New (to me) Grinder

Jellis11

Well-Known Member
Hey guys, new user here...I've been using a filing jig up until today (posted a few pics of my WIPs in another thread) and just bought an old Wilkins Square Wheel Grinder about 30 minutes ago. Guy selling it didn't know what it was and I think I got a smoking deal ($500.00). I'll pick it up tonight and start using it this weekend hopefully....any advice or pointers?
 
You mean a Wilton Square Wheel? A lot of talented makers got their start with one of those. Post some pics when you get it!
 
I started out with a Wilton Square Wheel. There are several things I found it lacking for knifemaking, and although it's old, I still have a page on my website dedicated to making the Square Wheel a very good knifemaking machine.....

http://www.caffreyknives.net/square_wheel_art.html

Probably the biggest drawback of the Square Wheel (as it comes from the factory) is the speed..... 4600 SFPM belt speed! At that speed, you make a slight bobble when grinding, and it's a major issue. After destroying a number of blades, slowing the machine down became my top priority.
 
Thanks for the comments guys...it was missing the 8" wheel and other small wheel attachments. So, I talked him out of his old metal bandsaw too (see pic) It needs a little TLC. Looking into MAYBE trying to mount it vertically somehow...

Andrew, yes....I meant a Wilton Square Wheel....I was so excited about the deal I was getting that I couldn't even get the name right.

Ed, thanks for the comment....I'll give it a try as is for now and perhaps later, if I need it, I may switch out and run a motor/VFD. I am in the mechanical rep business and have many contacts with Baldor, Yaskawa and ABB, so it shouldn't be an issue.

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Ed, I checked out your link and I like your ideas! As I am VERY new to machine grinding, there are a few things that don't quite sink in yet (use of glass on the platen and why, inability to grind plunge cuts from the left side) but I will sort it all out, although I may be hitting you guys up with more questions along the way....

Thanks!
 
use of glass on the platen and why

The two biggest reasons are heat and wear. The belt running over a steel (or in this case a cast) platen generates a great deal of heat, sometimes enough to cause a belt joint to heat up and pop. With the amount of time I spend using a flat platen, the belt also wears on the platen, creating grooves, etc. that translate into seeing the reverse of those things in the steel you're grinding.

inability to grind plunge cuts from the left side

As your standing in front of the machine, due to the nature of how the platen is built/cast, you cannot track the belt to the left far enough to make the edge of the belt line up with the edge of the platen..... basically you can only grind as deep on the blade, as the belt is thick, before the blade "chocks" against that part of the platen that's exposed beyond the belt....and you can't grind any deeper. Overlaying the platen with a 1/4"-5/16" thick platen prevents the blade from "chocking" and allows to to grind as deep as the platen overlay is thick.... it also allows you to track the belt to, and even beyond the edge of the platen on the left side. (it will become obvious once you start using the machine for blades).

The biggest issue is the speed. It's not that bad when using heavy grit belts (36-60 grit), but as you get finer in belts, the heat build up is incredible, and because of the belt speed, it's a safe bet that you will "burn" stuff up with a 220 grit belt of finer. I used one of the Square Wheel grinders for nearly a dozen years, before VFDs were available.....if I had it to do over, and had VFDs, I'd go that route right away on the machine.

That machine looks to be in very good condition for it's age. I suspect it's seen minimal use. Another weak spot in the Square Wheel grinders was/is the tracking...the parts inside the idler arm that adjust tracking were all made of delrin (a nylon type material), that wears out quickly. I replaced those parts twice with factory replacements, but after wearing the second set out, I made my own parts out of steel, and they are still working to this day.

Several years ago, I moved the Square Wheel from my finishing shop to my Blacksmith shop for common tasks there, but it's been with me now for over 25 years, and aside from routine maintenance, and replacing bearings here and there, it's endured! :) The modifications I did/show on the webpage made it a passable blade grinding machine, but there are so many better options available these days, I personally wouldn't buy another Square Wheel unless, like you, I found a screamin deal.
 
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Thanks Ed, that was very helpful! I will eventually move up in machines, however right now my next investment will be an oven (using the 2-brick propane forge now).

Anyway, back to the platen.....when I look at the belt and platen on this machine from the side it appears that there is maybe 1/4 to 3/8" gap between the two, is this normal? From the way that you're describing the "fix" it seems that the belt should actually be touching the platen?, and if so, wouldn't you be pushing it out more, if not actually putting a bow in the belt and causing even more friction with an additional 1/4" plate? I'm sorry, I'm only trying to understand...
 
back to the platen.....when I look at the belt and platen on this machine from the side it appears that there is maybe 1/4 to 3/8" gap between the two, is this normal?

