Lock N Stitch

[Marc Roberts]

I am thinking about Lock N Stitch as a repair method on a cracked water jacket. This is for a Buick Model 14, not a Model T, so replacement or risking any futher damage in the repair method is not really an option. I am thinking that the planning is every bit as important as the actual drilling and tapping. The latter I am sure I can do. Having no prior experience with such crack repairs, I am trying to decide if I can do this myself. Does anyone who has done this have any thoughts?

[JTT3]

If it was a run of the mill T engine I’d say give it a try. It’s not so I’d leave it to someone with lots of experience. Be prepared for the cost, generally $100 plus an inch.
If you’re going to decide to go the diy route, practice on another block that is not valuable. The kit to do the repair is expensive so it’s going to cost you to practice. There is definitely a learning curve but it does get easier each screw you set.

[Dan McEachern]

The biggest concern when you start to pin a water jacket crack is finding out the metal around the crack is not thick enough to hold the pins. There has to be sufficient thickness for there to be enough threads to keep the pin in place. As far as doing it yourself- no reason not to try. Its tedious work but ..............

[robert daniello]

I highly recommend Frank Casey of Millbury MA. I am fortunate that he is local to me, but he receives broken iron from all across the country. If he can't stitch it, it can't be stitched.

[Dan Hatch]

I do it quite a bit. First thing to do is call them. They are great people to do business with. Tell them what you are working on and they will help you figure if their system is best for the job. You can even send it to them for repair.
Depends on thickness of the cracked area.
Good luck Dan

[BobUkPipedream]

Maybe not best advice here, but I did my repair with stainless threaded rod. I drilled and tapped a hole in the middle of the crack. Then I threaded in the rod and then drilled an over lapping hole and did the same again and so on. I used a welder with stainless 309LSI wire to weld across the ends of the studs, this was not necessary and I should have just used J&B weld on the threads instead. However it sealed up good.

So best thing is just use threaded rod with a bit of loctitie or JB epoxy weld and it will be good. Don’t do the welder as it can crack with cooling and is just not necessary.

https://www.youtube.com/watch?v=95HSHAZGfq0

[Mark Nunn]

Nice video, Bob. I've seen that same method used to repair a crack in a John Deere tractor block. There was a John Deere restorer near my home for years. He used bolts rather than threaded rod but the concept is the same. After smoothing out the repair, he used a heavy-duty twisted-wire grinder wire wheel on the repair surface. That roughened the surface to look like fresh cast iron.

[BRENT in 10-uh-C]

I am thinking about Lock N Stitch as a repair method on a cracked water jacket. This is for a Buick Model 14, not a Model T, so replacement or risking any futher damage in the repair method is not really an option. I am thinking that the planning is every bit as important as the actual drilling and tapping. The latter I am sure I can do. Having no prior experience with such crack repairs, I am trying to decide if I can do this myself. Does anyone who has done this have any thoughts?

As an engine rebuilder who encounters cracks on a frequent basis, I do use a Lock N Stitch method to repair internal areas however if it is an external water jacket area, I generally use a product called Muggy-Weld. Do a Google search and you will find more info on this.

[J and M Machine]

I am thinking about Lock N Stitch as a repair method on a cracked water jacket. This is for a Buick Model 14, not a Model T, so replacement or risking any futher damage in the repair method is not really an option. I am thinking that the planning is every bit as important as the actual drilling and tapping. The latter I am sure I can do. Having no prior experience with such crack repairs, I am trying to decide if I can do this myself. Does anyone who has done this have any thoughts?

Problem is with any crack repair yo need to know how thick metal is as others have mentioned in the comments.

If you saw the video that someone posted ,it's a perfect example of HOW Not to Repair a block. "
These pictures represent a before and after of crack repair. The prior shop used JB weld the repair it ,that's why it's grooved out basically making casting weaker.
After thermally cleaning block all was exposed and we could see what they did wrong.
The parent material to be crack repaired has to be at least 3/16" thick for the pins to secure to.
if that isn't available we would cut the damaged area out and stitch a piece in.

The stitch pins have to intersect with each other so no gap is allowed, then there are locks that go across to keep it secure. As seen in the after picture above.

I would recommend that the block get cleaned and then magnafluxed "Crack checked" to make sure what you're looking at is the only one.

[BobUkPipedream]

Well I did say my way was not the best advice and doing this again, I would just use threaded rod on its own with no groove and no welding. It is not as good as lock n stitch obviously, however if it is the fairly standard ‘no antifreeze cracked water jacket’ issue, then the objective is to just seal the hole. Some people use JB weld and nothing else - I am not saying that is right either.

