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Forum topic by Jerome posted 12-24-2017 01:22 AM 1035 views 0 times favorited 23 replies Add to Favorites Watch
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Jerome

145 posts in 2335 days


12-24-2017 01:22 AM

Topic tags/keywords: lathe excelsior

Hello and thanks for reading!

My current project is currently on hold. After about 20 seconds of rotation, my workpiece came off the large and sustained some damages. I thought that I had everything set properly, but something went wrong.

I notice some vibration in the end as the price was spinning off the facplate , but no vibration upon startup. The workpiece is about 9 pounds. It was running at 1600 rpm. Will someone tell me why the workpeice came off? Do I need longer screws, slower speed, different tailstock, bolt down lathe the table, or just a better lathe? This lathe is 1/2 HP and I do not envision doing items larger that this one.

-- Jerome, Marietta, GA


23 replies so far

View johnstoneb's profile

johnstoneb

3064 posts in 2379 days


#1 posted 12-24-2017 02:42 AM

1. bolt down the lathe
2.Slow down the lathe
That is a lot of weight for a lathe that light.

-- Bruce, Boise, ID

View Jim Jakosh's profile

Jim Jakosh

21757 posts in 3311 days


#2 posted 12-24-2017 02:53 AM

Hi Jerome. The screws certainly look long enough. Is that piece in the last photo what you were turning that flew out?

If it was off balance, 1600 is way too fast, but with it on the face plate and with a tailstock center in it, I don’t see where it would have freedom to come off, but vibration only gets worse with speed..

It looks like a stack of parts glued together. What are you making?
I was taught that when I use a faceplate to always use 8 screws. And when there is an off balance situation, start out slow and speed up only when the part is getting trued up and has no vibration.

I would think you can turn that part between centers to round it up, but start out at 500 or 600.

Cheers, Jim

-- Jim Jakosh.....Practical Wood Products...........Learn something new every day!! Variety is the Spice of Life!!

View bondogaposis's profile

bondogaposis

5098 posts in 2557 days


#3 posted 12-24-2017 03:47 AM

Yes, you absolutely have to bolt down the lathe.

-- Bondo Gaposis

View Woodknack's profile

Woodknack

12431 posts in 2586 days


#4 posted 12-24-2017 04:06 AM

When using a faceplate plus a tailstock you need to make sure that the live center is in the exact center of rotation.

-- Rick M, http://thewoodknack.blogspot.com/

View John Smith's profile

John Smith

1491 posts in 369 days


#5 posted 12-24-2017 04:15 AM

I may be wrong, but from what I see – - – -
the tail center was not inserted deep enough into the soft wood and it walked out when the dance started.
you can see where it came out and walked right off the edge of the stock being turned.

my personal choice of center for a large job like this would be with a large cup –
tapped in tight with a hammer prior to mounting in the lathe. but that’s just me.

.

-- I started out with nothing in life ~ and still have most of it left.

View Nubsnstubs's profile

Nubsnstubs

1422 posts in 1936 days


#6 posted 12-24-2017 04:59 AM

I’ve made those marks before. It was because the tailstock wasn’t locked down and lost the tension between centers. Use larger diameter screws, get the proper tension between centers, and make sure the tailstock and the quill lock are tight. Start slow, and speed up when it’s balanced. Good luck…......... Jerry (in Tucson)

-- Jerry (in Tucson) www.woodturnerstools.com

View alittleoff's profile

alittleoff

541 posts in 1482 days


#7 posted 12-24-2017 07:19 AM

I’ve never turned anything or even been around a lathe that was running, but it looks to me that the tailstock was barely in the end or the wood. I’d have it in alot more than it was. But like I said I’m just guessing.
Gerald

View Bill7255's profile

Bill7255

428 posts in 2491 days


#8 posted 12-24-2017 10:21 AM



I may be wrong, but from what I see – - – -
the tail center was not inserted deep enough into the soft wood and it walked out when the dance started.
you can see where it came out and walked right off the edge of the stock being turned.

my personal choice of center for a large job like this would be with a large cup –
tapped in tight with a hammer prior to mounting in the lathe. but that s just me.

Agree 100%
.

- John Smith


-- Bill R

View stefang's profile

stefang

16144 posts in 3540 days


#9 posted 12-24-2017 10:53 AM

Hi Jerome, it would have been better to turn that piece using a headstock drive center instead of a faceplate. This will allow the piece to rotate off-balance between two small points without tearing anything out. The suggestions to anchor your lathe should also help.

Merry Christmas!

-- Mike, an American living in Norway.

View mahdee's profile

mahdee

4025 posts in 1973 days


#10 posted 12-24-2017 02:44 PM

+++ John Smith

-- earthartandfoods.com

View dhazelton's profile

dhazelton

2798 posts in 2503 days


#11 posted 12-24-2017 03:04 PM

More mass on your lathe bench (sandbags or whatever), lower speed and a tail stock with a spur as suggested.

View Jerome's profile

Jerome

145 posts in 2335 days


#12 posted 12-24-2017 06:54 PM

@John Smith. I purchased the live center tail stock today from Woodcraft. Thanks for the tip! I plan on switching to a spur center and hammer both ends in pretty good to keep it secure, set it at 600 rpm, and bolt it down.

-- Jerome, Marietta, GA

View John Smith's profile

John Smith

1491 posts in 369 days


#13 posted 12-24-2017 08:50 PM

I work with mostly hardwoods, which is a pain to get the point to go in very deep.
I drill a hole with a 3/16” bit maybe 3/8” deep and hammer the centers in with a hammer to get a good bite.
then chuck it up in the lathe. my most frequent problems is that I forget to tighten down the tail stock.
over the past year, I have treated myself to several centers and a 4” x 3 jaw self adjusting chuck.
I think the chuck probably gets the most use, as I turn a lot of metal head mallets.
I can vouch for the higher priced live centers being the less problematic.

Happy Turnings !!

-- I started out with nothing in life ~ and still have most of it left.

View John Smith's profile

John Smith

1491 posts in 369 days


#14 posted 12-24-2017 09:07 PM

I am on my second HF 12”x36” lathe. the first one I had for maybe 20 years
and was only used to turn circular disks for round signs – some were 5 ft in diameter.
never turned a round piece of wood on it. only High Density Urethane (HDU) sign foam.
sold it 10 years ago and took a 5 year break from my hobbies to renovate my homestead.

the signs were either for a master pattern to make aluminum reproductions with or finished one of a kind.
first I spin just the round disk with any round bands in it as one piece.
then using a paper pattern, I hand cut the thin plastic foam elements and glue that to the disks.
then, small plastic letters are glued where needed – wala – a nice round sign !!!
you can do a lot of really cool stuff with a wood lathe that has the headstock that can turn sideways !!
but, alas, the 21st Century has caught up with me with the new fangled CNC routers that put craftsmen
like me out of business. oh well, it is time to retire anyway !! LOL

.

-- I started out with nothing in life ~ and still have most of it left.

View Jerome's profile

Jerome

145 posts in 2335 days


#15 posted 12-25-2017 03:46 AM

@ John. Will be so kind so post,a picture of the Chuck you speak of? Merry Christmas!

-- Jerome, Marietta, GA

showing 1 through 15 of 23 replies

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