The BSA A7-A10 Forum

Technical => A7 & A10 Engine => Topic started by: Stephen Arsenal on 14.10. 2009 21:01

Title: Screw sizes for pair shaped BSA Logo A 10 Fuel Tank.
Post by: Stephen Arsenal on 14.10. 2009 21:01
Hi can anyone know the screw width and length they mus be quite thin ??? thanks
Title: Re: Screw sizes for pair shaped BSA Logo A 10 Fuel Tank.
Post by: A10Boy on 14.10. 2009 21:13
They are a BA size, don't remember which, either 2 or 4ba.
Title: Re: Screw sizes for pair shaped BSA Logo A 10 Fuel Tank.
Post by: Desburnett on 14.10. 2009 21:26
Hi,
The screws are 3BA and need to be 3/4" long under head.
I came to fit my badges this last weekend that came with screws only to find out they were too short to even protrude through the badge.

Des
Title: Re: Screw sizes for pair shaped BSA Logo A 10 Fuel Tank.
Post by: LJ. on 14.10. 2009 22:17
Its a funny thing seeing this new thread as I fitted some pear shape badges only this morning but with horrible rusty screws... I'm wondering if they are available in 3BA brass, anyone know if they are about?
Title: Re: Screw sizes for pair shaped BSA Logo A 10 Fuel Tank.
Post by: Desburnett on 14.10. 2009 22:45
You might find them in an old style electrical store but they are like rocking horse droppings. Probably more chance of picking up stainless ones from one of the stainless specialists that exhibit at classic shows. Stafford Classic bike show is on this week-end and I believe Kempton Park the week after.
Title: Re: Screw sizes for pair shaped BSA Logo A 10 Fuel Tank.
Post by: chaterlea25 on 14.10. 2009 22:51
Hi All,
3BA is within a gnats whisker of 4mm x 0.7
mostly they will interchange, *ex* *ex*
Cheers
John
Title: Re: Screw sizes for pair shaped BSA Logo A 10 Fuel Tank.
Post by: Stephen Arsenal on 15.10. 2009 14:30
Great,thanks,just bought 2 4.45 mm screws,fit like a glove, er but is that secure enough,or shpould i glue them /and rubbers as well against exrta vibtration or the local pear shaped BSA logo thieves.Another quick qustion,how thick is the red boarder that is betwen the chrome and painted area of the petrol tank  ? 5 mm ??
Title: Re: Screw sizes for pair shaped BSA Logo A 10 Fuel Tank.
Post by: trevinoz on 15.10. 2009 20:59
Stephen,
               I guess you mean the pin striping between the main colour and the chrome.
3mm would be plenty wide enough.
Use a bit of loctite on your badge screws, not the high strength stuff.
Trev.
Title: Re: Screw sizes for pair shaped BSA Logo A 10 Fuel Tank.
Post by: BSA_54A10 on 16.10. 2009 10:01
And put an O ring under the head to stop you cracking the head when you tighten the screw too much.
ISO metric and BA thread profiles are nothing like each other but as there is no load you might get away with it.
There is more to threads than just having the same number of threads.
If you over tighten the screws then you will tear the tips off the BA thread, rendering the hole unuseable so please be careful
Title: Re: Screw sizes for pair shaped BSA Logo A 10 Fuel Tank.
Post by: A10Boy on 16.10. 2009 15:07
If you search any of the stainless steel screw suppliers on ebay, they will get the right BA screws to your door without you even having to leave your armchair.
Title: Re: Screw sizes for pair shaped BSA Logo A 10 Fuel Tank.
Post by: trevinoz on 17.10. 2009 04:48
I don't know about the rest of the world but here in Oz the odd size BA screws are out of production. The even ones seem to be fairly easy to come by.
By the way, Domiracer had the 3BA screws listed in their last special poster.
Trev.
Title: Re: Screw sizes for pair shaped BSA Logo A 10 Fuel Tank.
Post by: Stephen Arsenal on 18.10. 2009 20:29
Stephen,
               I guess you mean the pin striping between the main colour and the chrome.
3mm would be plenty wide enough.
Use a bit of loctite on your badge screws, not the high strength stuff.
Trev.
Thanks for the info,is the red pin stripe a transfer or must it be painted on ??
Title: Re: Screw sizes for pair shaped BSA Logo A 10 Fuel Tank.
Post by: trevinoz on 19.10. 2009 03:33
The pin stripe originally was hand painted. It's not easy to find someone to do this nowadays.
You will find tape on a lot of them now.
Another way is to spray the line colour and mask it while the main colour is sprayed.
Trev.
Title: Re: Screw sizes for pair shaped BSA Logo A 10 Fuel Tank.
Post by: LJ. on 19.10. 2009 10:10
Actually lining by hand is not that hard to do if you have the correct brush and steady hand! These pure sable whip liners I've had since I was eighteen as an apprentice painter but only just used them after many years of storage. There is no doubt that hand lining gives that special touch with older bikes but I'd think that by the time the mid fifties and early sixties had arrived, tape would have been the norm.

With paint you get a better flow at the edges where with tape you get a sharp edge, you can see that edge under the gold paint in the photo where I masked between the silver and red paint.

(I know... I like chrome but I'm selling this tank on soon.)
Title: Re: Screw sizes for pair shaped BSA Logo A 10 Fuel Tank.
Post by: bsa-bill on 19.10. 2009 10:54
It's the very slight imperfections in hand lining that give it the edge for me, just love it.
Bit like that woman singing "Wild Horses" in an operatic type voice, now that song needs to be sung badly, Mick did it justice.

All the best - Bill
Title: Re: Screw sizes for pair shaped BSA Logo A 10 Fuel Tank.
Post by: BSA_54A10 on 20.10. 2009 10:56
IF I can find it I will post the advert from Pride & Clark for a pin line painter.
Basically a roller with interchangeable heads