The BSA A7-A10 Forum
Technical (Descriptive Topic Titles - Stay on Topic) => A7 & A10 Engine => Topic started by: Chillipepper on 17.03. 2016 11:55
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Hi all
I am after a tap and die set for the above (engine and frame) any recommendations
Cheers
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http://www.tracytools.com/ (http://www.tracytools.com/)
are worth a look I've bought stuff from them that seems ok
as your looking at Whitworth and cycle threads, might save yourself a bundle buy just buying the ones you need rather than sets, sorry I'm not familiar with Plunger models although I suspect will be much the same as swinging arm. I'd think someone here will know just what are the common sizes you need
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yes RHCP, what Bill said, you really only need a few for frame and engine/g'box; 5/16" in BSC & BSW. On the Plunger, the only threads in frame I can think of easily are the seat pivot grease nipple 1/4"BSC, & (spring) mounts and steering damper/lock-lock (5/16" BSC). Engine/ gearbox castings use some same plus some 3/8"& 7/16" in , plates and through bolts/studs mostly 5/16 -3/8-7/16 BSC.
That's the easy bit
Tank bits and electrical bits use some BA and some BSF but not much......confused yet *conf* *????*
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all studs that go into alloy castings are BSW everything else is BSC which is 26tpi till you get to 1/2 inch which can be either 26 tpi or 20 tpi , have a look at some of the better bike jumbles like kempton where you can buy slightly used stuff in good nick for sensible money , beware of bodger using a metric fine bolt which is a 1mm pitch and is very close to 26tpi and can be forced to fit!!! seen a few of those and is a right pain to fix
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I've bought and used an Indian set of cycle taps off E--y. And so far so good on mild and stainless steels.
http://www.ebay.co.uk/itm/BSB-26-TPI-CYCLE-THREAD-TAP-DIE-SET-1-4-TO-1-2-20-PCS-SET-VINTAGE-BIKE-CAR/322039755587?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D20140122125356%26meid%3D2700fa39cc8f433394b34f63b32c7853%26pid%3D100005%26rk%3D1%26rkt%3D2%26sd%3D322011125523
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Good address also is;
http://www.rdgtools.co.uk/
They have left hand taps and dies which you may need if the left footrest stud and/or nut are butchered.
Some stuff I got from Chronos which is also good quality;
http://www.chronos.ltd.uk/
I ordered what I needed as I got along through the restoration. Allowed me to buy somewhat better quality without hurting my wallet to much.
As duTch mentioned you'll need WW for the engine, 3/4 X 20TPI for the cush drive and BSC for most frame bolts. You'll also need some BSF for the cylinder head. If my memory serves me well, it's 5/16 for the rocker box bolts, and 3/8 for the head bolts
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They have left hand taps and dies which you may need if the left footrest stud and/or nut are butchered.
That's the one I undo most often, just the other day in fact; How could I forget thatone *bash*
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That's the one I undo most often, just the other day in fact; How could I forget thatone *bash*
Don't be to hard on yourself duTch. We're all getting older *smile*
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I've had a Tracy Tools supplied 26 tpi tap and die set for many years and added other single items as required. It's worked fine for me.
I bought the 26 tpi set before TT moved out of Isleworth. As I said - many years.
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I've had a Tracy Tools supplied 26 tpi tap and die set for many years
I don't wanna split hairs, but someone has to; Is it 26 tpi BSC or BSF *????*
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Hi dutch,
I don't wanna split hairs, but someone has to; Is it 26 tpi BSC or BSF
The 1/4in size in BSC and BSF are both 26tpi, there are detail differences in the thread form
othere than that BSC and BSF are different (to the best of my knoowledge
Spend a week studying this and report back ;)
http://www.gewinde-normen.de/en/index.html
John
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Spend a week studying this and report back ;)
NO. *eek*
Yes the threadform was what I meant. Not that I haven't ignored that at all, oh no. But was only more recently I learned the difference, and earlier, BSC taps and dies were not available to me. *spider*
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In simple terms, the biggest difference in form is the included angle on the various threads, with the 'whitworth' angle - for all BSW and BSF - being 55°.
