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WTB Micarta gear blank

M. Moore

Titanium
Joined
Jun 8, 2007
Location
Vancouver Island, B.C. Canada
This is for a large German drill press.

Main gear on motor shaft. It is quite large at 67.5 od x 60mm long. From what I have read this needs to be cut from sheet stock and not round bar. So does anyone happen to have a chunk of 2.5” thick Micarta laying around?

Most of what I could find was for knife handles.

I would consider laminating two pieces of 1.25” together to make the blank. I am also considering making the gear from bearing bronze. However I am sure there is a reason they chose Micarta and it did perform very well for 52 years. The drill is in very good condition in general and I use it every day.

Thank you all and good luck to everyone,

Michael


arboga drill 3.jpg
 
Michael,
I have sheets of Micarta 1.5" Thick x 24"x 48" It is
Grade CE often referred to as Canvas or Cotton Grade.
.35 cents per square inch I'll saw whatever size you
want. Plus Shipping.
spaeth
 
You guys are so fast! I guess everyone is at home though....

MrCNC,
I am not sure about delrin, I would have to check to see if it has the same strength as Micarta?

Spaeth,
That sounds excellent and your price is way too low......
I will have to check on the grade, my limited research so far pointed to the L grade which may be the same?
If the properties are the same I will definitely get a chunk from you.

Thanks!
 
Delrin would be a poor choice.

Ideal material would be LE phenolic, which is linen based. Micarta and phenolic are
the same material, one is a trade name. I have no experience with CE grade material.

You need to have the fabric weave across the gear, not around it, for gears.
 
Jim,
thanks for the info on delrin, I suspected it would not hold up.
Good to know that the LE phenolic is the same as Micarta.

In my OP I did mention that I needed sheet stock instead of round stock.
What Spaeth has sounds promising.
 
Putting on my hat from decades of plastic fab work:
L or LE (linen-based) give a finer "grain" structure to the phenolic laminate. The LE designation is essentially an insulating property parameter ("E" = electrical grade)

The canvas (CE) grade material is a coarser fabric weave in the laminate structure, but it may actually create a stronger material for gear manufacturing purposes. At one of the companies where I was shop manager (early-mid 80's) we made a LOT of lathe-turned gear blanks from CE phenolic (yes, sheet stock) for one of our customers. Most of them were in the 3"- 5" dia range, 1.5 - 2.5" thk, with center holes bored around 1.25-1.75". Just some FYI.

Two pcs could indeed be laminated to make the full-width gear, or you may be able to check with an industrial plastics distributor to get a remnant/scrap piece of correct thickness. If you laminate, make sure to remove the smooth as-pressed finish from the sides to be bonded, and pick a high-tensile, slow-cure epoxy.

***Just checked the relative tensile strength of LE and CE phenolic, and the LE grade has a higher range than CE grade, although the bottom end is very similar. CE is less expensive typically.
 
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The 1-1/2" thick Micarta sheets that I have are Remnants
from 4'x 8' sheets. This was supplied to me by my customer and was always referred to simply as micarta. No grade. That company is no longer and I assumed it was all CE. Always worked the same and some is fine weave and some is medium. I did see a spec sheet attached which said Grade CE. Other than slight difference in color and the weave size they look and machine the same. In offering pieces for sale I've opted to call it all CE which is the less expensive of the two. If it is grade LE that the buyer is getting a better grade for a lower price. So is always true that the fine is LE and medium CE? We worked this stuff for many years without issue. Only gear I made from is was for an old Taft surface grinder.
Thanks
spaeth
 
I can clearly see the weave size on the old gear. Not sure if it is fine or coarse without something to compare with.
I wonder if all Micarta was made by Westinghouse back in the day or if Europe had its own manufacturing plant?

PM sent to Spaeth.
 
The thread diameter in the cloth for L/LE grades is about .010 as it appears in the material, just as a ballpark. The C/CE grade materials are more in the .015/.020 thread diameter range.

This link gives a crude visual comparison, for lack of something better:
UltreX™ Paper, Canvas, and Linen Micarta(R) | from Norplex-Micarta

Micarta was a Westinghouse trade name, so if they made it in Europe it would have been under license, or in a factory they owned. The name is now owned and used by Norplex, as I recall.
 
Norplex-Micarta is still alive. We buy lots of composite materials from them in bar and sheet for the oilfield. (We did until the oilfield fracking died off!!!) And Micarta is still one of their big sellers. What specfab has on hand is probably much far superior to that used in your old gear back when it was made 50 years ago. Somewhere in my archives, I have a old flyer put out by General Electric on different things made from Micarta way back in the 1930's-1940's. I don't recall the Westinghouse name but could be wrong. Ken
 
I have used phenolic with cotton, linen, paper and fiberglass reinforcement. I got several hundred pounds of the cotton sheet at a GE auction years ago. I think they mostly used it for steel rule dies. I bought other grades on eBay from mostly one seller who had a wide variety of choices, including big thick chunks of linen grade.

To identify L and C, think of what a bed sheet or handkerchief (L finely woven fine threads) looks like versus sail cloth (C coarsely woven.thick threads).

Larry
 
Larry,
thanks for the visual comparison.
I checked eBay and all I saw was knife blank material.
The real question is which is better for a gear, C or L grade? From Spaeths experience the C seems like a reasonable choice but how much better is the L if it is better?
The guide rails on my Altendorf sliding table saw are Micarta and show no wear after 33 years of use, not sure if they are C or L. (yet)
 
OK, I just received my chunk of this phenolic/micarta. I would consider it to be linen grade material. I like it. Here are a few pics of drilling a core...1 1/2" thick x 2 1/2" diameter...
Jim
 

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OK, I just received my chunk of this phenolic/micarta. I would consider it to be linen grade material. I like it. Here are a few pics of drilling a core...1 1/2" thick x 2 1/2" diameter...
Jim

I would look at that based on the scale of the rest of the pictured items and call it canvas grade, but photos can be deceiving in this day and age. No argument intended, as I'm not the one with the material in front of me. The thread size looks a tad coarse to me to be L or LE grade material. It will absolutely do the job you intend, though.
 
Would a fiberglass like G-10 work for gears? Or is it too abrasive? Just wondering as I have access to cutoffs and scraps by the mile from a former customer who makes electrical parts out of bulk sheet and rod.
 
Would a fiberglass like G-10 work for gears? Or is it too abrasive? Just wondering as I have access to cutoffs and scraps by the mile from a former customer who makes electrical parts out of bulk sheet and rod.
Glass will dull a gear cutter rather quickly.

Larry
 








 
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