# Cam Grinder on The Go



## Brian-in-Oz (Feb 7, 2016)

Hi all,
After completion of the Forest Edwards Radial I decided to have a go at building a cam grinder with future engine (s) in mind other than a radial. Radial engine cams can be machined on a mill.
I am not far into the project and so far have almost competed a headstock that incorporates a fully indexable (through 360deg.) chuck.
In the near future I will post some photo's that will hopefully give a better idea of where I am at.
This will probably be a bit of a slow build as I currently have a few other things on the go but nowhere near as complex as the Edwards.

Cheers all - stay tuned   :idea:


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## michael-au (Feb 7, 2016)

Will follow with interest

Michael


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## billscaramu (Feb 7, 2016)

This is a item I also would like to build. I will be following.


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## ICEpeter (Feb 7, 2016)

Hello Brian-in-Oz,
I was wondering which system you intend to use in the cam grinder you plan to build. Is it based on a master cam / swing frame cam grinder? If so, there is an excellent thread on HMEM by Joachim Steinke documenting his cam grinder: http://www.homemodelenginemachinist.com/showthread.php?t=10361

I took the liberty and copied Achims concept and build my own cam grinder based on Achims work. See attached pictures. Have some dimensional drawings / sketches available if there is interest and am willing to post them. Unfortunately, they are not CAD but drawn in pencil but cover most aspects and details of my build.

Peter J.


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## petertha (Feb 7, 2016)

IcePeter - yes, please! I for sure would like to read whatever you care to share. that looks like quite the machine. Just curious right off the bat, what kind of motor/grinding wheel rpm did you select? And is the X,Y positioning table re-purposed or also made? I'll save the other questions for your new post


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## Hopper (Feb 7, 2016)

Beautiful work indeed. I too would be interested in any more info and drawings  you can post. I am looking at making something slightly larger to grind cams for vintage motorbikes on and this look like exactly what I need.


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## michael-au (Feb 7, 2016)

ICEpeter said:


> Hello Brian-in-Oz,
> I was wondering which system you intend to use in the cam grinder you plan to build. Is it based on a master cam / swing frame cam grinder? If so, there is an excellent thread on HMEM by Joachim Steinke documenting his cam grinder: http://www.homemodelenginemachinist.com/showthread.php?t=10361
> 
> I took the liberty and copied Achims concept and build my own cam grinder based on Achims work. See attached pictures. Have some dimensional drawings / sketches available if there is interest and am willing to post them. Unfortunately, they are not CAD but drawn in pencil but cover most aspects and details of my build.
> ...




Hi PETER
Your cam grinder looks very good well made, I would be interested in seeing any draws you have, if you want to share them with others 

Thank you
Michael


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## michael-au (Feb 7, 2016)

I will also follow this cam log as well, can always learn things by seeing how other people do it

Michael


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## Brian-in-Oz (Feb 8, 2016)

Peter that cam grinder is a thing of beauty and lovely workmanship and design.
I think it should be called the Quorn of cam grinders.
Thank you for the offer of some drawings but I am far enough into making some parts that I am more or less committed to the design I have in my head.
The headstock is completed apart from engraving degrees for the indexable chuck. Once that is complete I can assemble the parts and press the bearings home and and fix the headstock to the bed. The tailstock will be next.
I will take photo's before and after assembly.
The design I have in mind is a master cam with the grinder attached to a swing frame and 4 to 1 size reduction. My aim is to keep the design as simple as possible within design constraints but with close tolerance fit of all moving and sliding parts. I have built a tool post grinder so have a bit of experience with some aspects of the design but I am a bit of a slow worker as my trade was storekeeper not a toolmaker or fitter and turner but have learned a lot from making the Edwards Radial. 

Promise some photo's soon - Cheers all - Brian   scratch.gif


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## ICEpeter (Feb 9, 2016)

Petertha,
My cam grinder comprises two separate components. One is the actual grinder which I build before the cam grinder and it is a support grinder intended for use on my Myford S7 big bore lathe. Originally, I planned to use the support grinder on the lathe to grind crankshafts for the model engines I am building. The support grinder uses dia. 5 inch wheels, either aluminum oxide or CBN wheels both with a dia. 1/2 inch spindle bore. The support grinder uses a Sherline spindle in combination with a Sherline speed adjustable DC motor. The maximum speed is 10,000 RPM which I never use. I run the aluminum oxide wheels at around 4.500 to 5,000 RPM max. and the CBN wheels at around 7,000 RPM. I took my chances with the Sherline motor not knowing what torque to expect but in actual use and considering the amount of grinding depth per pass (less than 1/2 thou) the motor does not slow noticeably in use. When I go for 1 thou depth at roughing the motor slows a bit but does not stop.

