Register now to get rid of these ads!

Technical Bear Claw Latch and Window Regulators - Install in a 1930 Model A Coupe (a Repost)

Discussion in 'The Hokey Ass Message Board' started by Canuck, Mar 26, 2018.

  1. Canuck
    Joined: Jan 4, 2002
    Posts: 1,058


    Still getting requests on the details of how I did this, especially after Photoshop killed all the oroginal pictures. After noticing a few other postings on installing Bear-claw latches in similar settings where the window channel interfers, I decided to recreate this part of my original build thread.

    Wanted something more secure than the original Ford Model A style latches. Had heard too many stories from friends of doors popping open when going around corners. Also didn’t want to have to slam the doors to close them. A more modern latch mechanism was the answer.

    One of the concerns I had with bear claw mechanisms was the short amount of movement to release the latch. Seemed like it could be dangerous if someone touched the handle when driving. This was taken care of in the build.

    Decided to use a small DUAL arm bear claw mechanism. The dual arms allow a link for the outside door handle and a separate link for the inside handle. A link to the latches that I used, models 9-400-R and 9-400-L, similar to the 9D-400-UR and 9D-400-UL without the dovetail. These units also are FMVSS approved.

    Bought the kit at “Back to the 50s” in Minn. From one of the small vendors. They have two levers, one for interior and one for exterior handles. Made in Canada. Numerous other styles are also available. Also try McMaster-Carr in the US.

    One of the fun things to work around on a Model A is the windows, they go all the way back to the door frame, no room to get linkage around the window easily. The latch mechanism has to be on the inside of the window track and then protrudes about 1/2 inch further into the car than original.

    The door frame was trimmed away and an adapter plate that came with the latches modified and welded on. The modification was just a trimming to angle the top and bottom back to the door frame to cover the previously mentioned ½”. This moved the latch about ¾” into the car.


    The door jamb by the quarter window had the catch removed and a plate welded in where the latch was originally then replaced by a plate with a pin screwed into a captured nut. This plate was trimmed (sharpie marks) to match the profile of the door and an inside lip welded on to mount the wind-lacing too.

    The outside handle is a stock replacement Model A item operating a modified Model A latch with the bolt section removed and the hole filled, but the lock for the driver’s door retained and the stock locking handle on the passenger side . The pivot in the original latch has an arm BRAZED on for the new linkage (cast, so it does't like being welded) and all new springs installed. Worn pivot holes were rebuilt as well. This latch also provides support for the outside handle.

    The inside door release is a NOS 48 Chevy remote, one that matches the splines on the window mechanism that I am using and the actuating rod has plate (white coloured metal by remote) with a slot so the release of the latch occurs near the end of the handle travel.


    If you are doing this be careful that the handle remote will not cause an over-travel on the bear-claw mechanism. Had a similar set up on a 47 Chevy using the original remote and a Mazda latch. Pulled the doors closed using the interior handle and an over-travel of the linkage bent the latch mechanism forcing us to do an NASCAR exit thru the window and a lot of fun trying to get the door open.

    This was rectified with a small stop fashioned out of angle iron bolted to the door at the remotes location to act as a stop.

    A pivot in the door frame below the window track handles the change in motion and gets the linkage down and around the window. Used a bracket rosette welded to the doors frame with a removable pin and a two armed bell crank that was fashioned out of a piece of tubing and some scrap. Bell crank has a pre lubed bronze bushing for easy operation and has a slot in one arm so the release of the latch occurs near the end of the outside handle travel. The slot in the bell crank shows the area where the linkage just slides without moving the arm of the latch.


    Linkage is retained by spring clips on all ends except one with a Heim style
    end at the bellcrank to allow some adjustment. All linkage works under tension to prevent bending. Springs in the original model A latch (rebuilt) and the Chevy remote seem to be adequate. An additional spring may be added between the bell crank and door frame during assembly just to insure operation under all conditions.

    Also check for a posting by “AHotRod” titled "Safety Door Latches in Model A with operating Windows". That was my inspiration for my build with a different approach but similar results.

    Combined with the new rack and pinion style window regulator mechanism that gives a smooth positive action and the awsum hinges from Blue Chip Engineering, now called (“prime is not a crime” on the HAMB) the doors now work better than when they were new. Can’t say too much about the hinges, only difference between their product and the originals is no rust pits, perfect fit.

    A report on this installation after using for 2 years. Worked perfect, smooth and effortless. The only problem was with the Vintique Repro locking handle on the passenger side, The lock mechanism in the handle packed it in after about the second time it was used.

