threads..

[stirling lad]

Ive just got a new mill and was hoping someone can help me understand something....
It has a R8 drawbar  but the booklet that came with it does'nt state what size the thread on it is supposed to be...It's a metric machine and i tried a m12 nut on the drawbar which fitted easily but most of the R8 tooling ive seen for sale on ebay say they are 7/16th UNF. My question is... are m12 and 7/16ths mutually compatible or does it have to be 1 or tuther?I know that ones metric and ones imperial but its just the sizes look very close on a ruler,,but the pitch of one thread may not allow the other,,So do i have to just make sure all my tooling is bought in metric?m12 drawbar thread ?Oh No!! ive just thought of a possible problem,,,,
Ok.. ive just answered my own question,,, and all the metric and imperial collets i bought must be 7/16ths as they dont join with the drawbar... :bang:So is it just a case of getting a 7/16ths drawbar now, then i'll have  both sizes covered?  or am i better getting a collet chuck..?

..Mike...

[Stilldrillin]

Heyup, young Man!

I've never come across R8 collets, with anything other than 7/16 UNF thread. Metric/ Imperial machine makes no difference.

Yer've got a bit of a mongrel there....... Unless anyone knows differently! 

Buy/ make, a 7/16 drawbar. To fit your correct collets..... 

Don't go buying a collet chuck!

David D

[hopefuldave]

I'd expect it to come with drawbars for both M12 and 7/16, but if it's a green one, the importer has a habit of taking offand stockpiling the.accessories that came from chiChina in the.crate, then selling them (drawbars and tilting vices on mills, the free basic tooling and spare bronze worm on power feed lathes, the T nut from QCTPs)...

[Fredbare]

I bought my R8 mill about 2 years ago, and it came with an M12 bar for the chuck, I had to make a 7/16 bar for the collets.

John

[Jonny]

Missing the point you use the drawbar to suit the thread in the collets being used.

The R8 collets are superb just check the thread in them.
Drawbars easy to make.

[stirling lad]

 Thanks for your replies guys,,
 So others have been given a 12mm bar too,,So maybe it was'nt accidental after all..

David,, i'll order up some wotzit bar/rod tomorrow,,

Dave,, its a blue one  and there was no free tilting vice with it,,,I wish there was...

John,, i think i'll be doing the same as you..and making one to fit...

jonny,, the mill and collets were bought at the same time on the assumption that the drawbar thread would a standard 7/16th like standard collets..

thanks again gents..

....Mike....
.....

[chipenter]

It may be easer to modify one from an other machine,  http://www.arceurotrade.co.uk/Catalogue/Machines-Accessories/Milling-Machines/Model-Super-X2-Plus-Mill/Super-X2-Plus-Mill-Accessories just a guess you didn't say what mill you have .

[Jonny]

Easier to buy a long HT bolt cut in half and a bit of steel round, weld em together job done.
Silver solder can be iffy even when jointed properly.

Just the one mill I had three different drawbars, M10, 3/8" BSW and M12, easy to swap over as in seconds.

[stirling lad]

Jeff,, its a realbull xj something or other I think,,, although it does'nt say that on it..
here it is... (my apologies for the poor photo quality.)


Jonny, I'm going to need at least 2 as ive now got 12mm and 7/16 stuff..

...Mike..

[Stilldrillin]

Oooohhh....... Belt drive, an all! 

You lucky, Lad...... 

David D

[stirling lad]

well I heard back from the nice man at SPG who sold me it today,,and 12mm is what they normally provide with this mill just the same as Amadeal do with the same mill,, but they have very kindly said they will send me a 7/16ths drawbar free of charge as well  so i can get started using it ...which i thought was decent of them . ..  ..Arceuro wrote back to say that 7/16 is the standard that they use for R8..I don't know why they all dont just stick to an agreed size.
but to be honest, ive found that almost everyone connected to model engineering in any way have been very helpful and often go that extra little way to help,....

thanks for all your replys..

...Mike...

[Stilldrillin]

Mike.
That was your first, "insurmountable" problem...... Now sorted!   

There's all the help you need, on here. You only need to ask.   

Enjoy your adventure. We'll support you, as you learn. 

David D