New lathe help

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Neil

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Well, we got a lathe for my mom's bday (we all wanted one, it was just a question of when), and we have started to try out some nose cones. We made one nosecone that doesent fit any tubing known to man, but thats OK, because it was just our first practice run to see if the lathe works or not. We went to a lumber store where my mom had found basswood before, but they didnt have any. They gave us a big 4X4 of pine for free, though (cant imagine why), so we are making a 3" nosecone out of that. We are to the point where we need to finish the tip off. Last time we tried (the balsa cone), it just flew off halfway across the garage when the tip broke off.

So heres my question: How do you bring the nose cone to a point without it flying off and killing you?

My dad wont let me work on the pine cone on my own, but he says if we get some more balsa, I could give it a try.

We are trying to think of ways to seal the pine. Im thinking coating it in US Composites epoxy might work, but what other (easier) alternatives are there? If we didnt get this chunk of wood for free, we wouldent have used it, but we figured even if it wont be usefull, it will be good practice.

What are your thoughts?


Yea, yea, I know. Ill give you the pics as soon as I finish the cone :p
 

BlueNinja

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Thoughts?

YOU ARE SO LUCKY.

For sealing I would find some other rotating thing (change the drive on the lathe so it is switchable, either gears or pulley.) This would be nice cause you can turn it, then slow it down and coat it.
 

Neil

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I quite agree on the lucky part :D

I think the US Composites will be pretty even if I just hang the cone upside down and coat it. Its pretty thin stuff... Itll run pretty well.
 

BlueNinja

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Long as you put a drip pan underneath :eek:

And don't do it over a picnic table ;)
 

Neil

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har har. :mad:


But, to the more important problem... How do I keep the nose cone from breaking off and sticking itself through my stomache when we get to the tip? :confused:
 

Stymye

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Neil, run the lathe real slow when your ready to cut the tip.
support it with your hand or with a glove on(stay away from the chuck !) you can also stop before it's all the way thru and just saw it off and just hand sand the tip smooth. the key is >slow<
it should ,at worse bobble onto the bed ...not fly across the room!
 

wwattles

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I'm sure Sandman will be providing the definitive answer on this, but here's what I've seen done.

Sand it down to about a toothpick's diameter off the end of the cone, then stop the lathe, and using a razor saw, cut through the remaining wood. Pull the cone off the lathe, and sand down the tip by hand.

Can't really speak to the epoxy part of the question...

WW
 

DJ Delorie

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Having built nosecones on the lathe before, I have some suggestions. First, try the rec.crafts.woodturning newsgroup for general turning help. Second, if you don't need to hollow the nosecone, the base of the nosecone should face the chuck, not the tailstock. Then you can turn, sand, and finish all on the lathe, and cut it off with a parting tool or saw.
If you *do* need to hollow it, the nose points towards the chuck. Leave 1/2" or so connected until the last minute - do your sanding and finishing on the remainder at this point too. To part it off, use the lathe's slowest speed and a sharp skew (not a gouge) short point down. Hold the skew in your right hand/arm, with your left arm reach around the other side and cup your hand around the nosecone to catch it when it falls. Try to leave a little "nub" attached to the cone to avoid tear-out damage, and sand it off later. You can also use the tailstock to support the nosecone during this operation, if you have a cone center for it. Else, stuff paper towels into the hollow and press the tailstock into that.
 

sandman

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Neil,

Mounting the nose cone in the lathe is one of the most challenging parts of turning nose cone.

The larger the nose cone the harder it is.

The best accesories to get for mount nose cones is a #2 Morse Taper drill chuck head (1/2" at least) and the most useful for larger cones is a "bowl faceplate."

Using the drill chuck is pretty simple. Glue a hardwood dowel (PERFECTLY CENTERED!) into the nose cone stock. Be very careful when turning a large nose cone like this. The wood dowel can only take so much strain. You will also find how much "strain" the dowel will take without distorting and causing the cone to be "out of round".

