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badgaz
15th Sep 2009, 10:19 PM
Hi folks
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One of my other hobbies is painting miniature figures. I thought I'd combine my new love for wood turning with my long time hobby of scale modelling.<o></o>
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I would like to turn some wooden bases to display some of my figures and smaller models but, I'm unsure as to how to mount the blanks to turn them.<o></o>
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The wood blanks are 140mm x 140mm square and 40mm deep approx (mixed species hardwoods).<o></o>
I need to mount them without leaving tell tale screw holes (such as with a face plate or screw point in a chuck).<o></o>
Could I theoretically cut off the corners and mount the blank between centres to bring it into round (like a very short spindle piece), then cut a tennon or a recess for the scroll chuck and finish the work that way?<o></o>
I would like to preserve as much of the height (40mm) as possible so a shallow recess may be alright as it won’t be seen on the underside.<o></o>
I could turn a short tennon and mount it to my VM100 chuck, but since I only have the standard jaws, if the diameter of the finished base is too wide for the scroll chuck how do I reverse the piece to square off this tennon?<o></o>
I could glue the stock to a waste block and turn from there but I have not attempted that before and wouldn't know where to start, or how to take off the waste block and clean up when done.<o></o>
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I've included a pic I found on the web of what I'm trying to achieve. I hope you can help.

Regards
Gazza

Skew ChiDAMN!!
15th Sep 2009, 10:38 PM
For something this size, it's probably best just hot-melt glued - or double-sided taped - to a faceplate.

Personally, I'd salvage the head out of an old VCR and glue it on as a stub for holding in a chuck. These can be "pre-heated" in a fry pan, so the glue stays melted longer, allowing you to get a good glue up. And separating is just a matter of either re-heating in the fry pan.

With this method you can't use a friction finish, though.

mick61
15th Sep 2009, 10:44 PM
G`day Gazza the simplle solution is carpet tape(double sided). First attach a blank of pine about 160mm square to a face plate. Turn to round and face of so you have a flat surface place carpet tape on to the pine blank don`t go overboard this stuff is strong just put four squares evenly across the blank. Attach your hardwood blank then place a small dowel in the center and bring up the tail stock this will hold very well while you round the disc.When you come to face of the top of the disc remove dowel and tail stock.
Hope that is slightly clearer than mud.
Mick:D

Hey skew you type fast

Ed Reiss
15th Sep 2009, 11:21 PM
...of course you could go the expensive route and rig up a vacuum chuck; if your needing a lot of bases the investment might pay for itself in saved time.

hughie
16th Sep 2009, 01:17 PM
Hi Badgaz,

What I have done in the past is to fit/glue a sacrificial block turn one side, flip it over and do the reverse.
But I think Skews idea of old VCR Heads is the pick of the bunch, Especially if you rough up the surface to the VCR Head and use hot melt.

When looking for hot melt bare in mind there is some variation in quality and strength.

badgaz
16th Sep 2009, 02:57 PM
Thanks gents

I guess that's a NO to making the roughing cuts between centres:B.

I'll have to say g'bye to any friction finishes too.:doh:

Fresh out of old VCR's, what about gluing a small faceplate ring (50mm)? I could afford one of those over a vacuum chuck at this stage. But considering the amont of interest shown by members of the ACT scale modelling society, I could go into production and recover my costs and then some.

I reckon if I glue up a waste block I could complete the top and then flip it over, press it into a jam chuck, part off the block and clean up the base. This would be a series of firsts for me.

Cheers

Gazza

Skew ChiDAMN!!
16th Sep 2009, 03:39 PM
I guess that's a NO to making the roughing cuts between centres:B.

I wouldn't, for several reasons but mainly 'cos removing the "dings" left by the head- and tail-spurs would cause you to lose too much thickness. Unless you either glued on sacrificial pieces - making it more complicated - or back off the pressure so much that the piece is likely to turn UFO.

