Upper Midwest Scrapers And Rebuilders Hobby Club

Uglydog

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Machinist Bedside Reader fans may recall Guy Lautard reference to Dennis Danich a Millright. I’ve been privileged to enjoy beginning to learn scraping and rebuilding under his auspice. Dennis would like to find 6 or 8 individuals who would like to learn and build on their scraping and machine tool rebuilding skills. His emphasis is always on understanding what and why.

First project:
Using his pattern making skills he is proposing that he hire a local foundry to cast 24 inch triangular straight edges. All participants will purchase one of these at his cost: $120. This is for a 24inch long, stress relieved, triangular gray cast straight edge with 90degree, 55degree and 35degree angles. Faces will be around 2.75inches. Note: this is a not for-profit venture. He is coaching me to do one pass milling on them and charge a very few additional dollars for my time. Each member of the group will have their own straight edge, and will be working on the same project and learning scraping and geometry together. Please understand that this is a club, not a class. We are accountable to each other. Dennis is only facilitating the learning. You will also need a scraping tool. An inexpensive tubular Anderson with HSS cutters would be fine.

Dennis is having his knee rebuilt shortly after Thanksgiving. Then we need to build a pattern. The foundry wants 4-6 weeks to schedule and complete the job. Thus, our first session will likely not happen until January. Our first obstacle is to gage interest, and collect some down payments so that we don’t end up owning a dozen straight edges.

Initially the plan is that we hold these sessions at my shop in Dayton MN. I have a 5footx5foot acorn table and a 36 inch cast plate. We believe that we can get everyone comfortably around the acorn table. Other locations will be used as they become available.

It’s the expectation that after the initial session we would all work on the project at home, then reconvene to take work on triangles and the geometry. The long term goal is that we work on rebuilding an entire machine as a group. This suggests a long term time commitment to the group. Other than the straight edge costs there is no plan for ever charging a fee or paying for instruction.

Please PM should you have interest, questions, or concerns. I will answer you directly and/or forward your contact information to Dennis for him to respond directly.

Daryl
MN
 
I've already received a couple PMs.
Dennis would like me to emphasize that while he wants us to learn scraping that's low hanging fruit. His ultimate objective is that we understand "machine tool geometry" and "tolerances". The big picture is that we work together to effectively use scraping and other methods to accomplish machine tool rebuilding.

Scraping in a triangle is easy. Now let's scrape all 3 sides within tolerance to specific relative to each other!
This is going to be great fun!!

Daryl
MN
 
Hi
I think this is great, if i was in the USA near you i would jump at the chance, i hope you get it going, good luck :eagerness::eagerness::eagerness:
 
Daryl,
What a great way to build comradery and knowledge.
I wish I was closer too.....
-brino
 
Dennis and I have identified 0900 Saturday February 6th as our first session with February 20th as an alternative “Blizzard Day” option.

Dennis encourages you to contact him at (edit: email removed for "bot" protection - please PM me I'll be pleased to share you his email) should you have questions. As a reminder: there are no dues, or tuition. He is expecting that everyone would invest in a hand scraper and steel cutters.

Daryl
MN

Edit:
I originally reported that Dennis email was .com
It is .net
I corrected it above.
Sorry
 
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Dennis Danich sent this email to the people who have expressed some interest and for whom I have an email address.
I've copy pasted it here.
Please note Dennis is way to humble.
I know hundreds of trained Instructors.
Many Phds in education, others with Masters in Ed.
All kinds of "Certified Instructors" in EMS and Fire/Rescue.
Sometimes their teaching is.... well... lacking.
Dennis is the real deal.
The above comments are not intended to detract from the excellent teaching of other scraping and machine tool Instructors.
I offer the above comments to highlight that Dennis isn't like your high school or college geometry Professor.

From: Dennis Danich
Sent: Tuesday, December 29, 2015 11:04
To: Daryl Doering
Cc: .......................................
Subject: Re: Scraping and Machine Tool Rebuilding

I am a trained instructor so to help this along and to act as a FAQ I am writing outlines, as we collectively progress in this I will make notes for lesson plans. Daryl and Ben may recall me telling them at times I needed to stop and think how can I explain a skill that is automatic to me so it can be understood.
From my experience I feel it is best to start scraping with high speed blades, carbide will follow later.
Machine geometry will follow after you can scrape as then you can correct geometry errors.
The initial outline follows.

Course outline for scraping class 101
History of scraping and fitting parts to build machinery
The difference between qualitative and quantitative measurement
Joseph Whitworth and creating flat surface plates
Early scrapers marking medium and techniques
Evolution of more modern methods in the 1800's creating plane surfaces and machine ways in the technique of systematic distribution of error

1. Sharpening scrapers
Techniques for sharpening blades and using different radii for different purposes

2. Surface preparation and scraping strokes
Historical use of scraping to make a smooth surface as opposed to making a truly flat or fitted surface to another part and comparing scraping to filing and other polishing techniques

3. Marking medium an observation of blue spots
Observing with marking medium tells you a lot of this takes practice determining if you have twist determining false readings and making corrective action

4. Scraper handling
Controlling the process of using the scraper by observing the width of the stroke you can generate by various angles of using the blade and how the radius of the blade affects the width of the cut

5. How to use a straight edge
Using straight edges to determine what you have to do to a part the straight edges initially can be ground straight edges and using scraped straight edges for marking parts for scraping

6. Step scraping
Using step scraping to correct tapers or hills or valleys on the part determining if you should scrape or machine

7. Pull scraping
Pull scraping techniques and using pull scraping for a distinctive pattern on the work

8. Flaking or Frosting
Flaking work to create oil pockets or put a distinctive decorative pattern on some areas of the machine
 
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Daryl,
What is the approximate time line for the day? Start at 0900 until?
 
Probably 1200ish??

Not sure that I still have you email address.
Please PM me your address. I'll add you to the email thread.

Daryl
MN
 
Midnight?? Dang, I better bring beer. :drink:

Just kidding. Noon sounds good. It will give enough time to make some progress but without getting too long.
 
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