Morso UP-m

[guzzijim]

Thanks to Roboframer for giving me the link to the Morso UP-M Manual, I've now topped up the oil now.

I've always had problems with the Morso underpinner when using Minerva type mouldings, wood mouldings are no problem.

Since I've now a printed manual to hand I thought I would investigate my problem further.

The first thing I found was the Left and Right Hand Table Plates (00512 & 00510) were not flat, when I placed a steel straight edge across them, the were higher at the extremities ie. forming a slight Vee.

Anyone that uses Cyanoacrylate glue will know it's strong but brittle, so not having a flat and true table causes problems, the previously glued mitre is put under tension and sometimes cracks.

I've solved this problem by machining the Base Frame (014499) so that the Table Plates are now true.

Another annoying thing is the face where the vee nails come out of is slightly lower than the table plates, another possibility for stressing the joint, but there is nothing I can do to remedy this.

This otherwise well engineered bit of kit has been let down by two basic faults (in my humble opinion)

[Not your average framer]

Finding things like this on secondhand equipment does not mean that it left the factory like this.

Components may become distorted, or worn with time, wear and usage. Also the surface where the wedges appear from may well have a means of adjusting it's height and may have settled over time into an out of alignment position. Over the years any glue build up on the surface has probably been removed by scrapping, which may not have helped the problem either.

I bought most of my equipment as secondhand and my experience is that such problems are not particularly uncommon. Being an ex-engineer these things don't bother me very much, as I can usually identify and fix most problems. Your existing corrective actions would suggest to me that you will probably have the ability to find a way of correcting this last problem as well. I hope that you will succeed in getting this machine up to the standard that you are hoping for.

[prospero]

That's a perfect demo for not gluing joints - letting them set up and then underpinning. I know a lot of folks do this. The glue is always the strength of the joint. The wedges act as internal clamps to hold the faces tight while the glue sets and thereafter to protect the integrity of the joint and hold things in place in case of catastrophic failure. Insertion of wedges is quite a violent procedure, so doing it into a joint where the glue has set has always seemed a bit counter-intuitive to me.

[guzzijim]

That's a perfect demo for not gluing joints - letting them set up and then underpinning. I know a lot of folks do this. The glue is always the strength of the joint. The wedges act as internal clamps to hold the faces tight while the glue sets and thereafter to protect the integrity of the joint and hold things in place in case of catastrophic failure. Insertion of wedges is quite a violent procedure, so doing it into a joint where the glue has set has always seemed a bit counter-intuitive to me.

Ok, so what glue would you use ? obviously Cyanoacrylate type glues would not be suitable as they bond very quickly.


I've just seen this on Lion, it says it takes 3-6 days to set, I guess that's not a problem if the joint is held tight by the vee nails. http://www.lionpic.co.uk/product/Lion-P ... 924,0.aspx

Anyone else using this method with Plastibond or other polymer glue ??

[prospero]

I don't use poly moulding very much. When I have used it I've used PVA as per usual. I did try a home-made concoction using expanded polystyrene bits (from packing) dissolved in acetone. Amazing just how much goes in a jam-jar. That literally welds the joint together. It's a bit messy though and you have to be careful not to get it on the face of the moulding. Didn't matter in my case as I was respraying the frame.

[guzzijim]

Finding things like this on secondhand equipment does not mean that it left the factory like this.

Components may become distorted, or worn with time, wear and usage. Also the surface where the wedges appear from may well have a means of adjusting it's height and may have settled over time into an out of alignment position.

.

These things are built like Tanks. The working surface is made of 1/4" steel plate, the rim of the support box is 3/8" x 1 1/2" doubt you could distort it if you ran a bus over it. There is absolutely no means of adjusting the height of where the vee nails come out of, I may well try and make a shim to go on top. I was interested in what prospero said in a later post about not using instant set glue, will play later!!!!

[guzzijim]

Prospero, I've just made a test polymer frame using PVA adhesive, I stacked 3 vee nails in each corner, absolutely no problems.

Now is the PVA good enough for Polymer or should I use Pastibond ? will leave frame for 24 hours and do a destructive test.

Moulding used http://www.lionpic.co.uk/product/19mm-M ... 919,0.aspx

[Not your average framer]

Please correct me if I an wrong, but I don't think that Plastibond still available. It is still in the index at the back of the Lion catalogue, however when you turn to the page number, which is the page for framing adhesives Plastibond is no longer there. I don't think that this product has been available from Lion for some time.