The X / Y cross table was purchased from ENCO as a damaged unit and re-worked considerably. Squared up the slide ways / milled slide ways parallel / added new gib strips / put new 2.0 MM pitch spindles in / new spindle nuts designed to be play adjustable / ball bearings for spindles / new housings for spindle bearings / new 200 division dials with 0.01 (1/2 thou) graduation.

Peter J.


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## ICEpeter (Feb 9, 2016)

Brian-in-Oz,
Thank you for your kind comments. Will follow along your cam grinder build with interest.
Your remark being a bit of a slow worker struck a note with me. I am slow as well but still manage to plow ahead, slow though. Have worked on my engines now for about ten years and finally have only two more parts to make before final assembly. So there is now light at the end of the tunnel and I look forward to maybe another 6 month or so. Heaven knows whether I am right on that.

Peter J.


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## ICEpeter (Feb 9, 2016)

Hello all,
It appears there is a bit of interest in the drawings and build of my cam grinder and, as promised, I will post the drawings and sketches / photos on HMEM in a separate thread. Don't want to hijack Brian-in-Oz's thread.

I am looking at about 45 pages of 8.5 X 11 inch pages plus pictures and may require 7 or 8 posts. Will get my stuff together ASAP and start posting. Alternatively, I would be willing to send the whole package in one shot by e-mail to anybody who would like to receive it that way, instead of downloading 8 posts from the HMEM website.

I now will leave this thread for Brian-in-Oz to continue.

Peter J.


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## Brian-in-Oz (Feb 9, 2016)

Hi all - here are some photo's of where I am at.
First photo is of headstock parts. I have not yet pressed left hand ball race into place as I still have to make an indexing pointer to line up degrees on indexable chuck and some holes will be needed to be drilled and tapped on top of the headstock. The chuck mount is tapped in six places which allows full 360deg. indexing by shifting the mount bolts in the three slots in the boss engraved in degrees.
The chuck is a Sherline 4 jaw. I chose this instead of a three jaw as I can also use this chuck on my lathe for small precision work by mounting it on a 3MT adaptor I machined with a 16TPI 3/4" thread.
The next photo is temporarily mounted headstock on bed. 
The bed the headstock mounts to via a tongue in the slot for alignment is a 40mm square aluminium extrusion used for building such things as CNC and 3D printer projects.
Hope you can follow - Cheers Brian :shrug:


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## Charles Lamont (Feb 9, 2016)

I am in the middle of building a camshaft grinder. At present I don't have photos or a useable GA drawing but I will try to sort something out in a week or two.

Mine uses a 5 : 1 scale cam template. I found the most difficult aspect of the design was to ensure that wheel wear and dressing is accommodated in a way
that preserves the correct geometry.

The wheelhead moves along the base to the right position for each cam. The camshaft, template and the reduction motor drive for them are all mounted in a basically horizontal frame above the wheel with a toothed belt drive over three pulleys. The frame rocks up and down as the cam template rides over a shoe.

The cam drive shaft has a protractor for the relative cam angles. The template rides on a curved shoe with a radius 5 times that of the wheel. Cut is put on by lowering the shoe. Different templates can be used for inlet and exhaust.

The shoe is moved up and down with a wedge under it, and the wedge is moved in and out by a micrometer feed. The wedge slope is 1-in-5. This gives a 25:1 reduction between the wedge and the actual cam, and with a 40 tpi thread on the micrometer screw, a full turn of the knob puts on one thou depth of cut. So, with 20 divisions on the dial, one div takes a tenth off the cam diameter.

The pivot bar for the rocking frame can be lowered to accomodate wheel wear. If the centre height of the bar is the same as the the topmost point of the wheel the geometry is preserved. Strictly, the shoe curvature radius also needs to be reduced to compensate.


