Universal Grinder Fine Feed Adjuster

One of the limitations on my tool and cutter (plus surface) grinder was the coarse vertical feed on the motor carriage. I came up with an approach that still allows fast vertical traverse but also allows a very fine down feed for the grinder. It took a bit longer to make than I thought it would but it was worth the effort.

Based on a simple ramp and using a 5/16-18 piece of all thread, one steel ramp and one brass ramp and aluminum for the housing. It has about .250" travel up or down. The screw moves the ramp by one inch to move the height .250" so it is very fine. Positioning is just by sliding it up or down until the adjuster contacts the motor mount and then locking the brass locking knob. The 1/2-10 original lead screw "floats" in its lower mounting block so when I need the fineness I simply run the adjuster up to the bottom of the grinder mount and back off the 1/2-10 lead screw. Gravity and the brass knob on the left side do the adjusting. The carriage has separate aluminum knobs that lock it in place once the desired height is reached.

Cheers, JR

Here is a link to the tool and cutter grinder:
http://www.homemadetools.net/forum/s...9982#post71647

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Thanks jjr2001! We've added your Grinder Fine Feed Adjuster to our Grinding category,
as well as to your builder page: jjr2001's Homemade Tools. Your receipt:

<div id="blocks"> <div class="block b1 pngfix"> <div class="bimg"> <div> <a href="http://www.homemadetools.net/homemade-grinder-fine-feed-adjuster"> <img src="/uploads/156453/homemade-grinder-fine-feed-adjuster.jpeg"/> </a> </div> </div> <div class="head pngfix"></div> <div class="left pngfix"></div> <div class="right pngfix"></div> <div class="blockover b1 pngfix"> <div class="title"> <a href="http://www.homemadetools.net/homemade-grinder-fine-feed-adjuster">Grinder Fine Feed Adjuster</a> <span> by <a href="http://www.homemadetools.net/builder/jjr2001">jjr2001</a></span> </div> <div class="tags">tags: <a href='http://www.homemadetools.net/tag/grinder'>grinder</a>, <a href='http://www.homemadetools.net/tag/adjustable'>adjustable</a> </div> </div> </div> </div>
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Very cool, JR:

i picked up an old DuMore toolpost grinder a while back and wondered how to build a suitable feed for it: great work, sir.

Thanks rebuilder,
Please post some pictures of your completed unit when you "get er done"

Cheers, JR

Hi,
Really a good idea, it can give very precise adjustments with a minimum of calculation, but only if you don't forget the geometry lessons when young at school…:lol:

Good point.

So far I just need it to adjust in a very fine increments and it does that quite well. I just ground a 1" ball form a ball bearing and made it flat on one side. Actually needed to turn it almost 1/4 turn for each pass with the grinder. If I need to know a specific amount of travel I will probably cheat and just measure total travel and calibrate the knob to that. I need to engrave something anyhow, just for fun..

Cheers, JR

Muy original el sistema, trataré de hacer algo parecido en mi cortadora de cerámicos, :aplausos:

Quote:

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Originally Posted by jotasierra

Muy original el sistema, trataré de hacer algo parecido en mi cortadora de cerámicos, :aplausos:

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Thank You, JR

Congratulations jjr2001 - your Grinder Fine Feed Adjuster is the Tool of the Week!

This was a huge week for homemade tools, and we had to cull down the best entries in several rounds. Your Grinder Fine Feed Adjuster, made for your previously-posted cutter grinder, really stood out. Congratulations also on the huge volume of tools you've been submitting. You're up to 34 homemade tools already, and have reached position #33 on our list of most prolific tool builders.

We also had a nice Backhoe Bucket Quick Disconnect from Frank S, a Drill Press from Grale, a clever Chuck Jaw Truing Tool from olderdan, a Straight Knurling Tool from rossbotics, and very accurate Quick Change Tool Holders from Metaler.


You'll be receiving one of our official HomemadeTools.net T-shirts:

https://s3-us-west-1.amazonaws.com/h...mt-tshirts.png

Please PM me a mailing address, black/white color choice, and size preference, and I'll get it mailed out shortly.