I guess it comes down to access to money and expertise, both of these seem to be in short supply right now, in fact every time I go to a proper engineering shop they seem to take ages to mess it up and then charge me a ton of cash. Right now I am trying to lap in valves which should be quick but the place that cut the seats must have been doing it as Friday job with a cutter from 1929 that has been used continuously since 1929… I was still fuming about my bent Scat crank as well as the place that quoted $250 to hone the bore and skim the deck and then after doing it demanded $500… maybe I am just cursed…

[BRENT in 10-uh-C]

Well I did say my way was not the best advice and doing this again, I would just use threaded rod on its own with no groove and no welding. It is not as good as lock n stitch obviously, however if it is the fairly standard ‘no antifreeze cracked water jacket’ issue, then the objective is to just seal the hole. Some people use JB weld and nothing else - I am not saying that is right either.

I guess it comes down to access to money and expertise, both of these seem to be in short supply right now, in fact every time I go to a proper engineering shop they seem to take ages to mess it up and then charge me a ton of cash. Right now I am trying to lap in valves which should be quick but the place that cut the seats must have been doing it as Friday job with a cutter from 1929 that has been used continuously since 1929… I was still fuming about my bent Scat crank as well as the place that quoted $250 to hone the bore and skim the deck and then after doing it demanded $500… maybe I am just cursed…

Bob, there is a perceived difference between butchers & restorers, ...and from my professional perspective, sometimes people have a tough time understanding the difference.

Lapping valves should be an easy job providing the seat machining has been done with proper tools, however I am/we are unsure exactly what the circumstances are. Are/were the valve guide bores within tolerance to properly pilot the cutter? Did the shop who did the work have a rigid seat machine?? Did they have a proper-fitting pilot and cutter, (-or a dull Neway-style seat cutter)??? If the answer to any of these question is No, then the issue started when the engine block was left at that shop. All too often, I find hobbyists tend to look for the most frugal financial way yet complain when the results are less than their expectations.

As for the method you described above regarding the crack, I must confess that I cringed when I read that. Even with your disclaimers, IMHO this was not something that should be considered, -especially in a day & time where the correct methods are nearly just as affordable. A cast-iron tapered pin repair, -or the Lock & Stitch method is much superior, and should be the minimum standards by which the repair was made. Imagine a unsuspecting hobbyist obtaining, ...and later sending your repaired block to a professional engine rebuilder only to find that machinist recommending to the hobbyist that another replacement block be found due to the very unstable repair. Then imagine if a 2-cylinder Buick engine block was repaired like your post where a replacement block likely would be non-existent.

The expertise is still out there with "proper engineering shops', so that is NOT where the issue is. Therefore, maybe the lack of 'money' spent by some hobbyists is where the issues lie?? It should be noted that there are some hobbyists that are playing in a hobby they really cannot afford. I have been around this hobby for 60+ years, and it used to be that craftsmanship and common-sense overcame a shortage of money. Unfortunately, it would appear that in today's hobby there are some hobbyists that not only lack the money, -but also lack skill-set and common-sense when it comes to preserving an antique automobile. Yes, I know that sounds brutal, but prove me wrong! It is never wrong to do it the right way!!

[BobUkPipedream]

Okay, I thought I had just logged into the Jaguar E Type forum by mistake…

You must be lucky over there in the USA, because during my years, I have seen a real decline in proper machine shops, parts quality and general ‘professional’ trades. I have literally just walked in the door from pulling the carb off my plane because the official manufacturer (actually in the USA) messed it up either due to float height or putting the wrong jet in it and it also has a leak too. Apparently this is not unknown despite it being fairly important for the task of keeping the engine running and the pilot alive and well. The carb will be taking a trip back to the USA under warranty and with a few choice words from me as I don’t expect this from a $2000 carb for a plane that I fly my son in.

Maybe I am cursed though as my $1600 Scat crank for the T was delivered bent - 4 thou bent. Fortunately my trusty pipe bender worked and I got it back to straight (come to think of it that crank was from the USA too).

I could go with other examples as I have many, from car bits to boat bits to simple things like plasma cutter nozzles. I think much of this was in decline already, but COVID made it worse as people left companies and quality dropped.

As for my butchery, well perhaps I should not have responded as my repair was something that I could do as I have a fair bit of experience with welding, fabrication and it was on a very non structural part of the engine. I must confess I also did not notice the original poster was talking about something other than a T. However putting aside that and just talking about T’s, they are not exactly stressed engines and probably over half of the ones running today are carrying a multitude of faults. They are a cheap vintage car and although Babbitt is not easy or cheap, they are fairly forgiving. If T’s become perceived as an elitist pursuit that needs professional skill and a $50,000 kitty to keep running, then the hobby will die out and they will eventually disappear from the roads. In my small view, we should be encouraging people to join in and try and learn, otherwise what is the point and who will replace all the old guard when they swing the crank handle for the last time?

