Hard aluminum Vs. mild steel?

[Maryak]

My 2 Bob's worth,

Lew,

You have beyond any shadow of doubt demonstrated an amazing grasp of a vast range of highly technical facts and figures. This has obviously impressed some of our members and not others.

Your climb from humble beginnings as an apprentice tool and die maker to the dizzy heights of aerospace engineering is to be admired.

Now really impress me by 1. learning how to post a picture
2. Making a model engine or showing me one you have made.

Best Regards
Bob

 

[steamer]

Lew,

One Engineer to another....and I've been doing it a long time... I do understand what your saying. And at some level, your right, it all matters.

But give me a brief moment of professional courteously.......and hear me out.

( By the way, there are a LOT of Engineers who are members here)

As Steve said....just throttle back to a regular guy......we could use your experience here....it can't hurt and we'll ALL learn something.

Let me tell you about this place......as I'm neither a moderator nor a high achiever here. Perhaps you'll appreciate the perspective.

This place is a well mannered bunch who in general will open a personal vein to show how human we are. We LOVE to help each other with problems. We're not one of those "other" sites that judges and grades, we like to have fun and be creative....and lord knows there is TONS of creativity and genius on this board. I'm befuddled daily with some othe creations that get posted!

I count these people as my friends....and I would like to think they think the same of me.

I have yet to meet anyone on this board who has not learned something from it. I doubt I'll be proven otherwise. Hang around and have a bit of fun.....I'd be glad you did. I think you would too.

There....and there ends my off topic commentary....steping carefully off the soap box.......OK! anybody want to talk about aluminum? ;D


Sincerely,
Dave

 

[Twmaster]

Great googly moogly!

First, Um, wow. What a mess I've made. T'was not my intention.

I want to thank all of you for your input. Yup, even you Lew. Even though most of your comments went waaaay over my head I still appreciate that you took the time to reply.

I did see the answers I was hoping to see. Simple yes and no is not what I sought and I was not let down. There's more than enough info to keep me reading for quite a bit.

In summary, nope, not building any space hardware. Although if my efforts to rebuild my lathe encounter any more snags some parts might just make it into low earth orbit as I see just how far a huge angry man can toss said parts.

Basically I have an idea for a tool post. It's not something I currently make. (Yes Dean, those other parts will continue in 1018CRS)

I wish to prototype it is hard aluminum as that is what I have in stock and can afford to burn if when I screw something up.

I hope none of you have any sore feelings toward anybody. Life's too short for all that.

 

[Deanofid]

Not knowing exactly what you're making, Mike, I'd say just turn out a prototype with what you have
on hand and give it a workout. Practical engineering is a great teacher, and you can prove the end product
in your own shop. Most everyone here is a practical engineer, and for us, there's no other way to know
what will break until we break it.

I was originally guessing that you may intend to change something you already make. The main thing I
thought about was customer complaints by way of component failure due to a change in your materials.

(If you're making something for the 618, send me one and I'll be glad to try to break it for you. Consider
me a no charge test lab..)

Dean

 

[Twmaster]

Heh, OK Dean, I'll keep you in mind as a beta tester. While not specifically for the 618 I expect it to be compatible.

 

[Artie]

Im with Dean, I have heaps of "oops, that didnt work" prototypes laying around...each taught me something and many have been recycled over the years.... tis never time wasted.. although it may seem so at the time... ;D

Artie of the prototype pile :-\

 

[steamer]

Artie of the prototype pile :-\

Hey Artie....you have one of those piles too? ;D

Dave

 

[tel]

Don't we all?

 

[Artie]

yes Dave I got a beauty... ;D

On this subject, on another thread I made comment on using brass for the low load tool holders (boring bars etc)... Im just gonna do it and report in when I have news.... gotta use that brass up somehow.....

Gday mountain man... cold up there tonight?

R

 

[tel]

Yeah, cold enough, but not as bad as it has been - bit of cloud keeping the frost off.

