Magna 610 Jigsaw Lower Chuck Assembly Issue

[popjack]

Bought an old Magna 610 18" jigsaw (with the large aluminum "C" arm) some time ago and learned after purchase that I was sold a unit with some missing parts ( lower guide post assembly creating tension on the blade beneath the table). I purchased some spare parts and attempted to install the blade guide assembly , but the fiber rod hits the lower chuck assembly when the jigsaw shaft is rotated.

With the newly purchased blade guide installed, the lower blade chuck assembly always hits the fiber rod in the blade guide since the height of the lower blade chuck cannot be extended with the unit properly affixed to the housing. Also the threads of the blade guide are insufficient,even at that height to secure the blade guide to the jigsaw housing and bearing assembly case.

Has anyone ever seen this before? Is there an adjustment on the jigsaw which decreases the travel action of the lower chuck assembly preventing the assembly from extending to such a height beneath the table and hitting the fiber rod in the jigsaw lower guide post? Or have I purchased a unit which is beyond help? All other parts work fine, but the stability of the jigsaw blade is not the best since the fiber rod in the lower guide post cannot be adjusted without the lower chuck hitting it.

Any thoughts, or assistance with this would be greatly appreciated. Thanks again in advance ---- popjack

[JPG]

Bought an old Magna 610 18" jigsaw (with the large aluminum "C" arm) some time ago and learned after purchase that I was sold a unit with some missing parts ( lower guide post assembly creating tension on the blade beneath the table). I purchased some spare parts and attempted to install the blade guide assembly , but the fiber rod hits the lower chuck assembly when the jigsaw shaft is rotated.

With the newly purchased blade guide installed, the lower blade chuck assembly always hits the fiber rod in the blade guide since the height of the lower blade chuck cannot be extended with the unit properly affixed to the housing. Also the threads of the blade guide are insufficient,even at that height to secure the blade guide to the jigsaw housing and bearing assembly case.

Has anyone ever seen this before? Is there an adjustment on the jigsaw which decreases the travel action of the lower chuck assembly preventing the assembly from extending to such a height beneath the table and hitting the fiber rod in the jigsaw lower guide post? Or have I purchased a unit which is beyond help? All other parts work fine, but the stability of the jigsaw blade is not the best since the fiber rod in the lower guide post cannot be adjusted without the lower chuck hitting it.

Any thoughts, or assistance with this would be greatly appreciated. Thanks again in advance ---- popjack

A pix would help! It is possible it is not assembled properly.

[SDSSmith]

This may be a dumb question but the lower backup rod holder has an angled hole that should point up (not down) toward the back of the blade. You do have it installed this way don't you? The lower backup also should have a jam nut on it so that you can raise it high enough above the lower chuck and lock it there.

[popjack]

Thanks for your comments. I should have included some pictures (since they are worth a thousand words). I have attached one picture of three showing the lower chuck in its lowest position with the lower guide post and fiber rod installed. The guide post is installed with the rod pointing upwards to the blade.

The second picture shows the lower chuck hitting the guide post on the Magna 610 jigsaw. The lower chuck is not fully extended and will not fully complete its cycle since the drive shaft cannot be turned due to the lower chuck being obstructed by the guide post fiber rod.

the third and last photograph shows the blade inserted into the lower chuck. The fiber rod cannot be properly be positioned to support the blade since it hits the guide post. Note in the photograph, the guide post is raised to its highest position (about two threads into the housing with the nut maintaining tension holding the post to the housing.)

I removed the lower chuck jaw to determine if old blades were hindering the proper mounting of the lower chuck jaw assembly, but is was clean and clear with the jaw assembly securely mounting against the lower chuck shaft.

In speaking with Shopsmith Tech Support, they indicated that perhaps the jigsaw was incorrectly re-assembled or an internal cotter pin may be missing since there are three holes in the lower chuck shaft and a cotter pin in one of the positions which limits the lower chuck shaft travel. The case does not leak and is full of oil so I hate to take it apart if I don't have to if this is not a possiblity in resolving the issue.

