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I had absolutely no success retrieving the nut I dropped into the transmission, so in desperation I decided I would pull the whole engine and turn the thing upside down. When I got the apron off from under the radiator, I discovered the front cross member of the frame is broken in two.
I don't see them listed for sale by the venders. Can this be welded?
I wouldn't trust a weld without some sort of reinforcing plate on the inside. To install a plate on the inside, the break would have to be away from the spring area. The more I think about it, the more I believe you should remove the broken cross member and install another. There's a piece in Tinkerin Tips on making a backing plate for the hard to reach rivets. I have seen some which were bolted instead of riveted.
Though you won't find it in a catalogue, you can probably find a replacement. Try Lang's (978) 297-1919, Model T Haven (620) 365-6709, or Neunhoffers' (830) 257-8168. There are others, but I'd start with those. The rivets are a catalogue item.
By the way, I don't remember this being a difficult job, but it's good to have a helper to hold something heavy behind the rivets when you mash them.
The break is right in the middle where the spring mounts. Looks like there isn't much room inside for a reinforcing plate, so I will start looking for a replacement. If I were going to pound aluminum rivets, I would use an air hammer. Will that work to mash these rivets?
Oh, by the way, the engine is out, the nut is out of the transmission. Should be easier to install the bands and put the hogshead back on outside the car. While it's out I will pull the pan and inspect everything. Sure hope this doesn't turn into a major overhaul that keeps me out of the tours this summer.
Randall, that crossmember can be welded very easily. Find a good welding shop, they can fix you up. It ain't rocket science. Dave
As crappy as it is to drop a washer in the transmission, It really is lucky you did, and can fix your frame properly!!!!
Don't use aluminum rivets,they are not as strong as steel rivets. A air hammer may or may not work as they are different from air rivet guns. A 3x rivet gun would work fine and heating the rivet cherry red and driving (or bucking) while red hot makes the job easier. Some air hammers just don't have the power. Like trying to drive a railroad spike with a small ball peen hammer.
Agree, use steel rivets and heat them cherry first, then have a helper. One to operate the air rivet gun, one to be the buck holder. On the front crossmember there are places you can wedge the buck to back the rivet when setting.


This frame had a replacement cross member that was bolted with course thrd. cheap fasteners. So a rivet kit from Big Flats Rivet Co was used to do it right.
If you choose to use bolts, then use high quality Grade 8, lock washers, and Locktite on the threads too. Ream the holes to make those bolt shanks fit real tight.
The rivet guns are all over eBay very reasonably priced. Here is an example:
http://cgi.ebay.com/Jiffy-APT-3X-300-AVC-12-Rivet-Gun-Aircraft-Tools-/2004645925 41?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item2eac9eee9d
If you live near a major airport the local pawn shops often have them for very low prices.
Good comes out of bad it always seems. Aren't you glad you dropped that nut in there?
The rivet gun on Ebay is an air chisel with no rivet heads. Don't know if it will if it will drive rivets.
If you are going to buy a "Air Hammer", buy a "3X Rivet Gun" and a air regulator to attach to the grip. Then you can always adjust the pressure down to do light work.
Just weld it...either in the car or removed and replaced. It will be just as good as any replacement cross member you will find. The riveting exercise should be a pain, particularly if the frame is still attached to the car. Bucking and heading will be torture. If you must rivet, then clean the areas and provide a good fit and braze them in place.
Randal:
I replaced a broken cross member and did it by myself, I orderd the rivets from Big Flats,along with several bucking bars for the different size rivets then I made sure the holes were good and installed two or three at a time and heated them to cherry red and bucked them tight. Went to the next bunch and backed them with a block and bucked them and primed and painted and ala no one will ever know it was changed. I hope I gave a good description of the way I did it. Any Randal good luck take your time and do a good job, don't rush, as haste makes waste and you want it right and depenable. Lastly make sure you dont get a warp inthe frame as you install the rivets. Keep everything level. Now I will hope this post the way it should.!
I actually have a rivet gun, bought it to work on aircraft sheet metal (1946 Aeronca Champ), I mis-spoke when I said air hammer. I've got a friend who welds and has a 26 roadster, so I think I'll go that way. I took the pan off to see if there was anything else in there, and everything good and clean. Now to get pan gaskets and start re-assembly. At least it will be easy to get the band installed and the hogs head back on.
putting bands in a T with the pan AND hogshead off is sorta like changing a fan belt with the fan off.
Don't forget to put them on and tie the ends before you put the pan on.
There is very little load on the front cross member.
The weight of the front end of the engine sits on the spring.
The frame rails carry the weight of the radiator and a portion of the rest of the car.
I'd get a used cross member and bolt it in with threaded rivets. Restoration Supplies in Escondido has 5/16" threaded rivets.
Or just use bolts.
I see no reason why you couldn't just weld the frame. If you get a good weld, the other metal on the cross member would break before the weld.
I agree with Ned wholeheartedly. Dave
Post a picture of the damage.
I have repaired 2 crossmembers and replaced 2 over the years.
Either job has it's plus's and minus's as far as time and such.Rerivoting a replacement would be the ultimate way to fix it.But welding is a close second.
Here is photos of 1 repair I made on the chassis that is now under my pickup project,trouble free for a couple or 3 years now.
This was before the spring bolt hole was redone.
