A few silly questions: making small round bits, donuts

Dukat, S.G. · Post by **Dukat, S.G.** » Wed Mar 14, 2012 3:46 pm

All,

I need a tool, like a hole-puncher, that can make various-sized little round bits from styrene sheet, as little as a mm or two wide. Ideally, I would also like something that could punch out small doughnut-like circles.

Am I looking for something like a tap and die set? I'm embarrassed to ask, but I've only truly ventured into scratchbuilding recently.

I am also keen to make tiny styrene spheres (again, as little as a millimeter) and learn how to add rivet detail. I've done an okay job by using the blunt end of a pin vise drill bit, but the results are inconsistent.

One other thing. Does anyone know a good source for clear red and yellow plastic? The sort I'm looking for used to come with the old Transformers toys; you'd take the red plastic and use it to "read" the tech specs of Optimus Prime, Megatron et al. I know some three-ring binders come with clear plastic tabs, but I'm looking for something larger.

Thanks for any input.

Kylwell · Post by **Kylwell** » Wed Mar 14, 2012 3:53 pm

What you want is a micro punch & die set. The only one I can dig up @ the moment is the MicroMark one http://www.micromark.com/micro-punch-set,8603.html

There are a few others out there, none that'll do a donut in a single punch but you can easily do the smaller hole then the larger one.

Ah, I knew there was another: http://umm-usa.com/onlinestore/product_ ... ts_id=1320

kryptosdaddy · Post by **kryptosdaddy** » Wed Mar 14, 2012 4:38 pm

Punch set could be your best investment-

as far as the colored sheets, go to a lighting company- the type that sells band lighting gear and check out the 'cells' colored sheets that change the color of the lights- maybe there you can find something sturdy enough.

Umi_Ryuzuki · Post by **Umi_Ryuzuki** » Wed Mar 14, 2012 5:35 pm

I just sharpen the end of a K&S brass tube and punch the hole or piece I need.
You can sharpen to the inside, or outside edge, then drill a dowel or block of wood
to make a "T" handle. I have a whole series of them I keep in the drawer.

Dukat, S.G. · Post by **Dukat, S.G.** » Fri Mar 16, 2012 3:39 pm

Kylwell wrote:What you want is a micro punch & die set. The only one I can dig up @ the moment is the MicroMark one http://www.micromark.com/micro-punch-set,8603.html

There are a few others out there, none that'll do a donut in a single punch but you can easily do the smaller hole then the larger one.

Ah, I knew there was another: http://umm-usa.com/onlinestore/product_ ... ts_id=1320

Both look very good -- a little more money than I can spend right now (shopping at MicroMark could see me about 10k in debt overnight

), but definitely something to consider for the future.

Dukat, S.G. · Post by **Dukat, S.G.** » Fri Mar 16, 2012 3:40 pm

kryptosdaddy wrote:Punch set could be your best investment-

as far as the colored sheets, go to a lighting company- the type that sells band lighting gear and check out the 'cells' colored sheets that change the color of the lights- maybe there you can find something sturdy enough.

Interesting.

Thank you!

Dukat, S.G. · Post by **Dukat, S.G.** » Fri Mar 16, 2012 3:42 pm

Umi_Ryuzuki wrote:I just sharpen the end of a K&S brass tube and punch the hole or piece I need.
You can sharpen to the inside, or outside edge, then drill a dowel or block of wood
to make a "T" handle. I have a whole series of them I keep in the drawer.

This sounds like the most affordable option for me at the moment -- thanks, Umi.

Another silly question: what do you use to sharpen the inside/outside edge? I tried working over a piece of brass tube with a low-grade sanding stick (probably equivalent to about, oh, 200 grain?) and it couldn't quite cut through mm thick sheet styrene. Of course, I didn't use a dowel to make a t handle with the thing; I was just playing around.

Kylwell · Post by **Kylwell** » Fri Mar 16, 2012 3:44 pm

The I'd try Umi's method. I've had issues with smaller diameters (which is why I got the punch & die set) using a sharpened tube but it works great for larger diameters. For even larger you can get an Olfa circle cutter

Go Flight · Post by **Go Flight** » Fri Mar 16, 2012 10:45 pm

Couldn't you just buy small sized styrene tubes and rods and cut thin sections from them?

Dukat, S.G. · Post by **Dukat, S.G.** » Sat Mar 17, 2012 10:05 am

Go Flight wrote:Couldn't you just buy small sized styrene tubes and rods and cut thin sections from them?

I actually tried that first. Even when I couldn't get tubes small enough, I'd stretch them with a flame 'til I got the diameter necessary.

