Hi all,

I need to turn a perspex disk about 50mm dia. as a replacement speedo
glass on an old Yamaha. What can I use to stick in to a piece of wood
mounted in my lathe chuck?

Got to be something that will stick well enough for turning but come
off and not leave a mark...

Cheers for any suggestions!

Zed

"Zed Bert"  wrote in message 
news:6df42b3c-e822-48de-8a4a-6c56d2bd2f92@a32g2000yqm.googlegroups.com...
> Hi all,
>
> I need to turn a perspex disk about 50mm dia. as a replacement speedo
> glass on an old Yamaha. What can I use to stick in to a piece of wood
> mounted in my lathe chuck?
>
> Got to be something that will stick well enough for turning but come
> off and not leave a mark...
>
> Cheers for any suggestions!
>
> Zed

Blu-Tack?  It will hold pretty tight if even across the disc.

I would try double sided tape
"Zed Bert"  wrote in message 
news:6df42b3c-e822-48de-8a4a-6c56d2bd2f92@a32g2000yqm.googlegroups.com...
> Hi all,
>
> I need to turn a perspex disk about 50mm dia. as a replacement speedo
> glass on an old Yamaha. What can I use to stick in to a piece of wood
> mounted in my lathe chuck?
>
> Got to be something that will stick well enough for turning but come
> off and not leave a mark...
>
> Cheers for any suggestions!
>
> Zed

On 28 Oct, 22:30, Zed Bert  wrote:
> Hi all,
>
> I need to turn a perspex disk about 50mm dia. as a replacement speedo
> glass on an old Yamaha. What can I use to stick in to a piece of wood
> mounted in my lathe chuck?
>
> Got to be something that will stick well enough for turning but come
> off and not leave a mark...
>
> Cheers for any suggestions!
>
> Zed

PVA glue onto your wooden block
Sheet of drawing paper
PVA on the other side of the drawing paper
Perspex sheet held on until set.
Machine away, hot water to release.

Very old trick but works everytime with virtually any material.

John s.

On Wed, 28 Oct 2009 15:30:40 -0700 (PDT), Zed Bert wrote:

> Hi all,
> 
> I need to turn a perspex disk about 50mm dia. as a replacement speedo
> glass on an old Yamaha. What can I use to stick in to a piece of wood
> mounted in my lathe chuck?
> 

What I do is screw a square of plastic sheet to a wood base - that screwed
to the faceplate or mounted on a block held in a four-jaw.  Then I trepann
the disk out of the square (the screws are in the corners).  When I get
close I feed slowly and then remove the square and break the disk out when
the cut is almost through.  Clean up with a file.

Have done several guage and clock "glasses" this way.  Polycarbonate as
well.

"Zed Bert"  wrote in message 
news:6df42b3c-e822-48de-8a4a-6c56d2bd2f92@a32g2000yqm.googlegroups.com...
> Hi all,
>
> I need to turn a perspex disk about 50mm dia. as a replacement speedo
> glass on an old Yamaha. What can I use to stick in to a piece of wood
> mounted in my lathe chuck?
>
> Got to be something that will stick well enough for turning but come
> off and not leave a mark...
>
> Cheers for any suggestions!
>
> Zed

Use the tailstock with a ball bearing live centre, and a thick piece of hard 
rubber to press the plastic onto the wood. A few light cuts, and it's done. 
Only got a fixed centre? Use it to press a ball bearing onto a hockey puck 
or a piece thereof  to sandwich the plastic.


Steve R.