 

[Stan]

Mike: Several times I have posted replies and even pictures of the tool holders (not tool post) made out of 6061 T6. They have stood up well on a 10" Logan and being very much an amateur, they have have received a lot of abuse.

Separate from the aluminum question, I am surprised that you use 1018 CRS with all the machineability and warping problems people talk about.

 

[Philjoe5]

I’ve been reading this thread with much interest. I've used 6061 and 7075 series aluminum alloys in model building and the 7075 I have is a joy to work with. It machines beautifully, is harder than 6061 and can be had for about the same price.

Now, as to making toolpost holders. Check out this set sold by a most reputable vendor in our hobby, Little Machine Shop.

http://www.littlemachineshop.com/products/product_view.php?view=classic&ProductID=2461

These are anodized for durability, but they are commercially available from 6061 T6 aluminum. It’s been done

Cheers,
Phil

 

[arc100]

I saw a few posts by a guest called Lew_Merrick_PE. Does anyone know how I can email or get in contact with this guy?

 

[dsquire]

I saw a few posts by a guest called Lew_Merrick_PE. Does anyone know how I can email or get in contact with this guy?

Lew is a member of http://madmodder.net and can be found there.

Cheers

Don

 

[Entropy455]

Several months ago I also received a personal message from aboard moderator asking me to “Please tone it down a little on the high tech jargon”

The topic of discussion was how to home stress-relieve a weldment. A recommendation was made to blast the part with a rose bud for a few minutes until it glows red, then let it cool. The problem is that stress relieving requires precise elevated temperature controls for many hours – as well as a controlled rate of cool down. I.E. blasting the part with a rose bud would likely introduce far more stress, then simply machining it in the as-welded condition.

Needless to say, my recommendation to “farm-out” the stress relieving process – while made with the best intentions - was not well received by at least one moderator on these boards.

I am a Mechanical Engineer, licensed in the state of Washington. My job is to help maintain propulsion systems on nuclear powered warships. Where I work, we have hundreds of machinists, and thousands of mechanics. It never ceases to amaze me at the amount of “bad blood” that exists between engineers and machinists. Engineers are viewed by machinists assmart-a$$ punks, who are overpaid, and don’t know anything. Machinists are viewed by engineers as grumpy mean guys who will not give anyone the time of day – and will get flat-out angry when you ask them a question.

Engineering school taught me a lot, however it did not teach me the tricks of the trade for operating a milling machine or a lathe. I’ve become good friends now with several of the machinists at work. All I did was ask them - what’s the best way to reduce chatter, or what’s the best way to get a better surface finish with this end-mill, or how do I get the cutting tool to do this . . . Point being, it was only after they realized that I was an engineer who was taking a personal interest in their trade, that I was treated with some level of respect.

When someone takes the time register a username and password on these boards, and makes a post that contains technical information – why not assume that it was done so with the best of intentions? Why must some folks on these boards immediately go on the offensive and challenge credentials, or ask to see pictures of a workshop? Why not simply ask for clarification on the posting, in lieu of going on the attack?

Here’s my two cents:

I would not use aluminum to construct a tool post holder. Justification: The Young’s Modulus for aluminum is about 1/3 that of steel. The Young’s Modulus is the “rubber-band-ness” of a metal. The lower the Young’s Modulus number, the more the metal will deflect with a given force. Thus a tool post holder made of steel (or cast iron) will deflect three times less than one made of aluminum. This means that steel will provide a more rigid foundation for the cutting tool - thus more consistent cuts under load. This is a big reason why metal working machines are usually made of cast iron, and not cast aluminum. . .

FWIW, Lew said the same exact thing in the third sentence of his original post to this thread (he just did so with less words, using more traditional engineering verbiage). He went on further to explain how steel has more distortion energy, and its grain structure gives it a greater resistance to shear. His post provided ALL required information needed to make an educated decision on whether or not to construct a tool post out of aluminum. I don'tbelieve he did a copy-and-paste from the internet, as Lew did not talk about the poor cyclical fatigue properties of aluminum with respect to the endurance limit. He specifically did not mention cyclical fatigue, because it’s not applicable in a tool post holder application.