Some of the specialist PVA type adhesives available for the construction industry claim to be formulated for sticking plastic items such as lightweight plastic cladding, so it may be worth investigating some of these adhesives further.

[guzzijim]

Please correct me if I am wrong, but I don't think that Plastibond still available. It is still in the index at the back of the Lion catalogue,
Some of the specialist PVA type adhesives available for the construction industry claim to be formulated for sticking plastic items such as lightweight plastic cladding, so it may be worth investigating some of these adhesives further.

You're right PLASTIBOND longer available, tried normal PVA yesterday absolutely useless,I am in the process of doing another test piece (un-pinned) this time leaving to cook above the central heating boiler, but I expect the same result.

So I'm looking for for a non-instant bond glue that does REALLY glue Polymer! I found the link below and and want to know if anybody uses one of these products, perhaps I overlooked a product ?

https://www.youtube.com/watch?v=VrHue6QrnAk

[guzzijim]

[quote=,I am in the process of doing another test piece (un-pinned) this time leaving to cook above the central heating boiler, but I expect the same result.

k

Anybody that thinks normal PVA will have any glueing effect on Polymer frames is kidding themselves, wallpaper paste would do a better job.

I am now awaiting PU glue to arrive, the local store sells large bottles, it has a habit of going of in the bottle, inverting the bottle helps I'm lead to understand.(I intend buying small bottles)

PU has foams / expands x4 as it sets, only a tiny amount strategically placed is required, however it does mean I can glue and v-nail at the same time.

The foaming /expansion process is worrying but so was applying the right amount of superglue gel, so I guess I'll get used to it, hopefully.

[prospero]

Hmmmm.... I wouldn't use PU glue. It's just too tricky to control. Poly mouldings vary just like wood. Some will have a more open structure inside - more cavities in other words. PVA glue will seep into the holes and form a bridge even if it doesn't chemically bond to the plastic. It all depends on how strong you want the joint to be. On a small frame PVA is quite sufficient. If you want strength use polystyrene cement which will weld the faces. Keeping it well away from the finish. It's messy stuff, but will work better than PU as it doesn't expand.

[guzzijim]

More Bedtime reading. !!!!!!!!




http://www.militarymodelling.com/news/a ... ives/10590

[MITREMAN]

Try Humbro prosision glue, great for polymer moulding , get it from you local model shop, give you a little to work with to

[guzzijim]

Try Humbro prosision glue, great for polymer moulding , get it from you local model shop, give you a little to work with to

Thanks will try that after I've tried this (waiting on postman). http://www.shop4glue.com/flexy-cyano-20 ... e-86-p.asp

Incidentally I've further modified my Morso UP-M, the head from where the v-nails are ejected is now absolutely level with table, what a job every thing that I need to machine was face-hardened.

[Kevlar]

Hi Guzzijim, I use evostick impact adhesive for polymer mouldings and have to date not experienced any problems with it. I did try a few different glues to start with, including two part glues (what a pain in the proverbial that was!! ) There is a slight difference in that I add only a small amount of glue onto 4 moulding faces of the eight, then bring together and underpin straight away. I dont wait for the glue reach its maximum strength the following day. I figure that (and its has never let me down yet,) the impact adhesive gets a good hold pretty quickly and then is forced together more so with the underpinning. Its not expensive glue either, might be worth a try.

[guzzijim]

My cyanoacrylate adhesives arrived from http://www.Shop4Glue.com this morning, I immediately did a sheer test with their Clear'ntuff (ca014) Rubber Roughened Cyanoacrylate, I underpinned within 2minutes, I stacked wedges till they were just starting to distort mouldings surface and the mitre didn’t open ! I later forced the L test piece open and found the glue was obviously stronger than the polymer moulding!
The disadvantage is it very thin and runny, but the dispenser allows (if trimmed correctly) you to deposit 5 very small blobs (as on a domino) away from the face edges.
I always work on silicon release paper when assembling; this allows the pieces to be slid into place without resistance and also stops excess glue fixing your frame to the work bench or whatever you’re working on.
Early days I know, but with the underpinner mods. and now an adhesive which works I’m feeling confident.
I found http://www.Shop4Glue.com recommended on a previous FF posting, there the guy recommended Instatite Medium which I have also bought but not tried, it looks of similar viscosity as my Clear'ntuff so I would buy either thick or gel next time.!