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## Charles Lamont (Feb 9, 2016)

Brian-in-Oz said:


> The chuck mount is tapped in six places which allows full 360deg. indexing by shifting the mount bolts in the three slots in the boss engraved in degrees.



I have done the exactly the same! Well, except that I have shorter slots and 12 holes.


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## Hopper (Feb 11, 2016)

Brian, what is the that bed made from? Is it a standard aluminium extrusion of some sort?


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## Brian-in-Oz (Feb 11, 2016)

Hi Hopper - yes it is a standard aluminium extrusion available in quite a few different forms and dimensions and usually sold to people building up CNC or 3D printer type projects. I purchased a 600mm length on Ebay Aust. for $13.20 from a seller in Melbourne. I am not sure of your location but guess it is either Aust. or the UK by your spelling of aluminium (not aluminum). The same seller also has hardened and ground steel shafting and linear bearings and an assortment of mounting fixtures all reasonably priced. I will probably be using a some ground shaft and linear bearings later in the cam grinder project. 
Attached is a picture and dimensions. Hope this helps.

Cheers Brian


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## Hopper (Feb 12, 2016)

Thanks Brian. Yes, I am in Cairns.


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## Brian-in-Oz (Feb 16, 2016)

Hi all,
headstock is now finished with addition of indexing pointer and assembled.
Next job to design and machine tailstock.

Cheers Brian   :


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## Charles Lamont (Feb 22, 2016)

Here is an image of my camshaft grinder taken from Onshape. Enough of the assembly is shown to get the basic idea. It is about half built so far. I will probably add a facility to oscillate the cam over the width of the wheel.


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## barnesrickw (Feb 22, 2016)

I like that cam grinder, looks easy enough for me to use.


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## Brian-in-Oz (Mar 1, 2016)

Tailstock is now completed - images below.
Looks simple enough but was a lot more work than the headstock.
In case anyone is curious the slots in the base are for locating shims to precisely align to the headstock. 
Next step probably to start on chassis - framework.
Charles do you have any photo's of your project? I see you are taking the rocking
cam approach whereas I am using the rocking grinder. No particular reason that is just the way my mind saw it - a different method that should give the same results.

Cheers Brian     scratch.gif


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## Charles Lamont (Mar 1, 2016)

Brian-in-Oz said:


> Charles do you have any photo's of your project?


A few here. I am working on the wheelhead frame at the moment, but have put the spindle on V-blocks to show where it goes.


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## Brian-in-Oz (Mar 8, 2016)

That looks really nice Charles and lovely workmanship and a nice compact design.
My project is briefly on hold while waiting for some 10mm aluminium plate to arrive. I will be working on the rocking beam next which will incorporate the grinding head and motor mount. I should be back into gear in about a week.

Cheers Brian  :wall:


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## Brian-in-Oz (Apr 11, 2016)

Hi all - progress on the cam grinder has been slow due to so many other activities going on at the present time and this will be the case for the next five weeks or so. To keep the thread active I have added a photo on the start made on the rocking beam. The oval hole top left is where the motor to drive the grinding head mounts with the slotted hole to prove adjustment for for drive belt tension. Underneath is a linear bearing to accommodate the ground steel shaft for the rocking beam to slide along to the position required to grind a lobe. Next job is to make the grinding head which will mount adjacent to the linear bearing with adjustment to allow for grind wheel wear. Once this has been done the beam will be trimmed up and shaped considerably to remove excess metal. Not a lot to show this post will will keep adding as things go along.

Cheers Brian :shrug:


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## John S (Apr 12, 2016)

Sorry to hi-jack this thread but many years ago I owned a cam grinder. It was a full size machine but home made and based on an old capstan lathe.
It was originally made for doing cams on racing MG's to give an idea on size. Hang on. Just remembered I have a picture as I described it on another forum.






It was a rocking cam type machine as the grinding head was very heavy and it also used an inverse cam as the master cam.
The guy who built it explained that with an inverse cam the master is just a disk machined on the lathe so the base circle is easy to do.

This is the layout how it worked.







And this is how you laid a cam out.






Using inverse masters means it quite quick to cut and file a master to size.


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## Brian-in-Oz (Apr 17, 2016)

Thank's for the pic and information John.
I don't regard information placed in the post as "hi-jacking". On the contrary it provides extra information and interest to the post.

