the one billionth lathe question...

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rabidsheeep

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well, i somehow have huge masses of money lying around for some unknown reason, and i was thinking about this for awhile so ill go ahead and ask (again)

this time i think ive narrowed it down to something that will suit me fine:

https://www.grizzly.com/products/item.cfm?itemnumber=H2669

now, i doubt ill ever make anything over 2 1/2 inches (first im starting REALL small)

im just wondering if this will turn (just balsa) well enough, if it is high enough from the base etc., or if anyone has worked with one?

i have a 3500 rpm max fully variable speed drill (not battery powered)... would this be alright?

thanks

sheeepy
 

eugenefl

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Sandman, I have a drill press and haven't had any luck turning any balsa parts on it. There is no "spinner" end side to keep the piece stabilized. Some pieces have "wobbled" their way out of the chuck. The jaws of the chuck don't seem to hang onto wood dowels very long. I imagine I could make something to go on the table end to hold the other side of the piece, but it hasn't worked out otherwise. Also, it just seems like cutting into wood on a horizontal plane is easier than vertically.
 

sandman

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The "tailstock' can be made from a scrap of wood with a short wood dowel tapered to a point and clamped onto the drill press table.

eugene,

The problem you are running into is caused my the uneveness of the balsa density. The balsa is harder on oneside than the other.

This get exaggerated when you try to sand the part by wraping the sandpaper half way around the part...it will get egg shaped!

I have found a few ways around this. The best way is to make a tool rest for the drill press and make some sandingblocks out of 40 grit and 80 sandpaper.

The skill in making nose cones comes from listening to the sound of the sandpaper cutting the wood.

It also helps to "back light" the work and you can actually see it if it's out of round. By carefully "kissing the wood you can hear it cut and you can see when it is perfectly round.
 

rabidsheeep

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can you just explain alittle better on how to spin the nosecones on the drill press?

that would be awesome especially for cr's

and another thing... i heard somewhere here that for tools, instead of using chizels (sp?) on balsa to use those 30 cent nail files (or just sandpaper?) because the chizels tear the soft wood apart (that and files are more appealing cause their cheaper

thanks again

--sheeepmiester
 

sandman

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I use the cheap emery boards from the dollar store (two packages for a dollar).

Basically yes don't use chisels or normal lathe tools. (I do but that's another story)

Make your own course emery boards by gluing the 40grit and 80 grit sandpaper to everyside of a block of wood.

Just cover the block with sandpaper.

I use sandpaper from an auto paint supply store and just glue it on with contact cement.

OK...here goes!

Step #1
Drill a hole into the block of wood and glue in the biggest dowel that wil fit the drill chuck (I like that drill press I showed you 'cause it has a 1/2" chuck!)BTW I have THAT drill press and it works fine.

Step #2
With a razor knife cut the corners off of the wood. Make it as round as you can with a knife. (I use a two handled razor sharp draw knife!)

Step #3
Chuck it into the drill press as tight as you can without crushing the wood dowel...you will regret doing that!

Step #4
Start the drill and lightly touch the wood with the 40 grit sanding block that you made...lightly!

Step #5
Turn off the motor and look where the 40 grit hit the wood...shave this off with the razor knife (this is to eliminate any unevenes of of center when you glued in the dowel.

Step #6
Use a tool rest and slowly kiss the wood with the 40 grit until you can hear that it is nice and round...you will no longer hear the heesh, heesh sound of the sanding block hitting just the corners or one side. It should be a nice even hissssss.
REMEMBER! not too much preassure.
Too much pressure will distort the wood dowel and get the piece to wobble or worse yet even come loose from the chuck!

Step #7
When you are fairly close to the shape you want switch to the 80 grit to get the big sanding lines out then switch to the emery boards.

I do my final shaping and sizing with 220 grit leaving just a little extra.

Step #8
Finish the cone off with 320 or 400grit...not too much pressure or it'll go out of round.

Hmm...maybe it would be easier if you just came over to my place and I'll show you how...it might take a few days.:rolleyes:
 

rabidsheeep

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ok, so the actual piece of wood is suspended over the table of the drill press? meaning its not held at two ends, just the one by the dowel?
 

sandman

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Yes, the wood dowel is all that holds the wood. That is one of the benifits of that particular drill press, you can use up to a 1/2" dowel glued into the balsa.

This does limit your size to a BT-80 nose cone and that's a stretch at that.

There is just so much mass even with balsa that if it is even a little imballanced it will wobble like crazy.

Besides...a drill press can drill a really nice square hole into the balsa.

If you want a lathe...buy a lathe.

This is the primary lathe that I use and I just LOVE it!

https://www.woodcraft.com/Woodcraft...alse&mscssid=650CEF1065AA49C4BE5F391918624DA8
 

rabidsheeep

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i think ill go for the drill press... gonna take lotsa practice but hopefully ill make something vaugly resembling a nosecone :p

thanks sane, eugenefl, and stymye

now the hard part... getting the credit card from mom.
 

sandman

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I can't recall ANYONE ever calling me "sane" or ever having a reason to.

Must have been a misprint!;)
 

Stymye

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one key tip I learned from Sandman,
make sure to use hardwood for the dowel the harder the better
soft wood just wont hold tight in the chuck, they will just wobble or fly out.
ohh....and don't use the wifes(or moms) wooded spoon handles.
 

rabidsheeep

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:D

lets just say its as good as ordered

i tried googling but i couldn't find much on how to cut crs (my idea was cutting a rough circle with my dremmel or jig saw, then having a bolt down the center to spin it to an even circle, but what for cluster mounts?)

is there a bit or something that helps with this?

*runs off happy cause power tools are fun fun*
 

sandman

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I use that technique to make centering rings and a few more using my lathe.

For cluster rings I simply have a few cluster tube "sets" glued up and use then to trace where the holes will go.

Then I use these:

https://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=1903

to drill out the motor holes.

A 3/4" is a tiny bit sloppy for a BT-20 (18mm) and a 1" is really close for a BT-50 (24mm)

That's a nice cheap set with most of the sizes you will need.

Perfect for your drill press!

I have a much bigger set!:rolleyes:
 

extremevelocity

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Hi guys this was discussed here on the forum a long time ago:D
What you do is use the bearing from an old hard drive to stabilize the piece your'e working on.

It should be fairly straight to mount it to the table for your drill press.
I 'm going to do the same thing myself as I got my own drill press.
Good luck and let us know how it works out for you.
mikey
 

stevem

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hard drive motor tailstock

this works real well for turning large cones and could easily be adapted for drill press turning.

I have turned a 3x3x14" balsa block on this with no problems.
 

Micromeister

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or just a machine screw filed to a point;) or a machine screw mounted in a dowel to set in a hole works like semi live center. If nothing else it's a fun winter project by itself:D
 
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