Always Random
Just worth saying
Rolled Away
The cheapo slip roll from Grizzly (written about previously) is well on its way back to the bear’s den. I received a reply back from another company that is offering a USA made 1″ x 12″ slip roll. They confirm that their product will not handle over 0.040″ thick material. Trying to roll thicker material the gears become too far out of mesh and may strip. Looks like I will have to explore using bigger rolls. The 1″x 12″ is a very good looking machine and will be good for light stuff. So some day I may have a need, but not now. I may put one in the store if I get a good price. ~ Dan’l
Small Benchtop Machining
I see a slow growing trend of the hobby light duty machine shop in the United States. There is a definite niche for the smaller size high quality high speed machines that are fairly common in the European hobby market. This includes such brands as the Proxxon, Prazi and Emco and others. The English Myford is on the small list. Also included are the US brands of Sherline and Taig. I am talking about small machine tools that are ready to work right out of the shipping box.
Massive slow machines ARE NOT necessary to build accurate, light weight hobby machined projects. Yes, mass is good but it also depends on the size and weight of the parts being machined. Bench top machining is an equal bang for the buck, space and pound than the more resource demanding (mostly space and power) full house heavy floor model machine tools. Using today’s high quality indexed carbide tooling when making small size parts, demands much more SFM than old machines were designed to hold or to run (at the high end). A large chuck and the part it is holding spinning at 2500 RPM is scarry! I have always stated that very small parts are easier/better made on small high speed machine tools. It is an exchange of speed for mass.
Some “old iron” pundits point to the low end rpm (no back gear) and the very high top end rpm of small machine tools as faults. I say they are not faults. They are required features. Small threads are better made with dies even when low speed is available. The pros prefer dies. Single point cutting does not inherently make a “better” thread. However, I would still like a low speed gear for large diameter threads… Continue reading
What I Saw
I see lots of things, sometimes more than I wish. The same goes for hearing but I can feign deafness like Walter Mitty (ta-pocketa-pocketa-pocketa) and drift into a 2nd life fantasy world. Some folks may understand… I think they call it a hobby. (Just kidding, honest!)
What I saw is wood. Just another comment here of what woodworking is like when one uses a very accurate and powerful table saw. The Powermatic almost makes me want to give up metal work and build furniture. Well, I still do that without giving up anything.
I ripped some wood for the remodel project last weekend. What a joy, no fuss, no strain from the saw. One piece of Poplar I needed was a 2 inch wide board 1/2 inch thick. After the cut both the board and the 1/16 waste looked like they came out of a surface plainer. No saw marks what-so-ever! I am now officially spoiled.
If I can stand the initial cost, top line tools are worth every cent. They won’t make me a better craftsperson. I still have to measure twice cut once, but they do save me a lot of extra finish work.
Life is good…
Dan’l
Exploding a possible myth?
I ran across one of the best reports I have read about the reasons for not using propane or a refrigerant tank for a receiver in a compressed air system. Here is the link in Horn & Whistle Magazine.
I have been in the HVAC business all my life and at first thought all those throw away refrigerant tanks must be good for something. In fact there was at least one manufacturer who was offering a kit to convert these tanks to portable air use. The kit consisted of a valve, gage and a short hose. I used one for several years. This item is no longer marketed.
I have seen air tanks and high pressure (HP) steam vessels that have corroded. All the tanks I have worked with that developed leaks in normal use did just that, developed leaks. They did NOT just suddenly and catastrophically explode. The writer never uses the word “explode” however the term “life threatening” conjures up the impression. I believe the explosion impression makes a good scare story and borders on urban legend.
The “Myth Busters” have shot diver air tanks with bullets and they do not explode. They take off like a rocket.
The expansion and contraction theory presented in the link is a new one for me. It is written as obvious speculation but it does sound plausible. Whether it has caused sudden and complete failure is not substantiated in the article. The fact is the pressure in these tanks in their designed use varies considerably and follows and endures temperature changes from frost on the outside (-40 deg) to 120+ degrees. This too is probably a myth until someone can prove that it has happened.
I am always a skeptic whenever I read this sort of thing. The… Continue reading
My Kind of SHOPing
I worked in the machine shop all weekend. I am trying to make spoked solid steel model locomotive driver wheels on my micro CNC milling machine. They are slightly over 3 ½ inches in diameter.
First I had to make a special fixture to hold the wheel blank onto the milling table. That took all day Saturday. Then I cut the first wheel on Sunday. That took about 7 hours!
I enjoyed the work but am not happy with the current result. I broke three 1/8 inch end mill bits working with the stainless steel. 🙁 I will try carbide end mill bits next if I can find some. The finish on the SS was not what I desire. Standard bits get dull cutting SS.
I have some nice machineable steel to try next and also fine grain cast iron. That will wait until another day and when I have more 1/8 inch mill bits to play with.
It is amazing how time flies when you are having fun. Yes, dear! breaking mill bits is fun… forget about those words I used. 🙂