New Mark VII owner in need of repair help.

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rkmhd
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Joined: Sun Jan 16, 2011 4:25 pm

New Mark VII owner in need of repair help.

Post by rkmhd »

Hello all.

I picked up a mark VII a few months ago. Little did I know what I was getting into. It worked at the previous Owners house. I tried to use it at home and it would hum and not turn. So I took the headstock off. and took it appart. The belt was stuck in the shelve. So I took the belt off and ended up getting a new one. Then I took the motor appart because the wires were literally falling appart. I nipped them back and soldered in new wire with some shrink wrap. Everything seems to work pretty good. The unit does get quite loud at full RPM, and I noticed the speed selector turns on its own a little. For the most part I fixed that issue. The latest is the gearing that moves the headstock up and down. I don't quite understand what needs to be fixed on it. I can move the gear forward on the shaft to connect with the drive gear of the handle. It stayes there as long as the headstock is going down. As soon as I rotate it to go upwards. The gear slides out of place and it just sits there. Can anyone shead some light on this please. I am in the middle of uploading some pictures of the gear to see if it makes any since to any of you guys.

Thanks,
rkmhd
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Post by rkmhd »

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JPG
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Post by JPG »

1) Congratulations on getting a Mark VII with both the gearing and the speed control cam 'not broke'. Take very good care of 'them'.

2) Make sure you lubricate the control sheave asap and often thereafter. Ditto the floating sheave.

3) IIRC the 'crank' is pulled out/pushed in to lock the headstock/carriage and the opposite to allow adjusting. I do not have one of these so I cannot verify which way it locks, and whichway it adjusts.(see below)

4) Not sure what you meant by 'up/down', but I would restrict experimentation to determine how it is supposed to work with it 'horizontal'.

OK I went into my 'library' and discovered the following: The crank lever flips 180 between lock and adjust mode. There is a smooth and a rough side to the lever handle so you can tell which way it is positioned(necessary since it also cranks)(rotates).
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Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10
E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
e.friedl
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A Little more about the gears

Post by e.friedl »

I've only had a Mark VII since this summer and perhaps my response is not relevant but... In the photos there is the gear that moves along the rack to make the head transit along the way tubes. Directly below that gear is a second gear that can be slid up and down relative to the first gear. In one position it will allow the crank to drive the headstock. In the other it will be disengaged and the headstock will move without the use of the crank. Perhaps this is part of the problem?????
Ed
damagi
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Post by damagi »

If you need any parts - PM me. I took apart a headstock and probably have what you need.

I also have a parts list and owners manual that I can scan if you need them.
Mark 7, Pro Planer, Jointer, Bandsaw w/Kreg, Biscuit Joiner, Belt Sander, Jig Saw, Ringmaster, DC3300, Overarm Pin Router, Incra Ultimate setup

JWBS-14 w/6" riser, RBI Hawk 226 Ultra, Bosch GSM12SD Axial Glide Dual Compound Miter Saw

-- I have parts/SPTs available, so if you are in the Seattle area and need something let me know --
damagi AT gmail DOT com
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JPG
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Post by JPG »

By comparing your pix with the drawings in a Mark VII manual, I have arrived at these conclusions.

The crank when 'flipped' so the knob is pointed towards the headstock engages the wedge locks against the way tubes.

When flipped out so the knob is facing the 'operator' rotating the crank rotates a worm gear that rotates the bevel gear shown in your pix.

The pinion gear above the bevel gear in your pix is what moves the headstock by meshing with the rack on the way tube.

When the disk below the bevel gear is 'up' two pins connect the bevel gear to the pinion gear. When the disk is pulled 'down' the pins retract from the pinion gear and the pinion gear is 'free wheeling'.

I believe the shaft that the gears above are mounted on has become loose and dropped down so the worm gear has not been engaging the bevel gear properly. Abnormal wear of the top of the bevel gear is evident in your pix.

If I understand the parts diagram correctly, that shaft is screwed into a boss on the underside of the headstock casting.

Hopefully the boss is not broken, and securing the shaft will raise the parts to their proper location and the 'abnormal' wear will no longer be causing malfunctions.:)

My reference to the gear as a bevel gear is because the teeth are skewed. Actually it is a half of a worm gear set and I believe the face is concave. You may need a new one - see the post#5!!!!
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╟JPG ╢
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Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10
E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
rkmhd
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Post by rkmhd »

Thanks guys. I'll give that a look at for sure. I did lube the sheves when I had it all appart.

The gear in the picture that moves back and forth is definately worn a little. Now the plastic gear along the headstock pole is in great condition.

I have been working on the Cam speed selector a little. For some reason at medium speed it would rotate its self faster and faster until it was almost at full speed. I had to make a washer to put behind the C clip that holds the selector on to take up slack that was alowing the selector to loose tension on the selector berings that lock each speed.

I would love a PDF of the unit ryankmiller@comcast.net
rkmhd
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Post by rkmhd »

I just got done checking it out. The shaft the chewed up gear is on is not removable. It is pressed and glued into place. It does have a removable c-clip on the end with the gear. So it looks like I can replace it as long as I can get the needed gear.
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JPG
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Post by JPG »

rkmhd wrote:I just got done checking it out. The shaft the chewed up gear is on is not removable. It is pressed and glued into place. It does have a removable c-clip on the end with the gear. So it looks like I can replace it as long as I can get the needed gear.

Glued?????????????? Sounds like a botched repair attempt!

P.S. I believe the gear getting chewed up on the top was due to the gear being too low relative to the worm gear. If that is not corrected the gears will still not mesh correctly.
╔═══╗
╟JPG ╢
╚═══╝

Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10
E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
rkmhd
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Posts: 9
Joined: Sun Jan 16, 2011 4:25 pm

Post by rkmhd »

It looked like a glue... I scraped it with a screwdriver. It turned out to be some old dust mixed with some grease, and belt dust from over the years.

I just don't see how it can be adjusted any at all. I must be missing something. With the gear all the way pack you can see it sits perfectly where the gear is missing/worn away. If there was a new gear to replace it with there wouldn't be much gear bite to work the stock up and down the track.
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