Too tight Top Mount

[Shane Betts]

Just unpacking our Red (YAY!) and assembling and I've hit a little hitch.

We've only got one top mount (will order another this week) and this one just doesn't sit down far enough to thread both bolts. Sending it back to the factory isn't high on my agenda as we're in Australia so my option seems a slight mod. I don't want to ream the holes as there is little enough meat there now, so I plan to file the one or two millimetres I need off the mount where it grounds on the camera body.

Question I have is, does anyone from Red know exactly where that point is? It seems to be the point at the end of the arc, just below the bolt holes. I'd like to take off as little as possible to make this work.

[ericyoung]

Hi Bettsy

Had the same issue - it's probably less than a millimetre. See my post here:

http://reduser.net/forum/showthread.php?t=22672

Brent & I had a little private email exchange, but I managed to get the front top mount to fit on the body. I did have to use a bit more force than I liked to do so, and I had to start with the top mount held away from the body a little to allow some play at the end of the bolts to start seating perpendicularly into the body holes before tightening them to pull the top mount gently into place. This removed some of the anodising and scraped some fine metal swarf out of the bottom of the mounting holes on the top mount, so tolerances were on the edge here. I think that the tolerance that was off here was the front plate being very slightly above the rest of the body. Unfortunately, the same procedure is necessary if you remove and then remount the top mount, but mine are going to live on the camera, so not too much of a problem.

This procedure was not necessary on the rear of the body, where the holes on the mount and the body lined up almost exactly, so I was able to use just fingers to put the bolts in without any danger of the bolts going in at angle with a risk of crossthreading. Ie NO force or fiddling about was necessary.

I sent Brent some photos of the problem and he was looking into the issue, but hasn't come back to me yet

[Shane Betts]

Thanks Eric, I did see your post. Glad to know it's not just me.

Seems to me the Top Mount is at fault here. On our Red the mount won't bolt at all on the front and only the right side screws in on the rear. I'm not prepared to risk the threads on the body for the sake of a little filing on a US$250 casting and that way, even if I have to mod every Top Mount that comes into the building, it'll take me twenty minutes all up and everything will fit hunky dory.

The Top Mount to me seems a little confused as to what it's mating surface actually is. Certainly the radius of that arc is not the same as that of the top of the camera.

All that said, I'm extremely impressed with the build quality of the gear. Very excited and can't wait to get the thing on a tripod and shoot some stuff. Now, if only we had some CF cards:sarcasm:

[Shane Betts]

http://www.reduser.net/forum/uploaded/2655_1229389794.jpg

Woops! I've just voided the warranty on my Top Mount:)

Just a mill or two needed with a draw file on the arc (both sides, although more on one). The area circled need the most work but very little more than a coat of paint in places and it all fits like a dream and the bolts thread cleanly with no pressure on the body helicoils.

It's a very minor thing but could I perhaps suggest the castings be modified by 1mm at those points? This wouldn't affect the strength of the mount at all and would avoid situations like this in those very rare (two so far) occasions where the tolerances are a bit tight.

[Jarred Land]

http://www.reduser.net/forum/uploaded/2655_1229389794.jpg

Woops! I've just voided the warranty on my Top Mount:)

If your Top Mount was Janky out of the box... don't worry we will replace it, even though you took the hacksaw to it :)

[Shane Betts]

Hey Jarred. See, that's why I love you guys! Try to get that kind of response from the Big Guys.

If it's all the same with you I'd be happy to just cruise on as we are thank you. It fits now without stress on the body and we don't have to bother with sending things back and forth across the pond. I'll emery it back to a smooth finish, give it a coat of automotive paint and nobody will be any the wiser (I've been doing this kind of stuff since I was a kid).

When the other one arrives (which will be soon after we actually order it), nobody will be able to tell them apart. And by the way, it was a jeweler's draw file:-)