So my car is now approaching completion with new pistons at 4.5 thou clearance, reground cam, scat crank (now straight), bearings all at 1.5 thou lapped in with timesaver… I have been very fussy at every stage. The only real issues I have had have been with parts manufacturers and engineering shops who have not done the job to the level of quality I expect. For example I needed the block honing again because the first shop I went to ignored my instructions and set piston clearance to 2 thou… luckily I checked because I always check.

Anyway, I have no desire to prove you wrong and will let it rest that I am a butcher without skill or common sense. Fortunately I am a lucky butcher and all the cars, houses, motorcycles, boat and plane that I built over the years have not yet killed me.

[BRENT in 10-uh-C]

Okay, I thought I had just logged into the Jaguar E Type forum by mistake…

You must be lucky over there in the USA, because during my years, I have seen a real decline in proper machine shops, parts quality and general ‘professional’ trades. I have literally just walked in the door from pulling the carb off my plane because the official manufacturer (actually in the USA) messed it up either due to float height or putting the wrong jet in it and it also has a leak too. Apparently this is not unknown despite it being fairly important for the task of keeping the engine running and the pilot alive and well. The carb will be taking a trip back to the USA under warranty and with a few choice words from me as I don’t expect this from a $2000 carb for a plane that I fly my son in.

Maybe I am cursed though as my $1600 Scat crank for the T was delivered bent - 4 thou bent. Fortunately my trusty pipe bender worked and I got it back to straight (come to think of it that crank was from the USA too).



Anyway, I have no desire to prove you wrong and will let it rest that I am a butcher without skill or common sense. Fortunately I am a lucky butcher and all the cars, houses, motorcycles, boat and plane that I built over the years have not yet killed me.

I'll just leave it at this, ...if you used a pipe bender to straighten a new SCAT crank, that was a 'hack'. I straighten many early engine crankshafts (-SCAT included) both before, -and after I grind them by a peening method.

[BobUkPipedream]

Yep, it was a hack fixing an issue with a brand new shaft that I had waited a year for from a major supplier that has a warranty set on date of order not delivery. Now why grind a new shaft when obviously the bend had been induced by over tightening the chucks in the final stages of machining? Another words why grind down a new shaft that just needed a bend taking out? It would have then meant that with a then undersize crank, I would have had to re pour all the Babbitt too, something which is not easy or cheap in the UK.

So decision making is not always straightforward, particularly when you are thousands of miles from suppliers, dealing with parts that are difficult to source and balancing risk.

What matters is the final result and as the second video shows, I got the straightness down to a point where my dial indicator could not even measure any out of true. Despite having 1.5 thou on all the bearings after using timesaver, I could still turn the engine by hand on one of the throws even with pistons, transmission, fourth main and rope seals fitted. So end result is perfect, so call it a hack if you want, but the end result is what counts.

https://www.youtube.com/watch?v=F6DsNxP9hio

https://www.youtube.com/watch?v=TuTGXiy7zkU

[BRENT in 10-uh-C]

Yep, it was a hack fixing an issue with a brand new shaft that I had waited a year for from a major supplier that has a warranty set on date of order not delivery. Now why grind a new shaft when obviously the bend had been induced by over tightening the chucks in the final stages of machining? Another words why grind down a new shaft that just needed a bend taking out? It would have then meant that with a then undersize crank, I would have had to re pour all the Babbitt too, something which is not easy or cheap in the UK.

So decision making is not always straightforward, particularly when you are thousands of miles from suppliers, dealing with parts that are difficult to source and balancing risk.

What matters is the final result and as the second video shows, I got the straightness down to a point where my dial indicator could not even measure any out of true. Despite having 1.5 thou on all the bearings after using timesaver, I could still turn the engine by hand on one of the throws even with pistons, transmission, fourth main and rope seals fitted. So end result is perfect, so call it a hack if you want, but the end result is what counts.

https://www.youtube.com/watch?v=F6DsNxP9hio

https://www.youtube.com/watch?v=TuTGXiy7zkU

Geez Bob, I am not here to debate you in this because it serves no purpose other than to possibly educate others so they do not make the same mistake(s) as you have. With that said, I will address your above post.

It now appears to me that you feel you know procedurally how to properly restore a Model-T engine and its components however please allow me to tell you that you have a strong misunderstanding of various facts.

If I may say this for clarification purposes, you really are/were not purchasing a high-end race crankshaft when you purchase the T4000 crank. You basically are/were purchasing a crankshaft that can be used 'as-is' out of the box, -or as most quality engine rebuilders do (-when they blueprint an engine), they first check & straighten it to their standards, re-polish it to their RA preferences, and then balance it to their preferred weight. I am grateful that Tom even took on the project of manufacturing an affordable aftermarket crankshaft for a Model-T. If you have ever had a custom-made crankshaft for a vintage engine, you will know that the prices for those are generally 2X, to as much as 4X what you paid for your T crankshaft. In the past, there have been other aftermarket T crankshafts manufactured however they have either been prone to failures, -or the costs to manufacture them exceeded a ROI for the manufacturer. My point is SCAT is not getting rich at the present price point with these, -and again, I am extremely thankful we have as good of quality as we have at an affordable price point.

