Chatter on 10 x 22 Lathe

[ozzie46]

I'm getting a lot of chatter on my new Grizzly 10 x 22.

It see ms to be a souped up 9 x 20. Could it be the way the compound is held on by 2 bolts.? Is that why they do a four bolt mod on the 9x 20s ? The 9 x 20 have t slots but mine doesn't.

Any ideas?


I was turning some hot rolled steel at about 150 rpm taking about 20 to 30 thou.
cuts. Dia was 1 7/8.



Ron

 

[Philjoe5]

Ozzie,
I have a 10x22 and you shouldn't be seeing chatter with the conditions you're describing if you have a sharp toolbit. What is your feed rate? Do a slow hand feed and if you get good results, slow down the feed. I'd also check that the gibs are snug. I'd also remove the compound and make sure a bunch of swarf didn't find its way under there.

I also have a 9x20 and did the 4 bolt compound clamp mod with great results. But it really isn't necessary on the 10x22.

Cheers,
Phil

 

[ozzie46]

Is 20 to 30 thou to light a cut?


Phil, Gibs are tight. I hand fed slow and no difference. This was the first turning with this lathe, it is new and I cleaned it and adjusted everything before using it.

I wonder if the steel could be the problem as I did test cuts to check accuracy of the lathe on a mirror finish bar from a printer and it cut like butter.


Ron

 

[Philjoe5]

Ron,
From my experience 20 - 30 thou (infeed) should be fine on a piece of good steel. I ran into a lot of problems cutting steel when I bought my first (9x20) lathe a few years ago. I had bought some "CRS 1018" steel at a salvage company. I tried for months cutting that stuff - using cutting oil, playing with speeds, feed rates, carbide, HSS but it never gave a good finish. Over time I moved on and finally got some 1144 alloy free machining steel. All I can say is, when using a new lathe, mill or any metal cutting machine for the first time use a good piece of steel to check it out. If you can't get a good finish on it, then start looking at the machine and its various adjustments.

Good luck in chasing this thing down.

Cheers,
Phil

 

[ozzie46]

Thanks Phil,

The steel I was turning took the tip right off of my HSS 5/16 tool, switched to a 5/16 carbide tool and it did better. Gave an very nice finish.

I also shortened up the tool overhang. I didn't think it was very much but I guess I was wrong. Sure puts the 4 way tool post close to the work.


Wonder if the 5/16 tool bits are to small for this lathe?

Ron

 

[Philjoe5]

Ron,
I've been using the 5/16" and 3/8" tooling with good results on the 10x22. I also recently setup one of my toolholders for 1/4" but just haven't tried it yet. I have a QCTP which I installed when I first bought the lathe so I haven't had much experience with the stock holder.

Cheers,
Phil

 

[ozzie46]

Thanks Phil, thats good to know. I am building a QCTP for this lathe.

Will see how it comes out.


Ron

 

[joeby]

I didn't see any mention of the length of your part. How much are you actually holding in the chuck? How much overhang?

I try to use the three jaw only when I can work close to the chuck, if the part overhang is more than 2 or 3 times the diameter I will use the four jaw or turn between centers.

Kevin

 

[hammers-n-nails]

every time that i can remember ive had chattering issues the cause was a dull tool or not enough relief angle,rake angle could have something to do with it also, but i doubt it. and sometimes the stock is just too long as was mentioned earlier. im not an expert but that has been my experiance. thats my 2 cents.

 

[ozzie46]

Joeby, Hammer, Thanks for the reply.

I was using a live center in the tail stock. The part was about 3 in. long and 1.750 dai.

It knocked the edge right off my HSS tool bit so I went to carbide and it did better.

Ron

 

[doc1955]

I am just finishing up a QCTP I didn't like the on that came with my lathe. I did post some drawings that I have pulled off site. I need to apologize as the drawings I posted were my very first preliminary drawings and I changed a lot of things. I am looking for my PDF files for it but haven't found them. So I need to redraw as they were all based on hand drawn sketches. I'll try and get the right drawings posted I have built about half a dozen of these QCTP for friends. I'll try and get some photos of the one I'm finishing up on.

Thanks Phil, thats good to know. I am building a QCTP for this lathe.

Will see how it comes out.


Ron

 

[ozzie46]

Doc, I'll be looking for them. I'm using some I got off of a Japanese guys site. Changing them some. Not to much.

Be interested in seeing yours.

Ron

 

[doc1955]

Well I finished all that's left is to give it a good deburing and get a knob.
Never mind the cap screw I'm using for a handle it will be replaced by a proper knob.
Now I can use all my old holders I used in the tooling shop that I still have.

 

[Cliff]

Hey Ron how is your lathe running good I hope. I have a set of prints like the ones doc1955 was talking about I got them from a post on here a while back I can send you a copy if you want just let me know. Cliff

 

[pete]

Ozzie,
One more thing that has not been mentioned, Try increasing your feed per rev. I ran into this exact same problem with a older Emco compact 5 lathe turning stainless at .003 feed per rev. The chatter was very bad and I replaced the headstock bearings. After that, Same material, Same feed, And had the exact same chatter, After increasing the feed to .006 per rev. the chatter disappeard. Same thing works on a drill press, Anytime I've had chatter with larger drill bits then lean into the handles and make the bit work.

Pete

 

[ozzie46]

Good to know Pete.

Cliff, thanks but I think I have them already. The pics sure look like some plans I have.


Here is the one I'm sort of copying. Made a couple of svery minor changes.

http://homepage3.nifty.com/amigos/qctp/qctp-e.htm

Wiil post some pics soon.

Ron

ps. Lathe is running great now that I cleaned it and changed spindle bearings.

 

[doc1955]

Here is a pdf of the corrected drawings and not the preliminary that I didn't realize I posted.
This pdf is the drawings from the holder I just finished.
I'm happy with the new QC I have now. I had all the tool holders I made years ago and that have a lot of miles on them so I didn't need to make them. I may draw up the parting blade holder that is the only one that is a little different from the others.
I like this style holder better than the one that came with my lathe never did like the holder with the dovetail male end on the tool post and the female end on the holder.
I used a holder very similar to this one on a precession tool room Harding lathe that's when I made my own tool holders to fit it.

View attachment QCTP6087_-_.pdf

 

[ozzie46]

Thanks Doc, Nice drawings. put in TO Do file.

May I ask why you feel female dovetails on main block are better and is this size suitable for a 7X?

Ron

 

[doc1955]

I don't know why for sure other than the shop experiance I've had I prefer them.
For a 7 inch lathe I'm not sure you may have to check center height and when you make your cutter holders adjust acordingly. What I did to get the center height of the holders where I wanted I just clamped holder in tool post and put a center drill in chuck and drilled a center hole useing headstock. That way I knew the height would be ok.
My guess is that if you move the slot center down a little in the holder it would worh out great for your lathe.

 

[ozzie46]

Thanks Doc.

Ron