Schedule a Meeting · Talk to a real woodworker: +1 937-890-5197 · 8:00AM – 4:30PM ET

Mark VII “Project Machine”

shipwright

The spring is not weak.

By “fully wound” I just meant that I had loaded the spring before installing the quill.

I don’t think it’s the spring. It is hard(ish) to push together and pull apart in my hands. I can feel the pressure and vacuum suction.

It’s weird.

Do you think drilling a couple of small holes in the plastic spline receiver would significantly weaken it? Is it a Mark V part that I can replace?

JPG

I think one small hole(<1/16") will prove the theory and not diminish strength. I believe compatible with all other versions of the nylon coupler.

Question is where? :D

shipwright

That’s a relief. Today I’m going to try the quill return without the main shaft in place to make sure it isn’t friction in the sliding area of the quill. If it isn’t that I’ll try a small hole and see if that helps. I’ll also try some dry lube spray.

Wish me luck. 😁

shipwright

I’m thinking about the red arrow for the first try. What do you think of trying where the blue arrow is?

JPG

Blue, no. If it is the coupler that is creating the 'vacuum' the red location is more likely to succeed. That is as long as it coincides with the transition between quill spline and drive sleeve spline.

How some ever, the trapped air is likely in the drive sleeve. But the splines should allow air to escape.

I think we need to be sure just where the trapped air is.

But like you said it may be spline drag.

shipwright

I cleaned a dry lubed everything and drilled one 7/64” hole in the coupler. I also flipped the cupped washer in the quill feed. (The diagram in the manual disagrees with you about that) it moved a little better but still did not retract well. I decided to move on and finally got it running. With the vibration of the motor running, or the rotation of the shafts perhaps, it retracted just fine. I didn’t get much time to play with it as it was the end of the day but tomorrow I should be able to clean up the details and have a better picture of what I have.

JPG

Yes I was influenced by the M5 positioning of the cup washer. Thank You for catching that! That shifts the quill shaft out towards the stop end.

I do question it's accuracy as the cupped washer provides the transition between the sliding sleeve and the web.

shipwright

To be honest I don’t think it made any difference but who knows.

JPG

mvii quill.jpg

Gotta say 'my way' makes more sense.

shipwright

I can’t disagree but I thought if I was looking for a problem I should try the “book version”.

Like I said, doesn’t seem to make any difference.

JPG

May not fix 'your' problem, but I think it needs to be as pix above.

shipwright

Next time I’m in that part of the machine I’ll revisit that.

For now, I have everything back together and the motor no longer insists on blowing breakers.

….. however …… I have a few speed changer related issues. (I am at this point working with a “repaired” cam)

1) when the dial goes past about the stated “saw” speed moving up, the inner sheave half on the idler shaft comes off the key in the shaft. Am I missing a spacer behind the tube the follower bearing seats in?

2) there seems to be excessive vibration of the follower but the bearing seems okay to look at and wiggle.

3) in one direction the speed dial holds the speed (in the limited range I can play in with this cam) but in the other direction it wants to run away to high speed. (Can’t remember which)

4) the follower seems quite rough. I would have expected a very smooth surface with rounded edges. It actually seems to be trying to dig into the cam. Could this be a “home made” part?

My new printed cam should arrive soon so I will have more range to play with but something seems un-right in the setup besides just that.

JPG

1) By 'inner' sheave I assume that is the 'control' sheave? If it slips off the key, I think the key is short.

3) Creeping towards fast is caused by insufficient spring tension on the two bullet shaped 'detents'.

4) Is the follower correctly installed. It is NOT symmetrical. Backwards it tends to interfere with the cam. The roll pins may be dragging on the inner surface of the outer cam surface or they may be extending too far.

May help? https://forum.shopsmith.com/viewtopic.php?p=140242#p140242

P.S. Realize the follower will shift(in/out) with different positioning of the eccentric(for poly-v belt tension). That must be provided for by adequate clearance between the pins and the cam.

shipwright

1) pretty sure the key goes all the way to the end but I’ll check. The sheave doesn’t fall off so it must be short.

3) creeping to fast (and it’s hardly “creeping”) is only in one direction and I think it’s a symptom of a bigger problem, perhaps related to the question I have for you at the end of the post

4) I’ve been all over that thread and made and found all the mistakes. ….. I think. The control shaft seems too short to have the eccentric gap at the 3:00 side so I’m pretty sure it needs to be on the 9:00 side (as you show it). I also had the follower upside down but it’s fixed now. Aside from checking the key length again (and if it is trapped or can move……) I don’t think there is much I can do until I have a better cam.

Now for the question.

I hate leftovers! Can you tell me where this goes? Is it in the whirring bits or the tightening and adjusting bits? There are only a few in the headstock and they are mostly other sizes. Can’t for the life of me remember where this one came from.

shipwright

State of the Project:

JPG

MAYBE HERE?

QUILL RETAINER.jpg

Since the MVII runs both directions the M5 MANTRA towards 9:00 becomes moot. However I think the cam follower offset assumes the same direction.

shipwright

Damn! I’m pretty sure you’re right. I don’t remember putting one there. I was hoping it might be a factor in my vibration.

Thanks, easy fix.

shipwright

Found this in my pictures. Is this short enough to be trouble?

…and should the key way in the floating sheave be wider than the key? Mine is. It’s not worn, clean cut but wider than the key.

JPG

Key and keyway 1/8"??? Control sheave keyway slop NOT desirable and causes noise and potential jamming. I do not think your length is an issue.

shipwright

Could I have a sheave half that doesn’t belong to this machine?

« Previous Page Next Page »