Rolll bar adjustments

[rponfick]

I have a MK5 with only driver roll bar. The rear brace shaft does not line up with the socket in the hoop portion. How do you bend the rear bar to get it to fit? I have wacked it a few times with a rubber hammer, but it doesn't seem to move any. Does shorten the down bar help any?
Thanks, Ralph

[Jeff Kleiner]

Found 2 areas of chassis to roll bar conflict on my Mk5 Beta car that were causing issues---check to see if the hoop is contacting the horizontal square tube across the back of the cockpit (this is the tube that runs side to side several inches above the trunk floor) and also see if the rear down tube is coming into contact with the square tube that runs side to side across the trunk opening (the one that the hinges mount to). I solved both by administering some generous whacks with a big dead blow hammer and afterwards the bars slipped together easily. Erik found similar with his Beta car. We reported it but I don't know if they made any jig adjustments to compensate.

Jeff

[Tango]

Perfect timing on this post as I just discovered this same issue this past weekend. I was just discussing / brainstorming with another MK5 builder who is in the same boat. I also noticed one spot where the rear bar does not go all the way down because of some weld splatter. Thanks for the post!

[Jeff Kleiner]

Perfect timing on this post as I just discovered this same issue this past weekend. I was just discussing / brainstorming with another MK5 builder who is in the same boat. I also noticed one spot where the rear bar does not go all the way down because of some weld splatter. Thanks for the post!

Actual splatter is one thing but that that weld at the bottom of the chassis stub is there on purpose as a stop to prevent it from going all the way down.

Jeff

[rponfick]

Well, I tried rubber hammer, pry bar, filing edges off of rear mounting tube, and nothing is moving.
I am getting a little frustrated.
Will try working on something else as a distraction. Maybe with time it will correct itself.
Ralph

[edwardb]

I assume you're talking about the hoop that has to line up with the two stubs on the chassis? It needs to line up so that it slips on and off without a big effort. As the build progresses (body on/off, final assembly, etc.) you don't want to have to deal with forcing it on and off all the time. I'm assuming the inside the roll bar legs are clean with no burrs or whatever. Some with the frame stubs. Not particularly unusual for the hoop to be the exact width and not line up exactly. It takes some pretty serious force to move it just a little. Hammering on it probably won't do it. Here's what I've done successfully: If it's too wide, large straps that can exert a lot of force can squeeze it together enough to make a difference. I've used the 2-inch tie down straps from my car trailer. If it's too narrow and needs to be opened up, I've used a floor jack to spread. Sounds crazy, and you need to block it so it's held in place and not damaged. But it's worked for me. In either case, you have to go past the amount needed because it will spring back. But be gentle and take several tries so you're not having to both squeeze and expand. Good luck.

BTW, my Mk5 is about 1/16" inch off. I'll be doing the floor jack thing probably later today.

[rponfick]

edwardb, strange as it may be, it is the rear down leg. The hoop fits fairly well. The down leg is inward about 1/4" and it is stout.
Still cogitating.
Ralph

[Jeff Kleiner]

Ralph,
You haven't clarified whether the roll bar hoop or rear leg are contacting either of the chassis members I mentioned in post #2.

Jeff

[rich grsc]

edwardb, strange as it may be, it is the rear down leg. The hoop fits fairly well. The down leg is inward about 1/4" and it is stout.
Still cogitating.
Ralph
Then bend it out a 1/4" and be done with it. You're building a car, NOT a lego, make it work. :rolleyes:

[rponfick]

Ralph,
You haven't clarified whether the roll bar hoop or rear leg are contacting either of the chassis members I mentioned in post #2.

Jeff
Jeff, don't think they are contacting the chassis members. The hoop seems to have two weld spots lumps about 1/2" up from the frame member. It looks like they were put there as stops for the hoop.
The rear leg bottoms on the weld seam, not all the way down the chassis member.
Not sure if this helps.
Thanks, Ralph

[rponfick]

Then bend it out a 1/4" and be done with it. You're building a car, NOT a lego, make it work. :rolleyes:

That is what I have been trying to do. Any suggestions? I bent a 5 foot 3/4' galvanized pipe on it today

[edwardb]

edwardb, strange as it may be, it is the rear down leg. The hoop fits fairly well. The down leg is inward about 1/4" and it is stout.
Still cogitating.
Ralph

