Screw mandrel supplier

[Faith]

Hi all,

Slightly random question, but any recommendations on where to buy screw mandrels from - specifically ones that are reliably the exact right shank size?

Since acquiring the Foredom all my Busch and Everflex burrs fit fine, but none of my screw mandrels do. They're meant to be 3/32, but obviously aren't exactly. (The Dremel was clearly more forgiving).

Rather than embark on a painful ordering and returning process I wondered if anyone had solved this problem already?

Many thanks :)

Faith

[Dennis]

Is it that they slip i.e. are too loose, or wont go in faith? It seems that the jaws of the chuck could do with adjusting to be more tolerant. There should be a way of doing this, or ask your supplier. Dennis.

[Faith]

Thanks Dennis,

They wont go in.

There are a couple of other threads I've read when I was researching motors that mentioned this problem, that foredom's with quick change snouts are fussy about shank size and that cheaper burrs and screw mandrels in particular may not fit.

To be honest I'm not sure I'm brave enough to adjust it just yet, and I do think the issue might be the screw mandrels - just looking at their shanks you can see lots of manufacturing variation that isn't there on proper burrs....

Faith

[J Allison]

http://www.moleroda.com/product/mm503-small-screw-top-mandrel/

[Dennis]

You might just investigate with your callipers too, faith.
On the rare occasions I have found a new one tight it was just distortion of the end , not of the whole shaft, so it could be cured by a little filing.
Dennis.

[Aurarius]

As Dennis says, the option of resizing oversized shanks is readily to hand. Even if the whole shank is evenly oversized you can take it down to an exact 2.35mm by inserting the threaded end into a standard household drill chuck and spinning the other end on to wet and dry paper until you reach the required caliper thickness.

I forgot to answer your first question, Faith. I bought thirty of the type of mandrel you're talking about in bulk from an Ebay seller about 18 months ago. They cost about 10-20 pence each, as far as remember. I thought they'd be iffy quality, but they seem reasonably well made. Badly made ones, apart from having shanks that aren't 2.35 mm, sometimes have inaccurately machined threads at the business end, meaning the retaining screw won't stay put whilst in use. It pays to examine every mandrel individually as soon as you get them and reject any that are defective.

[Faith]

Thanks Dennis, Mark & J Allison (sorry I don't think I know your name),

I think your right Dennis some are only too big at the non screw end, so I'll try the drill trick on the better ones. To be honest though I think they are badly made, I rejected a bunch because the screws didn't screw in at all, just fell back out, and some of those that started okay aren't wearing well.

J Allison - do you happen to use those yourself and recommend them?

Thanks
Faith

[J Allison]

Hi Faith its John and yes I use this company for lots of things