Next, as for your other statement about overtightening chucks, et/al, it has become apparent to me that you are not an experienced crankshaft grinder. First, my crankshaft grinder does not even use chucks, ...and a large percentage of crankshaft grinding machines also do not use chucks. Instead, my machine uses centers to fixture the crankshaft. For the record, grinders with chucks have no reason to "over tightening the chucks in the final stages of machining" as that is not what introduces bending. That generally only happens when centers are used, ...but even then, we use a steadyrest to eliminate this from happening. Because crankshaft grinding is done by plunge cutting, this allows us to grind one side of the journal pin and then move to the opposite side. The logistics of changing tension in the later stages of machining would create a tapered or egg-shaped journal. You made no mention of that any pins were out of specifications. Therefore you are in error about your theories posted above.

Also while we are speaking about errors, just know that if you straightened your crankshaft in a press, you are going to find that the crankshaft will be bent by the same amount after a few run cycles. Do the research on peening to straighten vs. just cold bending in a press. Yes, a welded crankshaft is often placed in a press to place the pin under compression however it is peened while under that compression where there will be no springback when the pressure has been released. Therefore your videos might be entertaining for someone who is uneducated to watch, however they are very misleading on facts. As I stated above, you are welcome to post as many rebutals as you like however I am finished debating you, and/or your craftsmanship, and this needs to be my last comments with regard to your topic(s). Might I suggest instead of posting a rebuttal of my information, you first fact-check everything I have written and verify what I have stated is indeed correct. Thanks

[BobUkPipedream]

There is no doubt you have a huge amount of knowledge and yes chucks, centres etc. I do not use the correct language. I have not ground a crankshaft, I am not an engine builder. I do not purport to be either. I am just an enthusiast seeking to build a fun car at the weekends in my garage. Anyway, perhaps you could use your knowledge to tell me why my crank was bent out of the very well supported and undamaged box? However if those were you last comments, then at least I get the last word, which given your comments about me so far, does seem fair.

The thing I hate about forums is that rather than just finding or giving advice, people have to get mean and personal. It is why I rarely comment and instead just search the posts for answers. NOTE: that I have not been rude to you, I have not commented on your skills or made assertions about your wealth, intelligence or craftsmanship. This whole exchange reminds of some the threads on the forum from the mid 2010s and the vast flurry of insults exchanged between frustrated old men. Mildly entertaining at times, yet also completely at odds with what a forum or community should be.

Finally, I do wish to make it clear that I am appreciative of Scat making cranks. However Scat charge $1700 for a crank and by the time I get it, it is about $2300. I am happy they do produce the cranks, but as they charge $3-400 for other cranks, I think it is safe to say that they may not make much on the Model A / T crank production runs, but I don’t think they do it as a favour either. Now when the Chinese start grinding those cranks as well as forging them so as to undercut Scat, Scat will have to rely on quality and patriotism to keep them in business. Speaking as someone whose country used to produce something like 70% of the global motorbike market and then lost it all in the matter of a decade or so to the Japanese; I think it pays to not become complacent with quality, particularly when facing a growing China. Scat is not a charity and neither are we. The best thing for Scat’s continued success and both model T’s long term supply of cranks and Scat’s future is to keep quality up. I will also add that they should also answer emails - after my polite email stating the problem with the crank, they answered one to say they would get back to me the following week, then nothing, nada, zilch. Even Langs could not get an answer. Fortunately for me, Langs were exceptionally helpful and made me a lifelong fan of their business.

Now I must get back to butchering my T, l may be a shady tree type for guy who has not had his torque wrench calibrated and I may have static balanced the transmission like some kind of Neanderthal, but at least I enjoy tinkering with my T.

[AndyClary]

To the original poster. Lock N Stitch will make an excellent repair if, as previously mentioned, your block has sufficient integrity to take it. Expensive but like you said there aren’t near as many Buick blocks laying around.

To the well meaning. Most of us at some time or another have made a sketchy repair. The fact that we might have gotten away with it doesn’t mean we should recommend it to others. I include myself on that list.


Andy

[BobUkPipedream]

Fair point Andy, however much of the forum and indeed T folklore and aftermarket accessories are in the sketchy box. Come to think of it the T is in the sketchy box and even was in 1926 or so thanks to the braking system. When I hit issues and ask a question, I value all responses from the gold plated right down to the grab a file, hammer and duct tape. I have no wish to belittle or insult anyone. I then choose the advice I heed depending on my budget, particular issue and risk appetite. It would be a shame if the forum became restricted in its responses as it would soon become restricted in its membership and indeed its relevance to the T enthusiast.