grizzly gunsmith lathe tail stock won't lock tight.
Re: grizzly gunsmith lathe tail stock won't lock tight.
Sure it is excessive. W the .. you would bend the new plate. Doesn't that lathe have an eccentric lever? It is all adjustable.
Re: grizzly gunsmith lathe tail stock won't lock tight.
Page 35 Harold. https://cdn0.grizzly.com/manuals/g4003g_m.pdf
Same page in this manual. https://cdn0.grizzly.com/manuals/g0750g_m.pdf
Page 33 for the bigger Gunsmith lathe. https://cdn0.grizzly.com/manuals/g0509g_m.pdf
Pete
Same page in this manual. https://cdn0.grizzly.com/manuals/g0750g_m.pdf
Page 33 for the bigger Gunsmith lathe. https://cdn0.grizzly.com/manuals/g0509g_m.pdf
Pete
Re: grizzly gunsmith lathe tail stock won't lock tight.
Harold, I do not know what numbers are in conflict, but we have done more investigation, and it turns out that conjecture is now moot, we found the smoking gun. We put a little blue on the bottom of the tailstock, on both the Vee side and the flat side, and slid it the length of ways, leaning as hard as I can, surely over 200 lbs holding it down. We had cleaned the ways with acetone, and they were clean and dry. There was blue removed from the bottom in less than 1% of the area of of the bottom surfaces of the tailstock, on both the flat and the Vee side. We completed this test a few times, a few different ways, and indeed this is the problem. It will be interesting to see how Grizzly responds to this. Have a look at the photo below, and you will see that the ways touch almost no where, but the touch close enough to the corners that it will not rock.
Re: grizzly gunsmith lathe tail stock won't lock tight.
The problem was in my head, not your numbers. Sorry 'bout that. For some reason, I had not considered your mention of having torqued to 130 pound ft., so I was confused on that number. I stand corrected!
Hmmmm. Makes me wonder if, maybe, they haven't done that on purpose (not a good idea in my mind). I was shocked to read about the tailstock being drawn down by .006" when the lock was torqued, which would not be possible under normal circumstances. The less than flat base may be why, as wear on a tailstock is generally such that as it wears, it also starts sagging downward at the quill end. Can't help but wonder if they've done that to limit the sag, but it sure as hell accelerates wear. Best to have full bearing, so when the tailstock is restrained it doesn't lose center height.but the touch close enough to the corners that it will not rock.
Mean time, has there been any effort to ascertain if the quill is higher than the spindle? If so, how much? It is common practice for the quill to be somewhat higher, so the lathe wears in instead of out.
H
Wise people talk because they have something to say. Fools talk because they have to say something.
Re: grizzly gunsmith lathe tail stock won't lock tight.
Harold: While I am not a machinist, I am a quality control guy. Mostly in welding but also in structural manufacture and boilers. I would bet money it is junk, and missed a step in the factory. It was sold to a guy who is a beginning hobby machinist, who did not notice it, as he had basically never worked on a lathe, it is only because he thought you should never take deep cuts or experiment to find out how deep you can cut that he did not have a piece come out off the live center. He was not yet interested in optimum feeds and speeds and depths of cut. God knows how much force 130 ft lbs put on the locking cam as it got to the apex of its stroke. We had it apart, the cam was circular, and we had it adjusted so that it was a few thousandths of an inch from being over the top at 130 ft lbs. I was waiting for something to explode. I highly doubt the casting or forging they used as the cam follower in the tail stock was as strong as the stud I made from the mining truck wheel stud that transferred the stress to the anchor plate, and we made the plate out of 1" 70 ksi structural plate, the length of the tailstock minus half an inch, so there was no way that was going to fail. With the 40 ft lbs they recommend you could wind out the quill with only the slightest torque, and there was no sensation of it coming tight. All Barry has done on this lathe is make a few chips, with .010 cuts per side as his deepest cuts. he has carbide tooling for it, and I was over for the first time, and I wanted to make some chips that were hot enough to change color, just to show him it was ok, It was me who discovered it would not lock up. He has had it a few days over a year, and it is off warranty, I hope grizzly does not feed him to the crows... This is a 14x40 gunsmith lathe.. it should have some integrity.
My Indian lathe has a 5/8" coarse thread bolt locking the tailstock, and you have to put 60 or so ft lbs on it.. I have never really checked, I cut the open end off a combination wrench, and just give it a good tug.. but you can push your work into the chuck if the chuck is not properly tight, and I always machine a shoulder if I can to keep the force of the center added to the cutting forces from pushing the work in. this machine will not lock tight enough to do that. I am going on and on, as I sometimes do, but it is sad to see a machine that should be a pleasure be junk.
My Indian lathe has a 5/8" coarse thread bolt locking the tailstock, and you have to put 60 or so ft lbs on it.. I have never really checked, I cut the open end off a combination wrench, and just give it a good tug.. but you can push your work into the chuck if the chuck is not properly tight, and I always machine a shoulder if I can to keep the force of the center added to the cutting forces from pushing the work in. this machine will not lock tight enough to do that. I am going on and on, as I sometimes do, but it is sad to see a machine that should be a pleasure be junk.
Re: grizzly gunsmith lathe tail stock won't lock tight.
Unfortunate to hear this about your Grizzly 14-40 lathe.
I have their model G0709 Gunsmith lathe and do not have any of the tailstock issues your have noted.