You could mount a faceplate instead of the drive-spur and rely on pressure from the tailstock & friction to spin the piece, not worrying about the "ding" the spur'd leave in the base. But that's not really a good method either, except for certain circumstances. (Mainly when you have no other real choice. :;)

No old VCR's, eh? Pity, they work so well. A faceplate ring would do the job, but being iron will take longer to cool down. Plus they're a tad expensive for what they are. Still, if you already have one...

I'd just glue on a stub tenon maybe with a sheet of brown paper in the glue-joint to make it easier to separate. Then turn the edge and bottom, break the glue joint and simply scrape off/sand the top by hand before finishing.

Assuming the top is flat, of course. I'd only bother with a jam chuck if things go a bit wrong and it has to have the top surface turned clean.

Good luck with it, whatever way you choose to go! :)

badgaz
16th Sep 2009, 04:31 PM
Thanks again Skew



I'd just glue on a stub tenon maybe with a sheet of brown paper in the glue-joint to make it easier to separate.


Given the diameter of the blanks are about 140mm and I'll probably turn these down to 100mm or less, what would be a fair size for the stub? 50mm dia. or more? Also, if I'm going to mount it in the VM100 chuck should the stub be as deep as the standard chuck jaws so that the base of the blank buts up against the rim of the jaws?:hmm:

help

Gazza

Skew ChiDAMN!!
16th Sep 2009, 05:23 PM
Given the diameter of the blanks are about 140mm and I'll probably turn these down to 100mm or less, what would be a fair size for the stub? 50mm dia. or more? Also, if I'm going to mount it in the VM100 chuck should the stub be as deep as the standard chuck jaws so that the base of the blank buts up against the rim of the jaws?:hmm:

A std. 45mm dia. tenon should do the job nicely. (Or whatever the size is when your jaws form a perfect circle.)

It shouldn't be quite as deep as your jaws; you don't want the tenon "bottoming out" in the chuck. That can cause problems with "out of square" if you need to remount for some reason.

TTIT
16th Sep 2009, 06:35 PM
When I saw the words "miniature" and "scale modeling", I guessed these thing were only about 30 or 40 mm diameter but it sounds like they're going to be between 100 and 160mm'ish ??? yes/no ???:?
If they're even 70mm diameter or bigger, I would be slapping them on the drill press and using a Forstner bit to cut a shallow recess to suit your standard jaws and mount them that way. It will give you clearance from the chuck to mould the rim any way you like and it's quick, clean and easy. The Forstner hole would only need to be about 4 or 5mm deep and wouldn't look too foul :shrug:

badgaz
16th Sep 2009, 08:04 PM
it sounds like they're going to be between 100 and 160mm'ish ??? yes/no ???http://cdn.woodworkforums.com/http://cdn.woodworkforums.com/http://cdn.woodworkforums.com/http://cdn.woodworkforums.com/images/smilies/standard/confused.gif
Thanks TTIT

I work with a range of figures from 54mm (1:35ish) up to 120mm (1:16ish) add a little ground work, or a few figures (vignette) and your looking at a platform that needs to be anywhere from 50mm to 100mm in diameter.



I would be slapping them on the drill press and using a Forstner bit to cut a shallow recess to suit your standard jaws and mount them that way.


That seems to be a reasonable compromise. A 50mm forstner should do the trick. I should try that and the gluing method to get a feel for both. The forstner solution would save time in a production sense.

Many thanks gents for your great advice.

It's not woodwork ( but there is wood in it), here's a 70mm conquistador I completed a while ago, white metal figure, painted with oil paints...and a steady hand.:D

Sawdust Maker
16th Sep 2009, 08:40 PM
looks like my ex father-in-law :roll:

RETIRED
16th Sep 2009, 10:42 PM
All the previous suggestions are good.

The way we have done a similar job with trophy bases is to glue a piece of sand paper to a face plate and fit a wooden "push" block in the tail stock centre.

It is preferable that the "stuff" has the corners taken off to form an octagon and that the cuts are done with very sharp tools with deft hands to avoid too much slippage.