Norman Patent toolpost

[Chinggis]

Well guys thank you on your time and help . Post what I make have a 5/100 differences from top to bottom. My explanation is, when I work on them, I do not have cooling system( with oil/water emulsion) so it will be hot and cutting tool is take more than I wish. Steel what I use is unknown 30mm thick, I find it thrown it, my guess is it is ships thin (ship plate).

 

[jwmay]

Could you post a picture of your caliper showing 5hundreds? I don't understand very well. I like your toolpost. I think the machine can be more accurate even without coolant. But you will know better than me.

 

[mickri]

I think that he is referring to 5/100 mm which if I got the math correct converts to .0019 inches.

Chinggis I would like to compliment you on the quality of the finish on what you have made. It looks really good.

You mentioned that you have a taper of .05 mm on the post. If you turned the post between centers then your tailstock is not aligned with the headstock. Simple to fix. Lots of videos online on how to align the tailstock to the headstock. If the post was just held in a chuck then you need to look for play in the cross slide and compound. Check the adjustment on the gibs. Could also be caused by wear in the bed, cross slide or compound. Figure out what is causing the taper and we will help you deal with it. If you think that heat from turning caused the problem then take lighter cuts to see if the taper goes away.

.05mm of taper should not prevent the tool holder from clamping tightly to the post. Your tool holder only contacts 30mm of the post. The taper over 30 mm is approximately .02 mm or .00078 inches. Being unable to clamp the holder tightly to the post is most likely caused by bore of the holder being too big compared to the the OD of the post. The first thing that I would do is increase the clamping bolt from 8 mm to 10 mm. This will make a big difference in clamping the tool holder to the post. Have you read the thread that I gave you a link to? That thread deals with a lot of the issues that you are having.

Don't get discouraged. We will help you work out the problems with your norman QCTP and the tool holders.

 

[Chinggis]

Thank you guys on you help and response. About my lathe it is old one what is for some years doing industrial production of electrical jacks, There is wear in the bed, wear on some other parts. Headstock have some toss too. and I need to replace it, it is planed but for now I cannot do that before I finish my home renovation. I am not sharpen correctly cutting tool and speed was to high so the heat what was generated by cutting make differences on parts with more mass. Well I am quiet satisfied what I am done, just only one will go in scrapyard , big success for me. Now I am able to clamp it tightly, because there I bore hole and saw "excess" material, with that I got more elastic prongs so I can thigh it without excessive force.

 

[ericc]

Congratulations on your success!
Photos, please.

 

[Chinggis]

tomorrow! today I have hard day,

 

[mickri]

Glad to hear that you are getting things worked out. Is the base and the post on yours 1 or 2 pieces? On mine the base and the post were 2 pieces to start with. Then I discovered that the post was turning as I tried to take bigger cuts. So I welded them together. This didn't stop the turning. I made a piece that fit in the slot on the compound and welded this to the bottom of the base. This not only stopped the base and post from turning but it also cut down on how tight the base and post had to be on the compound. Went from having the get it as tight as I could to just tight enough to hold it in place.

 

[Chinggis]

Glad to hear that you are getting things worked out. Is the base and the post on yours 1 or 2 pieces? On mine the base and the post were 2 pieces to start with. Then I discovered that the post was turning as I tried to take bigger cuts. So I welded them together. This didn't stop the turning. I made a piece that fit in the slot on the compound and welded this to the bottom of the base. This not only stopped the base and post from turning but it also cut down on how tight the base and post had to be on the compound. Went from having the get it as tight as I could to just tight enough to hold it in place.

Good evening Mr. mickri,
My base is from one piece, it have wider base and 25mm thick post, and how you think I think too, to make at base hole and put in that hole a elastic rod( I do not know how you call it in English, it is a hollow stick which is split). Here is picture of post.
Today I try my Norman toolpost and I find what I need to do in next one. This one is 2mm thick and I will use it for 10mm thick tools, for this tools is fine.

 

[martik777]

I have a pin that goes through the post, washer and t-nut that prevents the post from turning (only needed for knurling) . My holder never slips on the post.

 

[mickri]

My holders do not slip on the post. What slipped was the post and base on the compound. I cured this by making a small of steel about 1/2" long by 1/8" thick by 5/8" wide which is the width of the compound slot on my craftsman 12x36 lathe. I welded this to the bottom of the base. This prevents the post and base from slipping slipping on the compound.

Chinggis if I understand your description of the pin I call that a roll pin. For a roll pin to work it needs to either be the width of the compound slot or fit into a hole in the T nut in the compound slot. Is yours set up like Martik777's?