contact wheel

Discussion in 'Ed Caffrey, MS "The Montana Bladesmith"' started by cliff, Feb 21, 2011.

  1. cliff

    cliff Member

    What durometer and what size contact wheel do you use on your surface grinder
  2. EdCaffreyMS

    EdCaffreyMS Forum Owner - Moderator

    I use a 100 durometer serrated contact wheel, 6" diameter. Anything less than 100 durometer is too soft in my opinion. Some makers use either a solid aluminum or steel wheel as their contact wheel....I tried it, and discovered that either will wreck belts with anything other than the lightest passes, and EVERYTHING on the surface grinder must be dead on true, or they can chatter badly.
  3. Bruce Bump

    Bruce Bump Forum Owner-Moderator

    Ed, What width so you reccomend, 1.5"? I read that somewhere, why not 1" or full 2" wide? Do you split belts?
  4. cliff

    cliff Member

    I had a 8 inch wheel that was softer that worked good when it needed replaced I bought a 6 inch 100 durometer . It leaves lines on the blade . I don't notice
    Them with a 120 grit belt . I try to get the grit off the splice area but can still hear it hitting and I think that
    Is what's causing the lines. Any suggestions would be appreciated
  5. EdCaffreyMS

    EdCaffreyMS Forum Owner - Moderator

    Bruce: The contact wheel on my SG is 2" wide....I like it that way because I just buy one batch of belts and use them for the grinders and the SG.

    Cliff: Those lines your getting is nothing more than uneven grit on the's one of the "trade-offs" when using a belt on the SG. The biggest drawback I have encountered using belts on a SG is uneven belt happens most often on structured abrasive belts like Norax and Gator, and will become more prominent with the finer grits.
  6. cliff

    cliff Member

    The lines don't go the lenght of the blade they look like you stopped
    moving the blade with the wheel on top of it about an 1/8 inch apart
    the whole length of the blade
  7. EdCaffreyMS

    EdCaffreyMS Forum Owner - Moderator

    Cliff....those are from the belt joint....the joint is just a fraction of a thousandth thicker. Although it won't eliminate them completely, the way to minimize them to take several VERY light passes just before your finished with the piece. You actually get something similar with stones on a SG, but they run the opposite direction.
  8. cliff

    cliff Member

    I'll try that, thanks
  9. Josh Dabney

    Josh Dabney Moderator


    I'm getting ready to order my contact wheel and after reading everything I can find on the subject I'm still left with several questions. I want to have my ducks in a row before calling to place the order so I thought I'd ask my questions here for all to see instead of in a PM.

    My questions are based on this ordering page- ( Not positive this is the correct page to be looking at)

    I notice that your wheels and others I've seen have a core that is a thinner width than the wheel surface but width of the core isn't an option on the order form

    #1 When requesting this feature what width should I specify ? (or perhaps this is a different type of wheel than a drive wheel)

    The fact that this isn't an option on this form leaves me wondering what other potential options aren't listed.

    #2 I have read where you mentioned balancing which is also not on that option menu- Do I need to specify that the wheel be balanced ?

    #3 Is there anything else I need to request thats not on the order form ?

    On the topic of wheel Durmometer I'm looking at this info page from Sunray-

    Based on this info I'm ASSUMING that your wheel is 100 Durmometer on the Shore A scale ????? This option seems to be 60 on the Shore D scale.
    I asked Sunray about hardness and 75 on the Shore D scale is the hardest they offer.

    #4 Should I go with a 95A 60D or 75D My inclination is to go with the 75D but not sure ????

    Those questions asked I filled out my quote request like this-
    Core material- Aluminum
    Tread pattern- 45 degree
    Durmometer- 75D
    Color- Green
    Outside Diameter-6"
    Core Outside Diameter-4" (Perhaps 5" would be better?)
    Shaft Diameter:1.25"
    Keway Needed? No
    Setscrew Needed? No

    Your insight is greatly appreciated.

    I think a WIP entitled- "How to order a contact wheel from Sunray for Surface Grinder conversion or Belt grinder" would be a fantastic addition to the Articles section of your website or even a sticky right here on your forum as this question has been asked alot, lots of answers given, and I still have questions, LOL

    Thanks again- Josh
  10. EdCaffreyMS

    EdCaffreyMS Forum Owner - Moderator

    Hi Josh!

    I'm only familiar with a couple different brands of surface grinders, and each has different shaft diameters and it's going to require that each individual do the measuring on their specific machine(s) to ensure they order a contact wheel that will fit. That will include ALL the specifications.

