant holes)

23/04/2022 07:54:13
Posted by B Tulley on 22/04/2022 21:28:29:
presumably those issues wouldn't apply to drill blanks - or would they?

The ones for which I found a price were off eBay, from Zoro. They are described as hardened and ground.

My guess is that they will be parallel, but I do not know for sure. You might have to ask Drill Service, suggested above, as they probably have better technical knowledge than Zoro.

It is a good question. As supplied, they are blank in both name and marking - so if one end was smaller than the other, the only way to find out would be to measure each end, and if you have ten jumbled up in a bag, that becomes rather tedious.

Thread: Hoover Motor wiring
22/04/2022 21:02:45
Posted by Howard Lewis on 22/04/2022 20:21:08:

You do not want to end up with the motor damaged, or yourself dead.

How would you damage the motor?

If you have four unidentified wires, a neutral and a live, go through all combinations and advise which one will lead to damage. A large number will lead to the motor not working (e.g. both ends of the same coil connected to live) but that is not a problem.

About the only thing I can think of is if two of the wires are ends of a common middle bit (i.e. no coil or capacitor in between). That would lead to a dead short, which would blow the fuse but still not damage the motor.

Again, on the killing himself part, repeat the exercise methodically and see how it is possible to produce a configuration where this is possible.

Thread: Supplier of 7/32" Dowel Pins Please?
22/04/2022 20:49:57
Posted by Howard Lewis on 22/04/2022 20:32:11:

As for chopping the end off the shank of a couple of 7/32" drills, the shanks won't be so short that they could not be used, would they?

No, but they will neither be hardened nor will they be 7/32" diameter.

22/04/2022 18:54:08

In the same vein as the silver steel suggestion, how about an HSS drill blank of the correct diameter (£3.19)?

Thread: Harrison m250
21/04/2022 07:47:13

There's a manual here: http://vintagemachinery.org/pubs/detail.aspx?id=18429 and on page 35 (904/2) it shows the pinion as integral with its shaft (so it is a kind of blind gear). That might have influenced the measurement they chose for the OD.

If you can measure the centre distance somehow (pitch line of the rack is halfway up the tooth), that might give some more information to ponder upon. An easy measurement is to go from the shaft centre to the rack tip, just to give you an idea of the absolute maximum root diameter that your gear can be.

Given that you are now faced with the challenge of stopping the new gear rotating on its shaft (key and keyway?) and securing it laterally (space on its inboard side for the projecting head of a fastener), the further from centre you can make the tooth spaces start, the more options you have.

I would also gang up three blanks and cut three gears, then you have spares for the future or in case something gets spoiled.

20/04/2022 07:51:22
Posted by JasonB on 20/04/2022 07:37:31:

....give you the MOD of the rack.

... and be cognisant of the possiblity that it might be a circular pitch gear (i.e the rack teeth spacing are an 'easy' number of units apart).

The numbers you give are hovering around 0.200" or 5mm circular pitch, but it is not possible to draw conclusions as the low number of teeth on the gear mean it may have been profile shifted as Jason suggests.

A very good, accurate measurement of the rack is your best way forward in this case. If it does turn out to be a CP gear, it would be wise to measure more than ten teeth as that makes it easier to distinguish whether it is imperail or metric (somewhere around 8" or 200mm would do).

Thread: A problem opening an old TurboBasic Help file
18/04/2022 09:18:49

A very good ploy with questions like these is to use the terms in a Google seach. There, you will find no information whatsoever associating TBF files with TurboBasic.

There is a searchable version of the TurboBasic manual here:

https://archive.org/stream/bitsavers_borlandBorsHandbook1987_15768512/Borland_Turbo_BASIC_Owners_Handbook_1987_djvu.txt

It suggests that the help files are .TBH extension (not .TBF). TBF does not occur a single time in the above manual. It also suggests they are help screens rather than help files.

TBH occurs 8 times, and at occurence number 5 & 6, it suggests you have to do something or other if you want to store the file in anything other than the default directory.

Magazine Locator

Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!

Find Model Engineer & Model Engineers' Workshop

Support Our Partners
Eccentric July 5 2018
cowells
Eccentric Engineering
Rapid RC
Dreweatts
Subscription Offer

Latest "For Sale" Ads
Latest "Wanted" Ads
Get In Touch!

Do you want to contact the Model Engineer and Model Engineers' Workshop team?

You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.

Click THIS LINK for full contact details.

For subscription issues please see THIS LINK.

Digital Back Issues

Social Media online

'Like' us on Facebook
Follow us on Facebook

Follow us on Twitter
 Twitter Logo

Pin us on Pinterest