No..... that's not the way you want it. The contact wheels on the flat platen of a Square Wheel are on "cams", meaning that you can loosen the bolts holding the contact wheels to the platen body, and the holes are "off center"....you can rotate then so that the contact wheels move in or out in relationship to the platen. I always recommend laying a straight edge along the platen face (one that is long enough to extend beyond the top and bottom contact wheels), then move the contact wheels back, until the straight edge no longer makes contact with the contact wheels (have a slight amount of "daylight" between the straight edge and the contact wheels). This is another reason why I added a 5/16" thick platen face to the existing platen body.... with my grinder, the contact wheels would only move reward enough to be level with the platen face...... this causes issues if you ever try to grind anything longer then the platen.... if the contact wheel (usually the top one) makes contact with what you're grinding, it will create a "divot" in the steel you're grinding, which is a bear to get out.


Here's a pic that might be helpful: (this pic is of my custom KMG platen, but the same principle applies to any flat platen on a grinder.)


Ed has two shops!!!
11.gif

YES HE DOES!:biggrin: It's all thanks to a wonderful Wife! During my last tour of duty in the Middle East, my wonderful Wife asked if I was going to be a full time Bladesmith when I retired.....when I said yes, that was all it took. When I got home she had already done the footwork and research for a new steel building for a new "hot" shop! Of course there was a concession..... one of the 12 foot bays (the hot shop is 20'x48') was "her's" to park her vehicle in. Small price to pay for a nice shop building!:nothing:
 
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Thanks Ed, makes more sense now....so the belt is ALWAYS in direct contact with the full surface of your platen (glass face in this case) thus the need to reduce heat, ie glass, etc.

During my last tour of duty in the Middle East,

US Army, 528th USAAG, Cakmakli, Turkey 92-94
 
Yes..... if the belt isn't totally against the platen, there will always be a slight convex to whatever you grind. It's often not a enough to be obviously visibly, but it can drive you crazy when trying to assemble something that needs to be very flat (gaps will show).

Thanks for your service!
 
And thank you for yours...I appreciate all the help. I'm going to get started on the platen "plate"(?) this weekend while I wait on belts, couldn't find any locally.
 
Unless you're among the lucky ones that live somewhere close to a "knife supply" outfit, just about everything will be "ordered". :) Depending or where you're located, my recommendation for belts is Tru-Grit if you're west of the Mississippi, and Pop's Knife Supply if your east of the Mississippi. Nobody can match the prices that Tru-Grit offers, but being in California, shipping can be a week or more for those in the east.
 
That's awesome Rick! Even being here in Montana, whether they ship UPS or Priority Mail, it still takes at least 3 days to get here.
 
For your glass platen liner, go to eBay, and type "Robax" into the search bar. Sort for lowest price, and you'll find a seller with the absolute best prices I've seen anywhere. Make sure you follow the ordering instructions so that you get the correct length, and I'd recommend buying 2 or 3 so you have a spare down the road. They wear VERY slowly, but they do wear.
 
No..... that's not the way you want it. The contact wheels on the flat platen of a Square Wheel are on "cams", meaning that you can loosen the bolts holding the contact wheels to the platen body, and the holes are "off center"....you can rotate then so that the contact wheels move in or out in relationship to the platen. I always recommend laying a straight edge along the platen face (one that is long enough to extend beyond the top and bottom contact wheels), then move the contact wheels back, until the straight edge no longer makes contact with the contact wheels (have a slight amount of "daylight" between the straight edge and the contact wheels). This is another reason why I added a 5/16" thick platen face to the existing platen body.... with my grinder, the contact wheels would only move reward enough to be level with the platen face...... this causes issues if you ever try to grind anything longer then the platen.... if the contact wheel (usually the top one) makes contact with what you're grinding, it will create a "divot" in the steel you're grinding, which is a bear to get out.


Here's a pic that might be helpful: (this pic is of my custom KMG platen, but the same principle applies to any flat platen on a grinder.)




YES HE DOES!:biggrin: It's all thanks to a wonderful Wife! During my last tour of duty in the Middle East, my wonderful Wife asked if I was going to be a full time Bladesmith when I retired.....when I said yes, that was all it took. When I got home she had already done the footwork and research for a new steel building for a new "hot" shop! Of course there was a concession..... one of the 12 foot bays (the hot shop is 20'x48') was "her's" to park her vehicle in. Small price to pay for a nice shop building!:nothing:
Ed is the kind of guy who likes too tinker with things to make them better.I truley believe if he played golf he would mess the that ball until it flew 600yrds he is just good at making things better.
 
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Ed is the kind of guy who likes too tinker with things to make them better.I truley believe if he played golf he would mess the that ball until it flew 600yrs he is just good at making things better.

600 years?!! At that rate, it'd take forever to play 18 holes. :D
 
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