    Next, you have to realize and understand that SunRay's main business is producing urethane type wheels for military applications. This means that they are used to dealing with military contracts, and rather than "offering options", they work to specifications. That's the reason why I always try to explain to folks who are dealing with them that EVERY specification you want, is going to be up to you to figure out, and ensure that you include them in the order.

    DO NOT anticipate that Sunray will give you anything beyond a very basic set of options to choose from....everything else is up to you to figure out and include with the order.
    I once had an individual call me and try to chew me out because he had ordered a 10" contact wheel from Sunray and said the wheel was not "balanced". When I asked him if he had specified that the wheel was to be balanced, his response was "NO! They should have known to do that!" NO THEY SHOULD NOT! Sunray only offers contact wheels as another way to generate income for the company, it is not their primary business. Although they are very helpful, it's going to be up to the individual ordering to make sure they have covered all the specs and all the basis.
    Hopefully I've beat that horse to death now. :)

    The very best way to order from Sunray is to call (I deal with a gentleman named Shane) and have ALL the specifications you need for your application. The first time I spoke with Shane, I was ordering 1 1/2 and 3" wheels for the grinder platen I build. I spent nearly 30 mins on the phone, learning about Sunray and how they work, and called back 3 more times before I finally placed the first order...taking my time and making sure I had all the specs worked out.

    Now to your questions:
    That is a specification your going to have to figure out and order. Like I said, each brand/type of surface grinder MIGHT have different shaft diameters and lengths. You can get any "option" (specification) you want, you just have to know what it is you want. You also must realize that additional machining to thin down the hub will add time to the order, and will add costs. That being said, I believe that just about any surface grinder application is going to require that the hub be thinned in order to fit/work on a surface grinder. What you will have to figure out is how thick that hub must be, and the offset (I know that on my HF machine the hub offset is "centered", with the hub thickness being approx. 1/4")

    If you want this, yes, you must specify it. It will require more time for Sunray to complete, and it will be an additional cost.

    Forget the order form! Figure out EXACTLY what you want/need, and call Sunray, and ask to speak to Shane. Do not expect him to be able to tell you what you need or don't need, but he is very friendly, and fully knowledgeable about what Sunray does.

    For a surface grinder application, go with the hardest wheel you can get. Most folks don't realize just how much down pressure is present on a surface grinder...anything other than the hardest wheels will "cup" during use, and cause your work piece to come out with a convex.....not good!

    Finally, Sunray is a great resource for the knifemaking world, as long as you realize and understand that it's up to you to do your homework, and know EXACTLY what you want....because you will only get what you specify.

    Hey! Maybe we should take this post and make it a sticky like you suggested! :)

    Hope this has been helpful.
  11. Josh Dabney

    Josh Dabney Moderator


    Very helpful as you ALWAYS are ! Had it not been for your previous posts on other folks questions I probably wouldn't have thought of these things and ended up with a wheel that didn't work or at least not ideal for this application.

    I checked my spindle to be sure the size was 1.25" and know that without a thinner core a 2" wheel would be wider than the available threads. Figured since I was pestering you I'd ask what you went with and go with that ;)

    Backspacing had crossed my mind but do believe that a centered hub will work fine for me also.

    Order form has been forgotten, LOL. I was planning to call to place the order as you recommended but wanted to get a rough idea of the cost before calling but see now that was probably a waste of time as requesting these additional features will change the price anyway.

    On a side note- I just got the SG wired and fired up on tues and although I've had the chuck off twice and removed both the table and saddle to degrease the ways and be sure the oil passages were clean and open and generally de-grime the entire machine I threw the stone that came on it back on and ground a few forged blanks with it.

    Without dressing the stone or grinding the chuck in it's holding about .001 over a 1x4 area. I can see I'm gonna LOVE this new piece of equipment ! Combined with the height gage I ordered I believe I'll have full confidence and control of both a FLAT ricasso and a perfectly centered edge all the way to the tip.

    Thanks again for sharing your experience and knowledge ! It is appreciated

  12. EdCaffreyMS

    EdCaffreyMS Forum Owner - Moderator

    Glad to be of service! I just was hoping that I could catch you, and that you would read my response before you tried to order something online and then wind up with something you couldn't use. WHEW! :)
  13. Josh Dabney

    Josh Dabney Moderator


    Self evaluation in knifemaking is CRITICAL (IMHO)

    At this point patience is still my biggest obstacle to doing grade A knife work, LOL. I recognize the problem and I'm working on it though :)

    I'm ready to order my wheel but not in such a rush to jump the gun before hearing the advice I asked for.