The "bowl plate" is a flat plate that is attached to the wood stock with screws (Use staneless steel screws!) and the whole assembly is threaded onto the headstock.

Both of these methods, drill chuck and bowl plate allows the wood to be turned with one end (the tip) to be free.

Neil, lathe turning is really not something I can teach you here. Go back to the lumber yard and get more wood and practice, practice, practice.

I'm not even going to start to explain the use of lathe turning tools.

I've been doing this (turnings) for over 40 years (I started in high school!). There are just too many techniques that I have learned over the years that I just can't explain in words alone.

After you have a few pieces fly across the room then you will understand why I charge as much as I do for custom work.
 

JStarStar

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How much different is it to use a drill press to turn small cones?
I got a drill press a few weeks ago, I am just trying to figure out a good place to set it up in my workshop.
 

sandman

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I have used a drill press.

As a comparison:

You are usually limited by size. probably nothing much bigger than a BT-70 size...and that's pushing it.

Use of a wood dowel is required. The largest wood dowel you could use is probably 1/2".

The vertical turning position takes some getting used to. Not too bad though.

Lack of an proper adjustable tool rest. You will have to make something.

Inability to use proper "lathe" tools. I suppose you could use them but it would be hard.

A drill press would be fine for all LPR and most MPR sized cones.
 

rabidsheeep

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you said about finishing it with apoxe?

doesn't CA or apoxe or most glues push the grains out of the wood? this is good for making it smooth if your gonna sand it down after, but if you have a nice raw smooth finish then wont this mess it up?
 

jetra2

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CA likely would spread out the grain because it cures real quick when there's a lot of surface area (i.e. a chunk of balsa), but finishing (thin) epoxy shouldn't do anything except provide a beautiful surface for finishing because it cures slllloooooowwwwlllllly (lol, j/k).

Jason
 

Neil

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Wheee!!!!! I just finished the first nosecone that I did 90% on my own!!! I didnt do some of the "more dangerous" parts, because my mom would cut my head off with a butter knife if I even thought about it... My dad had to do that. But here is the picture of my first nosecone! Its great! The tip is pretty blunt, but that doesent really matter to me.. It still looks great!

Its 2" diameter (for a 2" mailing tube), and 10" long (exposed lenth). 1 3/4" long shoulder. The shoulder is a little too small, but thats what they make masking tape for.

We had a lot of ceader 4X4s leftover from an old bunk bed my dad made ages ago. He was a little mad at the people who made the 4X4s when he looked at them more carefully today, because, aparantly, they were "old growth" trees. I think he said he could tell it was so because the grains were so close together... He just couldent believe they would take such good wood and make it into 4X4 posts... Oh well. It makes for a good nosecone!! :D We decided we didnt want to screw up and have the cone fly off and break, so we just got it down to about a quarter inch thick at the tip and cut it off with a saw.

Ok. Whats the catch? What is the fatal flaw in cedar that will make the whole thing blow up in my face? Theres gotta be something wrong with it. There always is :rolleyes: Whats the catch?

Anyways, heres a picture of it!

Im very pleased with myself. Can you tell? :D ;)


oh, and if I dont coat it with anything and just leave it raw, will it be OK? This wood has been sitting in our garage for 3 years, if that makes a difference. Would a regular wood stain be OK, just for aperances sake?

We have quite a pile of this wood in the garage, so we can get a lot of practice. If my mom will let me do it on my own... My dads gone so much of the time, hes only around about every other weekend... And every other weekend is usually a rocket launch... Oh well. Maybe my mom will let me once I do a few more and survive.:kill:
 

sandman

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The only problem with cedar is the cedar oil and the fairly open grain.

That's only a problem is if you want to paint it. Just use a good primer like Kilz.

That's about all.
 

Neil

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Thanks! I cant wait to do another one... I think I might try a transition sometime, just to see if I can do it.

I have to make a bigger cone out of foam soon, too... Several, actually...

My dad made some handy calipers, too. They dont tell you any numbers, but if I adjust them to the diameter of the body tube, I can get the right size anyways.
 
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