Building a hitch on MCI 7

Tenor · May 29, 2009, 07:24:37 PM

I am following Gumpy's hitch that he built for his father in law.
Here is the link:

http://www.busconversions.com/bbs/index.php?topic=8888.0

A difference is that I am using 2x4 box stock for the main crossmember and I have an issue to overcome. The flat plates follow the curve of the body and my 2x4 is straight. I am getting a gap of about 1/4 inch between the plates and the crossmember at the outermost ends. My plates are 3/8 inch, and wouldn't easily bend. I have a notch cut in the bottom of the 2x4 to accept the reciever. I see a few options, and I'd like your opinions.

I could:

1. Use some scrap stock, fill in the gaps and weld up.
2. Cut the 2x4 at an angle where it meets the reciever and make the angle (I'm thinking this might be best)
3. Weld everything square and shim the plates where they meet the outside of the curve in the body. (probably the worst)

Thanks in advance!
Glenn

rdbishop · May 29, 2009, 07:47:19 PM

Glenn,

I have a MC-7with a Reciever I welded a angle iron on each end,drilled 4 holes and mounted it to the frame. On page 2 of all topics,oil leak repair, you can see it in on of the pictures but not real well. If you'd like I'll take some better ones tomorrow. It's not as strong a gumpys, but I'd pull anything with it. Just a nuther idea.

Richard

Tenor · May 29, 2009, 08:06:22 PM

RD,
I don't see the picture and I don't see a link to your photobucket account. Could you help me out? Thanks!

Glenn

rdbishop · May 29, 2009, 09:02:49 PM

Glenn,

Here's a picture.

Tenor · May 30, 2009, 03:56:31 AM

Great photos Richard! I assume you drilled and tapped your frame for the bolts? How much material is in the frame at that section?

Glenn

gumpy · May 30, 2009, 05:51:58 AM

Quote from: Tenor on May 29, 2009, 07:24:37 PM
I am following Gumpy's hitch that he built for his father in law.
Here is the link:

http://www.busconversions.com/bbs/index.php?topic=8888.0

A difference is that I am using 2x4 box stock for the main crossmember and I have an issue to overcome. The flat plates follow the curve of the body and my 2x4 is straight. I am getting a gap of about 1/4 inch between the plates and the crossmember at the outermost ends. My plates are 3/8 inch, and wouldn't easily bend. I have a notch cut in the bottom of the 2x4 to accept the reciever. I see a few options, and I'd like your opinions.

I could:

1. Use some scrap stock, fill in the gaps and weld up.
2. Cut the 2x4 at an angle where it meets the reciever and make the angle (I'm thinking this might be best)
3. Weld everything square and shim the plates where they meet the outside of the curve in the body. (probably the worst)

Thanks in advance!
Glenn

Glenn,
We had the same problem. That's why we cut the main beam at an angle, and inserted the receiver tube. The two sides come in from an angle from the side plates which
are at a slight angle due to the curvature. Look closely at the 4th photo on the old thread. You can see the angle in the support plates below the receiver.

craig

Tenor · May 30, 2009, 06:39:09 AM

I thought so Craig. I'll do the same thing. Just ran out of wire while repairing the corner triangles and it just started raining. I'll get back on it soon. Thanks!

Glenn

rdbishop · May 30, 2009, 07:59:13 AM

Glenn,
Here's some better pics

bobofthenorth · May 30, 2009, 11:00:47 AM

I'm sorry guys but I don't like it. This hitch displays the same fundamental design error that I have seen on too many bus hitches. If I understand the photos correctly the same piece of square tubing (3 x 3 it looks like) is expected to both carry the weight of the towed attachment as well as pull the load. I'm no engineer (no surprises there!) so I can't explain why that is bad in technical terms but the farmer explanation is this: you need something to carry the weight and something to pull the load. What I see in the photos is adequate to carry the weight but there needs to be some forward extension to help pull the load. IMHO.

This is an example of what I am talking about, although its not the best picture. The cross member at the extreme rear which carries the vertical load from the receiver tube is easily visible. If you look closely though you can see that the receiver tube also extends forward to a second crossmember which helps distribute the pulling load. The OP's hitch as built may very well function for a long time and may never give him a problem but doing it right the first time takes very little additional effort.

Tenor · May 31, 2009, 05:54:20 PM

Here is picture of the hitch so far. The flat plates are 3/8, the crossmember is 2x4. I think I will take a page from Richard's and weld angle stock to the crossmember to bolt onto the frame for additional strength. Here is the link to photobucket for more pictures:

http://s613.photobucket.com/albums/tt216/tenor007/
Glenn

bobofthenorth · May 31, 2009, 06:32:16 PM

You've got half a hitch as far as I am concerned. What you have built is adequate to hold the vertical load on the receiver. Figure out some way to attach the other end of the receiver tube further forward on the frame and you will have a complete hitch. IMO.

(on edit)
If you ever plan to do anything more than flat tow a very light towed then you need something heavier for the cross member. That looks like 125 wall tubing - even if it is 188 wall it isn't heavy enough. You are asking that tubing to both carry and pull the load. It can't do it.

Tenor · May 31, 2009, 06:54:06 PM

bob,
The 2x4 is between 3/16 and 1/4 inch, the same as my factory hitch on my truck that carries a 1964 Ford Galaxie on a car hauler. The cross member weighs over 30 lbs. Any heavier and I'd need a trailer to carry my hitch!

Am I missing something?

Glenn

gumpy · May 31, 2009, 07:09:55 PM

Quote from: bobofthenorth on May 31, 2009, 06:32:16 PM
You've got half a hitch as far as I am concerned. What you have built is adequate to hold the vertical load on the receiver. Figure out some way to attach the other end of the receiver tube further forward on the frame and you will have a complete hitch. IMO.

(on edit)
If you ever plan to do anything more than flat tow a very light towed then you need something heavier for the cross member. That looks like 125 wall tubing - even if it is 188 wall it isn't heavy enough. You are asking that tubing to both carry and pull the load. It can't do it.

I disagree. He's got a good start. He needs to grind the top weld and plate across the seam, and then plate across the receiver tube after it's welded in. He's already repaired the triangle frame members. The tube and side plates look fine for towing a toad or small trailer, which is all the bus is really designed to handle. I don't think he's planning on pulling a 15000 lb trailer.

bobofthenorth · May 31, 2009, 07:10:40 PM

You aren't missing anything other than that its a bad design and its not heavy enough. But its your hitch.

gumpy · May 31, 2009, 07:23:28 PM

Quote from: bobofthenorth on May 31, 2009, 07:10:40 PM
You aren't missing anything other than that its a bad design and its not heavy enough. But its your hitch.

The hitch is fine. It's attached with ten 1/2" bolts and welded solid. If his engine cradle is in good condition (and I'm sure he's checked that, considering he's repaired the braces) that hitch will pull any toad 4-down, and will handle a trailer up to about 10000 lbs.