Lew’s initial comments were not condescending. The way I see it, it was folks on these boards who put Lew on the defensive by challenged his credentials, asking to see pictures of his workshop, taunting him for not knowing how to post a picture, and implying that his post is somehow discredited if he can’t post a picture of a model engine that he’s already built.

Again - It never ceases to amaze me at the amount of “bad blood” that exists between engineers and machinists. . . . .

 

[arc100]

Several months ago I also received a personal message from aboard moderator asking me to “Please tone it down a little on the high tech jargon”

The topic of discussion was how to home stress-relieve a weldment. A recommendation was made to blast the part with a rose bud for a few minutes until it glows red, then let it cool. The problem is that stress relieving requires precise elevated temperature controls for many hours – as well as a controlled rate of cool down. I.E. blasting the part with a rose bud would likely introduce far more stress, then simply machining it in the as-welded condition.

Needless to say, my recommendation to “farm-out” the stress relieving process – while made with the best intentions - was not well received by at least one moderator on these boards.

I am a Mechanical Engineer, licensed in the state of Washington. My job is to help maintain propulsion systems on nuclear powered warships. Where I work, we have hundreds of machinists, and thousands of mechanics. It never ceases to amaze me at the amount of “bad blood” that exists between engineers and machinists. Engineers are viewed by machinists assmart-a$$ punks, who are overpaid, and don’t know anything. Machinists are viewed by engineers as grumpy mean guys who will not give anyone the time of day – and will get flat-out angry when you ask them a question.

Engineering school taught me a lot, however it did not teach me the tricks of the trade for operating a milling machine or a lathe. I’ve become good friends now with several of the machinists at work. All I did was ask them - what’s the best way to reduce chatter, or what’s the best way to get a better surface finish with this end-mill, or how do I get the cutting tool to do this . . . Point being, it was only after they realized that I was an engineer who was taking a personal interest in their trade, that I was treated with some level of respect.

When someone takes the time register a username and password on these boards, and makes a post that contains technical information – why not assume that it was done so with the best of intentions? Why must some folks on these boards immediately go on the offensive and challenge credentials, or ask to see pictures of a workshop? Why not simply ask for clarification on the posting, in lieu of going on the attack?

Here’s my two cents:

I would not use aluminum to construct a tool post holder. Justification: The Young’s Modulus for aluminum is about 1/3 that of steel. The Young’s Modulus is the “rubber-band-ness” of a metal. The lower the Young’s Modulus number, the more the metal will deflect with a given force. Thus a tool post holder made of steel (or cast iron) will deflect three times less than one made of aluminum. This means that steel will provide a more rigid foundation for the cutting tool - thus more consistent cuts under load. This is a big reason why metal working machines are usually made of cast iron, and not cast aluminum. . .

FWIW, Lew said the same exact thing in the third sentence of his original post to this thread (he just did so with less words, using more traditional engineering verbiage). He went on further to explain how steel has more distortion energy, and its grain structure gives it a greater resistance to shear. His post provided ALL required information needed to make an educated decision on whether or not to construct a tool post out of aluminum. I don'tbelieve he did a copy-and-paste from the internet, as Lew did not talk about the poor cyclical fatigue properties of aluminum with respect to the endurance limit. He specifically did not mention cyclical fatigue, because it’s not applicable in a tool post holder application.

Lew’s initial comments were not condescending. The way I see it, it was folks on these boards who put Lew on the defensive by challenged his credentials, asking to see pictures of his workshop, taunting him for not knowing how to post a picture, and implying that his post is somehow discredited if he can’t post a picture of a model engine that he’s already built.

Again - It never ceases to amaze me at the amount of “bad blood” that exists between engineers and machinists. . . . .