    With a couple years making under my belt I stick with my original philosophy- As a newbie I think it's important to practice due diligence, do your research. and try things for yourself. In doing such I don't hesitate to ask a question when I've got one and feel that I've done my part attempting to find the answer for myself. I've gotten away from asking alot of questions on the forums due to a little experience and having a handfull of "Go To Guys" who'll answer nearly any question I may have. I do consider you one of those guys and again thank you for being so available for Q&A online.

    I know your philosophy of being a MS and see you follow through over and over and I do benefit from every post you make. I'm still kinda amazed how generous knifemakers are with their knowledge though.

    It's a great community to be a part of !

    Looking forward to getting to see you again at Blade this year and thank you in person for all the advice you've given.

    I now feel comfortable enough to place my order which Is what I really was hoping for I suppose.

    Take care, Josh
  14. EdCaffreyMS

    EdCaffreyMS Forum Owner - Moderator

    Thanks Josh!

    Sometimes I worry that I overkill stuff, and that my responses are brash.....they are not intended that way. I just want so badly to help folks AND not steer them wrong, that I get cranked up. :)

    It may sound weird to some, but teaching is such a passion to me. We had a sermon at church last week that pretty much was right on time with me, and I certainly needed it. It was titled "Successful or Significant". Like everyone else I often get caught up in the thing that success is measured by the dollar amount of knives I sell....rather than measuring it by how significant I can be to someone else, or our community as a whole. My ability to help others and the gratification I receive from doing it are the things that really do matter, and I can only hope that through helping others I can become significant to some of them along the way.
  15. Josh Dabney

    Josh Dabney Moderator


    Glad to hear that you enjoyed the sermon. I cant count the number of times an outside perspective has changed my opinion or at least left me scratching my head thinking... Why didn't I think of it like that.

    On the contrary, I especially appreciate how you answer folks questions as thoughouly as possible. I see many answers given that end with me having a 90% understanding.

    Here I go again with lack of patience, LOL. Building my conversion before having the contact wheel in hand seems like getting the cart in front of the horse but I went for it anyway taking little bits of wisdom from everyone else's builds. Maybe once it's complete I'll post a thread on it ( once we see how it works ;) ) But for now I wanted share a couple pics just because I'm so excited about it. I'm not much of a welder yet but they are functional welds. The tubing was recycled from a wine rack we never used but had in our kitchen. I got about 8 bucks in nuts and bolts, 8 in two muffler clamps, and 4 for the hinge.

    I think I'll take it apart and shoot some paint on it while waiting for the wheel which I'm going to order tomorrow.


    It's really great to get past the "thinking about it" phase of a project like this and get to the cutting, welding, building, make the final desgn choices and finish it phase.

    Being armed with all the info on ordering my wheel gave me the confidence to just go for it, and I thank you again for that !

    Josh :)
  16. Josh Dabney

    Josh Dabney Moderator


    Yet one more thank you is due here ! I re-read this thread this morning in anticipation of calling Sunray as I wanted to write down all my specs so I don't forget anything on my order.

    "Forget the order form! Figure out EXACTLY what you want/need, and call Sunray, and ask to speak to Shane. Do not expect him to be able to tell you what you need or don't need, but he is very friendly, and fully knowledgeable about what Sunray does."

    After reading this I decided to run out and double check my spindle measurements. It's still a 1.250" spindle ;) but when my spanner nut is completely tight there's MORE than 1/4" of space so I decided to have the hub part made 1/2" thick which is the same as the stone that came on the machine.

    Ordering the hub at 1/4" would've been a mistake on my part so thanks for averting that with sound advice !


    Edited to say wheel has been ordered ! Shane was very easy to work with and made the ordering process easy. :1971_dancing_dog: :thumbup1:
    Last edited: Mar 14, 2011
  17. Josh Dabney

    Josh Dabney Moderator

    I've been sidetracked for awhile now but finally getting back on the forums and out to the shop a little so I'm updating a few old threads.

    My wheel came in, fits and works perfectly :)

    The original tension spring I had was a bit light and I was getting a good bit of "belt flop/slap" that was causing a good bit of vibration but a stiffer spring solved the problem and she's running smooth as can be now.

    Shot a coat of paint on my conversion unit so even with my Frankenstien welding it doesn't look half bad, LOL

    Just thought I'd update to say alls well in my belt converted surface grinding world

    Take care and thanks again Ed, -Josh
  18. EdCaffreyMS

    EdCaffreyMS Forum Owner - Moderator

    Hi Josh!

    Glad things worked out well! The folks at SunRay will take good care of you, as long as person does their part and give then accurate information on the wheel(s) a person needs. I'll sometimes get that "belt flop" with "Y" weight belts, but it's never anything that causes issues.

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