BSC is 60°, so are UNC and UNF, and most if not all metric, while BA is 47.5°.
There are differences in roots and crests and stuff which the long read referenced and other similarly scholarly sites explain in horrible detail, along with the important stuff like 'how many threads to the inch' (or millimetre equivalent) for a given size.
Some series overlap on the pitch/threads per inch, like M6 and 0BA at 1mm, or 1/4 Cycle and BSF at 26 tpi, and a few UNC and BSW sizes share their tpi.
But for a '50s beesa it's going to be mostly BSC, a bit of BSF, some BA for the electrical side and maybe (trying to think of something) BSW. Except where POs have decided on something else . . . which they often might have. Plumbing sizes for fuel taps and unions - BSP (whose sizings are done on the bore of what is to be screwed into them, so they sound far smaller than they are).
I'm with Terryg - Tracy Tools for the basics and add when required. Decent enough quality, fair prices, rapid service, I have always found, and a huge range.
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It goes like this as previously stated the difference is the angle between the threads and this is important as when a narroe angle and a wider angle thread form have the same numbers of threads per inch, the narrower one is cut a lot deeper so while 1/4 Brass , CEI , BSF, & conduit all have the same number of threads, some are deeper than others.
So shoving a BSF bolt into a CEI hole makes the thread deeper so when you screw a CEI bolt bolt back in latter on it will be loose and either pull out , strip the remaining thread out of the hole or simply just vibrate loose & fall out.
This is hard for most to visualise so try cutting a sheet of paper with a series of 47.5 , 55 & 60 degree Vs.
Then place one set into the other and you will see that to fit, the softer material has to get deformed.
I did an bit about it for the Banter years ago.
BSF & BSW both have the same thread angle but if you look at 2 of them that are the same size you will see the fine thread is less than 1/2 the depth of the coarse thread.
Finally if you are going to be working on Pommie bikes you will be better served by purchasing individual sizes.
Generally individual sized sets of taps ( Tapper, inter & plug) will be of better material than a 40 piece set.
Also individual dies are generally split type so you can make the thread a bit tighter to compenste for past butchery.
Somewhere in the UK or USA parts books ( not the multi language general export editions ) is a table of standard sized bots used on your bike.
These are the sizes you will need.
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all studs that go into alloy castings are BSW
Actually, correct me if I'm wrong as I have a variety of screws in the inspection covers of the various spare gearboxes I have, but I reckon most are BSC. These are ones that I (erroneously? 'as above') used Unbrako BSF socket cap screws in many years ago*shh*.
When I go to buy Whitworth bolts/nuts from a bolt shop (getting few and far between around here), generally I end up with what must be UNC, as the hex is the wrong size. I try and double check with the guys, but they don't always (usually don't) know the difference.
So when buying 'Whitworth' Socket cap screws, do we buy WW or UNC ??
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Because eg BSW and UNC 1/4 at 20 tpi and 5/16 at 18tpi are the same bar the thread angle, I suspect some people sell the latter as both.
Hexes on BSW should fit best into BSW/BSF weapons - though, again, there are close matches across spanner series too. But then, yet again, I have seen hybrids with BS pitches and AF heads - but no idea where such things have come from. My A had several head bolts like that when I first got it. Tis a minefield!
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If you are going to fit UNC then you really should helicoil the holes to the correct thread .
The best place for WW now days are boating shops
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The best place for WW now days are boating shops
Funny you should say that TrevorTrev, I buy a lot of stuff from my local boaties kinda who I had in mind, https://www.whitworths.com.au/ (https://www.whitworths.com.au/)
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Yes and if you go stainless, most of the bolts will be cut so the shaft size will be the major diameter.
Thus I buy a WW bolt that is too long, cut the WW thread off and cut a CEI one on the shaft.
Older bikes have WW in the alloy and CEI into metal and for all tinwear.
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I do the same for ww/cei studs. Cut the head off the ww bolt and cut the cei thread.
Cheers