I feel your fustrations. Probably not on the same tech level as you but same situation. I'm not a qualified mechanical engineer or machinist, however I do quiet well in my job and hobby involving both types of skills. I'm the only tech guy in the company so I have to build whatever I design. Most of my work is for basic automated filling machines, packaging machines and class 3 solvents. Some of the guys on the production floor seem to think I'm trying to belittle them when trying to ask questions about operations and techniques and problems that arise during machine operations. Some day I hope to buy my own 4-axis CNC mill. (VMC)

I myself think of you guys in highest regard more so as generous people rather than for the tech skills you have. Simply because you guys are giving advice and your time on these forums for free. There seem to be a fair few people in this world that are highly educated in a field of expertise and I do notice a bit of arrogance among them as if they are a higher class of human being. Idk, maybe it's just people in general, everybody these days seems to have to be someone important in order to be worthy of breathing fresh air or something. I just like learning tech stuff as a hobby plus it helps me a lot at work as well as with my race karts.

Anyway, I got in touch with Lew and I will be in touch with you too. Lew is a great guy and a real life "rocket scientist". Which is a bit of buzz to speak to someone who works on space craft. Maybe it's common in the USA with such a big space program. But here in Australia not so much.

Regards
Mark.

 

[Maryak]

Hi Guys,

Just so you don't die wondering, the moderator concerned was me.

Having started life as a deck hand on a prawn trawler, I did end up with a degree in engineering having first worked my way up from the workshop floor as an apprentice fitter and turner; and I stand by my, what were until now, private comments, made at the time.

Best Regards
Bob

 

[gus]

I’ve been reading this thread with much interest. I've used 6061 and 7075 series aluminum alloys in model building and the 7075 I have is a joy to work with. It machines beautifully, is harder than 6061 and can be had for about the same price.

Now, as to making toolpost holders. Check out this set sold by a most reputable vendor in our hobby, Little Machine Shop.

http://www.littlemachineshop.com/products/product_view.php?view=classic&ProductID=2461

These are anodized for durability, but they are commercially available from 6061 T6 aluminum. It’s been done

Cheers,
Phil

I would have used aluminium if I could get the suitable grade.So I took a deep breathe and jumped in used ground M.S. bars. Using dovetail miller cutter is something very new to me. Quick Change tool post can be very expensive.So I make mine for US$10 for tool post and 6 tool bit holders.Local bought Proxxon tool holders cost US$99.95 w/o freight cost and its made in PR CHINA!!!
Best to take heavier cuts with dovetail end mill to avoid rubbing instead of cutting. Fixed steady is also homemade. Bronze hollow disc was left-over from job making spoked fylwheels.
I am glad I chose steel which stood up very well .Parting tool holder also home made.However I did buy LMS holder on offer at US$19.95.

Gus.

 

[Busydad]

I have tool holders made of both mild steel and 6061t6 pieces. The only thing i have found is if the mounting hole is a close fit in an aluminum holder the top of the hole can be deformed over repeated use , i have fitted steel bushings with a large washer type top to spread the load .. I am no machinist , a diesel mechanic for 11 years and for the last 16 a long haul truck driver..I appreciate any input with regards to materials and tool selection..I have many OOPs for lack of the proper information..Discussion both pro and con is one of the reasons that i enjoy these forums..The wealth of knowledge that the members here is great and always helpful...

 

[gus]

I have tool holders made of both mild steel and 6061t6 pieces. The only thing i have found is if the mounting hole is a close fit in an aluminum holder the top of the hole can be deformed over repeated use , i have fitted steel bushings with a large washer type top to spread the load .. I am no machinist , a diesel mechanic for 11 years and for the last 16 a long haul truck driver..I appreciate any input with regards to materials and tool selection..I have many OOPs for lack of the proper information..Discussion both pro and con is one of the reasons that i enjoy these forums..The wealth of knowledge that the members here is great and always helpful...

Hi BusyDad,
While cutting dovetails for my very first QCTP,I was tempted to use hard aluminium which easier to cut but not as wear resistant as steel and went steel instead and very happy I made the right choice.
The fine dusty chips do get in but easliy brushed off and the steel tool holders
still in good shape after 12 months usage.
Upgraded with a better version DIY QCTP with six tool holders.See attached foto.