Shopsmith Forums

Probably a simple solution to you ER experts, but I'm flummoxed trying to free up the Upper Chuck on my newly acquired 10ER jig saw. Here's what I've tried thus far:
- Penetrating oil overnight
- Persuasive tapping with wood block & mallet
- Addition of heat to the Spring Cylinder and Upper Guide Bearing

Should I apply more "persuasion"? Worried I'll break something.

Should I take apart the Spring Cylinder via its top nut? Is there a diagram somewhere that explains what's inside and what to look for that's causing the cylinder be frozen up?

For reference, freeing up the Spring Cylinder was no easy feat on this jig saw either. But it finally relented to a combination of the above techniques.

See photo from the original user guide for reference.

Thanks in advance,

David

From your description it appears that the Upper Chuck Assembly is "Stuck" (not moving) in the Spring Cylinder Assembly. I had this problem recently with a later Model A-34 Jig Saw I am restoring. It is my 9th Model A-34 Jig Saw restoration and have had similar a "sticking" problem before. With the assemblies removed from the upper arm of the Jig Saw and upside down I used penetrating oil and it finally broke free. I also used penetrating oil in the screw hole for the Guide Screw. This took some time to happen and several applications, but I was not in a hurry. I am not sure what was keeping the Upper Chuck Assembly from moving inside the Spring Cylinder Assembly, but it moves now. I didn't find any corrosion. Before doing any additional attempts, I would suggest removing all the parts you can from the assemblies. Removing the Leather Pump Seal prior to using penetrating oils can save it from possible damage. After around 70 years the Leather Pump Seals tend to be in questionable shape anyway. Also getting all the parts removed down to and including the spring gets access to both sides of the problem. I still have not gotten the Spring Guide unscrewed and the Spring removed. The Spring Guide is stuck on the threads. Probably more penetrating oil and it is difficult to get it off if it cannot turn freely on the threads. Honestly, I haven't tried that much since the Upper Chuck Assembly was "unstuck" form the Spring Cylinder Assembly.

I would refrain from using "persuasive tapping" or heat to get it free. These Jig Saws have not been made for almost 70 years and replacement parts are hard to find.

Since you are showing a section of page 4 of the early Jig Saw Manual, I hope you have the entire 8 pages available. The back cover, page 8 shows the exploded view of the parts and on page 7 is the parts list. Either the early or late manual will help as the only difference to the Jig Saw from the early version to the later version is the Lower Frame, the Drive Housing Cover and the number of Screws used to hold the drive housing cover on. There was also a change in the Table Insert going from the closed Keyhole to the open Keyhole about the same time.

EDIT: For anyone else reading this and wondering the Lower Frame of the early model does not have any Belt coverage. The later version does.

Russ - grateful for your fast advice and your encouraging words. I'll set aside my "tools of persuasion" for the time being and see about full disassembly and more penetrating oil. I do have the full manual so I'll study the exploded parts diagram on the back closely as I move forward.

Thanks!

David,

I believe patience is the key here. Using a penetrating oil to help free the parts is best. It is likely the dissimilar metals in contact with each other and a lack of oil on the parts from sitting or poor maintenance is causing them to stick. I had mentioned the Leather Pump Seal before and how bad they can get after so long. I have made a replacement out of a piece of leather from an old belt that I shaped over the Spring Guide that the seal sits on. It worked well. You could use rubber "washers" of the correct size or cut to size as an option. After freeing the parts, cleaning them up and before reassembling them do make sure to add a couple drops of oil to the point between the Upper Chuck Assembly where it slides in and out of the Spring Cylinder Assembly to keep them moving freely in the future. A few drops of oil inside the Drive Housing on the moving parts too. A lightweight machine oil like 3 in 1 oil, Zoom Spout Oiler or similar works fine. The same oil to use for the items under TAKING CARE OF YOUR JIG SAW on the top of page 7 in the manual. The Zoom Spout Oiler works well for any hard to reach places.

At the time the Model 10 Shopsmith's and this Jig Saw were made the manufacturers hadn't started recommending using Johnsons Paste Wax as a lubricant and protectant for bare metal parts. Using JPW or similar paste wax has an advantage over oil on parts exposed to saw dust. Saw dust will stick to oil and make a "gummy" mess that has to be cleaned off and redone after about every use. Waxing the outside of the Spring Cylinder Assembly, the Hold Down Support Assembly rod and the openings in the Upper Arm they go into will help keep them moving freely. The PDF below is a supplement to the Model 10E and 10ER Owner's Guides about waxing instead of applying oil to bare metal parts and the same can be applied to the bare metal parts on the Jig Saw.


Even though the oil on the surface will be exposed I still recommend adding a couple drops of oil to the point between the Upper Chuck Assembly where it slides in and out of the Spring Cylinder Assembly to keep it moving freely as opposed to using paste wax there.

Old habits will die hard.

In another thread it was recently revealed that JPW is no longer being manufactured.

Hope TREWAX stays available!

I am not sure if the last poster, olivergray, is talking about the same parts since he refers to a "10ER Spring Cylinder."

The alloy cast upper chuck of the A-34 Jig Saw appears, upon inspection, to be held on to the steel shaft of the Upper Chuck Assembly by a metal pin. I have not tried to separate the upper chuck itself from the steel shaft on any of the 11 Upper Chuck/Spring Cylinder Assemblies I have owned. I haven't needed to do that to get the Upper Chuck Assembly out of the Spring Cylinder Assembly. These alloy cast parts, upper and lower chucks plus others are a bit fragile so care should be taken when working on or around them. The alloy cast end of the Hold Down Support Assembly was fractured on one of my Jig Saws restorations. These parts are not easy to find replacements for so use caution.

In the process of refurbishing a later Model A-34 Jig Saw, I just encountered this issue. The Upper Chuck Assembly was previously stuck inside the Spring Cylinder Assembly, however it is now free to rotate.

Nice.

Hi David, fnf
I suugest applying more penetrating oil to the Upper Chuck.