Cheers Brian Thm:


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## Brian-in-Oz (Apr 17, 2016)

Jorgo, I was unable to send a personal reply to your message. Seems to be a software glitch in the personal reply section of HMEM as it listed you as "unseen".
I would love to see some pics of your cam grinder and please feel free to post them here. Sorry to hear of the havoc from the 2013 floods. Are you in Queensland.
Cheers Brian  scratch.gif


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## Brian-in-Oz (May 23, 2016)

Sorry for the inactivity over the past few weeks. Grand kid duty and a holiday intervened but I am now back in the work shop and working on the cam grinder again. The spindle housing is complete apart from some tapped holes on the flange to mount a cover for the grinding wheel and an oiler. It will mount into slots on the rocking arm and will have some vertical adjustment for grinding wheel wear. The spindle is also finished apart from clamping washers for the grind wheel. While I am working on this section I will probably next make the motor and spindle pulleys to try and keep some continuity in my brain as I am just designing bits as I go along but I do have a rough over all picture in my head.
Anyways it keeps me off the streets and outa trouble (hopefully).
Pics attached of spindle housing and spindle.

Cheers Brian  :wall:


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## Brian-in-Oz (May 26, 2016)

I know there is nothing demanding or exciting in making a simple pulley but thought it may be of interest how I cut a keyway when I don't have any keyway broaches (yet!).What I did was sharpen a piece of HSS the same width as the key in the shaft of the spindle drive motor and mount it in a tool holder central to the centre hole in the pulley held in the lathe chuck and locked in place with the back gear. I then simply wound the cutter through the hole using the feed wheel and taking a small shaving cut of 2 thou. at a time until reaching the desired depth in this case 65 thou. It took a little while (about 25 mins.) but worked a treat and much cheaper than going out and buying a broach. The pulley is made of 6061 aluminium and using this method in steel may be a bit of an ask but without trying I don't know.
Pics of set up and end result.

Cheers Brian   :idea:


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## Charles Lamont (May 26, 2016)

Here is a recent progress shot. The wheelhead is finished, apart from a wheel guard, which I have not yet decided how to make. The cam drive is also mostly done, including the protractor for setting the relative positions of the cams. It just needs some kind of catch-plate to drive the gear on the camshaft. At the moment I am getting ready to mill the 5:1 cam templates. I am thinking about coolant, maybe air sprayed, and would welcome ideas and experiences.


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## Brian-in-Oz (Jun 10, 2016)

First your grinder is looking great Charles. It is interesting on the different design approaches with the aim of achieving the same end result. Charles what are the dimensions of your grinder and what is the longest length of cam will you be able to grind. I have been able to spend more time in the workshop lately and things are starting to come together. Main chassis frame is done and rocking beam mounted and I now have something physical in front of me which makes designing the rest easier rather than just a picture in my head. Probably the next step will be the shaft for the master cam blanks and the drive from a reduction gear motor. After that the cam follower mechanism with micrometer adjustment to control the amount of grinding cut. When everything is in place I will then look at removing surplus metal to try and make it all look a bit prettier as well as lighten it up a bit. It doesn't sound like a lot to do but will keep me amused for hours and hours. 
Some pictures below - more to come as things progress. scratch.gif


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## Charles Lamont (Jun 10, 2016)

Brian-in-Oz said:


> what are the dimensions of your grinder and what is the longest length of cam will you be able to grind.


That looks interesting. The spindle is adjustable for wheel wear on the slots in the mounting plate?

My grinder's baseboard is 16" wide by 17" deep, and it will take a camshaft up to about 9" long.


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## Brian-in-Oz (Jun 11, 2016)

Hi Charles - yes the spindle is adjustable for wheel wear of up to 1 1/2" off of the 4" dia. Your design is a bit more space efficient as my overall dimensions  are 23 1/2" wide by 19" deep .The design will accept a camshaft up to 10 1/2" long. Cheers Brian


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## johwen (Jun 12, 2016)

Hi this is John Samphier from Melbourne Australia. I am building a 4 cylinder engine and to get accurate identical timing a grinder would be most beneficial.