And, we've added the wrench-on-pedestal award to the awards showcase in your postbit, visible beneath your username:
https://www.homemadetools.net/forum/...eWeekIcon4.png

You're our 101st Tool of the Week winner. :hattip: All previous winners can be viewed here: https://www.homemadetools.net/forum/...0595#post72779

Congrats again and nice work!

Hi JR
The finish you have on the anvil is quite acceptable, what is your motor speed and grinding wheel spec?

Cheers MM

This is a very nice surprise. Thank you Jon.

Homemadetools.net has become my favorite internet resource. I have been reading it for a few years now and just decided to post a few of my own shop made tools. I find ideas for tools that I need and even ones that I don't need but would be nice to have. It is funny but I started out with this machining hobby to make parts for my model airplane hobby and maybe a steam engine model. So far I have made a lot more tools for the shop than parts for the airplanes! I do have one airplane which is the F4 in my avatar for this site. All of the parts for the F4 were CNC cut with my CNC Router way before the Mini lathe and Mini Mill arrived in my shop. Matter of fact my airplane hobby is taking a way back second seat to machining!

Thanks again, John

Quote:

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Originally Posted by Meldonmech

Hi JR
The finish you have on the anvil is quite acceptable, what is your motor speed and grinding wheel spec?

Cheers MM

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Thank you Sir, I am just running a "standard" coarse wheel that came with the grinder. It is a 3450 rpm motor. The finish has improved since I added the fine feed adjuster.

Thanks again, John

Quote:

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Originally Posted by jjr2001

This is a very nice surprise. Thank you Jon.

Homemadetools.net has become my favorite internet resource. I have been reading it for a few years now and just decided to post a few of my own shop made tools. I find ideas for tools that I need and even ones that I don't need but would be nice to have. It is funny but I started out with this machining hobby to make parts for my model airplane hobby and maybe a steam engine model. So far I have made a lot more tools for the shop than parts for the airplanes! I do have one airplane which is the F4 in my avatar for this site. All of the parts for the F4 were CNC cut with my CNC Router way before the Mini lathe and Mini Mill arrived in my shop. Matter of fact my airplane hobby is taking a way back second seat to machining!

Thanks again, John

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Congratulations John, Well deserved! I have to say you have Prolifically contributed some great stuff in a short time. Thank you for sharing all of it with us!! Welcome to the world of making tools to make tools then to make stuff! :lol: The idea of using a ramp for fine adjust is great and simple to do and using a DTI for movement is always simple. Actually its funny because I came up with similar solution (a double wedge) recently for moving a motor with worm to a spur gear for a music box I'm building for my grand son. I had tried to build a gear box but because of the gear ratios (30:1) it was almost impossible to turn the crank by hand also without disengaging the motor, which wasn't a pretty prospect. It'll be solar powered or hand crank.

Was wondering about that F4 in your avatar...is it RC? Used to do U-control a hundred years a go...AMA "A" Rat Race, Stunt, etc. but did pick up an RC Quad Copter Car a while back for my son, G-son and I to play around with. My son and I did rockets for several years too when he was around 10. His teacher ask us to do a demo for the class so he built a Foxfire and I built an SR71....they loved it and we did too.

Thanks for all the great posts and contributions! ~PJ

Thanks PJ,
The F4 is indeed RC. It sports a 90mm EDF and is powered by a 6S 5000mah battery. I built that one from scratch using parts made with my CNC Router. My son got me back into RC in about 2006. Funny thing is I am still flying them and he is a bit busy with life at this time but I am sure he will be back to the hobby.

I added an engraved knob to my fine feed assembly. It worked out nice since 10 rotations moved the wedge exactly .100". The knob has .001 major graduations and .0005 sub divisions so it is plenty fine for the machine.

Cheers, JR

FELICITACIONES JJR, los esfuerzos y la inventiva se premian y más se premia cuando no hay intereses mezquinos y se comparte todo en bien común como es por lo visto la actitud general del foro, gracias por compartir y que sirva de ejemplo a todos aquellos que ingresan en este sitio.:Pulgares hacia arriba::aplausos::martini:

Thank you jotasierra
I started making tools to make parts for my models and now I seem to make more tools than models....