Responding to this and the other follow-up comments. I did work on fitting my Mk5 roll bar tonight. My hoop was a little narrow and opened it up with a floor jack. It's still a little tight to get on but not terrible. As for the down leg, it appears they ground out one end some to help assembly because it's a somewhat loose fit on the chassis stub, e,g, can more the angle some. The other end fits perfectly on the roll bar. So check that. The challenge here, as I saw it, was a bit of geometry. Because of the angle of the hoop and down tube, when you're starting to put them together, they don't match up because of the angles. At first glance miss by 1/8-3/16" or maybe a little more. But if you can get the down tube started into the roll bar by pulling on each, you can tap the hoop down into place with a dead blow hammer (don't go crazy) and when everything drops into place, at least for mine lined up exactly. The downtube even could be turned with a little effort. I ground a little bit of a chamfer on the inside of the hoop end of the down tube to help it get started. Also make sure all the tubes and chassis stub ends are clean with no burrs or whatever. Don't know if that helps, but I'm happy with how mine fit.

[danmas]

Ralph,

I’m back in town next week and happy to come give you a hand if you like. I’m not the brightest bulb in the socket but I’m big and reasonably strong. I can come help and bring some jacks and big a$$ hammers.

Dan

[rponfick]

Responding to this and the other follow-up comments. I did work on fitting my Mk5 roll bar tonight. My hoop was a little narrow and opened it up with a floor jack. It's still a little tight to get on but not terrible. As for the down leg, it appears they ground out one end some to help assembly because it's a somewhat loose fit on the chassis stub, e,g, can more the angle some. The other end fits perfectly on the roll bar. So check that. The challenge here, as I saw it, was a bit of geometry. Because of the angle of the hoop and down tube, when you're starting to put them together, they don't match up because of the angles. At first glance miss by 1/8-3/16" or maybe a little more. But if you can get the down tube started into the roll bar by pulling on each, you can tap the hoop down into place with a dead blow hammer (don't go crazy) and when everything drops into place, at least for mine lined up exactly. The downtube even could be turned with a little effort. I ground a little bit of a chamfer on the inside of the hoop end of the down tube to help it get started. Also make sure all the tubes and chassis stub ends are clean with no burrs or whatever. Don't know if that helps, but I'm happy with how mine fit.

You are correct that I can just get the downleg started in the hoop and then pound it down with a rubber hammer, but I have not forced it all the way down out of fear of not being able to remove it. The thing I was concerned about was subsequent install and removal might be an issue with body installed and possible damage.
Thanks, will keep working on it.

[rponfick]

Ralph,

I’m back in town next week and happy to come give you a hand if you like. I’m not the brightest bulb in the socket but I’m big and reasonably strong. I can come help and bring some jacks and big a$$ hammers.

Dan

Thanks, you are an officer and a gentleman.

[Rian_Colorado]

I'm around next week too Ralph. I just bought portable hydraulic ram for something I was working it - maybe we can use it in an attempt to keep Dan from injuring another shoulder!! lol

Here's a link to the tool I bought so you get an idea....

https://www.amazon.com/dp/B0D24YKXT9?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1
BTW, it helped a lot making my footbox wider on the Mk4!

Rian

[rich grsc]

So, has the installation changed? On the older models you installed the down leg first, pushing it all the way down, then the hoop, again pushing it all the way down. After that it was just a matter of pulling the down leg up on the hoop stub.

[rponfick]

I'm around next week too Ralph. I just bought portable hydraulic ram for something I was working it - maybe we can use it in an attempt to keep Dan from injuring another shoulder!! lol

Here's a link to the tool I bought so you get an idea....

https://www.amazon.com/dp/B0D24YKXT9?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1
BTW, it helped a lot making my footbox wider on the Mk4!

Rian
Thanks for the offer. I will take a look at the frame and see if there is a place we can force from. I would hate to fix one problem and then have my frame bent somewhere else.
Dan is a little fragile.
Thanks, Ralph

[danmas]

Dan is a little fragile.
Thanks, Ralph


Just my ego….

[Jeff Kleiner]

So, has the installation changed? On the older models you installed the down leg first, pushing it all the way down, then the hoop, again pushing it all the way down. After that it was just a matter of pulling the down leg up on the hoop stub.

Mk5 goes together the same.

Jeff