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## Charles Lamont (Jun 12, 2016)

This is the setup for milling a cam template without electronic aids. The clearance ramps, flanks and nose are being milled one degree at a time, using a 0.0001" DTI for precision and a 0.001" DTI to keep track of where we are. Not seen is the clip-board with a spreadsheet printout of offsets, with each of the settings (171 for the inlet cam) being ticked off as we go. An afternoon's work.


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## Charles Lamont (Jun 12, 2016)

johwen said:


> Hi this is John Samphier from Melbourne Australia. I am building a 4 cylinder engine and to get accurate identical timing a grinder would be most beneficial.


Package? There are quite a number of model cam grinders to be seen in various places on the web, but as far as I know there is no published design. They are often quite ad-hoc and tend to depend on what motors and materials are to hand.
Mine started with an ex-shower-pump motor.


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## Brian-in-Oz (Jun 13, 2016)

Charles - what RPM are you going to turn the cam at when grinding. The geared motor I have is 6 RPM at the output shaft but my thought is to speed this up to 2:1 or 3:1 for 12 or 18 RPM. The only info I have been able to dig up was a machine running at 20 RPM. What are your thoughts?
When I made the cam ring for my Forest Edwards Radial (page 3 of HMEM build forum for same) I used an incremental 1deg. 1thou at a time method to cut the lobes and hand smoothed - polished afterwards and it worked a treat. It took a while to get going in the workshop this morning as it was below freezing here last night with a heavy frost and was damned cold. We usually pay more attention to air conditioned cooling down here than heating but occasionally get caught out.
I was in the UK at friends in Suffolk in Sept. 2014 and the weather was perfect as we travelled from Scotland to Cornwall. Just lucky they kept telling us. Cheers Brian :rant:


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## Brian-in-Oz (Jun 13, 2016)

Hi John - Thanks for your interest - Charles is right about most home build cam grinders being ad hoc almost Heath Robinson type contraptions but all strive to duplicate a master cam into the actual and usually scaled down final camshaft.  I could not find any actual plans for one and embarked on the potentially risky "design it as you go" method but so far so good. Building a grinder is no where near as difficult as building an engine so perhaps you may be able to get some ideas from this forum and build one before making the cam for your 4 cyl. engine.
What engine are you building and do you have a build forum on HMEM.
Good luck with your engine - Cheers Brian Thm:


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## Charles Lamont (Jun 13, 2016)

Brian-in-Oz said:


> Charles - what RPM are you going to turn the cam at when grinding. The geared motor I have is 6 RPM at the output shaft but my thought is to speed this up to 2:1 or 3:1 for 12 or 18 RPM. The only info I have been able to dig up was a machine running at 20 RPM. What are your thoughts?


Brian, the motor shaft runs at 20 rpm. Messing with available 5mm HTD belt and pulley combinations, I settled on a 2:1 reduction so the cam does a stately 10 rpm. This seems to work very nicely with the finished templates in place, and I think 20 rpm would be fine too, but I would not want to go a lot faster than that.


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## Brian-in-Oz (Jun 13, 2016)

Thanks Charles - I too am using 5mm HTD timing pulleys (15mm wide) 24 teeth on the master cam and chuck drive. I think I will settle on 12 RPM so off to my local bearing shop tomorrow for a 48 tooth pulley for the 6 RPM geared head motor. Cheers Brian


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## johwen (Jun 13, 2016)

Congtratulations, This is quality workmanship. Love to see the plans as they maybe.


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## johwen (Jun 13, 2016)

I'm building the Westbury Sealion. I have made the camshaft with individual cams locktighted to the shaft. Made with all due care but I'm not satisfied of the overall timing accuracy. I actualy made a crankshaft grinder for the crank and that worked out well.

To drive the crank I purchased a 12 volt geared motor from Jaycar here in Australia about one inch in diameter and 12 foot pounds of torque, more than powerful enough.
Allup about $50 with battery and charger. Turns the shaft slow enough for accurate grinding. Cheers John


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## ICEpeter (Jun 13, 2016)

Charles / Brian-in-Oz,
The cam grinder I built a while ago turns the shaft with the work piece at 10 rpm with good results as far as material removal and surface finish is concerned. I figure 10 to 12 rpm should be optimal.

Peter J.


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## Blogwitch (Jun 14, 2016)

Lovely piece of engineering Peter, very well made indeed, and I am sure it will last yourself and anyone following many years of faithful service.