    Window Regulators

    Looking for a cheap reliable window regulator mechanism to replace the worn out and damaged units in my Model A, I came across a 85 Jeep Cherokee that looked like they could be modified easily. The units were removed from the rear doors, as they would get less use than the front doors. If you are going to try this make sure that you get the special nuts and tension washers that hold the lower link to the Jeep windows, you will need them before you are finished.

    The 1985 Jeep Cherokee window regulator. The original regulator laid on the Model A door for comparison

    Since the handle mount was too low to fit the Model A doors, the first step was relocating it up 5 ½” Drill out the four rivets with a 21/64 drill to open up the regulator. This positions the handle within approximately 1 ¾” of the original.

    Next VERY CAREFULLY straightened the track between the two mounting brackets and opened up the loop at the top a little. Do this with the flexible track still in the channel using care not to kink or collapse the track.

    The bottom Window travel stop on the assembly is just a crimped section of the track, Open this up and remove the flexible shaft.

    I my case I wanted to move the handle up 5 “ so I duplicated the original notch in the track 5 “ closer to the top of the loop.

    Then relocated the regulator mechanism over the new notch and welded the rivet holes to join the two halves together. I also put a couple of spots of braze to hold the mechanism from moving on the track. The two original mounting brackets were trimmed and bent closer to the track and the flexible shaft re-installed. Old verses the modified mechanism

    The next step is drilling the door for the two mounting brackets and two holes for the regulator handle mount and one for the handle shaft . In my case I also had to bend a clearance notch for the shaft tube into the door frame. Shim the regulator assembly if required.


    The last step is sourcing a piece of window mounting channel from your scrap pile or friendly local Auto Glass store. Make a bracket to weld to the channel with a hole for the metric bolt that goes into the special nuts on the connecting link. Weld bracket to window mounting channel.

    A couple of pieces of glass setting tape from your Auto Glass store and install the channel on the bottom of your window then bolt it to the connecting link and you are almost done. Replicate the crimped bottom stop in the channel that was opened up in Fig 4, where required by your particular installation.

    For a handle, look for pre 1948 GM handles, they are the same spline size. The shaft of the regulator may require a bit of finessing to fit the pre 48 GM handles. The spline on the shaft is a little longer. A bit of a touch with a grinder should take care of it in a couple of minutes.

    A report on this installation after 2 years on the road, lift mechanism worked smooth and effortless for lowering the window, but required a bit of effort to raise the window. Not excessive enough to be a problem, but more than I anticipated. Otherwise a economical solid install. Also can’t work the window down from outside like you can a original Model A.
    Last edited: Mar 26, 2018
  2. Canuck
    Joined: Jan 4, 2002
    Posts: 1,058


    OK now
    Last edited: Mar 26, 2018
  3. Jalopy Joker
    Joined: Sep 3, 2006
    Posts: 25,485

    Jalopy Joker

  4. Nice job, what you showed is exactly what I tell people about the problem with Model A's - the window channel does not have room to squeeze the latch in between the door edge and the window channel. Bumping it out is a good solution.

    Your bellcrank fix is also a good solution to get the outside handle motion converted to release the latch.

    Another compliment on your adapting of the Jeep window regulator. Old style hot rodding using junkyard parts. That Jeep regulator looks like it could be used for many different hot rod applications. I'll have to keep that in mind for my future projects.
    C Corso and lothiandon1940 like this.

  5. patterg2003
    Joined: Sep 21, 2014
    Posts: 637


    Thank you for taking the time to repost the latches and window actuators with photos. I followed the build thread and enjoyed your ingenuity & creativity. I book marked the page for the window actuator as it saves a lot of headaches to make a good working system. The Nailhead was great install as well. A lot of valued information went into the dark ages with the loss of photobucket. That speaks loudly for everyone to insert the photos direct as you have done so it remains for posterity.
    lothiandon1940 likes this.
  6. fiftyv8
    Joined: Mar 11, 2007
    Posts: 5,132

    from CO & WA

    Great work Canuck, thanks for reposting such valuable information.
    I hope some others will feel the same need to repost pic's in some of their old threads.
  7. belair
    Joined: Jul 10, 2006
    Posts: 8,574


  8. KustomKreeps
    Joined: Jan 7, 2016
    Posts: 325


    tapeing a marker/sharper to the door where the bear claw latch will be then closing the door to mark the pillar can save a heap of time sorting out where to put the stiker.
  9. goldmountain
    Joined: Jun 12, 2016
    Posts: 2,424


    Excellent timing! Having done just about every mistake possible mounting my door glass, you reposted this. Got me some window regulators from my sister's old dead '89 Dodge Colt.
    lothiandon1940 likes this.
  10. Thanks for fixing pic issue.

Share This Page

Register now to get rid of these ads!


Copyright © 1995-2020 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.