Cheers, John

I added graduations for my fine feed adjuster knob. The long lines are .001" vertical movement and the short lines will move the grinder by .0005". Works good for what I need right now. I still need to work on overall accuracy and I would like to improve the finish of the grind.

Cheers, JR

Looks Real good JR...should be close enough for sure. Nice knurls too.

On the other RC note, how much thrust do those EDF's usually generate? The 6s 90mm one that I looked at was about 3kg and the motor/fans are a half kilo...wouldn't think you'd have much flight time on 5A...don't know much about them but pricey little beggars. 90mm is pretty good size for an RC. Thrust to weight I do know a bit about. Don't mean to hijack your fine build thread...just curious.

Thanks again for sharing your builds with us and please keep up the great work! ~PJ

Hi PJs,
The EDF in my F4 is pulling about 1500 watts and about 5 lbs thrust. You get about enough time to go around the field 3 times and land! If you are up longer than that she will dead stick and you don't have much left to take home! My F4 is not 1:1 thrust and weights about 7 lbs. There are EDF jets that are pushing 25 lbs and more and like all good EDF jets they get 3 to 4 minutes of flight time. Limiting factor for me is the battery temperature. I do not like to see them hot. Some will push them over 120 degrees and that is really hard on the lipo. I do not fly the F4 in the summer at all.

My power system is a bit old and the efficiency would be better with one of the newer systems. Don't fly this one too much as the edf jets are a handful. I prefer the pattern style prop jobs and fly a home brew Ms. Norway. Built from RCM plans. I can get about 6 minutes of really good flying with that one.


Really enjoy having the grinder in the shop.

Cheers, JR

Quote:

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Originally Posted by Okapi

Hi,
Really a good idea, it can give very precise adjustments with a minimum of calculation, but only if you don't forget the geometry lessons when young at school…:lol:

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All that math is alright if that is the way you do it. I would put a mark on the face of the knob with a marker and a DTI, make one revolution of knob, then figure out how many lines you would like to put on the dial. If one rev is .0010 then 10 lines would be .0001 per line. No math to error.
Nelson

Hello ncollar, Actually the knob is graduated. Post 17 shows the knob detail with the long lines being .001 and the half lines being .0005.
It does not show up that well in the thumbnail but if the thumb nail is clicked to large size the graduations shows up.
No calculations required.

Thanks for checking in.

Cheers, JR

Quote:

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Originally Posted by ncollar

All that math is alright if that is the way you do it. I would put a mark on the face of the knob with a marker and a DTI, make one revolution of knob, then figure out how many lines you would like to put on the dial. If one rev is .0010 then 10 lines would be .0001 per line. No math to error.
Nelson

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The problem with that approach is that if you want one full revolution to be some "nice" number (e.g. 0.010) rather than some inconvenient increment, you must take account of the mathematics of the design. (Besides, you'll never learn any math if you avoid opportunities to use it in practical problems.)

The brass wedge will rise by:

P * tan(A)

for every revolution of the screw driving the steel wedge. Here

P = screw pitch = 1/tpi
A = wedge angle

Let H = desired rise for every revolution of adjusting screw. Then we can solve for the required wedge angle...

H = P * tan(A)

A = arctan (H/P)

As an example, for ten thousandths rise per revolution of an 18 tpi screw, we have...

H = 0.010
P = 1/18

A = arctan (0.18) = 10.2 deg

Marv
Math and history was my best subjects in school. I forgot so much of that it would be like going back to school, but once you learn to ride a bicycle you never forget how to. I guess I just do it the easiest way to me, the KISS theory.
Merry Christmas
Nelson

Thanks for the detailed math explanation to the problem Marv. I can use that on my next wedge lift system.

I must admit that I used the DTI method to get a "close" solution. I just looked at my setup and found that
I have a .001" error in a full turn of the knob. One line is close to .001 but just a bit short. I usually work to .001"
for most of my builds and that is more than I usually need..However I always spend considerable time
fitting up the parts. So time could be saved with using the proper math for the solution.

Thanks again and Cheers, JR