Unfortunately (there always is) a bit of a hiccup, it seems very complicated for the average Joe to construct for maybe only a couple of camshafts to be made.

In Strictly i/c (sadly been out of print for many years), Aug/Sept & Oct/Nov 1994 issues, there is a fairly easy to build cam grinder that could be knocked up in a few days rather than months if you have the bits knocking about, that will do the job admirably for most peoples needs.
I do have copies on PDF, but I think it might be illegal for me to post the text and plans on here because of copyright.

If anyone wants more info, send me a PM.

John


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## Brian-in-Oz (Jun 14, 2016)

Thanks for your input Peter - have decided to start with 12RPM and trust that will be OK. I hope to get a bit more done later in the week.


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## ICEpeter (Jun 14, 2016)

Hello John / Blogwitch,
Thanks for your kind remarks. You are right, my cam grinder is complex but it serves other purposes as well besides cam shaft grinding. It allows multi cam camshafts of up to 225 MM (9 inch) to be ground and also allows the grinding of crankshafts with a throw of up to 32 MM ( 1 1/4 inch) as well as cylindrical grinding of up to 50 MM (2 inch) by 225 MM (9 inch) long pieces. Short pieces of dia. 100 MM (4 inch) by 50 MM (2 inch) long can also be ground as well as individual cams of various diameter and length. Have used it in the past to accomplish all the previously described operations and am quite happy with the results. 
I agree its complex and it was not a matter of days for construction, more like 2 - 3 months to build. But what the heck, what is time when you are having fun building.

Peter J.


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## Blogwitch (Jun 15, 2016)

Peter,

I wasn't criticizing you or your work at all, you have done a wonderful job, and like everything else, each to his own.

All I was trying to do was to maybe dispel a few fears that to make a camshaft grinder doesn't take months of work and large amounts of pocket money, and if someone can build an engine, they should be able to construct an easy to make cam grinder to put into their engine.

I was actually going to make one, but found that I could make my cams to an acceptable standard using ETW's methods to cut the flanks on a lathe, it did the job to a standard that was acceptable to myself.
The only problem with ETW's method is that you harden after machining rather than before with a cam grinder, and things can sometimes not go quite right..

John


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## Brian-in-Oz (Jun 30, 2016)

Hi all - cam grinder is coming along nicely. About the only things left to make are the master cam follower (tomorrows job), a locating keyway on the master cam shaft, positioning collars for the rocking arm linear bearing, a terminal switch box for the motors,a guard for the grinding wheel and a bit of cosmetic tidying up. At the moment it is mostly in bits so a photo not available at this stage (soon) but have attached a pic. of the micrometer stop for lowering the rocking arm as grinding a cam progresses.
Making this was an interesting exercise in its own right and I am quite pleased with the end result. It is made to the Imperial standard 40tpi with 25 one degree increments per revolution.The travelling "nut" with an internal 40tpi cut on the lathe to specs. was made to a firm finger push fit into the cylinder and then lapped with some 600 valve paste I bought to lap the valves in the Edwards Radial so it is a nice smooth sliding fit with no play. The next challenge was to cut the 40tpi thread to fit the "nut" so that it turned smoothly with no backlash so lapping paste to the rescue again. I made tiny final cuts until the "nut" screwed on hand tight and then lapped the thread by spinning back and forth on the lathe
by reversing direction and the whole device spins as smooth as my Starret without any backlash. 
Of course lowering the beam say 12 thou. will lower the grinding wheel only 3 thou. because of the 4 to 1 reduction ratio. I think making a conventional outside micrometer would be a nice personal satisfaction engineering project but from a practical point of view a bit pointless.

I will follow up with some more pics. soon- Cheers Brian


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## Brian-in-Oz (Jul 3, 2016)

This is the master cam follower. It attaches to a sliding vertical adjuster. The relief  on the LHS is to provide clearance from a rear chassis cross rail in case it is ever needed to grind a large cam. Apparently a flat follower would work OK but I decided to grind the optimum 4 x the radius of the grinding wheel in this case 20 cm. on the contact sole.