My main problem with cutting small tubes and rods (or larger ones, for that matter) is that I can never get nice, consistently thick pieces. Even with a fresh #11, I might wind up with three satisfactory pieces if I carefully cut ten total.

ajmadison · Post by **ajmadison** » Sat Mar 17, 2012 10:39 am

Dukat, S.G. wrote:
Go Flight wrote:Couldn't you just buy small sized styrene tubes and rods and cut thin sections from them?
I actually tried that first. Even when I couldn't get tubes small enough, I'd stretch them with a flame 'til I got the diameter necessary.

My main problem with cutting small tubes and rods (or larger ones, for that matter) is that I can never get nice, consistently thick pieces. Even with a fresh #11, I might wind up with three satisfactory pieces if I carefully cut ten total.

The solution to making sections of thin tube the same thickness is to glue them with superglue to a piece of scrap sheet. Then sand them with a sanding block of some form (e.g. wet/dry paper wrapped around a ruler). You can do this by eye if you're patient and check alot. Or you can set down two pieces of brass or aluminum strip on either side, and sand until the block is resting on the metal strips.

You can then 'pop' the donuts off the scrap styrene. A bit of light sanding on the side that was glued and they're ready to go.

You can also make actual "nuts" this way. Take a section of tubing, and slice or sand it into hexagonal, hollow, prisms. Slice off your sections, then sand them to a consistent thickness.

Dukat, S.G. · Post by **Dukat, S.G.** » Sat Mar 17, 2012 5:08 pm

AJ, I appreciate the input.

I stupidly miscommunicated what I meant to say; i.e., I can produce styrene rods and tubes of comparable length, but when it comes to slicing little tiny pieces diagonally, I have problems.

The sharper the blade, the fewer the problems, but it still takes several tries.

Mr. Badwrench · Post by **Mr. Badwrench** » Sat Mar 17, 2012 11:20 pm

Would a miter box help?

Andrew Gorman · Post by **Andrew Gorman** » Sun Mar 18, 2012 12:58 am

For tiny balls for rivets, Brita water filters are chock full of them. Just last week I picked up the Micromark knock off of Northwest Short Line's "The Riveter" and it seems to work very well. There is some information on it and other rivet methods at:
http://15mmvsf.bagofmice.com/vsf/builder_rivets.html
A Waldron punch is a great thing to have as well.

Tankmodeler · Post by **Tankmodeler** » Sun Mar 18, 2012 11:56 am

For rivets, look no further than Grandt Line rivets. Do a search for "Rivets" on this page:

http://www.grandtline.com/product_listing.htm

Great parts. I've used them for years & scratchbuilt riveted AFVs using them.

Paul

Umi_Ryuzuki · Post by **Umi_Ryuzuki** » Sun Mar 18, 2012 1:39 pm

Sharpening brass tubes is done with an exacto knife.
It will dull the blade horribly, but I angle the blade against the
inside of the tube, press and spin the tube, shaving thin bits till
the bevel meets the outside edge of the brass tube.
Once it gets fairly thing, I sand lightly around the outside of the tube
to remove any burrs or flare. They can be pretty sharp.
The smallest I do might be 3/32".

For rivets, I have used super extra thick CA placed using small teflon tube applicator.

Archer makes some rivet decals...
http://www.archertransfers.com/

Tankmodeler · Post by **Tankmodeler** » Sun Mar 18, 2012 3:56 pm

Umi_Ryuzuki wrote:Sharpening brass tubes is done with an exacto knife.

??? Really? Wow, I've done this before, but I use my Dremel & the grinding stones to get the basic shape and then you can fine hone the shape with a knife sharpening stone.

Archer makes some rivet decals...
http://www.archertransfers.com/

And these are _really_ great as well. They don't have as much relief as the Grandt Line rivets, but they are a heck of a lot easier to apply and, when building in smaller scales, they are really effective. In scales larger than 1/48 they are less so.

Paul

Lt. Z0mBe · Post by **Lt. Z0mBe** » Sun Mar 18, 2012 7:52 pm

You might also check for some jewelers' punches on ebay. They're just as good and oftentimes a set is much cheaper than the one sold in the hobby catalogs. I got mine for less than $20.

Kenny

ajmadison · Post by **ajmadison** » Tue Mar 20, 2012 8:56 pm

Mr. Badwrench wrote:Would a miter box help?

A Chopper II made by Northwest Short Line and sold by Micro-mark is the better tool (for this application). You can even set it up, so it can cut consistent length pieces. Albeit, it has limitations, lengths at, or under 1mm are not very consistent.