Disappointing T-slot quality

[flick]

My 1100 arrived yesterday, and, having taken the time for a quick initial inspection, I've stumbled upon my first "eyebrow raiser".

My expectations were high, given that Tormach publicizes their QC program with inspectors onsite at the Chinese manufacturing facility, and that they are selling a mature product with an exuberant user base. Even so, I knew I was going to have to live with some compromises in fit and finish, but this one really irks me: the rearmost T-slot has an upwards slope (in depth) of around 1/8", in the last 6-7 inches of the rightmost portion of it's length.

Seeing this defect makes me wonder what other cockroaches might crawl out of the corners as I shine my flashlight around, and it has really taken the joy out of this purchase for me.

[mactec54]

Hi flick
I would contact your seller for a replacement table as they should not have even shipped it like that they should also fit the replacement parts that are needed as well or ship you a new machine

[philbur]

Does the Tee nut jam.

Phil

Originally Posted by flick the rearmost T-slot has an upwards slope (in depth) of around 1/8", in the last 6-7 inches of the rightmost portion of it's length.

[flick]

Philbur: No, the profile of the T-slot is constant. As the depth decreases, the material left between t-nut and table surface thins.

mactec54: I (mostly) agree. It's understood that when you buy a PCNC that there are no factory technicians to come and refit parts. I want to check out the rest of the machine before I contact Tormach to determine how much of the machine I'll be exchanging. I hope I won't have to return the entire thing for exchange. The crate was pretty beaten up on the way here so I just turfed it, and I wouldn't like to build another one. I hope it will turn out the table is the only problem.

[jrwdlw]

Flick,

That's scary. I'm considering purchasing a CNC mill, and Tormach was the primary contender. IH is my other choice, but the price is a little higher. Now, I'm not so sure about the Tormach. Maybe I'll just suck up the extra cost and go with IH.

Quality control issues really tick me off, as it's something that is easily addressed with just a small amount of effort by the vendor/manufacturer. I understand how parts can fail in use, but when you ship out defects from the git-go, that's just sloppy business.

[Ken_Shea]

Flick,
Not a happy find but in reality, what difference will it really make?

I would not expect that Tormach is going to scrap a table just because of a machining error in an area that makes no difference with regards to machining results and in an area that you will likely never use.

Maybe I am reading the problem wrong.

Ken

[philbur]

I think the risk is that you pull the Tee-nut out due to insufficient strength because of the thinner table web. It depends on whether the web on this section is thinner than it should be or if the web on the rest of the slot is thicker than it needs to be. A simple check is to see if the top of a Tee-nut comes above the table in the suspect area. If it does then you can claim you have a problem. The dimensional tolerance on these slots might be quite large so it could be within spec.

It is unfortunate but always a risk with a low cost machine. If there is truely a fault then the real test will be how Tormach handle it. I'm sure you will be satisfied with the final out-come.

Phil

PS: I guess everybody has just rushed out to check their Tee slot depths.

Originally Posted by Ken_Shea Flick, Not a happy find but in reality, what difference will it really make? I would not expect that Tormach is going to scrap a table just because of a machining error in an area that makes no difference with regards to machining results and in an area that you will likely never use. Maybe I am reading the problem wrong. Ken

[philbur]

I think the bottom of the slot is "as cast" which means 1/8" is quite reasonable. So if this is your issue I think you are being over optimistic.

The area that needs checking is the underside of the Tee slot web, where the Tee-nut pulls up against. This should be machined and be parallel with the table surface. As I said previously run a Tee nut along the length with it pulled up against the underside of the web. As long a there are no major discrepancies and the nut never comes above the table surface then every thing is as it should be.

Just some personal thoughts
Phil

[zephyr9900]

Originally Posted by philbur As I said previously run a Tee nut along the length with it pulled up against the underside of the web.

I did exactly that when I received my mill in fall 2006, Phil. There was a discussion early on about how only the center slot on early machines was ground, and the front and back "secondary" slots were only machined. Tormach upgraded the table slots sometime before my machine was made and all three slots are good (serial #128).