Cheers Brian ;D


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## Brian-in-Oz (Jul 5, 2016)

Hi all - here's some pictures of where I am at. Not a lot to do but still some hours for me. I want to give a bit more downwards adjustment of the spindle to accommodate grinding wheel wear, slot the master cam drive shaft to keep master cam calibrated, a grinding wheel guard, grinding wheel dresser attachment and wire the motors with switches. The weather has been cold and wet so a good inducement to stay in the workshop.

Cheers Brian   scratch.gif


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## Brian-in-Oz (Jul 27, 2016)

Hi all At HMEM -  my design it as you go cam grinder is now complete.
It has been an interesting exercise in coming up with design solutions for each step as the project progressed. In an attempt to ensure that the contraption might actually work when completed I have incorporated as much adjustment as possible to the components . i.e vertical movement on the spindle to accomadate grinding wheel wear - chuck calibrated 360 deg. for timing cam lobes - master cam drive shaft adjustable to "lock in" any required settings for cam being ground - cam follower adjustable an well as adjustment on the cam follower mount - micrometer adjustment in .001 inch to lower rocking beam as cam lobe grinding progresses - because of the 4 to 1 reduction ratio of the beam a 4 thou. adjustment at the micrometer calculates to a grinding "cut" of 1 thou. -
rocking beam adjusts laterally on a linear bearing on a hardened ground shaft to move from one lobe to another and is locked in place while grinding with a collar with grub screw on each side of the linear bearing - micrometer slides and locks into position as each lobe is being ground. The cam being ground rotates at 12 RPM and the grinding wheel at 6000 RPM and rotating in opposite directions. A camshaft up to 11" long can be accomadated and the maximum lobe rise from centre is .600". (maybe if this thing works at all I can recoup a few bucks grinding hot cams for the motorcycle "cafe racer sect" - only joking!).
I also need to put together a diamond wheel dresser but this is relatively simple and should not take long.
At this stage I have not decided what the next engine project will be but am leaning a bit towards a flat four or six. Unfortunately this will be postponed a bit into the future as SWMBO has presented a daunting list of household jobs.
I will however try to sneak in a test cam grind and some pics in the near future.
Below are some pics of my "Heath Robinson Contraption" and if it actually works and grinds a nice cam only then can it be called a CAM GRINDER.

Cheers Brian     -       :hDe:


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## Charles Lamont (Aug 12, 2016)

Looking good.


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## Charles Lamont (Oct 16, 2016)

I think wacky machining setups are always worth a photo and a post. Here we are milling the 12.3" radius on the delrin cam template follower shoe. This radius (5 times that of the grinding wheel) is needed to maintain the correct cam profile, and makes a visible difference to the smooth action of the machine. The setup looks horrible but actually it went better than I expected, just needing steady hands on the rotary table handwheel to get a satisfactory finish.


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## Brian-in-Oz (Oct 17, 2016)

Hi Charles,
I did an almost identical setup for my master cam follower except that I used 1/2" steel plates for the jig and ground the follower on a flat bed grinder by rocking the pivoted top plate holding the follower to and fro giving a typically nice ground finish. I have not yet tried to grind a test lobe as I have been sidetracked with other activities but should get to it soon. When I do I will post some photo's.
Cheers Brian.


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## Brian-in-Oz (Nov 30, 2016)

Hi all - well I finally got around to see if my cam grinder would work and all looks promising. I made a master cam from aluminium (just a made up profile for test purposes) and ground a 1/4 size cam from mild steel. Now that I know that it works I will do some tinkering around the edges to try and make it a more complete package. The micrometer adjustment for feeding the grinding wheel worked fine but I also think adding a micrometer adjustment to the cam follower would be a worthwhile addition as it would allow grinding the cam a tiny bit oversize and then finish with a final grind to exact size. This would also be useful
in compensating for any grinding wheel wear that occurred when grinding a lobe.
A coolant spray could also be a worthwhile addition at the expense of making the grinding process a deal messier. I will post improvements - additions as things progress and start looking for plans for an engine with as many cams as possible.
I may also post a movie of it working in the future. Some photo's below. Cam is 1/2" base to nose.

Cheers Brian   woohoo1


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## gbritnell (Dec 1, 2016)

Hi Brian,
The cam lobe looks great. Congrats on a fine piece of home engineering. 
gbritnell


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## Shipdisturber (Dec 11, 2016)

Right on Brian beautiful job looks very professional. Thanks for getting my mind working I have already dreamed up a simpler machine so when the time comes I'll post my work.