I'm fresh out of ideas in limiting the travel of the lower chuck shaft so it does not hit the guide post and fiber rod. In your experiences, is incorrect assembly of the jigsaw gearbox a possibility? What pitfalls could I face or be careful of in dis-assembly or assembly of the unit. I thank you in advance for your comments. ---- popjack

[SDSSmith]

Thanks for your comments. I should have included some pictures (since they are worth a thousand words). I have attached one picture of three showing the lower chuck in its lowest position with the lower guide post and fiber rod installed. The guide post is installed with the rod pointing upwards to the blade.

The second picture shows the lower chuck hitting the guide post on the Magna 610 jigsaw. The lower chuck is not fully extended and will not fully complete its cycle since the drive shaft cannot be turned due to the lower chuck being obstructed by the guide post fiber rod.

the third and last photograph shows the blade inserted into the lower chuck. The fiber rod cannot be properly be positioned to support the blade since it hits the guide post. Note in the photograph, the guide post is raised to its highest position (about two threads into the housing with the nut maintaining tension holding the post to the housing.)

I removed the lower chuck jaw to determine if old blades were hindering the proper mounting of the lower chuck jaw assembly, but is was clean and clear with the jaw assembly securely mounting against the lower chuck shaft.

In speaking with Shopsmith Tech Support, they indicated that perhaps the jigsaw was incorrectly re-assembled or an internal cotter pin may be missing since there are three holes in the lower chuck shaft and a cotter pin in one of the positions which limits the lower chuck shaft travel. The case does not leak and is full of oil so I hate to take it apart if I don't have to if this is not a possiblity in resolving the issue.

I'm fresh out of ideas in limiting the travel of the lower chuck shaft so it does not hit the guide post and fiber rod. In your experiences, is incorrect assembly of the jigsaw gearbox a possibility? What pitfalls could I face or be careful of in dis-assembly or assembly of the unit. I thank you in advance for your comments. ---- popjack

Based on the picture of the chuck at the bottom end of the stroke, it appears as though your chuck is higher than mine. I would guess that either the chuck is not all the way down on the lower shaft or you will be opening the jigsaw up.

The stroke on the jigsaw should be around 7/8", that's fixed. Inside the drive shaft turns a crank that engages a yoke assembly. The yoke assembly converts the circular motion to linear motion. The yoke assembly uses a set screw to position it on the lower shaft. As I recall there is a hole or a dimple for the set screw to engage for proper position. Your jigsaw may have been reassembled with the lower shaft too high in the yoke assembly.

Hope this helps.

[JPG]

Two things:

1) The blade clamping screw in your pix appears to be backwards(the flat end should be against the blade, and the slot should be on the outside[so ya kin adjust it!]).

2) The clamp appears to be high on the shaft. Remove it and observe the location of the holes near the end of the shaft. There should be two that are 90 degrees apart. The set screw must bottom into one of the holes(the clamp may be mounted in two positions 90 degrees apart).

If the shaft has been scored by improper set screw location, file down any high spots before reassembling.

Like Rob said, if this does not get it right, we need to look inside.

BTW, it doesn't leak because it is dry is it???

[popjack]

Ahhh,yes. I changed the orientation of the headless screw in the lower chuck after I took the pictures. It is now corrected. The lower chuck is affixed to the top of the lower chuck shaft. Luckily there were no burrs in the metal and the two parts mated seamlessly. Two holes are at the top of the shaft at a 90 degree offset from each other for mounting the chuck at different positions. Checking this was great advice I never would have contemplated or undertaken.

I removed the metal cover and machine screw beneath it to check the oil level ever since I used the machine. It is full. I believe the previous owner had reworked the 610 (which is why the oil level was full when I recieved the unit) and that is why I beleive there are problems with the installation of the guide post ( which was the missing part when I received the jigsaw). Unfortunately, the unit will be dis-assembled and odds are that the drive shaft may not be properly positioned in the lower chuck shaft. At the lowest point of travel without the lower chuck mounted at the shaft, the top of the lower chuck shaft is about 7/8" above the housing. At its highest point of travel the top of the lower chuck shaft is about 1 13/16" from the top of the housing.

With all the information you have kindly forwarded to me, it's safe to say the unit will have to be dis-assembled and the problem likely lies within the base housing. This is a great forum and with all the advice, I feel more confident in proceeding with the repair. Thanks again. I'll keep you aprised of the outcome. --- popjack

[chipdavis1]

Thanks for this post. I am having the same problem.