Lets talk taper on the 8-L

I have looked at two machines. One of them had a substantial amount and was a used machine. It had .001 taper per inch! I was able to look at a new machine and it’s taper was .0035 over 8 inches. This seems high to me. Machine specs from Tormach are .0015 inches of taper over 7-8 inches (I can’t remember off the top of me head).
The way I test this is a 1 inch bar held in a collet and .005 DOC is made until the 12L14 rod is cleaned up. Then I take a final.005 cut and measure the difference in diameter at each end. I use a digital micrometer and zero it on the left side, then measure the right side to get a comparison. What is everyone getting for taper?
I want a new machine, but I at least, at minimum need it to be in specifications or better. What say you? Any input or opinions are appreciated.

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Unlike a manual lathe the CNC lathe can fix taper in the program. Industrial machines tend to crashed and ill maintained. When dialing in you tool diameters you always check for and identify amount of taper occurs over the length of your part. Once measured you add an X or U value at the end of the turn to counteract the taper of the machine.

I am talking about an acceptable amount on a brand new machine that has never even been ran before. If a taper occurs on a machine you would have to do many iterations to correct it to get one good part, when I could just go to my manual lathe and make it in one process.

was the machine level? If you have a manual lathe then you know how that effects the twisting of the machine. These are hobby grade but fully capable of making production parts. Convert you manual to a CNC.

Unless the new machine is commisio ed correctly, it isnt going to be anybetter than an old machine. Treat it just like a new toolroom lathe. Level it, take the twist out and tram the head to the ways by way of cut and adjust. Wash, rinse, repeat until your in spec or better.

The spindle on these machines are fixed and the spindle cannot be moved front to back. It could be shimmed up and down, but you shouldn’t have to do this on a brand new machine. Yes it was level.

Haas makes a really nice compact chicken lathe for 49k and 2 different tool room lathes with 16 by 30 capacity starting at 31k. If the Tormach isn’t good enough you should look at those. I bought my 15l to produce parts. It does a fine job for the size, weight, and price point.

Good for you. We are all so proud! What a trooper. Next time try to stay on topic. If I wanted a different machine I would look into it. Arrogant pricks like you can stuff it under a bush!
Is it really asking to much to be with in the stated specifications? I bet if your “Haas” had .003 taper in six inches you would piss a bitch over it.

Nickers in a twist much? A machine not in your possession and not set up in your shop and you can’t be happy with it. It has already been explained by more than one member that adjusting the feet can adjust the taper. Programming can also adjust the taper. You came on here to cry and whine about something totally in your control. Go piss and moan to people not trying to explain something you obviously don’t know and do not care to learn.

@Randy_Miller I understand you have a call lined up with @jwallner today. Hopefully some light can be shed on what you are seeing here.

I don’t need ANYTHING explained. I was speaking to other’s results. Don’t assume I have never had one in my shop and don’t assume I haven’t looked at another in someone else’s shop. Your arrogance or ignorance is astounding. You even reported my post. You can’t stay on topic so quit responding to mine. “Adjusting feet will adjust taper” tell us you don’t know what your talking about without telling us you don’t know what your talking about.
I’m not even going to get into the physics with you. You act like a pompous know it all. And frankly I can’t stand people like you. You know ZERO about my knowledge base or experience yet you attempt to “educate “ me.

Yes sir, thank you for your assistance.

Let’s just try to keep things civil in here. No reason for things to ever get personal. Let’s get things straightened out with machine specifications and get back to making chips!

I reported nothing. You have no clue what you are talking about. Adjusting the leveling feet can adjust taper. I have done it many times. You are the one that lacks knowledge. You simply take offense rather than take advice.