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## Brian-in-Oz (Dec 19, 2016)

Hi George and Shipdisturber. Thank you for your kind words of support.I am still tinkering around the edges and have added a micrometer adjustment to the cam follower to accurately dial in finishing dimensions of the cam lobe. This addition while not absolutely essential should add to ease of use. (I just don't seem to be able to leave well enough alone and keep adding incremental improvements).
I will add a photo ASAP. Looking forward to your post and see what you come up with Shipdisturber. This must be one of the best "Heath Robinson" projects to tackle.

Cheers Brian


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## Brian-in-Oz (Dec 20, 2016)

Hi all - here are the photo's of the adjuster I have added to the cam follower.
It is graduated in imperial so that four increments on the dial will move the grinding head 1 thou". The adjuster on the left lowers the rocking arm with the cam follower adjuster locked in place after initial setup until the lobe grind is complete. By grinding the lobe slightly oversize it can be measured with a micrometer and the finishing grind to size easily and accurately dialled in with the cam follower adjuster.
Enjoy the photo's.

Cheers Brian -  and a very Merry Christmas and a safe, happy and prosperous New Year to all and may Santa bring each and every one of you a new CNC Mill.*beer*


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## Charles Lamont (Feb 11, 2017)

The cam grinder is finished and has sucessfully ground a camshaft for the Westbury 'Seagull'. When I say finished, I have not yet built the bit to oscillate the rocking frame side-to-side over the width of the wheel. I just moved it slowly by hand instead. It needs doing, as I had a overshoot and one side of the adjacent cam is no-longer quite perfect. Overshoot too far and the cam template could fall off the side of its shoe.

The pictures actually show things after I had finished the job and cleaned up. I did not want to mess about with photography while I was trying to concentrate on making cams.

In practice the areas behind and below the workpiece would be stuffed with kitchen paper to collect the overspray of coolant, which went everywhere except out through the wheelguard drain pipe. I found I had to put a pretty tight squeeze on the liquid pick-up pipe to reduce the flow enough to just keep the job wet, even with the air tap little more than cracked open.

A minor annoyance is that there is really no way to get a mic across the cam in situ. The shaft has to be removed for measurement. On the other hand, it does help prevent getting grit in the micrometer.

Additional bits not shown are a block for mounting a wheel dresser on the 'tailstock', a height gauge to transfer the height of the top of the wheel to the pivot bar (a requirement for preserving the correct geometry), and a synchronising gauge for the setting the cam template and the camshaft 'catch-plate' in phase.


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## dsage (Feb 11, 2017)

Will you be checking your finished cams against the expected profile? I find a good way is to mount an indicator vertically in the quill of your mill with a home made tip the same size as the lifter you expect to use (important). 
  Then mount the cam under the quill in a rotary table so it lifts the indicator. Use the rotary to measure the degrees of rotation and plot against lift as measured on the indicator. I'd be interested to know if you get the cam profile you expected i.e. - valve opening and closing points, lift, duration, fluctuations on the profile etc. etc.

Let us know what you find.

Thanks

Sage


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## Charles Lamont (Feb 12, 2017)

dsage said:


> Will you be checking your finished cams against the expected profile?



No. I am satisfied that I made the templates to the correct profile, and that, when set up correctly, the geometry of the grinder correctly reproduces that profile.


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## Shipdisturber (Feb 13, 2017)

Beautiful setup great workmanship.


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## Brian-in-Oz (Feb 20, 2017)

Nice to see your grinder up and running and grinding some lumps for your "Seagull". Have you or are going to have a build thread for this engine? I am currently procrastinating on my next build and tossing around ideas as diverse as a 14 cylinder radial to a single cylinder with rotary valve but neither of these two use a conventional camshaft so I will probably settle on something with a conventional cam so the cam grinder can be put to use. Sorry for being a bit slow in responding but I have just got back from NZ after escorting my sons German in laws on a holiday of both islands. Helps that us Aussies and the Kiwi's sort of speak a similar language.
Cheers and keep up the good work - Brian :thumbup:


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## Charles Lamont (Feb 20, 2017)

Brian, I am not doing a thread here, but at:

http://www.charleslamont.me.uk/Seagull/home.html

although at the moment I have only written up as far as April 2015.


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