Ironically though, I did need to clean up the corners of all my t-nuts (nice TECO brand too) with a fine stone before they would slide cleanly in the slots.

Randy

[flick]

Originally Posted by Ken_Shea Flick, Not a happy find but in reality, what difference will it really make? I would not expect that Tormach is going to scrap a table just because of a machining error in an area that makes no difference with regards to machining results and in an area that you will likely never use. Maybe I am reading the problem wrong. Ken

Well Ken, you've got a point, but the other side of the coin is that once you start making those kinds of compromises in quality, it can become a "slippery slope" type of situation. Sure I can live with it, and it will probably never affect the performance of the machine or quality of my work. I just don't think I should really have to. The best companies on earth (like the one that made my car) have a philosophy of uncompromising quality and continuous improvement, which would not accept this sort of defect.

In any case, I've had a little time to simmer down, and as long as everything else is satisfactory I probably won't even directly contact Tormach about this. It's the kind of problem that's big enough to chap my ass, but too small to actually invest my time in right now. Which is why it's such a disappointment.

In 6 months if I really haven't been able to "let it go", and I have a slow weekend, I may repair it myself, if only to fulfill my own (slightly neurotic) need for consistency. Thinking about filling with some kind of epoxy or composite and remachining. Maybe take a skim off the bottom of all 3, because after another look I've found that the finish in the bottom of the center slot (right near the middle, where it will be used) is a little bit stepped as well.

At the end of the day, shaking my fist in the air and expressing myself in this forum is probably the best I can do. Hopefully, comments from concerned potential customers, as seen above, will reach the company and drive improvements in QC. If not, the competition will have a field day, because this is a competitive market that's picky about quality.

[flick]

Originally Posted by philbur I think the bottom of the slot is "as cast" which means 1/8" is quite reasonable. So if this is your issue I think you are being over optimistic. The area that needs checking is the underside of the Tee slot web, where the Tee-nut pulls up against. This should be machined and be parallel with the table surface. As I said previously run a Tee nut along the length with it pulled up against the underside of the web. As long a there are no major discrepancies and the nut never comes above the table surface then every thing is as it should be. Just some personal thoughts Phil

The bottom of my slots are machined.

[philbur]

Flick, in post #1 you say "the rearmost T-slot has an upwards slope (in depth)"

In post #4 you say "the profile of the T-slot is constant. As the depth decreases, the material left between t-nut and table surface thins."

In post #10 you say "Thinking about filling with some kind of epoxy or composite and remachining. Maybe take a skim off the bottom of all 3, because after another look I've found that the finish in the bottom of the center slot (right near the middle, where it will be used) is a little bit stepped as well."

So is the depth of the slot you are not happy with or is the variable thickness of the Tee slot web over it's length. If you are going to make such strong accusations you need to be very clear as to the problem you perceive.

Phil

PS: You seem to mistakenly think that the finish on the bottom of the slot is in some way important for it's use.

Originally Posted by flick Well Ken, you've got a point, but the other side of the coin is that once you start making those kinds of compromises in quality, it can become a "slippery slope" type of situation. Sure I can live with it, and it will probably never affect the performance of the machine or quality of my work. I just don't think I should really have to. The best companies on earth (like the one that made my car) have a philosophy of uncompromising quality and continuous improvement, which would not accept this sort of defect. In any case, I've had a little time to simmer down, and as long as everything else is satisfactory I probably won't even directly contact Tormach about this. It's the kind of problem that's big enough to chap my ass, but too small to actually invest my time in right now. Which is why it's such a disappointment. In 6 months if I really haven't been able to "let it go", and I have a slow weekend, I may repair it myself, if only to fulfill my own (slightly neurotic) need for consistency. Thinking about filling with some kind of epoxy or composite and remachining. Maybe take a skim off the bottom of all 3, because after another look I've found that the finish in the bottom of the center slot (right near the middle, where it will be used) is a little bit stepped as well. At the end of the day, shaking my fist in the air and expressing myself in this forum is probably the best I can do. Hopefully, comments from concerned potential customers, as seen above, will reach the company and drive improvements in QC. If not, the competition will have a field day, because this is a competitive market that's picky about quality.