It has served me well and done everything asked of it, so far, while maintaining good alignment.
I do hope Grizzly provides the expected good customer service for you.
RussN
I have their model G0709 Gunsmith lathe and do not have any of the tailstock issues your have noted.
It has served me well and done everything asked of it, so far, while maintaining good alignment.
I do hope Grizzly provides the expected good customer service for you.
RussN
Re: grizzly gunsmith lathe tail stock won't lock tight.
Yes Russ, it is surprising, I have not heard anything bad about them, and they are kind of the pride of the fleet at Grizzly. I hope they will look after my friend. I have not heard of a serious complaint about any of their products, it will be interesting to see what they do.NP317 wrote: ↑Mon Aug 24, 2020 10:13 am Unfortunate to hear this about your Grizzly 14-40 lathe.
I have their model G0709 Gunsmith lathe and do not have any of the tailstock issues your have noted.
It has served me well and done everything asked of it, so far, while maintaining good alignment.
I do hope Grizzly provides the expected good customer service for you.
RussN
Re: grizzly gunsmith lathe tail stock won't lock tight.
Grizzly said they will send him a new tail stock, no questions asked.
Re: grizzly gunsmith lathe tail stock won't lock tight.
Amazing! Especially in today's atmosphere.
I had a similar thing happen, although many years ago, and to do with speakers for my stereo system.
I had purchased, new, a set of JBL Olympus speakers, their model C50, equipped with their S8R option, and had used them for nine years. The grill on these speakers is easily removed, and I'd do that often to observe the woofer (15") as it did its thing. In doing so, I noticed there was a crack developing at the outer edge of the cone, where a narrow layer of foam is used to attach the cone to the speaker frame.
A phone call placed to JBL resulted in their asking me to ship the speakers to them, so they could be repaired. While I had to pay to ship them, they were repaired and returned to me free of charge. They were out of warranty, needless to say.
Sadly, that division of JBL is no more. They stopped making their high end speaker systems years ago.
H
Wise people talk because they have something to say. Fools talk because they have to say something.
Re: grizzly gunsmith lathe tail stock won't lock tight.
Delighted to hear of Grizzly's response.
Responsible customer service.
RussN
Responsible customer service.
RussN
Re: grizzly gunsmith lathe tail stock won't lock tight.
He told the Grizzly customer service people that the lathe was not safe because of this problem.. This is what secured the new tailstock.
Re: grizzly gunsmith lathe tail stock won't lock tight.
Wow, $6250 U.S, add in money exchange, gst, pst works out pretty damn close to $9k in Canuck bucks. At least there manning up and doing the right thing. But I certainly would have expected any lathe in that price range and it's supposed extra price for that "gunsmithing status" to have a whole lot better designed and machined bottom locking plate and the tail stocks way's to have at least 50% or more bearing surface. Grizzly might be paying the shipping to get one to your friend. But fairly safe to assume the manufacturer will be eating the costs for the replacement. Did Grizzly say if there sending just a new tail stock casting or a complete ready to go tail stock and how long it's going to take?
Either way, if it were me once I had the replacement fully operational I'd mike the tail stocks quill and then machine a short piece of bar stock in the chuck as close to that dimension as you can. Run the carriage up to the head stock, then move the tail stock up, lock it down to the bed and extend the quill until it touches your test piece. Adjust the tail stock off set in a horizontal plane until it's aligned true to the test piece. Then mike across both the test piece and the end of the quill in a vertical plane and that will give you the new tail stocks alignment to the head stocks vertical C/L height. It should be correct if the manufacturer has rigid + - tolerances they follow for sizes and it's C/L elevation. So if it is correctly made I'd expect it being maybe .002" - .003" high above that test piece. That's normal for even top of the line lathes when new. But if they sent your friends lathe out the door like your pictures show then I sure wouldn't trust anything unless I verified it first. I'd also indicate the tail stocks extended quill with a magnetic base on the cross slide. Run the indicator tip the full length on the top of the quill using the carriage, and then do the same horizontally along the front side of the quill. Any deviation should be well under .001" and I'd be expecting and wanting low 10ths. But your friends test certificate the lathe came with should also show what those factory's allowable test numbers are and what it's supposed to meet before it's shipped.
Either way, if it were me once I had the replacement fully operational I'd mike the tail stocks quill and then machine a short piece of bar stock in the chuck as close to that dimension as you can. Run the carriage up to the head stock, then move the tail stock up, lock it down to the bed and extend the quill until it touches your test piece. Adjust the tail stock off set in a horizontal plane until it's aligned true to the test piece. Then mike across both the test piece and the end of the quill in a vertical plane and that will give you the new tail stocks alignment to the head stocks vertical C/L height. It should be correct if the manufacturer has rigid + - tolerances they follow for sizes and it's C/L elevation. So if it is correctly made I'd expect it being maybe .002" - .003" high above that test piece. That's normal for even top of the line lathes when new. But if they sent your friends lathe out the door like your pictures show then I sure wouldn't trust anything unless I verified it first. I'd also indicate the tail stocks extended quill with a magnetic base on the cross slide. Run the indicator tip the full length on the top of the quill using the carriage, and then do the same horizontally along the front side of the quill. Any deviation should be well under .001" and I'd be expecting and wanting low 10ths. But your friends test certificate the lathe came with should also show what those factory's allowable test numbers are and what it's supposed to meet before it's shipped.