This is the worst of the 2 I repaired.I tacked in it place like you see in the first picture.I then ground out the hole so I could make a patch peice to fit.Welded it in,welded the vertical cracks,and then plated underneath.I used clamps,tie down straps and such to get everything back in place before welding.
make sure to get a proper measurement on the raditor mounting hole specs before welding anything to make sure you wont have trouble later.
The other chassis was just a weld up where it had been cut out from around a tree.I put a 1/8th plate under the crossmember,where the spring pad goes.I cant help but feel like it cant hurt.
Model T frames are designed to twist and in practice they do twist a lot.
That's why they are riveded and should only be repaired by riveting or bolting.
A break as in the pictures that Mack posted should hold up a long time in todays driving and road conditions though.
I would not want my frames welded in the corners though.
Aaron, definately not! You are correct, they need to be able to twist. Dave
Allthough I aint able to test my theory,I think the early spring holder that uses 2 clamps,is more apt to cause a break that 1 that uses only 1 clamp.It looks to me that the 2 clamps pull down on each side of the spring center,keeping the crossmember in a bind.
I took the day off and spent it with the family today instead of the T. My break is in the same place as the top picture Mack posted. No cracks near the ends, so a weld repair will probably work for me. The reinforcing plate idea looks like a good one too. I'm beginning to think the easiest thing will be to remove the piece, weld it, and bolt it back in with grade 8 bolts. It won't show because of the apron in front of it.
Aaron, you're right about putting bands on. I was thinking about replacing the pan then putting bands on, but while looking at the totally exposed drums, it seemed obvious to put them on first. I think I'll try tying things up with dental floss before installing the pan, then put hogshead on and install pedals, etc. You can bet I am going to take a bit more care with the adjusting nuts this time.
Dont remove to weld it,weld it in the car.Use jacks,strapes and such to keep it alligned.In retrospect,I would use a peice of flat iron with holes drilled in it the exact width the radiotor mounted holes should be and bolt it tight on the frame.That way the radiator will drop back on.
The plate i installed was a 1/8th thick piece of flat iron inside the crossmemeber.I used a thin piece of rubber for the spring pad so it would not make a change in how high the chassis was from ground level but think it was not nessasary.just use the standard pad.
Grade 8 bolts will break before stretching or flexing much,unlike a grade 5 automotive bolt.
I wouldnt do that.
Just me,your mileage may vary.
A real airplane guy like you, Randall, would never use grade 8 bolts in a critical application like that. Don't they have AN/MS bolts in free stock at your shop? If not, there's www.AircraftSpruce.com .
Which vibrates more, Randall, your Model T, or your daily driver helicopter? Both machines try to shake themselves apart, huh?
"If something isn't broken on your Model T or helicopter, it's about to break."
rdr
Slightly off topic,from what I understand a aircraft bolt is a grade 8 that has been xrayed for defects?
Aircraft bolts are commonly 160 KSI, the threads are rolled as opposed to cut. Common aircraft bolts are not x-rayed. A specialized bolt such as a trunnion pin or such may be if the manufacture specified it on the part print. This might be where a manufacture started with a standard aircraft bolt and modified it. At that point they become responsible for its servicability as it no longer meets the spec called out for the unmoddified bolt and then they may opt for inspection.
I would not opt for the added strength or expense of aircraft hardware when it comes to a model T. A grade 5 bolt is probably stronger than anything Henry used (certainly stronger than the soft rivets he used). Just my opinion.
Mack mentioned a spring pad. Did you car have on between the springs and the crossmember? It's a necessity.
Aircraft bolts can be many different things. There are aluminum aircraft bolts, for example, that are far weaker than hardware Grade 8. There are AN series aircraft bolts that are also far weaker than Grade 8.
Other aircraft bolts are far stronger than Grade 8. In any case, there are zero aircraft bolts that started life as Grade 8 bolts, X-rayed or otherwise.
A good replacement for a steel rivet would be an NAS 1200 series bolt. There are also 6200 series, which are unnecessarily strong in shear strength, but if you find them on a scrap table why not?
In my business a lot of aircraft hardware gets thrown away in between jobs, just because it is surplus to the job. This is true of the entire industry, so a lot of good bolts end up available cheap from surplus dealers.
Here's one authority, "The Pocket Ref" by TJ Glover:

A buddy came over today to return some borrowed tools and help with transmission band re-assembly. Everything went together well (no parts dropped into the transmission), so he said "Let's look at the frame. Looks like welding it in place will be easy." A few strategically placed clamps, some aligning, and we welded it back together. We added a reinforcing plate and painted, and we're back in business. And I didn't have to remove and replace rivets! As soon as some more parts come in, we'll re-assemble the bendix, add intake and exhaust manifold, and see how much fun it is to put the engine back in.
Way to go Randall. Sometimes the simple fixes are the best. Dave
Randall,
Do you have any pictures of your repair? It would be interesting to see how it went.
Joe
I welded mine too Randall. Was about as bad as Mack's picture. Just cut it into a rectangle and fashioned a piece if 1/4" to fit. Have a friend with a pneumatic machine called a 'Ironworker' that can punch square holes. I measured meticulously before making the spring bolt hole then welded the rectangle onto the crossmember. Works great but, like Warren said, "be sure you use a (rubber - or leather) spring pad when installing the front spring
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